WO2006070445A1 - Light source - Google Patents

Light source Download PDF

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Publication number
WO2006070445A1
WO2006070445A1 PCT/JP2004/019587 JP2004019587W WO2006070445A1 WO 2006070445 A1 WO2006070445 A1 WO 2006070445A1 JP 2004019587 W JP2004019587 W JP 2004019587W WO 2006070445 A1 WO2006070445 A1 WO 2006070445A1
Authority
WO
WIPO (PCT)
Prior art keywords
electron
light source
emitter
electrode
voltage
Prior art date
Application number
PCT/JP2004/019587
Other languages
French (fr)
Japanese (ja)
Inventor
Yukihisa Takeuchi
Tsutomu Nanataki
Iwao Ohwada
Takayoshi Akao
Original Assignee
Ngk Insulators, Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ngk Insulators, Ltd. filed Critical Ngk Insulators, Ltd.
Priority to PCT/JP2004/019587 priority Critical patent/WO2006070445A1/en
Priority to CNA2004800234687A priority patent/CN1856857A/en
Publication of WO2006070445A1 publication Critical patent/WO2006070445A1/en

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Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02—Main electrodes
    • H01J1/30—Cold cathodes, e.g. field-emissive cathode
    • H01J1/312—Cold cathodes, e.g. field-emissive cathode having an electric field perpendicular to the surface, e.g. tunnel-effect cathodes of metal-insulator-metal [MIM] type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J63/00—Cathode-ray or electron-stream lamps
    • H01J63/02—Details, e.g. electrode, gas filling, shape of vessel

Definitions

  • the present invention relates to a light source (including a surface light source) using an electron-emitting device having an upper electrode and a lower electrode formed in an emitter section.
  • an electron-emitting device has a drive electrode and a common electrode, and is applied to various applications such as field emission display (FED) and backlight.
  • FED field emission display
  • a plurality of electron-emitting devices are two-dimensionally arranged, and a plurality of phosphors corresponding to these electron-emitting devices are respectively arranged with a predetermined interval.
  • any force having Patent Documents 1 to 15 uses a dielectric for the emitter part. This requires a high voltage for electron emission, and the panel manufacturing process is complicated and the manufacturing cost is high.
  • Non-Patent Documents 1 and 2 below regarding electron emission from a ferrodielectric which is considered to be composed of a dielectric.
  • Patent Document 1 JP-A-1-311533
  • Patent Document 2 JP-A-7-147131
  • Patent Document 3 Japanese Patent Laid-Open No. 2000-285801
  • Patent Document 4 Japanese Patent Publication No. 46-20944
  • Patent Document 5 Japanese Patent Publication No. 44-26125
  • Non-Patent Document 1 Yasuoka, Ishii “Pulse Electron Source Using a Ferroelectric Cathode” Applied Physics No. 68 ⁇ No. 5, p546-550 (1999)
  • Non-Patent Literature 2 V.F.Puchkarev, G.A.Mesyats, On the mechanism of emission from theferroelectric ceramic cathode, J.Appl.Phys., Vol. 78, No. 9, 1 November, 1995, p. 5633-5637
  • the electron emission is not stable and the number of electron emission is up to about several tens of thousands of times. For example, there is a problem that the practicality when used as a light source is poor.
  • the present invention has been made in consideration of such problems, and in an electron-emitting device having an emitter portion made of a dielectric material, excessive emission of electrons is suppressed, and electron emission is suppressed.
  • An object of the present invention is to provide a light source capable of preventing damage and the like in the accompanying electrodes and the like and capable of extending the life and improving the reliability.
  • Another object of the present invention is to easily generate a high electric field concentration, to increase the number of electron emission locations, and to achieve high output and high efficiency for electron emission. Another object is to provide a light source that can be driven at a low voltage.
  • a light source is a light source that generates light when electrons collide with a substance.
  • the electron generation source is an electron-emitting device, and the electron-emitting device is a dielectric.
  • a drive voltage is applied between the first electrode and the second electrode, and the first electrode and the second electrode formed in the emitter portion.
  • the emitter section can be composed of a piezoelectric material, an antiferroelectric material, or an electrostrictive material.
  • the operation of the electron-emitting device according to the first invention will be described.
  • a driving voltage is applied between the first electrode and the second electrode, at least a part of the emitter section undergoes polarization inversion or polarization change, and the potential is lower than that of the second electrode. Electrons are emitted from the vicinity of the electrode. That is, due to this polarization reversal or polarization change, a local concentrated electric field is generated between the first electrode and the positive pole side of the nearby dipole, so that primary electrons are extracted from the first electrode. Pulled out of the first electrode Primary electrons collide with the emitter and secondary electrons are emitted from the emitter.
  • the first electrode, the emitter portion, and the vacuum atmosphere have a triple point
  • primary electrons are extracted from a portion of the first electrode in the vicinity of the triple point, and the extracted 1 Secondary electrons collide with the emitter and secondary electrons are emitted from the emitter.
  • the secondary electrons described here obtain energy from the Coulomb collision of the primary electrons, and electrons inside the solid and auger electrons that have jumped out of the emitter, and primary electrons scattered near the surface of the emitter ( All of the reflected electrons).
  • the thickness of the first electrode is extremely thin (one lOnm)
  • electrons are also emitted by the interface force between the first electrode and the emitter portion.
  • the light source according to the present invention can stably emit electrons, and can achieve more than 2 billion times of electron emission, making it practical as a light source. Rich. However, the amount of emitted electrons increases almost in proportion to the level of the drive voltage applied between the first electrode and the second electrode, so that the amount of emitted electrons can be easily controlled. is there.
  • the electrons drawn to the second electrode ionize mainly the gas existing in the vicinity of the second electrode or the atoms constituting the second electrode into positive ions and electrons.
  • the atoms constituting the second electrode existing in the vicinity of the second electrode are atoms generated as a result of evaporation of a part of the second electrode, and the atoms are in the vicinity of the second electrode. It is floating. Then, the electrons generated by the ionization further ionize the gas, the atoms, etc., so that the number of electrons increases exponentially, and when this proceeds and the electrons and positive ions are neutral, a local plasma is formed.
  • the positive electrode force generated by the ionization for example, the first electrode is damaged by colliding with the first electrode.
  • the first electrode covers emits light. Electron force is attracted by the + pole of the dipole of the emitter that exists as a local anode, and charging to the negative polarity proceeds on the first surface of the emitter in the vicinity of the first electrode. As a result, the electron acceleration factor (local potential difference) is relaxed, the potential leading to secondary electron emission does not exist, and the first surface of the emitter portion is charged negatively. [0016] Therefore, the positive polarity of the local anode in the dipole is weakened, the strength of the electric field between the local anode and the local force sword is reduced, and electron emission is stopped.
  • a light source is a light source that generates light by collision of electrons, wherein the electron generation source is an electron-emitting device, and the electron-emitting device is a dielectric material.
  • the second electrode is formed on a second surface of the emitter portion, and at least the first electrode has a plurality of through portions from which the emitter portion is exposed.
  • the surface of the peripheral portion of the penetrating portion that faces the emitter portion is separated from the force of the emitter portion (second invention).
  • the electron-emitting device emits electrons toward the first electrode force toward the emitter section, the emitter section is charged, and the emitter section force in the second stage. Electron emission may be performed.
  • a driving voltage is applied between the first electrode and the second electrode.
  • This drive voltage is, for example, a pulse voltage or an AC voltage, which is higher or lower than a reference voltage (e.g. OV) over time from a voltage level that is lower or higher than the reference voltage.
  • a reference voltage e.g. OV
  • a triple junction is formed at a contact point between the first surface of the emitter section, the first electrode, and a medium (for example, vacuum) around the electron-emitting device.
  • the triple junction is defined as the electric field concentration portion formed by the contact between the first electrode, the emitter portion, and the vacuum.
  • the triple junction includes a triple point where the first electrode, the emitter part, and the vacuum exist as one point.
  • the triple junction is formed in the peripheral portion of the plurality of through portions and the peripheral portion of the first electrode. Therefore, when the drive voltage as described above is applied between the first electrode and the second electrode, electric field concentration occurs in the triple junction described above.
  • the voltage is higher or lower than the reference voltage, and a voltage is applied between the first electrode and the second electrode, and in the triple junction described above, for example, in one direction.
  • the electric field concentration occurs, and electrons are emitted toward the first electrode force emitter part.
  • the emitter part the part corresponding to the penetrating part of the first electrode or the vicinity of the peripheral part of the first electrode Electrons are accumulated in the part. That is, the emitter portion is charged. At this time, the first electrode functions as an electron supply source.
  • a gap is formed between the surface of the first electrode facing the emitter portion in the peripheral portion of the through portion and the emitter portion. Therefore, when the driving voltage is applied, tl, electric field concentration is likely to occur in the gap portion. This leads to a high efficiency of electron emission and can realize a low driving voltage (electron emission at a low voltage level).
  • a gap is formed between the surface of the first electrode facing the emitter portion in the periphery of the penetrating portion and the emitter portion. Since the peripheral portion of the penetrating portion in the first electrode has a hook shape (flange shape), the electric field concentration in the gap portion is increased, and thus the hook-shaped portion (the peripheral portion of the penetrating portion is ) From electron Is easily released. This leads to a high output and high efficiency of electron emission, and a low drive voltage can be realized. In addition, since the peripheral portion of the penetrating portion in the first electrode functions as a gate electrode (control electrode, focus electron lens, etc.), the straightness of the emitted electrons can be improved. This is advantageous in reducing crosstalk, for example, when a large number of electron-emitting devices are arranged to constitute, for example, a display electron source.
  • the light source according to the first and second inventions includes an AC pulse for reversing or changing polarization of at least a part of the emitter section between the first electrode and the second electrode.
  • the light source according to the first and second inventions includes a third electrode disposed above the emitter section at a position facing the first electrode, and the phosphor is disposed on the third electrode. You may make it comprise and apply
  • the light source according to the first and second inventions is configured by arranging a phosphor around the electron-emitting device and enclosing, for example, mercury particles in an atmosphere between the electron-emitting device and the phosphor. You may do it. In this case, some of the emitted electrons collide with the mercury particles, and the mercury particles are excited to emit ultraviolet rays. When this ultraviolet ray hits the surrounding phosphor, the phosphor is excited and embodied as phosphor emission to the outside.
  • a plurality of electron-emitting devices may be arranged two-dimensionally.
  • a surface light source using an electron-emitting device and capable of extending the life and improving the reliability is realized.
  • the advantages of the surface light source will be explained by the difference from the display.
  • the surface light source may always emit the entire surface, so that it is not necessary to perform complicated driving such as row scanning, for example. Static drive is sufficient.
  • control of the emission spot diameter by electron emission is inadequate. Therefore, it is not necessary to install, for example, a control electrode that functions as a focus lens between the electron-emitting device and the phosphor. This leads to simplification of the mechanical configuration as well as the circuit configuration.
  • the display needs to handle a data signal that changes at high speed according to an image signal.
  • the drive voltage has a complex waveform modulated according to the gradation.
  • a surface light source does not need to handle a data signal that changes at a high speed in accordance with an image signal, so a simple waveform (a waveform with a constant pulse period and pulse width) can be used as a drive voltage. .
  • a power recovery circuit is connected to the surface light source, it is possible to recover almost 100% of the drive voltage as long as the circuit constant and circuit switching timing of the power recovery circuit can be set with high accuracy. It becomes.
  • the plurality of electron-emitting devices are divided into two groups, and when the electron-emitting devices included in one group emit light, the electron-emitting devices included in the other group are included in the one group.
  • the electron emission element included in the other group collects the power of the electron emission element included in the other group when the electron emission element included in the other group emits light. You may do it.
  • the electron-emitting device 1S included in a group other than the group performing the light-emitting operation 1S Mounting area that does not require a separate buffer capacitor because it also serves as a so-called buffer capacitor for power recovery It is possible to effectively reduce the power consumption and power consumption.
  • the drive voltage is modulated based on a control signal, and the light emission is controlled by controlling the electron emission amount of the electron-emitting device. Also good.
  • the light source according to the first and second inventions may include two or more surface light source units.
  • each surface light source unit may include a plurality of the electron-emitting devices, and the plurality of electron-emitting devices may be two-dimensionally arranged.
  • stepwise light control digital light control
  • the driving voltage applied to each electron emission element is modulated based on the corresponding control signal, and the amount of electron emission of the electron emission element is controlled to control each surface light source unit.
  • the dimming the light emission distribution of each surface light source unit can be controlled. In other words, in addition to digital dimming, analog dimming can be realized, and fine dimming can be performed.
  • the plurality of electron-emitting devices included in each surface light source unit are divided into two groups, respectively, and are included in the other group when the electron-emitting devices included in one group emit light. Electron-emitting device force The power of the electron-emitting devices included in the one group is recovered, and when the electron-emitting devices included in the other group emit light, the electron-emitting devices included in one group But let's collect the power of the electron-emitting devices contained in the.
  • the two or more surface light source sections are divided into two groups, and when the electron-emitting devices included in one group emit light, the electron-emitting devices included in the other group are included in the one group. The power of the electron-emitting devices is recovered, and when the light-emitting devices included in the other group emit light, the electron-emitting devices included in one group recover the power of the electron-emitting devices included in the other group.
  • the light source of the present invention in an electron-emitting device having an emitter portion made of a dielectric material, an excessive emission of electrons is suppressed, and an electrode associated with electron emission or the like. Damage, etc. can be prevented, and the service life can be extended and the reliability can be improved.
  • FIG. 1 is a block diagram showing a light source according to a first embodiment.
  • FIG. 2A is a plan view showing an electrode portion of an electron-emitting device
  • FIG. 2B is a plan view showing an electrode portion in a first modification.
  • FIG. 3 is a plan view showing an electrode portion in a second modification.
  • FIG. 4 is a waveform diagram showing a drive voltage output from the drive circuit.
  • FIG. 5 is an explanatory diagram showing an action when a voltage Val is applied between the upper electrode and the lower electrode in the first embodiment.
  • Fig. 6 is an explanatory view showing an electron emission action when a voltage Va2 is applied between the upper electrode and the lower electrode.
  • FIG. 7 is an explanatory view showing the self-stopping action of electron emission accompanying negative charge on the surface of the emitter section.
  • FIG. 8 is a characteristic diagram showing the relationship between the energy of emitted secondary electrons and the amount of secondary electrons emitted.
  • FIG. 9A is a waveform diagram showing an example of a drive voltage
  • FIG. 9B is a waveform diagram showing a change in voltage between the lower electrode and the upper electrode in the electron-emitting device according to the first embodiment. is there.
  • FIG. 10 is a block diagram showing a first modification of the light source according to the first embodiment.
  • FIG. 11 is a configuration diagram showing a second modification of the light source according to the first embodiment.
  • FIG. 12 is a circuit diagram showing a drive circuit.
  • FIG. 13A is a waveform diagram showing a control signal indicating ON / OFF
  • FIG. 13B is a waveform diagram showing a clock
  • FIG. 13C is a waveform diagram showing a timing pulse
  • FIG. 13D is a drive voltage generator. It is a wave form diagram which shows the drive voltage produced
  • FIG. 14 is a circuit diagram conceptually showing a preferred embodiment of the drive circuit.
  • FIG. 15 is a waveform diagram showing the operation of the drive circuit.
  • FIG. 16 is a configuration diagram showing a third modification of the light source according to the first embodiment.
  • FIG. 17 is a waveform diagram showing the operation of the drive circuit corresponding to the light source according to the third modification.
  • FIG. 18 is a circuit diagram showing a drive circuit according to a modification.
  • FIG. 19A is a waveform diagram showing a dimming signal
  • FIG. 19B is an explanatory diagram showing a method of modulating the period T2 in accordance with the voltage level of the dimming signal
  • FIG. 19C is a voltage diagram of the dimming signal.
  • FIG. 6 is an explanatory diagram showing a method of modulating the application period (pulse width) of voltage Va2 according to the level.
  • FIG. 20 is a characteristic diagram showing the relationship between the pulse width of voltage Va2 and luminance.
  • FIG. 21 is a characteristic diagram showing a relationship between collector voltage and luminance.
  • FIG. 22 is a characteristic diagram showing the relationship between the voltage Va2 (voltage level) applied between the upper electrode and the lower electrode and the luminance.
  • FIG. 23 is a characteristic diagram showing the relationship between the voltage Val applied between the upper electrode and the lower electrode and the luminance.
  • FIG. 24 is a configuration diagram showing a fourth modification of the light source according to the first embodiment.
  • FIG. 25 is a configuration diagram showing one electron-emitting device of a light source according to a fourth modification.
  • FIG. 26 is a diagram showing an equivalent circuit mainly composed of a current flowing between the upper electrode and the collector electrode in the electron-emitting device shown in FIG.
  • FIG. 27 is a diagram showing output characteristics (Vkc-Ike characteristics) of the electron-emitting device shown in FIG.
  • FIG. 28 is a diagram showing an equivalent circuit mainly composed of a collector current flowing through the collector electrode and a control current flowing through the control electrode when a control electrode is installed between the upper electrode and the collector electrode.
  • FIG. 29 is a configuration diagram showing a fifth modification of the light source according to the first embodiment.
  • FIG. 30 is a configuration diagram showing a sixth modification of the light source according to the first embodiment.
  • FIG. 31 is a configuration diagram showing a seventh modification of the light source according to the first embodiment.
  • FIG. 32 is a configuration diagram showing an eighth modification of the light source according to the first embodiment.
  • FIG. 33 is a configuration diagram showing a ninth modification of the light source according to the first embodiment.
  • FIG. 34 is a block diagram showing a tenth modification of the light source according to the first embodiment.
  • FIG. 35 shows an eleventh modification of the light source according to the first embodiment.
  • FIG. 36 is a block diagram showing a twelfth modification of the light source according to the first embodiment. 1 37]
  • FIG. 37 shows a light source according to the first embodiment. It is a block diagram which shows the 13th modification of
  • FIG. 38 is a cross-sectional view showing a part of the electron-emitting device used in the light source according to the second embodiment.
  • FIG. 39 is an enlarged cross-sectional view showing the main part of the electron-emitting device.
  • FIG. 40 is a plan view showing an example of the shape of the through-hole formed in the upper electrode.
  • FIG. 41A is a cross-sectional view showing another example of the upper electrode
  • FIG. 41B is a cross-sectional view showing an enlarged main part.
  • FIG. 42A is a cross-sectional view showing still another example of the upper electrode
  • FIG. 42B is a cross-sectional view showing an enlarged main part.
  • FIG. 43 is a diagram showing a voltage waveform of the drive voltage in the first electron emission method.
  • FIG. 44 is an explanatory view showing the state of electron emission in the second output period of the first electron emission method.
  • FIG. 45 is a diagram showing a voltage waveform of a drive voltage in the second electron emission method.
  • FIG. 46 is an explanatory diagram showing a state of electron emission in the second output period of the second electron emission method.
  • FIG. 47 is a diagram showing an example of a cross-sectional shape of a collar portion of the upper electrode.
  • FIG. 48 is a diagram showing another example of the cross-sectional shape of the collar portion of the upper electrode.
  • FIG. 49 is a diagram showing still another example of the cross-sectional shape of the collar portion of the upper electrode.
  • FIG. 50 is an equivalent circuit diagram showing a connection state of various capacitors connected between the upper electrode and the lower electrode.
  • FIG. 51 is a diagram for explaining capacitance calculation of various capacitors connected between an upper electrode and a lower electrode.
  • FIG. 52 is a plan view showing a part of the first modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 53 is a plan view showing a part of the second modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 54 is a cross-sectional view showing a part of the third modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 55 is a diagram showing a voltage-charge amount characteristic (voltage-polarization amount characteristic) of an electron-emitting device used in the light source according to the second embodiment.
  • FIG. 56A is an explanatory diagram showing a state at point pi in FIG. 55
  • FIG. 56B is an explanatory diagram showing a state at point p2 in FIG. 55
  • FIG. 56C is a point from point p2 in FIG. p3 It is explanatory drawing which shows the state until it reaches.
  • FIG. 57A is an explanatory view showing a state from point p3 to point p4 in FIG. 55
  • FIG. 57B is an explanatory view showing a state immediately before reaching point p4 in FIG. 55
  • FIG. FIG. 56 is an explanatory diagram showing a state from point p4 to point p6 in FIG. 55.
  • FIG. 58 is a block diagram showing a light emitting unit and a drive circuit used in the light source according to the second embodiment.
  • FIG. 59A to FIG. 59C are waveform diagrams showing amplitude modulation of a pulse signal by the amplitude modulation circuit.
  • FIG. 60 is a block diagram showing a signal supply circuit according to a modification.
  • FIG. 61A to FIG. 61C are waveform diagrams showing pulse width modulation of a pulse signal by a pulse width modulation circuit.
  • FIG. 62A is a diagram showing a hysteresis curve when the voltage Vsl in FIG. 59A or 61A is applied
  • FIG. 62B is a hysteresis curve when the voltage Vsm in FIG. 59B or 61B is applied
  • 62C is a diagram showing a hysteresis curve when the voltage Vsh in FIG. 59C or FIG. 61C is applied.
  • FIG. 63 is a configuration diagram showing one arrangement example of the collector electrode, the phosphor, and the transparent plate on the upper electrode.
  • FIG. 64 is a configuration diagram showing another arrangement example of the collector electrode, the phosphor, and the transparent plate on the upper electrode.
  • Fig. 65A is a diagram showing the waveforms of the write pulse and the lighting pulse used in the first experimental example (experiment of the electron emission state of the electron-emitting device), and Fig. 65B shows the waveform in the first experimental example.
  • FIG. 6 is a diagram showing a state of electron emission from the electron-emitting device with a detection voltage waveform of the light-receiving device.
  • FIG. 66 is a diagram showing waveforms of an address pulse and a lighting pulse used in the second to fourth experimental examples.
  • FIG. 67 is a characteristic diagram showing the results of a second experimental example (an experiment that shows how the amount of electrons emitted from the electron-emitting device varies depending on the amplitude of the write pulse).
  • FIG. 68 shows a third experimental example (in which the amount of electrons emitted from the electron-emitting device is the amplitude of the lighting pulse) It is a characteristic view which shows the result of the experiment) which looked at how it changes with.
  • FIG. 69 is a characteristic diagram showing the results of a fourth experimental example (an experiment in which the amount of electrons emitted from the electron-emitting device varies depending on the collector voltage level).
  • FIG. 70 is a timing chart showing an example of a light source driving method.
  • FIG. 71 is a table showing a relationship between applied voltages in the driving method shown in FIG. 70.
  • FIG. 70 is a table showing a relationship between applied voltages in the driving method shown in FIG. 70.
  • FIG. 72 is a cross-sectional view showing a part of the first modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 73 is a cross-sectional view showing a second modified example of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 74 is a cross-sectional view showing a third variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 75 is a cross-sectional view showing a fourth variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • FIG. 76 is a cross-sectional view showing a partially modified fifth example of the electron-emitting device used in the light source according to the second embodiment.
  • FIG. 77 is a cross-sectional view showing a sixth variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
  • Timing generator 46 ⁇ -Drive voltage generator
  • the light source 10A includes a light emitting unit 14A in which a plurality of electron emitting elements 12A are two-dimensionally arranged, and each electron emission of the light emitting unit 14A. And a drive circuit 16A for applying a drive voltage Va to the element 12A.
  • the drive circuit 16A includes a first electrode (for example, an upper electrode) 18 and a second electrode of each electron-emitting device 12A based on a control signal Sc indicating lighting Z extinction from the outside (lighting Z extinction switch or the like).
  • a drive voltage Va is applied to the electrode (lower electrode) 20 to control the drive of each electron-emitting device 12A.
  • An example of the driving circuit 16A will be described later.
  • each electron-emitting device 12A is formed on a plate-like emitter portion 22, the upper electrode 18 formed on the surface of the emitter portion 22, and the back surface of the emitter portion 22. And the lower electrode 20.
  • the electron emitter 12A since the electron emitter 12A has a structure in which the emitter 22 is sandwiched between the upper electrode 18 and the lower electrode 20, it becomes a capacitive load. Therefore, the electron-emitting device 12A can be viewed as a kind of capacitor C (see FIG. 12).
  • a drive voltage Va from the drive circuit 16A is applied between the upper electrode 18 and the lower electrode 20.
  • a force is shown when the potential of the lower electrode 20 is made zero by connecting the lower electrode 20 to the GND (ground) via the resistor R1. It doesn't matter.
  • the application of the driving voltage Va between the upper electrode 18 and the lower electrode 20 is performed through a lead electrode 24 extending to the upper electrode 18 and a lead electrode 26 extending to the lower electrode 20 as shown in FIGS. 2A and 2B, for example. .
  • a transparent plate 30 made of, for example, glass or acrylic is disposed above the upper electrode 18, and the transparent plate 3
  • a collector electrode 32 made of, for example, a transparent electrode is disposed on the back surface of 0 (the surface facing the upper electrode 18), and a phosphor 34 is applied to the collector electrode 32.
  • a bias power source 36 bias voltage Vc is connected to the collector electrode 32 via a resistor R2.
  • the electron-emitting device 12A is, of course, arranged in the vacuum space. As shown in FIG. 1, the electron emission element 12A has a force point A where the electric field concentration point A exists as a point including a triple point where the upper electrode 18 / emitter 22 / vacuum exists at one point. Can also be defined.
  • the vacuum level in the atmosphere, 10 2 - 10 6, more preferably Pa is preferred instrument 10 3 - 10 5 P a.
  • the reason for selecting such a range is that, in a low vacuum, (1) because there are many gas molecules in the space, if too much plasma that easily generates plasma is generated too much, a large amount of positive ions There is a risk of colliding with the upper electrode 18 to promote damage, or (2) fluorescence emitted by electrons sufficiently accelerated by the collector potential (Vc) when colliding with gas molecules before the emitted electrons reach the collector electrode 32. This is because the body 34 may not be sufficiently excited.
  • the emitter 22 is made of a dielectric.
  • a dielectric having a relatively high relative dielectric constant for example, 1000 or more can be used.
  • barium titanate such dielectrics include lead zirconate, lead magnesium niobate, -keckle niobate bell, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, nickel tantalum.
  • Lanthanum, calcium, strontium, molybdenum, tungsten, norium, niobium, zinc, nickel, manganese, etc., or any combination of these, or other compounds are appropriately applied to the above-mentioned ceramics. The added one can be mentioned.
  • PMN lead magnesium niobate
  • PT lead titanate
  • a composition in the vicinity of a morphotropic phase boundary (MPB) between tetragonal and rhombohedral is preferable for increasing the relative dielectric constant.
  • PMN: PT: PZ 0.3 75: 0. 375: 0.25
  • PMN: PT: PZ 0.5: 0. 375: 0.125
  • the rate is 4500, which is particularly preferable.
  • it is preferable to improve the dielectric constant by mixing a metal such as platinum into these dielectrics within a range that can ensure insulation. In this case, for example, 20% by weight of platinum may be mixed in the dielectric.
  • a piezoelectric Z electrostrictive layer, an antiferroelectric layer, or the like can be used for the emitter section 22.
  • the piezoelectric Z Examples of electrostrictive layers include lead zirconate, lead magnesium niobate, lead nickel niobate, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, lead nickel tantalate, antimony stannate, titanium Ceramics containing an acid bell, barium titanate, magnesium tungstic acid bell, cobalt niobate bell or the like, or any combination thereof.
  • the compound may contain 50% by weight or more of these compounds.
  • a ceramic containing lead zirconate is most frequently used as a constituent material of the piezoelectric Z electrostrictive layer constituting the emitter section 22.
  • the ceramics may further include oxides such as lanthanum, calcium, strontium, molybdenum, tungsten, norium, niobium, zinc, nickel, manganese, Alternatively, a ceramic obtained by appropriately adding any combination of these or other compounds may be used.
  • ceramics with Si O, CeO, Pb Ge O or any combination thereof added to the ceramics. May be used. Specifically, 0.2 wt% of SiO is added to PT-PZ-PMN piezoelectric material.
  • a material containing 0.1 wt% CeO or 1 to 2 wt% Pb Ge 2 O is preferred.
  • a ceramic containing lead magnesium niobate, lead zirconate and lead titanate as main components and further containing lanthanum or strontium.
  • the piezoelectric Z electrostrictive layer is dense or porous, its porosity is preferably 40% or less.
  • the antiferroelectric layer is mainly composed of lead zirconate as a main component, or a component composed of lead zirconate and lead stannate.
  • lead zirconate As a main component, or a component composed of lead zirconate and lead stannate.
  • the porosity is preferably 30% or less.
  • strontium bismutanoate tantalate (SrBiTaO) was used for the emitter section 22.
  • Such a material with low polarization reversal fatigue is a layered ferroelectric compound and is represented by the general formula (BiO 2 ) 2 + (ABO 2 ) 2 . Where gold
  • the ions of genus A are Ca 2+ , Sr 2+ , Ba Pb 2+ , Bi 3+ , La 3+ etc.
  • the ions of metal B are Ti 4+ , Ta 5+ , Nb 5+ etc.
  • semiconductors can be added to semiconductors by adding additives to barium titanate, lead zirconate, and PZT piezoelectric ceramics.
  • the electric field concentration can be performed in the vicinity of the interface with the upper electrode 18 that contributes to electron emission by providing a non-uniform electric field distribution in the emitter section 22.
  • a piezoelectric Z electrostrictive Z antiferroelectric ceramic with a glass component such as lead borosilicate glass and other low melting point compounds (for example, bismuth oxide), the firing temperature is reduced. Can be lowered.
  • a glass component such as lead borosilicate glass and other low melting point compounds (for example, bismuth oxide).
  • the shape thereof is a sheet-like molded body, a sheet-like laminated body, or a laminate or adhesion of these to another supporting substrate. It may be.
  • the emitter portion 22 has a higher melting point.
  • a material with a high transpiration temperature it is less likely to be damaged by electron or ion collisions.
  • various thick film forming methods such as a screen printing method, a dating method, a coating method, an electrophoresis method, an aerosol deposition method, an ion beam method, a sputtering method, Various thin film forming methods such as vacuum deposition, ion plating, chemical vapor deposition (CVD), and plating can be used.
  • the size of the thickness d (see FIG. 1) of the emitter 22 between the upper electrode 18 and the lower electrode 20 will be described.
  • the voltage between the upper electrode 18 and the lower electrode 20 (from the drive circuit 16A)
  • the upper electrode 18 is made of the following material. That is, a conductor having a low evaporation rate and a high evaporation temperature in a vacuum is preferable.
  • the sputtering rate at 600V with Ar + is 2. 0 or less
  • the temperature at which the vapor pressure 1. 3 X 10- 3 Pa is preferred instrument
  • platinum is more than 1800 K, molybdenum, tungsten, or the like corresponds to this.
  • it is composed of a conductor having resistance to a high-temperature oxidizing atmosphere, such as a simple metal, an alloy, a mixture of insulating ceramics and a simple metal, a mixture of insulating ceramics and an alloy, and preferably platinum, iridium.
  • It is composed of refractory precious metals such as silver, palladium, rhodium, molybdenum, etc., silver-palladium, silver-platinum, platinum-palladium and other cermet materials of platinum and ceramic materials. More preferably, it is composed of a material mainly composed of platinum or a platinum-based alloy.
  • the electrode carbon or graphite-based materials such as diamond thin film, diamond-like carbon, and carbon nanotubes are also preferably used. The ratio of ceramic material added to the electrode material is 5-30% by volume. The degree is preferred.
  • an organic metal paste capable of obtaining a thin film after firing such as a platinum resinate paste.
  • the upper electrode 18 is made of the above-described materials using various thick film forming methods such as screen printing, spraying, coating, dubbing, coating, and electrophoresis, sputtering, ion beam, and vacuum deposition. , Ion plating, chemical vapor deposition (CVD), and various other thin film formation methods such as plating, can be formed according to a normal film formation method, preferably the former thick film formation method .
  • the planar shape of the upper electrode 18 may be an elliptical shape as shown in FIG. 2A, or may be a ring shape like the electron-emitting device 12Aa according to the first modification shown in FIG. 2B. . Or, it may be comb-like like the electron-emitting device 12Ab according to the second modification shown in FIG.
  • the triple point of the upper electrode 18Z emitter 22Z vacuum which is also the electric field concentration point A, can be increased, and the electron emission efficiency can be improved.
  • the thickness tc (see FIG. 1) of the upper electrode 18 is preferably 20 m or less, and more preferably 5 m or less. Therefore, the thickness tc of the upper electrode 18 may be less than lOOnm. When the thickness tc of the upper electrode 18 is extremely thin (10 nm or less), the interfacial force electrons between the upper electrode 18 and the emitter 22 are emitted, and the electron emission efficiency can be further improved. .
  • the lower electrode 20 is formed by the same material and method as the upper electrode 18, but is preferably formed by the thick film forming method.
  • the thickness of the lower electrode 20 is also preferably 20 m or less, and preferably 5 ⁇ m or less.
  • a heat treatment is performed each time the emitter section 22, the upper electrode 18, and the lower electrode 20 are formed, whereby an integrated structure can be obtained.
  • a heat treatment (firing process) for integration may not be required. Sometimes.
  • the temperature related to the firing treatment for integrating the emitter section 22, the upper electrode 18 and the lower electrode 20 together is in the range of 500-1400 ° C, preferably in the range of 1000-1400 ° C. It is good to do. Further, when the film-like emitter 22 is heat-treated, the firing process can be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the composition of the emitter 22 is not unstable at high temperatures. I like it.
  • a method may be employed in which the emitter portion 22 is covered with an appropriate member and the surface of the emitter portion 22 is not directly exposed to the firing atmosphere.
  • the drive voltage Va output from the drive circuit 16A has a period T1 during which a voltage Val is output in which the potential of the upper electrode 18 is higher than the potential of the lower electrode 20, and the potential of the upper electrode 18
  • the period T2 during which a voltage Va2 lower than the potential of the lower electrode 20 is output is repeated.
  • voltage Va2 output in period T2 is referred to as drive pulse Pd.
  • the period T 1 is a period in which the voltage Val is applied between the upper electrode 18 and the lower electrode 20 to polarize the emitter section 22.
  • the voltage Val may be a DC voltage as shown in FIG. 4, but one pulse voltage or a pulse voltage may be applied continuously several times.
  • the period T1 is preferably longer than the period T2 in order to sufficiently perform the polarization process.
  • the period T1 is preferably 100 seconds or longer. This is because the absolute value of the voltage Val for polarization is set smaller than the absolute value of the voltage Va2 for the purpose of preventing power consumption when the voltage Va 1 is applied and damage to the upper electrode 18. is there.
  • the voltages Val and Va2 are voltage levels that can positively and negatively polarize each other.
  • the absolute values of Val and Va2 are preferably not less than the coercive voltage.
  • the emitter 22 and the vacuum triple point A are provided as in this embodiment, primary electrons are extracted from the vicinity of the triple point A in the upper electrode 18, The primary electrons extracted from the triple point A collide with the emitter section 22, and secondary electrons are emitted from the emitter section 22.
  • the thickness of the upper electrode 18 is extremely thin (1 lOnm), electrons are also emitted from the interface force between the upper electrode 18 and the emitter 22.
  • a local force sword is formed in the vicinity of the interface with the emitter portion 22 in the upper electrode 18, and + of the dipole that is charged in a portion in the vicinity of the upper electrode 18 in the emitter portion 22.
  • the pole becomes a local anode and electrons are extracted from the upper electrode 18, and some of the extracted electrons are guided to the collector electrode 32 (see FIG. 1) to excite the phosphor 34.
  • the collector electrode 32 see FIG. 1 to excite the phosphor 34.
  • the collector electrode 32 see FIG. 1
  • the secondary electron emission distribution will be described with reference to FIG.
  • the majority of secondary electrons have almost zero energy, and when they are released into the surface force of the emitter 22 in a vacuum, they move only according to the surrounding electric field distribution.
  • the secondary electrons are accelerated according to the surrounding electric field distribution, with the initial force being almost O (mZsec). Therefore, as shown in FIG. 1, if an electric field Ea is generated between the emitter 22 and the collector electrode 32, the secondary electrons have their emission trajectory determined along the electric field Ea. . That is, an electron source with high straightness can be realized.
  • Such secondary electrons with a small initial velocity are electrons in the solid that have jumped out of the emitter 22 by obtaining energy from the Coulomb collision of the primary electrons.
  • Secondary electrons are emitted.
  • the secondary electrons are those in which the primary electrons emitted from the upper electrode 18 are scattered near the surface of the emitter section 22 (reflected electrons). As described in this specification, the secondary electrons are defined to include the reflected electron cathode electrons.
  • the thickness of the upper electrode 18 is extremely thin (one lOnm)
  • the primary electrons emitted from the upper electrode 18 are reflected at the interface between the upper electrode 18 and the emitter 22 and directed to the collector electrode 32. It will be.
  • the electric field strength E at the electric field concentration point A is expressed as a local anomaly.
  • V (la, lk) / d where V (la, lk) is the potential difference between the power and local force swords, and d is the distance between the local anode and the local cathode. There is. In this case, the local key
  • the constituent atoms of the emitter section 22 that are evaporated and floated by Joule heat are ionized into positive ions and electrons by the emitted electrons.
  • the generated electrons further ionize the constituent atoms of the emitter section 22 and the like, so that the number of electrons increases exponentially, and when this proceeds and the electrons and positive ions are neutral, local plasma is generated. Secondary electrons may also promote the ionization. It is conceivable that the positive electrode generated by the ionization collides with, for example, the upper electrode 18 to damage the upper electrode 18.
  • the dielectric breakdown voltage of the emitter portion 22 has at least lOkVZmm.
  • the thickness d of the emitter 22 is set to 20 m, for example, even if a drive voltage of ⁇ 100 V is applied between the upper electrode 18 and the lower electrode 20, the emitter 22 will not break down. Absent.
  • the emitter 22 is made of a dielectric having a high evaporation temperature in vacuum.
  • the emitter 22 may be made of BaTiO or the like not containing Pb. This
  • the constituent atoms of the mitter section 22 are evaporated by Joule heat, which can hinder the promotion of ionization by electrons. This is effective in protecting the surface of the emitter portion 22.
  • the pattern shape and potential of the collector electrode 32 are appropriately changed, or a control electrode (not shown) is disposed between the emitter portion 22 and the collector electrode 32, whereby the emitter electrode 22 and the collector electrode 32 are arranged.
  • the secondary electron emission trajectory is controlled by arbitrarily setting the electric field distribution of It becomes easy to control, and the convergence, expansion and deformation of the electron beam diameter are also facilitated.
  • the life of the light source 10A using the electron-emitting device 12A is extended and the reliability is improved. Can be planned.
  • the plurality of electron-emitting devices 12A are arranged two-dimensionally, a surface light source capable of extending the life and improving the reliability is realized. Will be.
  • the surface light source may always emit the entire surface, unlike the display, so that it is not necessary to perform complicated driving such as row scanning. Static drive is sufficient. Further, since it is not necessary to control the diameter of the light emission spot by electron emission, there is no need to install a control electrode or the like that functions as a focus lens, for example, between the electron-emitting device and the phosphor. This leads to simplification of the mechanical configuration as well as the circuit configuration.
  • the display needs to handle a data signal that changes at high speed according to the image signal.
  • the drive voltage has a complex waveform modulated according to the gradation.
  • a surface light source does not need to handle a data signal that changes at a high speed in accordance with an image signal, so a simple waveform (a waveform with a constant pulse period and pulse width) can be used as a drive voltage.
  • a power recovery circuit (described later) is connected to the surface light source, it is possible to recover almost 100% of the drive voltage as long as the circuit constants and circuit switching timing of the power recovery circuit can be set with high accuracy. It becomes.
  • the phosphor 34 may be formed on the back surface of the transparent plate 30, and the collector electrode 32 may be formed so as to cover the phosphor 34. .
  • the collector electrode 32 functions as a metal back.
  • the secondary electrons emitted from the emitter 22 penetrate the collector electrode 32 and enter the phosphor 34 to excite the phosphor 34.
  • the collector electrode 32 is thick enough to allow secondary electrons to pass through, and is preferably 100 nm or less. As the kinetic energy of the secondary electrons increases, the collector electrode 32 can be made thicker.
  • the collector electrode 32 reflects the light emitted from the phosphor 34, and the light emitted from the phosphor 34 can be efficiently emitted to the transparent plate 30 side (light emitting surface side).
  • a phosphor 34 is formed on the transparent plate 30, and the light emitting unit 14A having a plurality of electron-emitting devices 12A is formed.
  • mercury particles 40 may be enclosed in the atmosphere between the phosphor 34 and the phosphor 34.
  • some of the secondary electrons emitted from the electron-emitting device 12A collide with the mercury particles 40, and the mercury particles 40 are excited to emit ultraviolet rays 42.
  • the phosphor 34 is excited and embodied as phosphor emission to the outside.
  • the drive circuit 16A includes a timing generation circuit 44 and a drive voltage generation circuit 46, as shown in FIG.
  • the timing generation circuit 44 generates and outputs a timing pulse Pt for defining the output timing of the drive pulse Pd based on the control signal Sc indicating the lighting Z extinction and the clock Pc. Specifically, for example, as shown in FIG. 13A, the timing generation circuit 44 starts counting the clock Pc (see FIG. 13B) from the time when the control signal Sc becomes high level (level indicating lighting), As shown in FIG. 13C, a high-level timing pulse Pt is repeatedly generated and output during a period T2 corresponding to m clocks and during a period T1 corresponding to n clocks. This timing pulse Pt is continuously output only during the period when the control signal Sc is turned on (lighting period Ts). In the period during which the control signal Sc is at a low level (level indicating turn-off), that is, the turn-off period Tn, only the low-level signal is output from the timing generation circuit 44.
  • the drive voltage generation circuit 46 is a drive to be applied between the upper electrode 18 and the lower electrode 20 of each electron-emitting device 12A based on the timing pulse Pt from the timing generation circuit 44. Generate and output voltage Va. Specifically, as shown in FIG. 13D, the drive voltage generation circuit 46 outputs the voltage Val during the period T1 when the output of the timing generation circuit 44 is at a low level, and outputs the voltage Val during the period when the output of the timing generation circuit 44 is at a high level. Output voltage Va2 to T2. That is, the drive voltage Va output from the drive voltage generation circuit 46 has a waveform in which the drive pulse Pd appears continuously in synchronization with the timing pulse Pt of the timing generation circuit 44.
  • a power recovery circuit 50 is connected in addition to the timing generation circuit 44 and the drive voltage generation circuit 46 described above.
  • all the electron-emitting devices 12A arranged in the light emitting portion 14A are representatively shown as one capacitor C. Therefore, one electrode of the capacitor C indicates the upper electrode 18 of all the electron-emitting devices 12A, and the other electrode of the capacitor C indicates the lower electrode 20 of all the electron-emitting devices 12A.
  • a buffer capacitor Cf and a first series circuit 52 are connected in parallel between both electrodes (upper electrode 18 and lower electrode 20) of the capacitor C, respectively.
  • the second series circuit 54 is connected between the capacitor C and the buffer capacitor Cf.
  • the force is such that one buffer capacitor Cf is connected to one capacitor C. Not limited to this, two or more buffer capacitors are used for one capacitor C.
  • the number of Cf capacitors that can be connected to Cf is arbitrary.
  • the first series circuit 52 is configured by connecting a first switching circuit SW1, a current suppression resistor r, and a positive power source 56 (voltage Val) in series.
  • the second switching circuit SW2 and inductor 58 (inductance L) are connected in series. Yes.
  • the drive voltage generation circuit 46 generates control signals Scl and Sc2 for controlling the first and second switching circuits SW1 and SW2 based on the timing norse Pt from the timing generation circuit 44, and Output.
  • the first switching circuit SW1 is turned off and the second switching circuit SW2 is turned on by the control of the drive voltage generation circuit 46. It is said.
  • the sine wave oscillation of the inductor 58 and the capacitor C is started, and the resonant attenuation of the voltage across the capacitor C is started.
  • the charge accumulated in the capacitor C is collected by the buffer capacitor Cf.
  • the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46.
  • sinusoidal oscillation between the inductor 62 and the capacitor C is started, and resonance amplification of the voltage across the capacitor C is started.
  • the charge accumulated in the buffer capacitor Cf is charged into the capacitor C.
  • the power recovery circuit 50 By connecting the power recovery circuit 50 to the drive circuit 16A, it is possible to recover almost 100% of the drive voltage Va, which is advantageous in reducing power consumption.
  • the first series circuit 52 is provided, and the voltage across the capacitor C is forcibly swung to the voltage Val at a predetermined timing, so that the drive voltage associated with the power consumption by the inductor 58 is reduced. Attenuation can be avoided.
  • the voltage across the capacitor C is set to the voltage Val, and after that, only the ONZOFF operation in the second switching circuit SW2, the charge / discharge in the capacitor C and the buffer capacitor Cf Let's charge and discharge the battery alternately.
  • the light source 10A applies the driving voltage Va between the upper electrode 18 and the lower electrode 20 of all the electron-emitting devices 12A, so that the power of the light emitting unit 14A is also increased.
  • the light source 14A is divided into two groups (first and second groups G1 and G2) as in the light source lOAc according to the third modification shown in FIG. ),
  • the electron-emitting devices 12A included in the first group G1 emit light
  • the power of the electron-emitting devices 12A included in the first group G1 is collected in the electron-emitting devices 12A included in the second group G2.
  • the electron-emitting devices 12A included in the second group G2 emit light
  • the electron-emitting devices 12A included in the first group G1 The electric power of the electron-emitting devices 12A included in the second group G2 may be recovered.
  • the electron-emitting device 12A included in the first group G1 is typically shown as a capacitor C1
  • the electron-emitting device 12A included in the second group G2 is shown as a capacitor C2.
  • the drive circuit 16A may be a capacitor C1 instead of the capacitor C and a capacitor C2 instead of the notfa capacitor Cf.
  • the operation of the drive circuit 16A will be described with reference to the waveform diagram of FIG. First, before the lighting period Ts starts, the first switching circuit SW1 is turned on in advance and the second switching circuit SW2 is turned off in advance, and the voltage across the capacitor C1 is almost the same voltage as the voltage Val of the positive power supply 56. It has become.
  • the first switching circuit SW1 is turned OFF and the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46. It is said. Thereby, in the capacitor C1, the sinusoidal oscillation of the inductor 58 and the capacitor C1 is started, and the resonance attenuation of the voltage across the capacitor C1 is started. At this time, the electric charge accumulated in the capacitor C1 is recovered by the capacitor C2.
  • the sinusoidal oscillation of the inductor 58 and the capacitor C2 is started, and the resonance voltage of the both-end voltage in the capacitor C2 is started.
  • the charge stored in the capacitor C1 is charged to the capacitor C2.
  • the second switching circuit is controlled by the control of the drive voltage generation circuit 46.
  • SW2 is turned off, and the system of capacitor C1 and capacitor C2 is in a high impedance state. Therefore, the voltage Va2 is maintained in the capacitor C1 after this time t2 until the end time t3 of the period T2, and the voltage Val is maintained in the capacitor C2.
  • each of the members belonging to the first group G1 Secondary electrons are emitted from the emitter 22 of the electron emitter 12A. Due to this electron emission, light is emitted through the region of the transparent plate 30 corresponding to the first group G1.
  • the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46.
  • sinusoidal oscillation between the inductor 62 and the capacitor C1 is started, and resonance amplification of the voltage across the capacitor C1 is started.
  • the charge accumulated in the buffer capacitor Cf is charged into the capacitor C.
  • the sinusoidal oscillation of the inductor 58 and the capacitor C2 is started at the time point t3, and the resonant attenuation of the voltage across the capacitor C2 is started. At this time, the charge stored in the capacitor C2 is collected by the capacitor C1.
  • the second switching circuit SW2 is controlled by the drive voltage generation circuit 46. Is turned OFF, and the first switching circuit SW1 is turned ON. Therefore, the voltage Val is maintained in the capacitor C1 after this time t4 until the start time t2 of the next period T2, and the voltage Va2 is maintained in the capacitor C2.
  • each electron-emitting device 12A belonging to the second group G2 Secondary electrons are emitted from the emitter 22. Due to this electron emission, light is emitted through the region of the transparent plate 30 corresponding to the second group G2.
  • Time t3 force is also in period T1.
  • This period T1 is a preparation period for the next electron emission in the capacitor C1, but when viewed from the capacitor C2, it is a period T2 related to the electron emission.
  • the electron emission in each electron-emitting device 12A in the first group G1 and the second group G2 Electron emission from each electron-emitting device 12A is performed alternately. Accordingly, by appropriately setting the period T1 or the period T2, the light emission through the entire surface of the transparent plate 30 is maintained over the lighting period Ts over the four powers.
  • the period T1 or the period T2 may be intentionally set to be long so that the distinction between the light emission in the first group G1 and the light emission in the second group G2 can be recognized by the human eye!
  • the so-called buffer capacitor for recovering the power of the electron-emitting device 12A included in the group other than the loop that performs the light-emitting operation Since it is also used as Cf, it is possible to effectively reduce the mounting area and power consumption without the need for a separate buffer capacitor Cf.
  • the electron-emitting devices 12A of the first group G1 and the electron-emitting devices 12A of the second group G2 are dispersed in a certain unit, it is possible to always obtain apparently uniform surface light emission. I'll do it.
  • a modulation circuit 60 may be connected.
  • the modulation circuit 60 is a circuit that controls the amount of electron emission of each electron-emitting device 12A according to a dimming signal Sh from a dimming volume (not shown) installed outside.
  • the modulation circuit 60 has four modulation methods. As shown in FIG. 19A, the first modulation method modulates the pulse width of the voltage Va2 as shown in FIG. 19B and FIG. 19C based on the level (voltage level, etc.) of the dimming signal Sh. It is a method. In this case, the period T2 itself may be modulated as shown in FIG. 19B, or the period T2 is constant and the voltage Va2 application period ⁇ a is modulated as shown in FIG. 19C. Also good.
  • the modulation method in FIG. 19C utilizes the fact that the pulse width of the voltage Va2 and the luminance have a linear relationship as shown in FIG.
  • the luminance can be changed from 0 to about 1020 (cdZm2). Therefore, if the pulse width of the voltage Va2 is controlled, high-definition gradation expression can be realized with inexpensive digital control. Can do.
  • the second modulation method is a method of controlling the collector voltage Vc, and utilizes the fact that the collector voltage Vc and the luminance are linear as shown in FIG. By changing the collector voltage Vc from 4 kV to 7 kV, the luminance can be changed from 0 to 600 (cd / m2).
  • the third modulation method is a method of controlling the voltage Va2 (voltage level) of the drive voltage Va, and utilizes the fact that the voltage Va2 and the luminance are in a linear relationship as shown in FIG. is there. For example, by changing the voltage Va2 from about 118 V to 188 V, the luminance can be changed from 0 to 1600 (cdZm 2).
  • the fourth modulation method is a method of controlling the voltage Val of the drive voltage Va.
  • the control is difficult and the force of the force is also low. Since the analog voltage control for the voltage Val is necessary, the circuit must be devised.
  • the first modulation method that modulates the pulse width of the voltage Va2 among the first, first, and fourth modulation methods.
  • one collector electrode 32 is arranged for a plurality of electron-emitting devices 12A, and the collector electrode 32 is connected via a resistor R2.
  • the same number of collector electrodes 32 (1) as the number of columns of the light source lOAd, such as the light source lOAd according to the fourth modification shown in FIG. 32 (2), ..., 32 (N) are arranged, and each collector electrode 32 (1), 32 (2), ..., 32 (N) has resistance Rcl, Rc2, ... ⁇ ⁇ ⁇ RcN may be connected.
  • variations at the manufacturing stage for example, luminance variations for each electron-emitting device 12A, are converted into resistances Rcl, Rc2, and 32 (N) connected to the collector electrodes 32 (1), 32 (2), ..., 32 (N). ⁇ ⁇ ⁇ ⁇ Adjustable through RcN.
  • the conventional method for reducing variation is to connect a resistor for current suppression to the emitter. By doing so, the variation is reduced.
  • this method has a relationship between the current flowing through the emitter and the gate voltage.
  • the simulation must be repeated many times before the optimum resistance value for reducing the fluctuation is obtained.
  • FIG. 25 it is connected between the upper electrode 18 and a negative power source 70 for applying a negative voltage Vk (for example, the same voltage as the voltage Va2 described above) between the upper electrode 18 and the lower electrode 20.
  • Vk negative voltage
  • the resistor Rc connected between the collector electrode 32 and the bias power source 36 (bias voltage Vc).
  • the resistance Rkc indicates the resistance due to the gap between the upper electrode 18 and the collector electrode 32
  • the voltage Vkc indicates the voltage between the gaps.
  • C represents the capacitance between the upper electrode 18 and the lower electrode 20
  • the voltage Vak represents the voltage between the upper electrode 18 and the lower electrode 20.
  • the output characteristics (Vkc-Ike characteristics) of these two electron-emitting devices 12A (1) and 12A (2) are As shown in FIG. 27, when the resistances Rk and Rc do not exist when there is variation, the current fluctuation in these two electron-emitting devices 12A (1) and 12A (2) becomes ⁇ .
  • the current fluctuation at ⁇ can be reduced to ⁇ ⁇ .
  • FIG. 26 shows an equivalent circuit based on the current Ike flowing between the upper electrode 18 and the collector electrode 32 based on the configuration diagram shown in FIG.
  • Ike (Vk + Vc) / (Rc + Rkc + Rk)
  • Ig (Vg + Vk) / (Rg + Rkg + Rk)
  • a load line is drawn based on this equation, and the voltage Vg and resistance Rg that minimize the luminance variation can be determined.
  • the control current Ig and the cathode current Ik are determined, and the collector current Ic is inevitably determined.
  • the light source 10A according to the first embodiment described above has one light emitting unit 14A including all the electron-emitting devices 12A, and one drive circuit 16A is connected to the light emitting unit 14A.
  • two or more surface light source units Z1 to Z6 may be provided as in the light source lOAe according to the fifth modification of FIG. 29, two or more surface light source units Z1 to Z6 may be provided. In the example of FIG. 29, the case where six surface light source units Z1-Z6 are provided is shown. Each surface light source unit Z1-Z6 is configured by two-dimensionally arranging a plurality of electron-emitting devices 12A, and a drive circuit 16A is independently connected thereto.
  • each surface light source unit Z1-Z6 is shown to be the same, but the area of each surface light source unit Z1-Z6 may be different.
  • the first and sixth surface light source units Z1 and Z6 are respectively disposed laterally.
  • the rectangular shape has a long and long side, and the second and fifth surface light source sections are each vertically long and the long side is shorter than the first and sixth surface light source sections Z1 and Z6.
  • the case where the third and fourth surface light source parts are each horizontally long and the long side is shorter than the first and sixth surface light source parts Z1 and Z6 is shown.
  • each of the plurality of electron-emitting devices 12A included in each surface light source unit Z1-Z6 is divided into two groups (first and second In each of the surface light sources Z1 to Z6, the power of the electron-emitting devices 12A included in the first group G1 is emitted at the time of light emission of the electron-emitting devices 12A included in the first group.
  • the electron-emitting device 12A included in the second group G2 So that the power is collected in the electron-emitting device 12A included in the first group G1.
  • the six surface light source units Z1 and Z6 are divided into two groups (first and second groups G1 and G2),
  • the surface light source units Z1-Z3 related to the first group G1 emit light from the electron-emitting devices 12A.
  • the power of the electron-emitting devices 12A is used as the electron emission elements of the surface light source unit Z4-Z6 related to the second group G2.
  • the power of these electron emitters 12A is used as the electrons of the surface light source unit Z1—Z3 related to the first group G1. Let's collect it in the emitting element 12A.
  • the light source 10A has a plurality of upper electrodes 18 formed independently on the surface of one emitter section 22, and on the back surface of the emitter section 22.
  • the force in which a plurality of lower electrodes 20 are formed independently to form a plurality of electron-emitting devices 12A, and other embodiments other than those shown below are conceivable.
  • the collector electrode 32 and the phosphor 34 are not shown.
  • the light source lOAi according to the ninth modification of FIG. 33 is formed on the surface of one emitter section 22.
  • a case is shown in which a plurality of upper electrodes 18 are formed independently, and one lower electrode 20 (common lower electrode) is formed on the back surface of the emitter section 22 to form a plurality of electron-emitting devices 12A.
  • one ultrathin (one 10 nm) upper electrode 18 (common upper electrode) is formed on the surface of one emitter 22, and the emitter 22 A case is shown in which a plurality of lower electrodes 20 are formed independently on the back surface of each of the plurality of electron-emitting devices 12A.
  • the light source lOAk according to the eleventh modification example of FIG. 35 has a plurality of lower electrodes 20 formed independently on a substrate 90, and a single emitter portion 22 so as to cover these lower electrodes 20. Further, a case is shown in which a plurality of upper electrodes 18 are independently formed on the emitter section 22 to form a plurality of electron-emitting devices 12A. Each upper electrode 18 is formed on a corresponding lower electrode 20 with an emitter portion 22 interposed therebetween.
  • one lower electrode 20 is formed on a substrate 90, one emitter 22 is formed so as to cover the lower electrode 20, and A case where a plurality of upper electrodes 18 are independently formed on the portion 22 to form a plurality of electron-emitting devices 12A is shown.
  • a plurality of lower electrodes 20 are independently formed on the substrate 90, and one emitter section is formed so as to cover the plurality of lower electrodes 20.
  • 22 shows a case where a plurality of electron-emitting devices 12 A are formed by forming one ultrathin upper electrode 18 on the emitter 22.
  • FIG. 10B a light source 10B according to the second embodiment will be described with reference to FIGS. 38 to 77.
  • the electron emitter 12B of the light source 10B includes the above-described emitter unit 22, the upper electrode 18, the lower electrode 20, and the upper electrode 18 and the lower electrode 20. And a pulse generation source 100 for applying a driving voltage Va.
  • the upper electrode 18 has a plurality of through portions 102 from which the emitter portion 22 is exposed.
  • the surface of the emitter portion 22 has irregularities 104 formed by dielectric grain boundaries.
  • the through portion 102 is formed in a portion corresponding to the concave portion 106 in the dielectric grain boundary.
  • the particle size of the dielectric constituting the emitter portion 22 is preferably 0.1 m-10 m, and more preferably 2 ⁇ m-7 ⁇ m. In the example of Fig. 38, the dielectric particle size is 3 ⁇ m.
  • the surface 108 a of the upper electrode 18 facing the emitter portion 22 in the peripheral portion 108 of the penetrating portion 102 is separated from the emitter portion 22. I'm waiting. That is, in the upper electrode 18, a gap 110 is formed between the surface 108a of the peripheral portion 108 of the penetrating portion 102 facing the emitter portion 22 and the emitter portion 22, and the peripheral portion of the penetrating portion 102 in the upper electrode 18 is formed. 108 is formed in a bowl shape (flange shape). Therefore, in the following description, “the peripheral portion 108 of the through portion 102 of the upper electrode 18” is referred to as “the upper portion 108 of the upper electrode 18”. In the examples of FIGS.
  • the cross section of the protrusion 112 of the unevenness 104 of the dielectric grain boundary is shown. Typically, it is shown in a semicircular shape, but it is not limited to this shape! /.
  • the thickness t of the upper electrode 18 is set to 0.01 m ⁇ t ⁇ 10 m, and the upper surface of the emitter 22, that is, the protrusion 112 at the grain boundary of the dielectric.
  • the maximum angle 0 formed by the surface of the upper electrode 18 (which is also the inner wall surface of the recess 106) and the lower surface 108a of the flange 108 of the upper electrode 18 is set to 1 ° ⁇ 0 ⁇ 60 °.
  • the maximum distance d along the vertical direction between the surface of the convex portion 112 (the inner wall surface of the concave portion 106) and the lower surface 108a of the flange portion 108 of the upper electrode 18 at the dielectric grain boundary of the emitter portion 22 is 0 ⁇ ⁇ ⁇ 10 ⁇ m
  • the shape of the penetrating part 102 is the shape of the hole 114, for example, a circular shape, an elliptical shape, There are those that include a curved portion such as a track shape, and polygonal shapes such as a square and a triangle.
  • the hole 114 has a circular shape.
  • the average diameter of the holes 114 should be 0.1 m or more and 10 ⁇ m or less! This average diameter represents the average of the lengths of a plurality of different line segments passing through the center of the hole 114.
  • the constituent material of the emitter section 22 is the same as that in the first embodiment described above. The description is omitted.
  • various thick film forming methods such as a screen printing method, a dating method, a coating method, an electrophoresis method, an aerosol deposition method, an ion beam method, a sputtering method, a vacuum
  • various thin film forming methods such as vapor deposition, ion plating, chemical vapor deposition (CVD), and plating can be used.
  • CVD chemical vapor deposition
  • the upper electrode 18 is made of an organic metal paste that provides a thin film after firing.
  • a material such as platinum resinate paste is preferably used.
  • oxide electrodes that suppress polarization reversal fatigue such as ruthenium oxide (RuO), iridium oxide (IrO), ruthenium
  • an aggregate 118 of substances 116 for example, graphite
  • An aggregate 122 of conductive substances 120 including a substance 116 having a scale-like shape is also preferably used.
  • a plurality of penetrating portions 102 where the emitter portion 22 does not completely cover the surface of the emitter portion 22 with the aggregate 118 or the aggregate 122 are provided.
  • the part that faces is an electron emission region.
  • the upper electrode 18 is made of the above-mentioned materials using various thick film forming methods such as screen printing, spraying, coating, dubbing, coating, and electrophoresis, sputtering, ion beam, and vacuum deposition. , Ion plating, chemical vapor deposition (CVD), and various other thin film formation methods such as plating, can be formed according to a normal film formation method, preferably the former thick film formation method .
  • the lower electrode 20 is made of a conductive material, such as metal, and is made of platinum, molybdenum, tungsten, or the like.
  • conductors resistant to high-temperature oxidizing atmospheres such as simple metals, alloys, mixtures of insulating ceramics and simple metals, insulation
  • a high melting point noble metal such as platinum, iridium, palladium, rhodium, molybdenum, silver-palladium, silver-platinum, platinum, etc.
  • alloys mainly composed of alloys such as palladium and cermet materials of platinum and ceramic materials.
  • the preferred coconut paste is composed of a material mainly composed of platinum or a platinum-based alloy.
  • the lower electrode 20 may be made of carbon or graphite materials.
  • the proportion of the ceramic material added to the electrode material is preferably about 5-30% by volume. Of course, you may use the same material as the upper electrode 18 mentioned above.
  • the lower electrode 20 is preferably formed by the thick film forming method.
  • the thickness of the lower electrode 20 is preferably 20 m or less, and preferably 5 m or less.
  • An integral structure can be obtained by performing heat treatment (firing treatment) each time the emitter section 22, the upper electrode 18, and the lower electrode 20 are formed.
  • the temperature related to the firing treatment for integrating the emitter section 22, the upper electrode 18 and the lower electrode 20 is in the range of 500-1400 ° C, preferably in the range of 1000-1400 ° C. Good. Further, when the film-like emitter 22 is heat-treated, the firing process can be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the composition of the emitter 22 is not unstable at high temperatures. I like it.
  • the film that becomes the upper electrode 18 contracts from, for example, a thickness of 10 m to a thickness of 0.0 m, and a plurality of holes are formed at the same time.
  • a plurality of through portions 102 are formed in the upper electrode 18, and the peripheral portion 108 of the through portion 102 is formed in a bowl shape.
  • the film to be the upper electrode 18 may be subjected to patterning by etching (wet etching, dry etching), lift-off, or the like in advance (before firing) and then fired. In this case, as will be described later, a notch shape or a slit shape can be easily formed as the penetrating portion 102.
  • the drive voltage Va is applied between the upper electrode 18 and the lower electrode 20.
  • This drive voltage Va is, for example, Over time, the voltage level is higher or lower than the reference voltage (e.g., OV), but lower than the reference voltage! Or higher! Defined as the voltage to
  • a triple junction is formed at a contact point between the upper surface of the emitter section 22, the upper electrode 18, and the medium (for example, vacuum) around the electron-emitting device 12B.
  • the triple junction is defined as an electric field concentration portion formed by contact of the upper electrode 18, the emitter portion 22, and the vacuum.
  • the triple junction also includes a triple point where the upper electrode 18, the emitter 22 and the vacuum exist as one point.
  • the degree of vacuum in the atmosphere is preferably 10 2 ⁇ 10 ⁇ 6 Pa, more preferably 10 3 ⁇ 10 ⁇ 5 Pa.
  • the triple junction is formed at the flange portion 108 of the upper electrode 18 and the peripheral portion of the upper electrode 18. Therefore, when the drive voltage Va as described above is applied between the upper electrode 18 and the lower electrode 20, electric field concentration occurs in the triple junction described above.
  • FIG. 43 In the first output period T1 (first stage) in FIG. 43, a voltage V2 lower than the reference voltage (in this case, OV) is applied to the upper electrode 18, and a voltage VI higher than the reference voltage is applied to the lower electrode 20. Applied.
  • electric field concentration occurs in the triple junction described above, and electrons are emitted from the upper electrode 18 toward the emitter section 22.
  • the upper electrode 18 penetrates through the upper electrode 18. Electrons are accumulated in the portion exposed from the portion 102 and the portion near the peripheral edge of the upper electrode 18. That is, the emitter part 22 is charged. At this time, the upper electrode 18 functions as an electron supply source.
  • the voltage level of the drive voltage Va suddenly decreases, that is, the voltage VI higher than the reference voltage is applied to the upper electrode 18, and the lower electrode 2 0
  • a voltage V2 lower than the reference voltage is applied to the upper electrode 18
  • the electrons charged in the portion corresponding to the through-hole 102 of the upper electrode 18 and in the vicinity of the peripheral edge of the upper electrode 18 are polarized in the opposite direction. Due to the dipole of the part 22 (negative polarity appears on the surface of the emitter part 22), the part 22 is expelled from the emitter part 22, and as shown in FIG. 44, from the part where the electrons are accumulated in the emitter part 22. Electrons are emitted through the penetrating part 102. Of course, the upper electrode 18 Electrons are also emitted from the vicinity of the outer periphery of the.
  • the second electron emission method will be described.
  • a voltage V3 higher than the reference voltage is applied to the upper electrode 18, and a voltage V4 lower than the reference voltage is applied to the lower electrode 20.
  • preparation for electron emission for example, polarization in one direction of the emitter 22
  • the voltage level of the drive voltage Va changes suddenly, that is, the voltage V4 lower than the reference voltage is applied to the upper electrode 18, and the reference voltage is applied to the lower electrode 20.
  • the drive voltage Va is applied. Electric field concentration is likely to occur in the gap 110 part. This leads to high efficiency of electron emission, and can reduce the drive voltage (electron emission at a low voltage level).
  • the upper electrode 18 has the flange portion 108 formed in the peripheral portion of the penetrating portion 102. Therefore, the electric field concentration in the gap 110 portion described above. In combination with the increase in the size, electrons are likely to be emitted from the flange portion 108 of the upper electrode 18. This leads to a high output and high efficiency of electron emission, and a low drive voltage Va can be realized. As a result, for example, a second configuration in which a large number of electron-emitting devices 12B are arranged side by side. The luminance of the light source 10B according to the embodiment can be increased.
  • the first electron emission method (method of emitting electrons accumulated in the emitter unit 22) and the second electron emission method (primary electrons from the upper electrode 18 are caused to collide with the emitter unit 22 as described above.
  • the eaves 108 of the upper electrode 18 functions as a gate electrode (control electrode, focus electron lens, etc.), so that the straightness of the emitted electrons can be improved. it can. This is advantageous in reducing crosstalk when a large number of electron-emitting devices 12B are arranged to form, for example, a display electron source.
  • the upper surface of the emitter portion 22 is provided with irregularities 104 due to dielectric grain boundaries, and the upper electrode 18 corresponds to the concave portions 106 at the dielectric grain boundaries. Since the penetrating portion 102 is formed in the part, the flange portion 108 of the upper electrode 18 can be easily realized.
  • the maximum angle between the upper surface of the emitter portion 22, that is, the surface of the convex portion 112 (inner wall surface of the concave portion 106) at the dielectric grain boundary, and the lower surface 108a of the flange portion 108 of the upper electrode 18 The angle 0 is set to 1 ° ⁇ ⁇ ⁇ 60 °, and the surface of the convex portion 112 (the inner wall surface of the concave portion 106) at the dielectric grain boundary of the emitter 22 and the lower surface 108a of the flange portion 108 of the upper electrode 18 Since the maximum distance d along the vertical direction between them is set to 0 m ⁇ d ⁇ 10 m, these configurations can further increase the degree of electric field concentration in the gap 110 and reduce electron emission. High output, high efficiency, and low drive voltage can be efficiently achieved.
  • the penetrating portion 102 has the shape of the hole 114.
  • the upper electrode 18 is formed in the portion of the emitter 22 where the polarization is reversed or changed according to the drive voltage Va applied between the upper electrode 18 and the lower electrode 20 (see FIG. 38).
  • a portion (second portion) 126 corresponding to the directional force region from the inner periphery of the penetrating portion 102 to the inside of the penetrating portion 102, particularly the second portion. This portion 126 changes depending on the level of the driving voltage Va and the degree of electric field concentration.
  • the average diameter of the holes 114 is set to 0.1 l / zm or more and 10 / zm or less. The Within this range, there is almost no variation in the emission distribution of electrons emitted through the penetrating portion 102, and electrons can be efficiently emitted.
  • the average diameter of the holes 114 is less than 0.1 ⁇ m, the region for accumulating electrons becomes narrow, and the amount of electrons emitted is reduced. Of course, it is conceivable to provide a large number of holes 114, but there is a concern that the manufacturing cost increases with difficulty.
  • the average diameter of the holes 114 exceeds 10 m, the ratio (occupancy) of the portion (second portion) 126 that contributes to electron emission out of the portion exposed from the penetrating portion 102 of the emitter portion 22 decreases. Electron emission efficiency decreases.
  • the cross-sectional shape of the flange portion 108 of the upper electrode 18 may be a shape that extends horizontally along the upper surface and the lower surface, as shown in FIG. 39, or the lower surface 108a of the flange portion 108, as shown in FIG. However, the upper end of the flange 108 may be raised upward. Further, as shown in FIG. 48, the lower surface 108a of the flange portion 108 may be gradually inclined upward in accordance with the directional force at the center of the penetrating portion 102, or as shown in FIG. The lower surface 108a may be gradually inclined downward as it moves toward the center of the penetrating portion 102.
  • the example in FIG. 47 can enhance the function as a gate electrode.
  • the gap 110 is narrowed, so that electric field concentration is more likely to occur, and electron emission is enhanced. Output and high efficiency can be improved.
  • the capacitor C1 by the emitter 22 and each gap 110 are provided.
  • a plurality of capacitor Ca aggregates are formed. That is, a plurality of capacitors Ca by each gear 110 are configured as one capacitor C 2 connected in parallel to each other, and in terms of equivalent circuit, a capacitor C 1 by the emitter 22 is added to a capacitor C 2 by an aggregate. It becomes the form connected in series.
  • the capacitor C2 from the aggregate is not directly connected in series with the capacitor C2 from the aggregate, depending on the number of through-holes 102 formed in the upper electrode 18 and the overall formation area.
  • the capacitor component connected in series changes.
  • the capacitance value of the capacitor C1 by the emitter 22 is 35.4pF. Then, when the portion connected in series with the capacitor C2 by the aggregate in the capacitor C1 by the emitter section 22 is 25% of the total, the capacitance value in the portion connected in series (the capacitor C2 by the aggregate is The capacitance value including the capacitance value) is 0.805pF, and the remaining capacitance value is 26.6pF.
  • the total capacitance value is 27.5 pF. This capacitance value is 78% of the capacitance value 35.4 pF of the capacitor C1 by the emitter 22. In other words, the overall capacitance value is less than the capacitance value of the capacitor C1 by the emitter unit 22 / J.
  • the capacitance value of the capacitor Ca by the gap 110 becomes relatively small, and is applied from the partial pressure with the capacitor C1 by the emitter unit 22. Most of the voltage Va is applied to the gap 110, and in each gap 110, high output of electron emission is realized.
  • the capacitor C2 by the aggregate has a structure connected in series to the capacitor C1 by the emitter section 22, the overall capacitance value is smaller than the capacitance value of the capacitor C1 by the emitter section 22. For this reason, the electron emission has a high output, and if the overall power consumption becomes small, it is preferable to obtain characteristics.
  • FIG. 52 Three modified examples of the electron-emitting device 12B of the light source 10B according to the second embodiment described above will be described with reference to FIGS. 52 to 54.
  • FIG. 52 Three modified examples of the electron-emitting device 12B of the light source 10B according to the second embodiment described above will be described with reference to FIGS. 52 to 54.
  • the electron-emitting device 12Ba according to the first modification is different in that the shape of the penetrating portion 102, particularly the shape in view of the upper surface force, is the shape of the notch 128.
  • the shape of the notch 128, as shown in FIG. 52 a comb-shaped notch 130 in which a large number of notches 128 are continuously formed is preferable. In this case, it is advantageous in reducing variation in the emission distribution of electrons emitted through the through-hole 102 and efficiently emitting electrons.
  • Notch 1 in particular
  • the average width of 28 is preferably not less than 0 and not more than 10 m. This average width indicates the average length of a plurality of different line segments orthogonal to the center line of the notch 128.
  • the electron-emitting device 12Bb according to the second modification is different in that the shape of the penetrating portion 102, particularly, the shape seen from the top surface is the slit 132.
  • the slit 132 is a slit whose length in the major axis direction (longitudinal direction) is 10 times or more of the length in the minor axis direction (short direction). Accordingly, a shape whose length in the major axis direction (longitudinal direction) is less than 10 times the length in the minor axis direction (short direction) can be defined as the shape of the hole 114 (see FIG. 40).
  • the slit 132 includes a plurality of holes 114 connected to each other.
  • the average width of the slit 132 is preferably not less than 0 and not more than 10 m. It also has the advantage of reducing the variation in the emission distribution of electrons emitted through the through-hole 102 and efficiently emitting electrons. This average width indicates the average length of a plurality of different line segments orthogonal to the center line of the slit 132.
  • the electron-emitting device 12Bc according to the third modified example has a portion corresponding to the penetrating portion 102 on the upper surface of the emitter portion 22, for example, a concave portion 106 in a dielectric grain boundary.
  • a floating electrode 134 is present.
  • the floating electrode 134 is also an electron supply source, in the electron emission stage (the second output period T2 in the first electron emission method described above (see FIG. 43)), a large number of electrons are allowed to pass through the through-hole 102. It can be released to the outside.
  • electron emission from the floating electrode 134 may be due to electric field concentration in the triple junction of the floating electrode 134Z dielectric and vacuum.
  • the characteristics of the electron-emitting device 12B of the light source 10B according to the second embodiment in particular, the voltage charge amount characteristic (voltage unipolarization amount characteristic) will be described.
  • This electron-emitting device 12B has a reference voltage in a vacuum as shown in the characteristics of FIG.
  • the amount of positive charge and the amount of negative charge become balanced at the point p 2 of a certain negative voltage as electrons accumulate in the electron emission portion, As the negative voltage level is increased in the negative direction, the amount of accumulated electrons further increases, and as a result, the amount of negative charge is greater than the amount of positive charge. At point p3, the accumulation of electrons becomes saturated.
  • the amount of negative charge here is the sum of the amount of electrons remaining accumulated and the amount of negative charge of the dipole whose emitter 22 has undergone polarization inversion.
  • V3 is the voltage at which electrons are accumulated and saturated
  • V4 is the voltage at which electron emission starts
  • FIG. 55 the characteristic of FIG. 55 will be described from the standpoint of the voltage-one-polarization amount characteristic.
  • the description will be made on the assumption that the emitter portion 22 is polarized in the negative direction so that, for example, the negative pole of the dipole faces the upper surface of the emitter portion 22 (see FIG. 56A).
  • electrons are emitted (internally emitted) from the upper electrode 18 toward a portion of the emitter portion 22 exposed from the penetrating portion 102 of the upper electrode 18. Then, at point p3 in FIG. 55, the accumulated state of electrons is saturated.
  • Characteristic portions of the characteristics of the electron-emitting device 12B are as follows.
  • the electron-emitting device 12B since the electron-emitting device 12B has the above-described characteristics, the electron-emitting device 12B includes a plurality of electron-emitting devices 12B arranged according to a plurality of pixels, and emits electrons from each electron-emitting device 12B.
  • the present invention can be easily applied to the light source 10B according to the second embodiment that emits light.
  • the light source 10B according to the second embodiment is a light source conforming to a display that displays an image such as a backlight for a liquid crystal display, and includes a large number of electron-emitting devices as shown in FIG. 12B includes, for example, light emitting units 14B arranged in a matrix or staggered manner corresponding to light emitting elements such as pixels, and a drive circuit 16B for driving the light emitting units 14B.
  • one electron-emitting device 12B may be assigned to one light-emitting device, or a plurality of electron-emitting devices 12B may be assigned to one light-emitting device.
  • the case where one electron-emitting device 12B is assigned to each light-emitting device will be described.
  • the drive circuit 16B is provided with a plurality of row selection lines 144 for selecting a row for the light emitting unit 14B, and a plurality of signals for supplying the data signal Sd to the light emitting unit 14B.
  • Wire 146 is wired.
  • the drive circuit 16B selectively supplies a selection signal Ss to the row selection line 144, for example, a row selection circuit 148 that sequentially selects the electron-emitting devices 12B in units of one row, and a signal line 14 6
  • the signal supply circuit 150 that outputs the data signal Sd in parallel and supplies the data signal Sd to the row selected by the row selection circuit 148 (selected row), and the input control signal Sv (video signal, etc.)
  • a signal control circuit 152 for controlling the row selection circuit 148 and the signal supply circuit 150 based on the synchronization signal Sc.
  • a power supply circuit 154 (for example, 50 V and OV) is connected to the row selection circuit 148 and the signal supply circuit 150, and in particular, a pulse power supply is connected between the negative line between the row selection circuit 148 and the power supply circuit 154 and GND (ground). 156 is connected.
  • the pulse power source 156 outputs a pulsed voltage waveform having a reference voltage (for example, OV) in a charge accumulation period Td, which will be described later, and a voltage (for example, 400 V) in the light emission period Th.
  • the row selection circuit 148 In the charge accumulation period Td, the row selection circuit 148 outputs the selection signal Ss to the selected row and outputs the non-selection signal Sn to the non-selected row. In addition, the row selection circuit 148 outputs a constant voltage (for example, ⁇ 350 V) in which the power supply voltage (for example, 50 V) from the power supply circuit 154 and the voltage from the pulse power supply 156 (for example, ⁇ 400 V) are added during the light emission period Th. .
  • a constant voltage for example, ⁇ 350 V
  • the power supply voltage for example, 50 V
  • the pulse power supply 156 for example, ⁇ 400 V
  • the signal supply circuit 150 includes a pulse generation circuit 158 and an amplitude modulation circuit 160.
  • the pulse generation circuit 158 generates and outputs a pulse signal Sp having a constant pulse period and a constant amplitude (for example, 50 V) in the charge accumulation period Td, and outputs a reference voltage (for example, 0 V) in the light emission period Th. To do.
  • the amplitude modulation circuit 160 modulates the amplitude of the pulse signal Sp from the pulse generation circuit 158 according to the luminance level of the light emitting element related to the selected row, and each of the light emitting element related to the selected row.
  • the data signal Sd is output, and the reference voltage from the pulse generation circuit 158 is output as it is during the light emission period Th.
  • the timing control and the supply of the luminance levels of the selected light emitting elements to the amplitude modulation circuit 160 are performed through the signal supply circuit 150.
  • the amplitude of the pulse signal Sp when the luminance level is low, the amplitude of the pulse signal Sp is set to the low level Vsl (see FIG. 59A), and when the luminance level is medium, When the amplitude of the pulse signal Sp is medium level Vsm (see Figure 59B) and the luminance level is high In this case, the amplitude of the pulse signal Sp is set to the high level Vsh (see Fig. 59C).
  • the pulse signal Sp is amplitude-modulated, for example, in 128 steps or 256 steps depending on the luminance level of the light emitting element.
  • the signal supply circuit 150a includes a pulse generation circuit 162 and a pulse width modulation circuit 164 as shown in FIG.
  • the pulse generator 162 is a pulse whose voltage rises continuously in the voltage waveform applied to the electron-emitting device 12B (shown by a solid line in FIGS. 61A to 61C) during the charge accumulation period Td. Generates and outputs the signal Spa (indicated by a broken line in FIGS. 61A and 61C), and outputs a reference voltage during the light emission period Th.
  • the pulse width modulation circuit 164 modulates the pulse width Wp (see FIGS.
  • the pulse signal Spa from the pulse generation circuit 162 according to the luminance level of the light emitting element for the selected row.
  • the data signal Sd of the light emitting element for each selected row is output.
  • the reference voltage from the pulse generation circuit 162 is output as it is. Also in this case, the timing control and the supply of the luminance levels of the selected light emitting elements to the pulse width modulation circuit 164 are performed through the signal supply circuit 150a.
  • the pulse width Wp of the pulse signal Spa when the luminance level is low, the pulse width Wp of the pulse signal Spa is shortened and the substantial amplitude is set to the low level Vsl (FIG. 61A). If the brightness level is medium, the pulse width Wp of the pulse signal Spa is set to the medium length, the actual amplitude is set to the medium level Vsm (see Fig. 61B), and the brightness level is high. Then, the pulse width Wp of the pulse signal Spa is lengthened and the substantial amplitude is set to the high level Vsh (see Fig. 61C).
  • the pulse width of the pulse signal Spa is modulated in 128 steps or 256 steps, for example, depending on the luminance level of the light emitting element.
  • the amount of accumulated electrons is moderate as shown in FIG.62B, and at the negative voltage level Vsh shown in FIGS.59C and 61C, it is shown in FIG. As shown, the amount of accumulated electrons is large and almost saturated.
  • this electron-emitting device 12B is used as a light-emitting device of the light source 10B, as shown in FIG. 63, a transparent plate 166 made of, for example, glass or acrylic is disposed above the upper electrode 18, A collector electrode 168 made of, for example, a transparent electrode is disposed on the back surface (the surface facing the upper electrode 18) of the transparent plate 166, and a phosphor 170 is applied to the collector electrode 168. A bias voltage source 172 (collector voltage Vc) is connected to the collector electrode 168 via a resistor.
  • the electron emitter 12B is naturally disposed in the vacuum space.
  • the degree of vacuum in the atmosphere is preferably 10 2 ⁇ 10 ⁇ 6 Pa, more preferably 10 ⁇ 3 ⁇ 10 ⁇ 5 Pa.
  • the force is such that the collector electrode 168 is formed on the back surface of the transparent plate 166, and the phosphor 170 is formed on the surface of the collector electrode 168 (the surface facing the upper electrode 18). 64, a phosphor 170 is formed on the back surface of the transparent plate 166, and the phosphor 170 is covered. So that the collector electrode 168 may be formed!
  • the collector electrode 168 reflects the light emitted from the phosphor 170, and the light emitted from the phosphor 170 can be efficiently emitted to the transparent plate 166 side (light emitting surface side).
  • the electron emission state of the electron-emitting device 12B is observed. That is, as shown in FIG. 65A, a write pulse Pw having a voltage of 70V is applied to the electron-emitting device 12B to accumulate electrons in the electron-emitting device 12B, and then a lighting pulse having a voltage of 280V. Ph was applied to emit electrons. The electron emission state was measured by detecting the light emission of the phosphor 170 with a light receiving element (photodiode). The detected waveform is shown in Figure 65B. The duty ratio of the write pulse Pw and the lighting pulse Ph was 50%.
  • the second experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the amplitude of the write pulse Pw shown in FIG.
  • the change in the amount of emitted electrons is detected by the light receiving element (photodiode) as in the first experimental example. And measured.
  • the experimental results are shown in FIG.
  • the solid line A shows the characteristics when the amplitude of the lighting pulse Ph is 200V and the amplitude of the write pulse Pw is changed from 10V to 80V
  • the solid line B shows the amplitude of the lighting pulse Ph is 350V. The characteristics when the amplitude of the write pulse Pw is changed from 10V to –80V are shown.
  • the write pulse Pw when the write pulse Pw is changed from 20V to 40V, it can be seen that the light emission luminance changes almost linearly.
  • the amplitude of the lighting pulse Ph is 350 V and when it is 200 V, the dynamic range of the emission luminance change with respect to the write pulse Pw is wider in the case of 350 V. It turns out to be advantageous.
  • the contrast of the display can be improved. This tendency can be seen in the range until the light emission brightness is saturated with respect to the amplitude setting of the lighting pulse Ph, and the force that seems to be more advantageous as the amplitude of the lighting pulse Ph is increased. In view of this, it is preferable to set the optimum value.
  • the third experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the amplitude of the lighting pulse Ph shown in Fig. 66.
  • the change in the amount of emitted electrons was measured by detecting the light emission of phosphor 170 with a light receiving element (photodiode), as in the first experimental example.
  • the experimental results are shown in FIG.
  • the solid line C shows the characteristics when the amplitude of the write pulse Pw is 40 V and the amplitude of the lighting pulse Ph is changed from 50 V to 400 V
  • the solid line D is the amplitude of the write pulse Pw. Shows the characteristics when the lighting pulse Ph amplitude is changed from 50V to 400V.
  • the fourth experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the level of the collector voltage Vc shown in Fig. 63 or Fig. 64.
  • the change in the amount of emitted electrons was measured by detecting the light emission of the phosphor 170 with a light receiving element (photodiode), as in the first experimental example.
  • Figure 69 shows the experimental results.
  • solid line E shows the characteristics when the level of collector voltage Vc is 3 kV and the amplitude of lighting pulse Ph is changed from 80 V to 500 V
  • solid line F is the level of collector voltage Vc. The characteristics when the amplitude of the lighting pulse Ph is changed from 80V to 500V are shown.
  • the dynamic range of the emission luminance change with respect to the lighting pulse Ph is wider than when the collector voltage Vc is 7 kV and the force is 3 kV. It can be seen that it is advantageous in improving the contrast when applied. This tendency seems to be more advantageous as the level of the collector voltage Vc increases, but in this case as well, it is preferable to set the optimum value in relation to the withstand voltage and power consumption of the signal transmission system.
  • FIG. 70 typically shows the operation of pixels in 1 row and 1 column, 2 rows and 1 column, and n rows and 1 column.
  • the electron-emitting device 12B used here has a coercive voltage vl at point p2 in FIG. 55 of, for example, 20 V, a coercive voltage v2 at point p5 of +70 V, a voltage v3 at point p3 of ⁇ 50 V, and a voltage at point p4.
  • v4 has the characteristic of + 50V.
  • one charge accumulation period Td and one light emission period Th are included in the one frame.
  • One charge accumulation period Td includes n selection periods Ts. Since each selection period Ts is the selection period Ts of the corresponding row, it does not correspond !, and nl rows are the non-selection period Tn. [0278] Then, in this driving method, all the electron-emitting devices 12B are scanned during the charge accumulation period Td, and light emission corresponding to each of the plurality of electron-emitting devices 12B corresponding to the ON target (light-emitting target) pixels is performed.
  • an amount of electric charges (electrons) corresponding to the luminance level of the light emitting element corresponding to each of the plurality of electron emitting elements 12B corresponding to the light emitting element to be turned on is accumulated.
  • a plurality of electron-emitting devices corresponding to the light-emitting devices to be turned on by applying a constant voltage to all the electron-emitting devices 12 B 1 2B brightness levels of the corresponding light-emitting devices The amount of electrons corresponding to the amount of emitted light is emitted, and the light emitting element to be turned on emits light.
  • a selection signal Ss of 50 V is supplied to the row selection line 144 of the first row, and the other For example, a non-selection signal Sn of 0 V is supplied to the row selection line 144 of the row.
  • the voltage of the data signal Sd supplied to the signal line 146 of the light emitting element to be turned ON (light emission) is in the range of 0 V or more and 30 V or less, and corresponds to each.
  • the voltage corresponds to the luminance level of the light emitting element. If the luminance level is maximum, it will be 0V.
  • the modulation according to the luminance level of the data signal Sd is performed through the amplitude modulation circuit 160 shown in FIG. 58 and the pulse width modulation circuit 164 shown in FIG.
  • the voltage of the data signal Sd supplied to the electron-emitting device 12B corresponding to the light-emitting device indicating OFF (quenching) is, for example, 50 V, and thus the electron corresponding to the light-emitting device to be turned off. 0V is applied to the emitting element 12B, which is in the state of the point pi in the characteristic of FIG. 55, and no electrons are stored.
  • the 50V selection signal Ss is supplied to the row selection line 144 of the second row, and the OV non-selection signal Sn is supplied to the row selection line 144 of the other rows. Also in this case, a voltage of 50 V or more and 20 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to the light emitting device to be turned on (light emission) according to the luminance level. .
  • a voltage of 0 V or more and 50 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron emitting device 12B corresponding to the light emitting device in the first row in the non-selected state. Since the voltage does not reach point 4 in the characteristics of Fig. 55, electrons are emitted from the electron-emitting device 12B corresponding to the light-emitting device that should be turned on (emission) in the first row. There is no. In other words, when the light-emitting elements in the first row in the non-selected state are affected by the data signal Sd supplied to the pixels in the second row in the selected state, it is not possible.
  • the 50V selection signal Ss is supplied to the row selection line 144 of the n-th row, and the 0V non-selection signal is supplied to the row selection line 144 of the other rows. Sn is supplied. Also in this case, a voltage of 50V or more and ⁇ 20V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to the light emitting device to be turned ON (light emission) according to the luminance level.
  • a voltage of 0 V or more and 50 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to each of the light-emitting elements in one row and one (n ⁇ 1) row in the non-selected state.
  • electrons are not emitted from the electron-emitting devices 12B corresponding to the light-emitting devices that should be turned ON (light-emitting) among the non-selected light-emitting devices.
  • the light emission period Th starts when the selection period Ts of the n-th row has passed.
  • a reference voltage for example, 0 V
  • a voltage 350 V
  • Pulse power supply 156-400V + row selection circuit 148 power supply voltage 50V is applied.
  • a high voltage (+350 V) is applied between the upper electrode 18 and the lower electrode 20 of the all-electron emitting device 12B.
  • All the electron-emitting devices 12B are in the state of the characteristic point p6 in FIG. 55, and as shown in FIG. 57C, electrons are transmitted from the portion where the electrons are accumulated in the emitter portion 22 through the penetrating portion 102. Released. Of course, electrons are also emitted from the vicinity of the outer peripheral portion of the upper electrode 18.
  • electrons are emitted from the electron-emitting device 12B corresponding to the light-emitting device that should be turned ON (light emission).
  • the emitted and emitted electrons are guided to the collector electrode 168 corresponding to these electron-emitting devices 12B, and the corresponding phosphor 170 is excited to emit light. This emitted light is emitted outward through the surface of the transparent plate 166.
  • a plurality of electron-emitting devices corresponding to the light-emitting devices to be turned on by accumulating an amount of charge corresponding to the luminance level of the light-emitting device and applying a constant voltage to all the electron-emitting devices 12B in the next light-emitting period Th It becomes possible to emit an amount of electrons corresponding to the luminance level of the corresponding light emitting element from 12B to emit the light emitting element to be turned on.
  • the electron-emitting devices 12B are arranged in a matrix, and the electron-emitting devices 12B are selected in units of one row in synchronization with the horizontal scanning period.
  • the data signal Sd corresponding to the luminance level of each light emitting element is supplied, the data signal Sd is also supplied to the non-selected light emitting elements.
  • the electron-emitting device 12B in the non-selected state is affected by the data signal Sd and emits, for example, electrons, there is a problem that luminance unevenness of the light source 10B is caused.
  • the voltage level of the data signal Sd supplied to the electron-emitting device 12B in the selected state is an arbitrary voltage from the reference voltage to the voltage V3.
  • a data signal for the non-selected electron-emitting device 12B Even with a simple voltage relationship in which a signal having a reverse polarity of Sd is supplied, the non-selected light emitting element is not affected by the data signal Sd to the selected light emitting element.
  • the electron accumulation amount of each light emitting element accumulated in the selection period Ts of each light emitting element (the amount of charge of the emitter 22 in each electron emitting element 12B) is equal to the amount of electrons emitted in the next light emitting period Th.
  • the memory effect of each light emitting element can be realized, and high brightness and high contrast can be achieved.
  • the light source 10B charges necessary for all the electron-emitting devices 12B are accumulated during the charge accumulation period Td, and all the electric charges are emitted during the subsequent light emission period Th.
  • a voltage necessary for electron emission is applied to the child emitting element 12B so that electrons are emitted from the plurality of electron emitting elements 12B corresponding to the ON light emitting elements so that the ON light emitting elements emit light. Yes.
  • the period Th during which the voltage for electron emission (emission voltage) is applied to all the electron-emitting devices 12B is naturally shorter than one frame, and the first period shown in FIGS. 65A and 65B.
  • the power consumption can be greatly increased compared to the case where charge accumulation and light emission are performed during scanning to the light emitting element because the application period of the emission voltage can be shortened so that the power of the experimental example 1 can also be understood. It can be reduced.
  • the luminance level is set in each electron-emitting device 12B. Low voltage drive of the circuit to apply a voltage according to Can be achieved.
  • the selection signal SsZ non-selection signal Sn for the data signal Sd and the charge accumulation period Td needs to be driven for each row or column.
  • the drive voltage is several Since 10 volts is sufficient, an inexpensive multi-output driver used in a fluorescent display tube or the like can be used.
  • the voltage that sufficiently discharges electrons may be higher than the drive voltage.
  • a multi-output circuit is required. No parts are required. For example, a drive circuit with only one output composed of high-voltage discrete components is sufficient, so there is an advantage that the cost is low and the circuit scale is small.
  • the drive voltage and discharge voltage can be lowered by reducing the thickness of the emitter section 22. Therefore, for example, the drive voltage can be set to several volts by setting the film thickness.
  • FIG. 72 various modifications of the electron-emitting device 12B used in the light source 10B according to the second embodiment will be described with reference to FIGS. 72 to 77.
  • FIG. 72 various modifications of the electron-emitting device 12B used in the light source 10B according to the second embodiment will be described with reference to FIGS. 72 to 77.
  • the electron-emitting device 12Ba has the same configuration as that of the above-described electron-emitting device 12B.
  • the thickness t of the upper electrode 18 is thicker than 10 m
  • the penetrating part 102 is artificially formed using etching (wet etching, dry etching), lift-off, laser, etc. It has characteristics in that it is.
  • etching wet etching, dry etching
  • lift-off laser, etc. It has characteristics in that it is.
  • As the shape of the penetrating portion 102, the shape of the hole 114, the shape of the notch 128, and the shape of the slit 132 can be adopted as in the electron emitting device 12 ⁇ / b> B described above.
  • the lower surface 108a of the peripheral portion 108 of the penetrating portion 102 in the upper electrode 18 is gradually inclined upward toward the center of the penetrating portion 102.
  • This shape can be easily formed by using, for example, lift-off.
  • the floating electrode 174 may be present in a portion corresponding to the penetrating portion 102 in the upper surface of the emitter portion 22.
  • an electrode having a substantially T-shaped cross section may be formed as the upper electrode 18. ⁇ .
  • the shape of the upper electrode 18, particularly, the shape in which the peripheral portion 108 of the through-hole 102 of the upper electrode 18 is raised may be used.
  • the film material to be the upper electrode 18 may include a material that is gasified during the firing process. Thereby, in the firing step, the material is gasified, and as a result, a large number of through portions 102 are formed in the upper electrode 18 and the peripheral portion 108 of the through portion 102 is lifted.
  • the electron-emitting device 12Be includes a single substrate 176 made of a force having substantially the same configuration as the electron-emitting device 12B described above, for example, ceramics.
  • the lower electrode 20 is formed on the substrate 176
  • the emitter 22 is formed on the substrate 176 so as to cover the lower electrode 20
  • the upper electrode 18 is formed on the emitter 22.
  • a space 178 for forming a thin portion described later is provided at a position corresponding to a portion where each of the emitter portions 22 is formed.
  • the void 178 communicates with the outside through a small-diameter through hole 180 provided on the other end surface of the substrate 176.
  • the portion where the void 178 is formed is thin (hereinafter referred to as the thin portion 182), and the other portions are thick and are fixed to support the thin portion 182. Part 18 4 is now functioning.
  • the substrate 176 is a laminate of the substrate layer 176A as the lowermost layer, the spacer layer 176B as the intermediate layer, and the thin plate layer 176C as the uppermost layer. Part 2 It can be grasped as an integral structure in which a void 178 is formed at a location corresponding to 2.
  • the substrate layer 176A functions not only as a reinforcing substrate but also as a wiring substrate.
  • the substrate 176 may be formed by integrally firing the substrate layer 176A, the spacer layer 176B, and the thin plate layer 176C, or may be formed by adhering these layers 176A-176C.
  • the thin portion 182 is preferably a high heat resistant material.
  • the reason is that when the emitter 22 is structured to directly support the thin portion 18 2 by the fixing portion 184 without using a material having poor heat resistance such as an organic adhesive, at least when the emitter 22 is formed, the thin portion In order to prevent 182 from being altered, the thin-walled portion 182 is preferably a high heat resistant material.
  • the thin-walled portion 182 is preferably an electrically insulating material in order to electrically separate the wiring leading to the upper electrode 18 and the wiring leading to the lower electrode 20 formed on the substrate 176. Good.
  • the material of the thin portion 182 may be a highly heat-resistant metal or a material such as a hollow whose surface is covered with a ceramic material such as glass, but ceramics is most suitable. .
  • Ceramics constituting the thin portion 182 include, for example, stabilized acid-zirconium, acid-aluminum, magnesium oxide, titanium oxide, spinel, mullite, aluminum nitride, silicon nitride, glass, Mixtures of these can be used.
  • acid aluminum and stable acid zirconium power are preferable from the viewpoint of strength and rigidity.
  • Stabilized zirconium oxide is particularly suitable for viewpoints such as relatively high mechanical strength, relatively high toughness, and relatively small chemical reaction with upper electrode 18 and lower electrode 20. It is.
  • the stabilized acid zirconium oxide includes stabilized zirconium oxide and partially stabilized zirconium oxide. Stabilized zirconium oxide has a crystal structure such as a cubic crystal, so no phase transition occurs.
  • zirconium oxide has a phase transition between a monoclinic crystal and a tetragonal crystal at around 1000 ° C, and cracks may occur during such a phase transition.
  • Oxide stabilized zirconium two ⁇ beam is calcium oxide, magnesium oxide, yttrium oxide, scandium oxide, acid I spoon ytterbium, cerium oxide, a stabilizer such as rare earth metal Sani ⁇ , 1 one 30 mole 0 / 0 contains.
  • the stabilizer contains yttrium oxide.
  • yttrium oxide preferably 1. 5-6 mol%, further preferably 2-4 mole 0/0 contains additionally contains aluminum oxide 0.5 1 5 mole 0/0 preferable.
  • the force that can make the crystal phase a cubic + monoclinic mixed phase, a tetragonal + monoclinic mixed phase, a cubic + tetragonal + monoclinic mixed phase, etc.
  • the main crystal phase is a tetragonal or tetragonal + cubic mixed phase.
  • the substrate 176 is formed of ceramics, a relatively large number of crystal grains constitute the substrate 176.
  • the average grain size of the crystal grains is preferably It is better to set the value to 0.05-, more preferably 0.1-.
  • the fixing portion 184 preferably has a ceramic force, but may be the same ceramic as the material of the thin portion 182 or may be different.
  • the ceramic constituting the fixing portion 184 include the stabilized acid zirconium oxide, oxide aluminum, magnesium oxide, titanium oxide, spinel, mullite, and aluminum nitride, similar to the material of the thin portion 182. Silicon nitride, glass, a mixture thereof, or the like can be used.
  • the substrate 176 used in the electron-emitting device 12Be is made of a material mainly composed of acid zirconium, a material mainly composed of acid aluminum, or a material mainly composed of a mixture thereof. Etc. are preferably employed. Of these, those containing zirconium oxide as a main component are more preferable.
  • a clay or the like may be added as a sintering aid, it is necessary to adjust the auxiliary component so as not to include excessively glassy substances such as silicon oxide and boron oxide. This is because these materials that are easily vitrified are advantageous in bonding the substrate 176 and the emitter 22, but promote the reaction between the substrate 176 and the emitter 22, thereby forming a predetermined emitter 22. This is because it is difficult to maintain the characteristics, and as a result, the device characteristics are deteriorated.
  • the silicon oxide or the like in the substrate 176 it is preferable to limit the silicon oxide or the like in the substrate 176 to 3% or less, more preferably 1% or less by weight.
  • the main component is 50% or more by weight.
  • the thickness of the thin portion 182 and the thickness of the emitter portion 22 are preferably the same dimension. This is because if the thickness of the thin portion 182 is extremely thicker than the thickness of the emitter portion 22 (by one digit or more), the thin portion 182 works to prevent the shrinkage of the emitter portion 22 from firing shrinkage. As a result, the stress at the interface between the emitter portion 22 and the substrate 176 increases, and it becomes easy to peel off. On the other hand, if the dimension of the thickness is approximately the same, the substrate 176 (thin wall portion 182) can easily follow the firing shrinkage of the emitter portion 22, which is preferable for an integrated substrate.
  • the thickness of the thin portion 182 is preferably 3 to 100 m, more preferably 3 to 50 m, and even more preferably 5 to 20 m.
  • the thickness of the emitter 22 is preferably 5 to 100 m, more preferably 5 to 50 m, and even more preferably 5 to 30 m.
  • various thick film forming methods such as a screen printing method, a destaining method, a coating method, an electrophoresis method, an aerosol deposition method, and an ion beam method are used.
  • Various thin film forming methods such as sputtering, vacuum deposition, ion plating, chemical vapor deposition (CVD), and plating can be used.
  • CVD chemical vapor deposition
  • a material to be the lower electrode 20 a material to be the emitter 22 and a material to be the upper electrode 18 are sequentially stacked on the substrate 176, and then fired as an integrated structure.
  • a heat treatment may be performed to form an integrated structure with the substrate 176.
  • a heat treatment (firing treatment) for integration may be required!
  • the temperature related to the baking treatment for integrating the substrate 176 with the emitter section 22, the upper electrode 18 and the lower electrode 20 is in the range of 500-1400 ° C, preferably 1000-1400 °. C range is recommended.
  • the firing process may be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the yarn formation of the emitter 22 is not unstable at high temperatures.
  • a method may be employed in which the emitter portion 22 is covered with an appropriate member, and firing is performed such that the surface of the emitter portion 22 is not directly exposed to the firing atmosphere. In this case, it is preferable to use the same material as the substrate 176 as the covering member.
  • the emitter portion 22 contracts during firing, but the stress generated during the contraction is released through deformation of the void 178 or the like. Therefore, the emitter 22 can be sufficiently densified.
  • the withstand voltage is improved, and the polarization inversion and polarization change in the emitter 22 are efficiently performed, thereby improving the characteristics as the electron-emitting device 12 Be. become.
  • the light emitting unit 14B is divided into two groups (first and second groups G1), similarly to the light source 10Ac according to the third modification shown in FIG. And G2), when the electron-emitting device 12B included in the first group G1 emits light, the power of the electron-emitting device 12B included in the first group G1 in the electron-emitting device 12B included in the second group G2 When the electron-emitting devices 12B included in the second group G2 emit light, the electron-emitting devices 12B included in the second group G2 Even if you collect power.
  • the light source 10B according to the second embodiment may have two or more surface light source units Z1-Z6, as in the light source lOAe according to the fifth modification example of FIG. .
  • the example of FIG. 29 shows a case where six surface light source units Z1 to Z6 are provided.
  • Each surface light source unit Z1-Z6 is configured by two-dimensionally arranging a plurality of electron-emitting devices 12B, and a drive circuit 16B is independently connected thereto.
  • stepwise light control digital light control
  • the emission distribution of each surface light source unit Z1-Z6 can be controlled independently. can do. That means In addition to digital dimming, analog dimming can be realized and fine dimming can be performed.
  • the first and sixth surface light source units Z1 and Z6 are horizontally long like the light source lOAf according to the sixth modification shown in FIG. Therefore, it is assumed that the rectangular shape has a long long side, the second and fifth surface light source sections are vertically long, and the long side is a rectangular shape shorter than the first and sixth surface light source sections Z1 and Z6.
  • the third and fourth surface light source units Z3 and Z4 may be horizontally long, and the long sides may be shorter than the first and sixth surface light source units Z1 and Z6.
  • each surface light source unit Z1-Z6 includes a plurality of electron-emitting devices included in each surface light source unit Z1-Z6, as in the light source lOAg according to the seventh modification shown in FIG. 12B is divided into two groups (first and second groups G1 and G2), and each surface light source unit Z1-Z6 has the first group when the electron-emitting device 12B included in the first group emits light.
  • the power of the electron-emitting device 12B included in G1 is recovered by the electron-emitting device 12B included in the second group G2, and when the electron-emitting device 12B included in the second group G2 emits light, The power of the electron-emitting device 12B included in the group G2 may be collected by the electron-emitting device 12B included in the first group G1.
  • the light source 10B according to the second embodiment as in the light source lOAh according to the eighth modification shown in FIG. And the second group G1 and G2), and when the light emitting elements 12B of the surface light source units Z1 to Z3 relating to the first group G1 emit light, the power of these electron emitting elements 12B is changed to the second group G2 Are collected in the electron emitters 12B of the surface light source parts Z4—Z6, and the power of the electron emitters 12B in the surface light source parts Z4—Z6 of the second group G2 is emitted at the time of light emission.
  • the surface light source unit Z1-Z3 related to the first group G1 may be collected in the electron-emitting device 12B.
  • the configuration shown in the light source lOAi- lOAm according to the ninth to the thirteenth modification examples shown in Figs. 33 to 37 may be adopted. .
  • the light source 10A according to the first embodiment (including various modifications) and the light source 10B according to the second embodiment (including various modifications) can have the following effects. . [0337] (1) Because it can achieve high brightness and low power consumption, it is optimal for projector light sources that require 2000 lumens as a brightness specification.
  • the allowable current decreases and the brightness decreases.
  • a surface light source configured by two-dimensionally arranging electron-emitting devices can be controlled to be turned on / off in units of elements, it is suitable for applications in which a part of the light emitting area is turned on / off. is there. In addition, since instant lighting is possible, no warm-up time is required. Furthermore, when applied as a backlight for liquid crystal displays, it is also possible to improve moving image quality (improving moving image blurring) by high-speed lighting.
  • the light source according to the present invention is not limited to the above-described embodiment, but can of course have various configurations without departing from the gist of the present invention.

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Abstract

Light sources (10A, 10B) are provided with a light emitting part (14) whereupon a plurality of electron emitting elements (12A, 12B) are two-dimensionally arranged, and driving circuits (16A, 16B) for applying a driving voltage (Va) to each of the electron emitting elements (12A, 12B) of the light emitting part (14). The driving circuits (16A, 16B) apply the driving voltage (Va) to an upper electrode (18) and a lower electrode (20) of each of the electron emitting elements (12A, 12B), based on a control signal (Sc) from an external (a switch for turning on/off light, or the like) for indicating turning on/off, and each of the electron emitting elements (12A, 12B) is drive-controlled. Each of the electron emitting elements (12A, 12B) is provided with a board-shaped emitter part (22), the upper electrode (18) formed on a front plane of the emitter part (22), and a lower electrode (20) formed on a rear plane of the emitter part (22).

Description

明 細 書  Specification
光源  Light source
技術分野  Technical field
[0001] 本発明は、ェミッタ部に形成された上部電極と下部電極を有する電子放出素子を 用いた光源 (面光源を含む）に関する。  [0001] The present invention relates to a light source (including a surface light source) using an electron-emitting device having an upper electrode and a lower electrode formed in an emitter section.
背景技術  Background art
[0002] 近時、電子放出素子は、駆動電極及びコモン電極を有し、フィールドェミッションデ イスプレイ（FED)やバックライトのような種々のアプリケーションに適用されている。 F EDに適用する場合、複数の電子放出素子を二次元的に配列し、これら電子放出素 子に対する複数の蛍光体を、所定の間隔をもってそれぞれ配置するようにしている。  Recently, an electron-emitting device has a drive electrode and a common electrode, and is applied to various applications such as field emission display (FED) and backlight. When applied to FED, a plurality of electron-emitting devices are two-dimensionally arranged, and a plurality of phosphors corresponding to these electron-emitting devices are respectively arranged with a predetermined interval.
[0003] この電子放出素子の従来例としては、例えば特許文献 1一 5がある力 いずれもエミ ッタ部に誘電体を用いて ヽな ヽため、対向電極間にフォーミンダカ卩ェもしくは微細加 ェが必要となったり、電子放出のために高電圧を印加しなければならず、また、パネ ル製作工程が複雑で製造コストが高くなるという問題がある。  [0003] As a conventional example of this electron-emitting device, for example, any force having Patent Documents 1 to 15 uses a dielectric for the emitter part. This requires a high voltage for electron emission, and the panel manufacturing process is complicated and the manufacturing cost is high.
[0004] そこで、ェミッタ部を誘電体で構成することが考えられている力 誘電体からの電子 放出として、以下の非特許文献 1、 2にて諸説が述べられている。  [0004] Therefore, various theories are described in Non-Patent Documents 1 and 2 below regarding electron emission from a ferrodielectric which is considered to be composed of a dielectric.
特許文献 1 :特開平 1 - 311533号公報  Patent Document 1: JP-A-1-311533
特許文献 2 :特開平 7 - 147131号公報  Patent Document 2: JP-A-7-147131
特許文献 3：特開 2000— 285801号公報  Patent Document 3: Japanese Patent Laid-Open No. 2000-285801
特許文献 4：特公昭 46— 20944号公報  Patent Document 4: Japanese Patent Publication No. 46-20944
特許文献 5：特公昭 44— 26125号公報  Patent Document 5: Japanese Patent Publication No. 44-26125
非特許文献 1：安岡、石井「強誘電体陰極を用いたパルス電子源」応用物理第 68卷 第 5号、 p546— 550 (1999)  Non-Patent Document 1: Yasuoka, Ishii “Pulse Electron Source Using a Ferroelectric Cathode” Applied Physics No. 68 卷 No. 5, p546-550 (1999)
非特干文献 2 :V.F.Puchkarev, G.A.Mesyats, On the mechanism of emission from theferroelectric ceramic cathode, J.Appl.Phys., vol. 78, No. 9, 1 November, 1995, p. 5633-5637  Non-Patent Literature 2: V.F.Puchkarev, G.A.Mesyats, On the mechanism of emission from theferroelectric ceramic cathode, J.Appl.Phys., Vol. 78, No. 9, 1 November, 1995, p. 5633-5637
発明の開示 発明が解決しょうとする課題 Disclosure of the invention Problems to be solved by the invention
[0005] 上述した従来の電子放出素子にお!、ては、誘電体の表面、誘電体と上部電極との 界面、誘電体内部の欠陥準位に拘束された電子を誘電体の分極反転によって放出 するようにしている。つまり、誘電体にて分極反転さえ起きれば、印加電圧パルスの 電圧レベルに依存せず、放出電子量はほぼ一定となる。  [0005] In the above-mentioned conventional electron-emitting device, the electrons constrained by the surface of the dielectric, the interface between the dielectric and the upper electrode, and the defect level inside the dielectric are converted by polarization inversion of the dielectric. It is trying to release. In other words, as long as polarization reversal occurs in the dielectric, the amount of emitted electrons is almost constant regardless of the voltage level of the applied voltage pulse.
[0006] し力しながら、電子放出が安定せず、電子放出回数はたかだか数万回程度までで あり、例えば光源として用いた場合の実用性に乏し 、と 、う問題がある。  However, the electron emission is not stable and the number of electron emission is up to about several tens of thousands of times. For example, there is a problem that the practicality when used as a light source is poor.
[0007] 本発明はこのような課題を考慮してなされたものであり、誘電体にて構成されたエミ ッタ部を有する電子放出素子において、電子の過剰放出を抑制して、電子放出に伴 う電極等での損傷等を防止することができ、長寿命化及び信頼性の向上を図ることが できる光源を提供することを目的とする。  [0007] The present invention has been made in consideration of such problems, and in an electron-emitting device having an emitter portion made of a dielectric material, excessive emission of electrons is suppressed, and electron emission is suppressed. An object of the present invention is to provide a light source capable of preventing damage and the like in the accompanying electrodes and the like and capable of extending the life and improving the reliability.
[0008] また、本発明の他の目的は、高い電界集中を容易に発生させることができ、しかも、 電子放出箇所を多くすることができ、電子放出について高出力、高効率を図ることが でき、低電圧駆動も可能な光源を提供することにある。 [0008] In addition, another object of the present invention is to easily generate a high electric field concentration, to increase the number of electron emission locations, and to achieve high output and high efficiency for electron emission. Another object is to provide a light source that can be driven at a low voltage.
課題を解決するための手段  Means for solving the problem
[0009] 第 1の発明に係る光源は、電子が物質に衝突することによって光を発生する光源に おいて、前記電子の発生源は、電子放出素子であり、前記電子放出素子は、誘電体 にて構成されたェミッタ部と、前記ェミッタ部に形成された第 1の電極及び第 2の電極 とを有し、前記第 1の電極と前記第 2の電極間に駆動電圧が印加されることによって、 少なくとも前記ェミッタ部の一部が分極反転あるいは分極変化されることで電子放出 を行うことを特徴とする。前記ェミッタ部は、圧電材料、反強誘電体材料又は電歪材 料で構成することができる。 [0009] A light source according to a first aspect of the present invention is a light source that generates light when electrons collide with a substance. The electron generation source is an electron-emitting device, and the electron-emitting device is a dielectric. And a drive voltage is applied between the first electrode and the second electrode, and the first electrode and the second electrode formed in the emitter portion. Thus, at least a part of the emitter part is subjected to polarization inversion or polarization change to emit electrons. The emitter section can be composed of a piezoelectric material, an antiferroelectric material, or an electrostrictive material.
[0010] ここで、第 1の発明に係る電子放出素子の作用について説明する。先ず、第 1の電 極と第 2の電極間に駆動電圧が印加されることによって、少なくともェミッタ部の一部 が分極反転あるいは分極変化され、第 2の電極よりも電位が低い前記第 1の電極の 近傍カゝら電子が放出されることになる。即ち、この分極反転あるいは分極変化によつ て、第 1の電極とその近傍の双極子の正極側とで局所的な集中電界が発生すること により、前記第 1の電極から 1次電子が引き出され、前記第 1の電極から引き出された 1次電子が前記ェミッタ部に衝突して、該ェミッタ部から 2次電子が放出される。 Here, the operation of the electron-emitting device according to the first invention will be described. First, when a driving voltage is applied between the first electrode and the second electrode, at least a part of the emitter section undergoes polarization inversion or polarization change, and the potential is lower than that of the second electrode. Electrons are emitted from the vicinity of the electrode. That is, due to this polarization reversal or polarization change, a local concentrated electric field is generated between the first electrode and the positive pole side of the nearby dipole, so that primary electrons are extracted from the first electrode. Pulled out of the first electrode Primary electrons collide with the emitter and secondary electrons are emitted from the emitter.
[0011] 前記第 1の電極、前記ェミッタ部及び真空雰囲気の 3重点を有する場合には、前記 第 1の電極のうち、 3重点近傍の部分から 1次電子が引き出され、前記引き出された 1 次電子が前記ェミッタ部に衝突して、該ェミッタ部から 2次電子が放出される。ここで 述べる 2次電子は、 1次電子のクーロン衝突でエネルギーを得て、ェミッタ部の外へ 飛び出した固体内電子とオージ 電子と、 1次電子がェミッタ部の表面近くで散乱し たもの (反射電子）の全てを含む。なお、前記第 1の電極の厚みが極薄（一 lOnm)で ある場合には、該第 1の電極とェミッタ部との界面力も電子が放出されることになる。 [0011] When the first electrode, the emitter portion, and the vacuum atmosphere have a triple point, primary electrons are extracted from a portion of the first electrode in the vicinity of the triple point, and the extracted 1 Secondary electrons collide with the emitter and secondary electrons are emitted from the emitter. The secondary electrons described here obtain energy from the Coulomb collision of the primary electrons, and electrons inside the solid and auger electrons that have jumped out of the emitter, and primary electrons scattered near the surface of the emitter ( All of the reflected electrons). When the thickness of the first electrode is extremely thin (one lOnm), electrons are also emitted by the interface force between the first electrode and the emitter portion.
[0012] このような原理によって電子が放出されることから、本発明に係る光源は、電子放出 が安定して行われ、電子放出の回数も 20億回以上を実現でき、光源として実用性に 富む。しカゝも、放出電子量は、第 1の電極と第 2の電極間に印加される駆動電圧のレ ベルにほぼ比例して増加することから、放出電子量を容易に制御できるという利点も ある。 [0012] Because electrons are emitted according to such a principle, the light source according to the present invention can stably emit electrons, and can achieve more than 2 billion times of electron emission, making it practical as a light source. Rich. However, the amount of emitted electrons increases almost in proportion to the level of the drive voltage applied between the first electrode and the second electrode, so that the amount of emitted electrons can be easily controlled. is there.
[0013] なお、第 2の電極に引かれた電子は、主に第 2の電極の近傍に存在する気体又は 第 2の電極を構成する原子等を正イオンと電子に電離する。前記第 2の電極の近傍 に存在する前記第 2の電極を構成する原子は、該第 2の電極の一部が蒸散した結果 生じた原子であり、該原子は前記第 2の電極の近傍に浮遊している。そして、前記電 離によって発生した電子が更に気体や前記原子等を電離するため、指数関数的に 電子が増え、これが進行して電子と正イオンが中性的に存在すると局所プラズマとな る。  [0013] Note that the electrons drawn to the second electrode ionize mainly the gas existing in the vicinity of the second electrode or the atoms constituting the second electrode into positive ions and electrons. The atoms constituting the second electrode existing in the vicinity of the second electrode are atoms generated as a result of evaporation of a part of the second electrode, and the atoms are in the vicinity of the second electrode. It is floating. Then, the electrons generated by the ionization further ionize the gas, the atoms, etc., so that the number of electrons increases exponentially, and when this proceeds and the electrons and positive ions are neutral, a local plasma is formed.
[0014] そして、前記電離によって発生した正イオン力 例えば第 1の電極に衝突することに よって、第 1の電極が損傷することも考えられる。  [0014] It is also conceivable that the positive electrode force generated by the ionization, for example, the first electrode is damaged by colliding with the first electrode.
[0015] そこで、ェミッタ部の第 1の面に第 1の電極を形成し、ェミッタ部の第 2の面に第 2の 電極を形成するようにすれば、第 1の電極カゝら放出された電子力 局所アノードとして 存在するェミッタ部の双極子の +極に引かれ、第 1の電極の近傍におけるェミッタ部 の第 1の面において、負極性への帯電が進行することになる。その結果、電子の加速 因子（局所的な電位差）が緩和され、 2次電子放出に至るポテンシャルが存在しなく なり、前記ェミッタ部の第 1の面が負極性に帯電していくことになる。 [0016] そのため、双極子における局所的なアノードの正極性が弱められ、局所的なァノー ドと局所的な力ソード間の電界の強さが小さくなり、電子放出が停止することになる。 [0015] Therefore, if the first electrode is formed on the first surface of the emitter section and the second electrode is formed on the second surface of the emitter section, the first electrode cover emits light. Electron force is attracted by the + pole of the dipole of the emitter that exists as a local anode, and charging to the negative polarity proceeds on the first surface of the emitter in the vicinity of the first electrode. As a result, the electron acceleration factor (local potential difference) is relaxed, the potential leading to secondary electron emission does not exist, and the first surface of the emitter portion is charged negatively. [0016] Therefore, the positive polarity of the local anode in the dipole is weakened, the strength of the electric field between the local anode and the local force sword is reduced, and electron emission is stopped.
[0017] このように、本発明においては、電子の過剰放出を抑制して、電子放出に伴う第 1 の電極での損傷等を防止することができ、電子放出素子を用いた光源の長寿命化及 び信頼性の向上を図ることができる。  [0017] Thus, in the present invention, excessive emission of electrons can be suppressed, damage to the first electrode accompanying electron emission, etc. can be prevented, and a long life of a light source using an electron-emitting device can be prevented. And improvement of reliability.
[0018] 次に、第 2の発明に係る光源は、電子が衝突することによって光を発生する光源に おいて、前記電子の発生源が電子放出素子であり、前記電子放出素子は、誘電体 で構成されたェミッタ部と、電子放出のための駆動電圧が印加される第 1の電極及び 第 2の電極とを有し、前記第 1の電極は、前記ェミッタ部の第 1の面に形成され、前記 第 2の電極は、前記ェミッタ部の第 2の面に形成され、少なくとも前記第 1の電極は、 前記ェミッタ部が露出される複数の貫通部を有し、前記第 1の電極のうち、前記貫通 部の周部における前記ェミッタ部と対向する面が、前記ェミッタ部力 離間しているこ とを特徴とする (第 2の発明)。この場合、前記電子放出素子は、第 1段階に、前記第 1の電極力 前記ェミッタ部に向けて電子放出が行われて、前記ェミッタ部が帯電さ れ、第 2段階に、前記ェミッタ部力 電子放出が行われるようにしてもよい。  [0018] Next, a light source according to a second aspect of the present invention is a light source that generates light by collision of electrons, wherein the electron generation source is an electron-emitting device, and the electron-emitting device is a dielectric material. A first electrode and a second electrode to which a driving voltage for electron emission is applied, and the first electrode is formed on the first surface of the emitter unit The second electrode is formed on a second surface of the emitter portion, and at least the first electrode has a plurality of through portions from which the emitter portion is exposed. Of these, the surface of the peripheral portion of the penetrating portion that faces the emitter portion is separated from the force of the emitter portion (second invention). In this case, in the first stage, the electron-emitting device emits electrons toward the first electrode force toward the emitter section, the emitter section is charged, and the emitter section force in the second stage. Electron emission may be performed.
[0019] ここで、第 2の発明に係る電子放出素子の作用について説明する。先ず、第 1の電 極と第 2の電極との間に駆動電圧が印加される。この駆動電圧は、例えば、パルス電 圧あるいは交流電圧のように、時間の経過に伴って、基準電圧 (例えば OV)よりも高 Vヽ又は低 ヽ電圧レベルから基準電圧よりも低 ヽ又は高 ヽ電圧レベルに急激に変化 する電圧として定義される。  Here, the operation of the electron-emitting device according to the second invention will be described. First, a driving voltage is applied between the first electrode and the second electrode. This drive voltage is, for example, a pulse voltage or an AC voltage, which is higher or lower than a reference voltage (e.g. OV) over time from a voltage level that is lower or higher than the reference voltage. Defined as a voltage that changes rapidly to a voltage level.
[0020] また、ェミッタ部の第 1の面と第 1の電極と該電子放出素子の周囲の媒質 (例えば、 真空）との接触箇所においてトリプルジャンクションが形成されている。ここで、トリプ ルジャンクションとは、第 1の電極とェミッタ部と真空との接触により形成される電界集 中部として定義される。なお、前記トリプルジャンクションには、第 1の電極とェミッタ部 と真空が 1つのポイントとして存在する 3重点も含まれる。本発明では、トリプルジヤン クシヨンは、複数の貫通部の周部や第 1の電極の周縁部に形成されることになる。従 つて、第 1の電極と第 2の電極との間に上述のような駆動電圧が印加されると、上記し たトリプルジャンクションにおいて電界集中が発生する。 [0021] そして、第 1段階にお!、て、基準電圧よりも高!、又は低!、電圧が第 1の電極と第 2の 電極間に印加され、上記したトリプルジャンクションにおいて例えば一方向への電界 集中が発生し、第 1の電極力 ェミッタ部に向けて電子放出が行われ、例えばェミツ タ部のうち、第 1の電極の貫通部に対応した部分や第 1の電極の周縁部近傍の部分 に電子が蓄積される。すなわち、ェミッタ部が帯電することになる。このとき、第 1の電 極が電子供給源として機能する。 [0020] Further, a triple junction is formed at a contact point between the first surface of the emitter section, the first electrode, and a medium (for example, vacuum) around the electron-emitting device. Here, the triple junction is defined as the electric field concentration portion formed by the contact between the first electrode, the emitter portion, and the vacuum. The triple junction includes a triple point where the first electrode, the emitter part, and the vacuum exist as one point. In the present invention, the triple junction is formed in the peripheral portion of the plurality of through portions and the peripheral portion of the first electrode. Therefore, when the drive voltage as described above is applied between the first electrode and the second electrode, electric field concentration occurs in the triple junction described above. [0021] Then, in the first stage, the voltage is higher or lower than the reference voltage, and a voltage is applied between the first electrode and the second electrode, and in the triple junction described above, for example, in one direction. The electric field concentration occurs, and electrons are emitted toward the first electrode force emitter part.For example, in the emitter part, the part corresponding to the penetrating part of the first electrode or the vicinity of the peripheral part of the first electrode Electrons are accumulated in the part. That is, the emitter portion is charged. At this time, the first electrode functions as an electron supply source.
[0022] 次の第 2段階にぉ 、て、駆動電圧の電圧レベルが急減に変化して、基準電圧よりも 低い又は高い電圧が第 1の電極と第 2の電極間に印加されると、今度は、第 1の電極 の貫通部に対応した部分や第 1の電極の周縁部近傍に帯電した電子は、逆方向へ 分極反転したェミッタ部の双極子 (ェミッタ部の表面に負極性が現れる）により、ェミツ タ部から追い出され、ェミッタ部のうち、前記電子が蓄積されていた部分から、貫通部 を通じて電子が放出される。もちろん、第 1の電極の外周部近傍力 も電子が放出さ れる。このとき、前記第 1段階における前記ェミッタ部の帯電量に応じた電子が、前記 第 2段階に前記ェミッタ部から放出される。また、前記第 1段階における前記ェミッタ 部の帯電量が、前記第 2段階での電子放出が行われるまで維持される。  [0022] During the next second stage, when the voltage level of the drive voltage changes suddenly and a voltage lower or higher than the reference voltage is applied between the first electrode and the second electrode, This time, the electrons charged in the part corresponding to the penetration part of the first electrode and the vicinity of the peripheral part of the first electrode are dipoles of the emitter part whose polarity is reversed in the reverse direction (negative polarity appears on the surface of the emitter part) ), The electrons are expelled from the emitter section, and electrons are emitted from the portion of the emitter section where the electrons are accumulated through the penetrating section. Of course, electrons are also emitted by the force near the outer periphery of the first electrode. At this time, electrons corresponding to the charge amount of the emitter in the first stage are emitted from the emitter in the second stage. Further, the charge amount of the emitter section in the first stage is maintained until the electron emission in the second stage is performed.
[0023] そして、この電子放出素子においては、先ず、第 1の電極に複数の貫通部を形成し たことから、各貫通部並びに第 1の電極の外周部近傍から均等に電子が放出され、 全体の電子放出特性のばらつきが低減し、電子放出の制御が容易になると共に、電 子放出効率が高くなる。  [0023] In this electron-emitting device, first, since the plurality of through portions are formed in the first electrode, electrons are evenly emitted from each through portion and the vicinity of the outer periphery of the first electrode, Variations in the overall electron emission characteristics are reduced, control of electron emission is facilitated, and electron emission efficiency is increased.
[0024] また、この第 2の発明は、前記第 1の電極のうち、前記貫通部の周部における前記 ェミッタ部と対向する面と前記ェミッタ部との間にギャップが形成された形となることか ら、駆動電圧を印力 tlした際に、該ギャップの部分において電界集中が発生し易くなる 。これは、電子放出の高効率ィ匕につながり、駆動電圧の低電圧化 (低い電圧レベル での電子放出）を実現させることができる。  [0024] In the second invention, a gap is formed between the surface of the first electrode facing the emitter portion in the peripheral portion of the through portion and the emitter portion. Therefore, when the driving voltage is applied, tl, electric field concentration is likely to occur in the gap portion. This leads to a high efficiency of electron emission and can realize a low driving voltage (electron emission at a low voltage level).
[0025] 上述したように、第 2の発明は、前記第 1の電極のうち、前記貫通部の周部における 前記ェミッタ部と対向する面と前記ェミッタ部との間にギャップが形成されて、第 1の 電極における貫通部の周部が庇状 (フランジ状）となることから、ギャップの部分での 電界集中が大きくなることとも相俟って、前記庇状の部分 (貫通部の周部)から電子 が放出され易くなる。これは、電子放出の高出力、高効率化につながり、駆動電圧の 低電圧化を実現させることができる。また、第 1の電極における貫通部の周部がゲー ト電極 (制御電極、フォーカス電子レンズ等）として機能するので、放出電子の直進性 を向上させることができる。これは、例えば電子放出素子を多数並べて例えばデイス プレイの電子源として構成した場合に、クロストークを低減する上で有利となる。 [0025] As described above, in the second invention, a gap is formed between the surface of the first electrode facing the emitter portion in the periphery of the penetrating portion and the emitter portion. Since the peripheral portion of the penetrating portion in the first electrode has a hook shape (flange shape), the electric field concentration in the gap portion is increased, and thus the hook-shaped portion (the peripheral portion of the penetrating portion is ) From electron Is easily released. This leads to a high output and high efficiency of electron emission, and a low drive voltage can be realized. In addition, since the peripheral portion of the penetrating portion in the first electrode functions as a gate electrode (control electrode, focus electron lens, etc.), the straightness of the emitted electrons can be improved. This is advantageous in reducing crosstalk, for example, when a large number of electron-emitting devices are arranged to constitute, for example, a display electron source.
[0026] このように、第 2の発明においては、高い電界集中を容易に発生させることができ、 しかも、電子放出箇所を多くすることができ、電子放出について高出力、高効率を図 ることができ、低電圧駆動 (低消費電力)も可能となる。  [0026] Thus, in the second invention, high electric field concentration can be easily generated, moreover, the number of electron emission locations can be increased, and high output and high efficiency can be achieved for electron emission. And low voltage drive (low power consumption) is also possible.
[0027] そして、第 1及び第 2の発明に係る光源は、前記第 1の電極と前記第 2の電極間に 前記ェミッタ部の少なくとも一部を分極反転あるいは分極変化させるための交流パル スを印加する手段を有し、前記ェミッタ部から電子を間欠的に放出するようにしてもよ い。この場合、 1回の電子放出による発光が消光する前に次の電子放出を行うことで 、連続発光させるようにしてもよい。  [0027] The light source according to the first and second inventions includes an AC pulse for reversing or changing polarization of at least a part of the emitter section between the first electrode and the second electrode. There may be means for applying, and electrons may be intermittently emitted from the emitter section. In this case, continuous light emission may be performed by performing the next electron emission before the light emission by one electron emission is quenched.
[0028] また、第 1及び第 2の発明に係る光源は、ェミッタ部の上方のうち、前記第 1の電極 に対向した位置に第 3の電極を配置し、該第 3の電極に蛍光体を塗布して構成する ようにしてもよい。この場合、放出された電子のうち、一部の電子は第 3の電極に導か れて蛍光体を励起し、外部に蛍光体発光として具現される。  [0028] Further, the light source according to the first and second inventions includes a third electrode disposed above the emitter section at a position facing the first electrode, and the phosphor is disposed on the third electrode. You may make it comprise and apply | coat. In this case, some of the emitted electrons are guided to the third electrode to excite the phosphor, and are realized as phosphor emission outside.
[0029] また、第 1及び第 2の発明に係る光源は、電子放出素子の周辺に蛍光体を配置し、 電子放出素子と蛍光体間の雰囲気中に、例えば水銀粒子等を封入して構成するよう にしてもよい。この場合、放出された電子のうち、一部の電子は水銀粒子に衝突し、 水銀粒子が励起状態になって紫外線を発する。この紫外線が、周辺の蛍光体に当 たること〖こよって、蛍光体が励起して外部に蛍光体発光として具現される。  In addition, the light source according to the first and second inventions is configured by arranging a phosphor around the electron-emitting device and enclosing, for example, mercury particles in an atmosphere between the electron-emitting device and the phosphor. You may do it. In this case, some of the emitted electrons collide with the mercury particles, and the mercury particles are excited to emit ultraviolet rays. When this ultraviolet ray hits the surrounding phosphor, the phosphor is excited and embodied as phosphor emission to the outside.
[0030] そして、前記構成において、複数の電子放出素子を二次元的に配列するようにし てもよい。これによつて、電子放出素子を用い、かつ、長寿命化及び信頼性の向上を 図ることができる面光源が実現されること〖こなる。  [0030] In the above configuration, a plurality of electron-emitting devices may be arranged two-dimensionally. As a result, a surface light source using an electron-emitting device and capable of extending the life and improving the reliability is realized.
[0031] ここで、面光源の利点をディスプレイとの差異で説明すると、面光源は、ディスプレ ィと異なり、常に全面発光でよいため、例えば行走査等の複雑な駆動を行う必要がな ぐ一括のスタティック駆動でよい。また、電子放出による発光スポット径の制御が不 要になることから、電子放出素子と蛍光体間に例えばフォーカスレンズとしての機能 を果たす制御電極等を設置する必要がない。これは、機械的構成並びに回路構成 の簡略ィ匕につながる。 [0031] Here, the advantages of the surface light source will be explained by the difference from the display. Unlike the display, the surface light source may always emit the entire surface, so that it is not necessary to perform complicated driving such as row scanning, for example. Static drive is sufficient. In addition, control of the emission spot diameter by electron emission is inadequate. Therefore, it is not necessary to install, for example, a control electrode that functions as a focus lens between the electron-emitting device and the phosphor. This leads to simplification of the mechanical configuration as well as the circuit configuration.
[0032] ディスプレイは、画像信号に応じて高速に変化するデータ信号を扱う必要がある。  [0032] The display needs to handle a data signal that changes at high speed according to an image signal.
従って、駆動電圧は、階調に応じて変調された複雑な波形となる。一方、面光源は、 画像信号に応じて高速に変化するデータ信号を扱う必要がないため、駆動電圧とし て単純な波形 (パルス周期やパルス幅がそれぞれ一定とされた波形)を用いることが できる。その結果、面光源に電力回収回路を接続する場合に、該電力回収回路の回 路定数、回路切り換えタイミング等を高精度に設定できるだけでなぐ駆動電圧のほ ぼ 100%を電力回収させることも可能となる。  Therefore, the drive voltage has a complex waveform modulated according to the gradation. On the other hand, a surface light source does not need to handle a data signal that changes at a high speed in accordance with an image signal, so a simple waveform (a waveform with a constant pulse period and pulse width) can be used as a drive voltage. . As a result, when a power recovery circuit is connected to the surface light source, it is possible to recover almost 100% of the drive voltage as long as the circuit constant and circuit switching timing of the power recovery circuit can be set with high accuracy. It becomes.
[0033] そして、前記複数の電子放出素子を 2つのグループに分け、一方のグループに含 まれる電子放出素子の発光時に、他方のグループに含まれる電子放出素子が、前 記一方のグループに含まれる電子放出素子の電力を回収し、前記他方のグループ に含まれる電子放出素子の発光時に、一方のグループに含まれる電子放出素子が 、前記他方のグループに含まれる電子放出素子の電力を回収するようにしてもよい。  [0033] The plurality of electron-emitting devices are divided into two groups, and when the electron-emitting devices included in one group emit light, the electron-emitting devices included in the other group are included in the one group. The electron emission element included in the other group collects the power of the electron emission element included in the other group when the electron emission element included in the other group emits light. You may do it.
[0034] つまり、発光動作を行っているグループ以外のグループに含まれる電子放出素子 1S 電力回収のための、いわゆるバッファコンデンサとして兼用することから、別途バ ッファコンデンサを設置する必要がなぐ実装面積の縮小化、消費電力の低減を有 効に図ることができる。  [0034] In other words, the electron-emitting device 1S included in a group other than the group performing the light-emitting operation 1S Mounting area that does not require a separate buffer capacitor because it also serves as a so-called buffer capacitor for power recovery It is possible to effectively reduce the power consumption and power consumption.
[0035] また、前記構成にお!、て、前記駆動電圧を制御信号に基づ!、て変調して、前記電 子放出素子の電子放出量を制御することによって調光を行うようにしてもよい。  [0035] Further, according to the configuration, the drive voltage is modulated based on a control signal, and the light emission is controlled by controlling the electron emission amount of the electron-emitting device. Also good.
[0036] また、第 1及び第 2の発明に係る光源は、 2以上の面光源部を有するようにしてもよ い。この場合、前記各面光源部は、前記電子放出素子を複数有し、該複数の電子放 出素子が二次元的に配列されて 、てもよ 、。  [0036] The light source according to the first and second inventions may include two or more surface light source units. In this case, each surface light source unit may include a plurality of the electron-emitting devices, and the plurality of electron-emitting devices may be two-dimensionally arranged.
[0037] これによつて、面光源部単位に発光 Z消光を制御することができ、段階的な調光（ デジタル的な調光)を行うことができる。特に、各面光源部について、それぞれ電子 放出素子に印加される駆動電圧を、対応する制御信号に基づいて変調して、前記電 子放出素子の電子放出量を制御することによって各面光源部の調光を行う手段を設 けることで、各面光源部の発光分布を制御することができる。つまり、デジタル的な調 光に加えて、アナログ的な調光を実現でき、きめ細かな調光を行うことができる。 [0037] With this, it is possible to control light emission Z quenching in units of surface light source units, and to perform stepwise light control (digital light control). In particular, for each surface light source unit, the driving voltage applied to each electron emission element is modulated based on the corresponding control signal, and the amount of electron emission of the electron emission element is controlled to control each surface light source unit. Provide a means to perform dimming Therefore, the light emission distribution of each surface light source unit can be controlled. In other words, in addition to digital dimming, analog dimming can be realized, and fine dimming can be performed.
[0038] また、前記構成において、前記各面光源部に含まれる前記複数の電子放出素子を それぞれ 2つのグループに分け、一方のグループに含まれる電子放出素子の発光 時に、他方のグループに含まれる電子放出素子力 前記一方のグループに含まれる 電子放出素子の電力を回収し、前記他方のグループに含まれる電子放出素子の発 光時に、一方のグループに含まれる電子放出素子が、前記他方のグループに含ま れる電子放出素子の電力を回収するようにしてもょ 、。  [0038] In the above configuration, the plurality of electron-emitting devices included in each surface light source unit are divided into two groups, respectively, and are included in the other group when the electron-emitting devices included in one group emit light. Electron-emitting device force The power of the electron-emitting devices included in the one group is recovered, and when the electron-emitting devices included in the other group emit light, the electron-emitting devices included in one group But let's collect the power of the electron-emitting devices contained in the.
[0039] また、前記 2以上の面光源部を 2つのグループに分け、一方のグループに含まれる 電子放出素子の発光時に、他方のグループに含まれる電子放出素子が、前記一方 のグループに含まれる電子放出素子の電力を回収し、前記他方のグループに含ま れる電子放出素子の発光時に、一方のグループに含まれる電子放出素子が、前記 他方のグループに含まれる電子放出素子の電力を回収するようにしてもょ 、。  [0039] Further, the two or more surface light source sections are divided into two groups, and when the electron-emitting devices included in one group emit light, the electron-emitting devices included in the other group are included in the one group. The power of the electron-emitting devices is recovered, and when the light-emitting devices included in the other group emit light, the electron-emitting devices included in one group recover the power of the electron-emitting devices included in the other group. Anyway.
[0040] 以上説明したように、本発明に係る光源によれば、誘電体にて構成されたェミッタ 部を有する電子放出素子において、電子の過剰放出を抑制して、電子放出に伴う電 極等での損傷等を防止することができ、長寿命化及び信頼性の向上を図ることがで きる。  [0040] As described above, according to the light source of the present invention, in an electron-emitting device having an emitter portion made of a dielectric material, an excessive emission of electrons is suppressed, and an electrode associated with electron emission or the like. Damage, etc. can be prevented, and the service life can be extended and the reliability can be improved.
[0041] また、高い電界集中を容易に発生させることができ、し力も、電子放出箇所を多くす ることができ、電子放出について高出力、高効率を図ることができ、低電圧駆動も可 能となる。  [0041] In addition, high electric field concentration can be easily generated, the force can be increased, the number of electron emission locations can be increased, high output and high efficiency can be achieved for electron emission, and low voltage driving is also possible. It becomes ability.
図面の簡単な説明  Brief Description of Drawings
[0042] [図 1]図 1は、第 1の実施の形態に係る光源を示す構成図である。 FIG. 1 is a block diagram showing a light source according to a first embodiment.
[図 2]図 2Aは、電子放出素子の電極部分を示す平面図であり、図 2Bは、第 1の変形 例における電極部分を示す平面図である。  FIG. 2A is a plan view showing an electrode portion of an electron-emitting device, and FIG. 2B is a plan view showing an electrode portion in a first modification.
[図 3]図 3は、第 2の変形例における電極部分を示す平面図である。  FIG. 3 is a plan view showing an electrode portion in a second modification.
[図 4]図 4は、駆動回路から出力される駆動電圧を示す波形図である。  FIG. 4 is a waveform diagram showing a drive voltage output from the drive circuit.
[図 5]図 5は、第 1の実施の形態において、上部電極と下部電極間に電圧 Valを印加 した際の作用を示す説明図である。 [図 6]図 6は、上部電極と下部電極間に電圧 Va2を印加した際の電子放出作用を示 す説明図である。 FIG. 5 is an explanatory diagram showing an action when a voltage Val is applied between the upper electrode and the lower electrode in the first embodiment. [Fig. 6] Fig. 6 is an explanatory view showing an electron emission action when a voltage Va2 is applied between the upper electrode and the lower electrode.
[図 7]図 7は、ェミッタ部の表面での負極性帯電に伴って電子放出の自己停止の作用 を示す説明図である。  [FIG. 7] FIG. 7 is an explanatory view showing the self-stopping action of electron emission accompanying negative charge on the surface of the emitter section.
[図 8]図 8は、放出された 2次電子のエネルギーと 2次電子の放出量の関係を示す特 '性図である。  FIG. 8 is a characteristic diagram showing the relationship between the energy of emitted secondary electrons and the amount of secondary electrons emitted.
[図 9]図 9Aは、駆動電圧の一例を示す波形図であり、図 9Bは、第 1の実施の形態に 係る電子放出素子における下部電極と上部電極間の電圧の変化を示す波形図であ る。  FIG. 9A is a waveform diagram showing an example of a drive voltage, and FIG. 9B is a waveform diagram showing a change in voltage between the lower electrode and the upper electrode in the electron-emitting device according to the first embodiment. is there.
圆 10]図 10は、第 1の実施の形態に係る光源の第 1の変形例を示す構成図である。 圆 11]図 11は、第 1の実施の形態に係る光源の第 2の変形例を示す構成図である。 FIG. 10 is a block diagram showing a first modification of the light source according to the first embodiment. FIG. 11 is a configuration diagram showing a second modification of the light source according to the first embodiment.
[図 12]図 12は、駆動回路を示す回路図である。 FIG. 12 is a circuit diagram showing a drive circuit.
[図 13]図 13Aは点灯 Z消灯を示す制御信号を示す波形図であり、図 13Bはクロック を示す波形図であり、図 13Cはタイミングパルスを示す波形図であり、図 13Dは駆動 電圧生成回路にて生成された駆動電圧を示す波形図である。  [FIG. 13] FIG. 13A is a waveform diagram showing a control signal indicating ON / OFF, FIG. 13B is a waveform diagram showing a clock, FIG. 13C is a waveform diagram showing a timing pulse, and FIG. 13D is a drive voltage generator. It is a wave form diagram which shows the drive voltage produced | generated by the circuit.
圆 14]図 14は、駆動回路の好ましい実施の形態を概念的に示す回路図である。 14] FIG. 14 is a circuit diagram conceptually showing a preferred embodiment of the drive circuit.
[図 15]図 15は、駆動回路の動作を示す波形図である。 FIG. 15 is a waveform diagram showing the operation of the drive circuit.
圆 16]図 16は、第 1の実施の形態に係る光源の第 3の変形例を示す構成図である。 FIG. 16 is a configuration diagram showing a third modification of the light source according to the first embodiment.
[図 17]図 17は、第 3の変形例に係る光源に対応させた駆動回路の動作を示す波形 図である。 FIG. 17 is a waveform diagram showing the operation of the drive circuit corresponding to the light source according to the third modification.
圆 18]図 18は、変形例に係る駆動回路を示す回路図である。 [18] FIG. 18 is a circuit diagram showing a drive circuit according to a modification.
[図 19]図 19Aは調光信号を示す波形図であり、図 19Bは調光信号の電圧レベルに 応じて期間 T2を変調する方式を示す説明図であり、図 19Cは調光信号の電圧レべ ルに応じて電圧 Va2の印加期間（パルス幅）を変調する方式を示す説明図である。  FIG. 19A is a waveform diagram showing a dimming signal, FIG. 19B is an explanatory diagram showing a method of modulating the period T2 in accordance with the voltage level of the dimming signal, and FIG. 19C is a voltage diagram of the dimming signal. FIG. 6 is an explanatory diagram showing a method of modulating the application period (pulse width) of voltage Va2 according to the level.
[図 20]図 20は、電圧 Va2のパルス幅と輝度との関係を示す特性図である。  FIG. 20 is a characteristic diagram showing the relationship between the pulse width of voltage Va2 and luminance.
[図 21]図 21は、コレクタ電圧と輝度との関係を示す特性図である。  FIG. 21 is a characteristic diagram showing a relationship between collector voltage and luminance.
[図 22]図 22は、上部電極と下部電極間に印加する電圧 Va2 (電圧レベル）と輝度と の関係を示す特性図である。 [図 23]図 23は、上部電極と下部電極間に印加する電圧 Valと輝度との関係を示す 特性図である。 FIG. 22 is a characteristic diagram showing the relationship between the voltage Va2 (voltage level) applied between the upper electrode and the lower electrode and the luminance. FIG. 23 is a characteristic diagram showing the relationship between the voltage Val applied between the upper electrode and the lower electrode and the luminance.
圆 24]図 24は、第 1の実施の形態に係る光源の第 4の変形例を示す構成図である。 FIG. 24 is a configuration diagram showing a fourth modification of the light source according to the first embodiment.
[図 25]図 25は、第 4の変形例に係る光源の 1つの電子放出素子を取り出して示す構 成図である。 FIG. 25 is a configuration diagram showing one electron-emitting device of a light source according to a fourth modification.
[図 26]図 26は、図 25に示す電子放出素子について、上部電極とコレクタ電極との間 に流れる電流を主体にした等価回路を示す図である。  FIG. 26 is a diagram showing an equivalent circuit mainly composed of a current flowing between the upper electrode and the collector electrode in the electron-emitting device shown in FIG.
[図 27]図 27は、図 25に示す電子放出素子の出力特性 (Vkc— Ike特性)を示す図で ある。  FIG. 27 is a diagram showing output characteristics (Vkc-Ike characteristics) of the electron-emitting device shown in FIG.
[図 28]図 28は、上部電極とコレクタ電極間に制御電極を設置した場合において、コ レクタ電極に流れるコレクタ電流と制御電極に流れる制御電流を主体にした等価回 路を示す図である。  FIG. 28 is a diagram showing an equivalent circuit mainly composed of a collector current flowing through the collector electrode and a control current flowing through the control electrode when a control electrode is installed between the upper electrode and the collector electrode.
圆 29]図 29は、第 1の実施の形態に係る光源の第 5の変形例を示す構成図である。 圆 30]図 30は、第 1の実施の形態に係る光源の第 6の変形例を示す構成図である。 圆 31]図 31は、第 1の実施の形態に係る光源の第 7の変形例を示す構成図である。 圆 32]図 32は、第 1の実施の形態に係る光源の第 8の変形例を示す構成図である。 圆 33]図 33は、第 1の実施の形態に係る光源の第 9の変形例を示す構成図である。 圆 34]図 34は、第 1の実施の形態に係る光源の第 10の変形例を示す構成図である 圆 35]図 35は、第 1の実施の形態に係る光源の第 11の変形例を示す構成図である 圆 36]図 36は、第 1の実施の形態に係る光源の第 12の変形例を示す構成図である 圆 37]図 37は、第 1の実施の形態に係る光源の第 13の変形例を示す構成図である 29] FIG. 29 is a configuration diagram showing a fifth modification of the light source according to the first embodiment. FIG. 30 is a configuration diagram showing a sixth modification of the light source according to the first embodiment. [31] FIG. 31 is a configuration diagram showing a seventh modification of the light source according to the first embodiment. FIG. 32 is a configuration diagram showing an eighth modification of the light source according to the first embodiment. FIG. 33 is a configuration diagram showing a ninth modification of the light source according to the first embodiment. 34] FIG. 34 is a block diagram showing a tenth modification of the light source according to the first embodiment. [35] FIG. 35 shows an eleventh modification of the light source according to the first embodiment. FIG. 36 is a block diagram showing a twelfth modification of the light source according to the first embodiment. 1 37] FIG. 37 shows a light source according to the first embodiment. It is a block diagram which shows the 13th modification of
[図 38]図 38は、第 2の実施の形態に係る光源に使用される電子放出素子を一部省 略して示す断面図である。 FIG. 38 is a cross-sectional view showing a part of the electron-emitting device used in the light source according to the second embodiment.
[図 39]図 39は、電子放出素子の要部を拡大して示す断面図である。 [図 40]図 40は、上部電極に形成された貫通部の形状の一例を示す平面図である。 FIG. 39 is an enlarged cross-sectional view showing the main part of the electron-emitting device. FIG. 40 is a plan view showing an example of the shape of the through-hole formed in the upper electrode.
[図 41]図 41Aは上部電極の他の例を示す断面図であり、図 41Bは要部を拡大して 示す断面図である。 FIG. 41A is a cross-sectional view showing another example of the upper electrode, and FIG. 41B is a cross-sectional view showing an enlarged main part.
[図 42]図 42Aは上部電極のさらに他の例を示す断面図であり、図 42Bは要部を拡大 して示す断面図である。  FIG. 42A is a cross-sectional view showing still another example of the upper electrode, and FIG. 42B is a cross-sectional view showing an enlarged main part.
圆 43]図 43は、第 1の電子放出方式での駆動電圧の電圧波形を示す図である。 圆 44]図 44は、第 1の電子放出方式の第 2の出力期間での電子放出の様子を示す 説明図である。 [43] FIG. 43 is a diagram showing a voltage waveform of the drive voltage in the first electron emission method. [44] FIG. 44 is an explanatory view showing the state of electron emission in the second output period of the first electron emission method.
[図 45]図 45は、第 2の電子放出方式での駆動電圧の電圧波形を示す図である。  FIG. 45 is a diagram showing a voltage waveform of a drive voltage in the second electron emission method.
[図 46]図 46は、第 2の電子放出方式の第 2の出力期間での電子放出の様子を示す 説明図である。 FIG. 46 is an explanatory diagram showing a state of electron emission in the second output period of the second electron emission method.
[図 47]図 47は、上部電極の庇部の断面形状の一例を示す図である。  FIG. 47 is a diagram showing an example of a cross-sectional shape of a collar portion of the upper electrode.
[図 48]図 48は、上部電極の庇部の断面形状の他の例を示す図である。  FIG. 48 is a diagram showing another example of the cross-sectional shape of the collar portion of the upper electrode.
[図 49]図 49は、上部電極の庇部の断面形状のさらに他の例を示す図である。  FIG. 49 is a diagram showing still another example of the cross-sectional shape of the collar portion of the upper electrode.
[図 50]図 50は、上部電極と下部電極間に接続された各種コンデンサの接続状態を 示す等価回路図である。  FIG. 50 is an equivalent circuit diagram showing a connection state of various capacitors connected between the upper electrode and the lower electrode.
[図 51]図 51は、上部電極と下部電極間に接続された各種コンデンサの容量計算を 説明するための図である。  FIG. 51 is a diagram for explaining capacitance calculation of various capacitors connected between an upper electrode and a lower electrode.
[図 52]図 52は、第 2の実施の形態に係る光源に使用される電子放出素子の第 1の変 形例を一部省略して示す平面図である。  FIG. 52 is a plan view showing a part of the first modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 53]図 53は、第 2の実施の形態に係る光源に使用される電子放出素子の第 2の変 形例を一部省略して示す平面図である。  FIG. 53 is a plan view showing a part of the second modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 54]図 54は、第 2の実施の形態に係る光源に使用される電子放出素子の第 3の変 形例を一部省略して示す断面図である。  FIG. 54 is a cross-sectional view showing a part of the third modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 55]図 55は、第 2の実施の形態に係る光源に使用される電子放出素子の電圧ー電 荷量特性 (電圧一分極量特性)を示す図である。  FIG. 55 is a diagram showing a voltage-charge amount characteristic (voltage-polarization amount characteristic) of an electron-emitting device used in the light source according to the second embodiment.
[図 56]図 56Aは図 55のポイント piでの状態を示す説明図であり、図 56Bは図 55の ポイント p2での状態を示す説明図であり、図 56Cは図 55のポイント p2からポイント p3 に至るまでの状態を示す説明図である。 [FIG. 56] FIG. 56A is an explanatory diagram showing a state at point pi in FIG. 55, FIG. 56B is an explanatory diagram showing a state at point p2 in FIG. 55, and FIG. 56C is a point from point p2 in FIG. p3 It is explanatory drawing which shows the state until it reaches.
[図 57]図 57Aは図 55のポイント p3からポイント p4に至るまでの状態を示す説明図で あり、図 57Bは図 55のポイント p4に至る直前の状態を示す説明図であり、図 57Cは 図 55のポイント p4からポイント p6に至るまでの状態を示す説明図である。  [FIG. 57] FIG. 57A is an explanatory view showing a state from point p3 to point p4 in FIG. 55, FIG. 57B is an explanatory view showing a state immediately before reaching point p4 in FIG. 55, and FIG. FIG. 56 is an explanatory diagram showing a state from point p4 to point p6 in FIG. 55.
[図 58]図 58は、第 2の実施の形態に係る光源で使用される発光部と駆動回路を示す ブロック図である。 FIG. 58 is a block diagram showing a light emitting unit and a drive circuit used in the light source according to the second embodiment.
[図 59]図 59A—図 59Cは、振幅変調回路によるパルス信号の振幅変調を示す波形 図である。  FIG. 59A to FIG. 59C are waveform diagrams showing amplitude modulation of a pulse signal by the amplitude modulation circuit.
[図 60]図 60は、変形例に係る信号供給回路を示すブロック図である。  FIG. 60 is a block diagram showing a signal supply circuit according to a modification.
[図 61]図 61A—図 61Cは、パルス幅変調回路によるパルス信号のパルス幅変調を 示す波形図である。  FIG. 61A to FIG. 61C are waveform diagrams showing pulse width modulation of a pulse signal by a pulse width modulation circuit.
[図 62]図 62Aは図 59A又は図 61Aにおける電圧 Vslが印加されたときのヒステリシス 曲線を示す図であり、図 62Bは図 59B又は図 61Bにおける電圧 Vsmが印加されたと きのヒステリシス曲線を示す図であり、図 62Cは図 59C又は図 61Cにおける電圧 Vsh が印加されたときのヒステリシス曲線を示す図である。  FIG. 62A is a diagram showing a hysteresis curve when the voltage Vsl in FIG. 59A or 61A is applied, and FIG. 62B is a hysteresis curve when the voltage Vsm in FIG. 59B or 61B is applied. 62C is a diagram showing a hysteresis curve when the voltage Vsh in FIG. 59C or FIG. 61C is applied.
[図 63]図 63は、上部電極上へのコレクタ電極、蛍光体及び透明板の 1つの配置例を 示す構成図である。  FIG. 63 is a configuration diagram showing one arrangement example of the collector electrode, the phosphor, and the transparent plate on the upper electrode.
[図 64]図 64は、上部電極上へのコレクタ電極、蛍光体及び透明板の他の配置例を 示す構成図である。  FIG. 64 is a configuration diagram showing another arrangement example of the collector electrode, the phosphor, and the transparent plate on the upper electrode.
圆 65]図 65Aは第 1の実験例 (電子放出素子の電子の放出状態をみた実験）におい て使用した書込みパルスと点灯パルスの波形を示す図であり、図 65Bは第 1の実験 例において、電子放出素子からの電子放出の状態を受光素子の検出電圧波形で示 す図である。 圆 65] Fig. 65A is a diagram showing the waveforms of the write pulse and the lighting pulse used in the first experimental example (experiment of the electron emission state of the electron-emitting device), and Fig. 65B shows the waveform in the first experimental example. FIG. 6 is a diagram showing a state of electron emission from the electron-emitting device with a detection voltage waveform of the light-receiving device.
[図 66]図 66は、第 2—第 4の実験例で使用した書込みパルスと点灯パルスの波形を 示す図である。  [FIG. 66] FIG. 66 is a diagram showing waveforms of an address pulse and a lighting pulse used in the second to fourth experimental examples.
[図 67]図 67は、第 2の実験例 (電子放出素子の電子の放出量が書込みパルスの振 幅によってどのように変化するかをみた実験）の結果を示す特性図である。  FIG. 67 is a characteristic diagram showing the results of a second experimental example (an experiment that shows how the amount of electrons emitted from the electron-emitting device varies depending on the amplitude of the write pulse).
[図 68]図 68は、第 3の実験例（電子放出素子の電子の放出量が点灯パルスの振幅 によってどのように変化するかをみた実験）の結果を示す特性図である。 FIG. 68 shows a third experimental example (in which the amount of electrons emitted from the electron-emitting device is the amplitude of the lighting pulse) It is a characteristic view which shows the result of the experiment) which looked at how it changes with.
[図 69]図 69は、第 4の実験例（電子放出素子の電子の放出量がコレクタ電圧のレべ ルによってどのように変化するかをみた実験）の結果を示す特性図である。  [FIG. 69] FIG. 69 is a characteristic diagram showing the results of a fourth experimental example (an experiment in which the amount of electrons emitted from the electron-emitting device varies depending on the collector voltage level).
[図 70]図 70は、光源の駆動方法の一例を示すタイミングチャートである。  FIG. 70 is a timing chart showing an example of a light source driving method.
[図 71]図 71は、図 70に示す駆動方法での印加電圧関係を示す表図である。  71 is a table showing a relationship between applied voltages in the driving method shown in FIG. 70. FIG.
[図 72]図 72は、第 2の実施の形態に係る光源で使用される電子放出素子の第 1の変 形例を一部省略して示す断面図である。  FIG. 72 is a cross-sectional view showing a part of the first modification of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 73]図 73は、第 2の実施の形態に係る光源で使用される電子放出素子の第 2の変 形例を一部省略して示す断面図である。  FIG. 73 is a cross-sectional view showing a second modified example of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 74]図 74は、第 2の実施の形態に係る光源で使用される電子放出素子の第 3の変 形例を一部省略して示す断面図である。  FIG. 74 is a cross-sectional view showing a third variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 75]図 75は、第 2の実施の形態に係る光源で使用される電子放出素子の第 4の変 形例を一部省略して示す断面図である。  FIG. 75 is a cross-sectional view showing a fourth variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
[図 76]図 76は、第 2の実施の形態に係る光源で使用される電子放出素子の第 5の変 形例を一部省略して示す断面図である。  [FIG. 76] FIG. 76 is a cross-sectional view showing a partially modified fifth example of the electron-emitting device used in the light source according to the second embodiment.
[図 77]図 77は、第 2の実施の形態に係る光源で使用される電子放出素子の第 6の変 形例を一部省略して示す断面図である。  FIG. 77 is a cross-sectional view showing a sixth variation of the electron-emitting device used in the light source according to the second embodiment with a part thereof omitted.
符号の説明 Explanation of symbols
10A、 lOAa— 10Am、 10B…光源  10A, lOAa—10Am, 10B… Light source
12 A, 12Aa、 12Ab、 12B、 12Ba— 12Bf…電子放出素子  12 A, 12Aa, 12Ab, 12B, 12Ba— 12Bf ... Electron emitter
14、 14A、 14B…発光部  14, 14A, 14B ... Light emitting part
16、 16 A, 16Aaゝ 16Β· ··駆動回路  16, 16 A, 16 Aa ゝ 16 Β ... Drive circuit
18· ··上部電極 20· · -下部電極  18 ··· Upper electrode 20 · ·-Lower electrode
22…ェ ッタ咅 32· · 'コレクタ電極  22… Etta 咅 32 ·· 'Collector electrode
34…蛍光体 40· · -水銀粒子  34… Phosphor 40 · -Mercury particles
44…タイミング発生回路 46· · -駆動電圧生成回路  44… Timing generator 46 ·· -Drive voltage generator
50…電力回収回路 60· · -変調回路  50 ... Power recovery circuit 60 ·· -Modulation circuit
102…貫通部 104 …凹凸 106· ' '·凹部 108· · -庇部 102 ... penetrating part 104 ... uneven 106 '''Recess 108 · ·-Buttocks
110· ' '·ギャップ 112· '凸部  110 · '' · Gap 112 · 'Convex
114· ' '·孔 116· · '鱗片状の形状を有する物質  114 · '············' Scaly substance
118、 122…集合体 120· 導電性の物質  118, 122 ... Aggregate 120 · Conductive substance
128· ' -切欠き 132· "スリット  128 · '-Notch 132 · "Slit
134· ' '·フローティング電極  134 · '' Floating electrode
発明を実施するための最良の形態  BEST MODE FOR CARRYING OUT THE INVENTION
[0044] 以下、本発明に係る光源の実施の形態例を図 1一図 77を参照しながら説明する。  Hereinafter, an embodiment of a light source according to the present invention will be described with reference to FIGS.
[0045] 第 1の実施の形態に係る光源 10Aは、図 1に示すように、複数の電子放出素子 12 Aが二次元的に配列された発光部 14Aと、該発光部 14Aの各電子放出素子 12Aに 対して駆動電圧 Vaを印加する駆動回路 16Aとを有する。  As shown in FIG. 1, the light source 10A according to the first embodiment includes a light emitting unit 14A in which a plurality of electron emitting elements 12A are two-dimensionally arranged, and each electron emission of the light emitting unit 14A. And a drive circuit 16A for applying a drive voltage Va to the element 12A.
[0046] 駆動回路 16Aは、外部（点灯 Z消灯スィッチ等)からの点灯 Z消灯を示す制御信 号 Scに基づいて、各電子放出素子 12Aの第 1の電極 (例えば上部電極） 18及び第 2の電極（下部電極） 20に駆動電圧 Vaを印加して、各電子放出素子 12Aを駆動制 御する。駆動回路 16 Aの好ま 、例につ 、ては後述する。  The drive circuit 16A includes a first electrode (for example, an upper electrode) 18 and a second electrode of each electron-emitting device 12A based on a control signal Sc indicating lighting Z extinction from the outside (lighting Z extinction switch or the like). A drive voltage Va is applied to the electrode (lower electrode) 20 to control the drive of each electron-emitting device 12A. An example of the driving circuit 16A will be described later.
[0047] 各電子放出素子 12Aは、図 1に示すように、板状のェミッタ部 22と、該ェミッタ部 22 の表面に形成された前記上部電極 18と、ェミッタ部 22の裏面に形成された前記下 部電極 20とを有する。このように、電子放出素子 12Aは、ェミッタ部 22を上部電極 1 8と下部電極 20でサンドイッチした構造となっているため、容量性負荷となる。従って 、この電子放出素子 12Aは一種のコンデンサ C (図 12参照）としてみることができる。  As shown in FIG. 1, each electron-emitting device 12A is formed on a plate-like emitter portion 22, the upper electrode 18 formed on the surface of the emitter portion 22, and the back surface of the emitter portion 22. And the lower electrode 20. Thus, since the electron emitter 12A has a structure in which the emitter 22 is sandwiched between the upper electrode 18 and the lower electrode 20, it becomes a capacitive load. Therefore, the electron-emitting device 12A can be viewed as a kind of capacitor C (see FIG. 12).
[0048] 上部電極 18と下部電極 20間には、駆動回路 16Aからの駆動電圧 Vaが印加される 。図 1の例では、下部電極 20を抵抗 R1を介して GND (グランド）に接続することによ り、該下部電極 20の電位をゼロにした場合を示している力 もちろん、ゼロ電位以外 の電位にしてもかまわない。なお、上部電極 18と下部電極 20間への駆動電圧 Vaの 印加は、例えば図 2A及び図 2Bに示すように、上部電極 18に延びるリード電極 24と 下部電極 20に延びるリード電極 26を通じて行われる。  [0048] A drive voltage Va from the drive circuit 16A is applied between the upper electrode 18 and the lower electrode 20. In the example of FIG. 1, a force is shown when the potential of the lower electrode 20 is made zero by connecting the lower electrode 20 to the GND (ground) via the resistor R1. It doesn't matter. The application of the driving voltage Va between the upper electrode 18 and the lower electrode 20 is performed through a lead electrode 24 extending to the upper electrode 18 and a lead electrode 26 extending to the lower electrode 20 as shown in FIGS. 2A and 2B, for example. .
[0049] そして、図 1に示すように、この電子放出素子 12Aを光源として利用する場合は、上 部電極 18の上方に、例えばガラスやアクリル製の透明板 30が配置され、該透明板 3 0の裏面（上部電極 18と対向する面）に、例えば透明電極にて構成されたコレクタ電 極 32が配置され、該コレクタ電極 32には蛍光体 34が塗布される。なお、コレクタ電 極 32にはバイアス電源 36 (バイアス電圧 Vc)が抵抗 R2を介して接続される。 [0049] As shown in FIG. 1, when the electron-emitting device 12A is used as a light source, a transparent plate 30 made of, for example, glass or acrylic is disposed above the upper electrode 18, and the transparent plate 3 A collector electrode 32 made of, for example, a transparent electrode is disposed on the back surface of 0 (the surface facing the upper electrode 18), and a phosphor 34 is applied to the collector electrode 32. A bias power source 36 (bias voltage Vc) is connected to the collector electrode 32 via a resistor R2.
[0050] また、電子放出素子 12Aは、当然のことながら、真空空間内に配置される。この電 子放出素子 12Aは、図 1に示すように、電界集中ポイント Aが存在する力 ポイント A は、上部電極 18/ェミッタ部 22/真空が 1つのポイントに存在する 3重点を含むボイ ントとしても定義することができる。  [0050] The electron-emitting device 12A is, of course, arranged in the vacuum space. As shown in FIG. 1, the electron emission element 12A has a force point A where the electric field concentration point A exists as a point including a triple point where the upper electrode 18 / emitter 22 / vacuum exists at one point. Can also be defined.
[0051] そして、雰囲気中の真空度は、 102— 10— 6Paが好ましぐより好ましくは 10— 3— 10— 5P aである。 [0051] Then, the vacuum level in the atmosphere, 10 2 - 10 6, more preferably Pa is preferred instrument 10 3 - 10 5 P a.
[0052] このような範囲を選んだ理由は、低真空では、（1)空間内に気体分子が多いため、 プラズマを生成し易ぐプラズマが多量に発生され過ぎると、その正イオンが多量に 上部電極 18に衝突して損傷を進めるおそれや、（2)放出電子がコレクタ電極 32に到 達する前に気体分子に衝突してしま 、、コレクタ電位 (Vc)で十分に加速した電子に よる蛍光体 34の励起が十分に行われなくなるおそれがあるからである。  [0052] The reason for selecting such a range is that, in a low vacuum, (1) because there are many gas molecules in the space, if too much plasma that easily generates plasma is generated too much, a large amount of positive ions There is a risk of colliding with the upper electrode 18 to promote damage, or (2) fluorescence emitted by electrons sufficiently accelerated by the collector potential (Vc) when colliding with gas molecules before the emitted electrons reach the collector electrode 32. This is because the body 34 may not be sufficiently excited.
[0053] 一方、高真空では、電界集中ポイント Aから電子を放出し易いものの、構造体の支 持、及び真空のシール部が大きくなり、小型化に不利になるという問題があるからで ある。  [0053] On the other hand, in a high vacuum, electrons are likely to be emitted from the electric field concentration point A, but there is a problem in that the structure support and the vacuum seal portion become large, which is disadvantageous for miniaturization.
[0054] ここで、ェミッタ部 22は誘電体にて構成される。誘電体は、好適には、比誘電率が 比較的高い、例えば 1000以上の誘電体を採用することができる。このような誘電体と しては、チタン酸バリウムのほかに、ジルコン酸鉛、マグネシウムニオブ酸鉛、 -ッケ ルニオブ酸鈴、亜鉛ニオブ酸鉛、マンガンニオブ酸鉛、マグネシウムタンタル酸鉛、 ニッケルタンタル酸鉛、アンチモンスズ酸鉛、チタン酸鉛、マグネシウムタングステン 酸鉛、コバルトニオブ酸鉛等、又はこれらの任意の組み合わせを含有するセラミック スゃ、主成分力 Sこれらの化合物を 50重量％以上含有するものや、前記セラミックスに 対して更にランタン、カルシウム、ストロンチウム、モリブデン、タングステン、ノ リウム、 ニオブ、亜鉛、ニッケル、マンガン等の酸化物、もしくはこれらのいずれかの組み合わ せ、又は他の化合物を適切に添加したもの等を挙げることができる。  Here, the emitter 22 is made of a dielectric. As the dielectric, a dielectric having a relatively high relative dielectric constant, for example, 1000 or more can be used. In addition to barium titanate, such dielectrics include lead zirconate, lead magnesium niobate, -keckle niobate bell, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, nickel tantalum. Ceramic containing lead acid, lead antimony stannate, lead titanate, magnesium tungstate lead, lead cobalt niobate, etc., or any combination thereof, main component S containing 50% by weight or more of these compounds Lanthanum, calcium, strontium, molybdenum, tungsten, norium, niobium, zinc, nickel, manganese, etc., or any combination of these, or other compounds are appropriately applied to the above-mentioned ceramics. The added one can be mentioned.
[0055] 例えば、マグネシウムニオブ酸鉛（PMN)とチタン酸鉛（PT)の 2成分系 nPMN— m PT(n, mをモル数比とする）においては、 PMNのモル数比を大きくすると、キュリー 点が下げられて、室温での比誘電率を大きくすることができる。 [0055] For example, two-component system of lead magnesium niobate (PMN) and lead titanate (PT) nPMN-m In PT (where n and m are mole ratios), increasing the PMN mole ratio can lower the Curie point and increase the dielectric constant at room temperature.
[0056] 特に、 n=0. 85-1. 0、 m= l. 0— nでは比誘電率 3000以上となり好ましい。例え ば、、 n=0. 91、 m=0. 09で ίま室温の it誘電率 15000力得られ、 n=0. 95、 m=0 . 05では室温の比誘電率 20000が得られる。  [0056] Particularly, n = 0.85-1.0 and m = l.0-n are preferable because the relative dielectric constant is 3000 or more. For example, when n = 0.91 and m = 0.09, it is possible to obtain an it permittivity of 15000 at room temperature, and when n = 0.95 and m = 0.05, a relative permittivity of 20000 at room temperature is obtained.
[0057] 次に、マグネシウムニオブ酸鉛（PMN)、チタン酸鉛（PT)、ジルコン酸鉛 (PZ)の 3 成分系では、 PMNのモル数比を大きくする他に、正方晶と擬立方晶又は正方晶と 菱面体晶のモルフオト口ピック相境界（MPB： MorphotropicPhase Boundary)付近の 組成とすることが比誘電率を大きくするのに好ましい。例えば、 PMN : PT: PZ = 0. 3 75 : 0. 375 : 0. 25【こて it誘電率 5500、 PMN : PT: PZ = 0. 5 : 0. 375 : 0. 125【こ て比誘電率 4500となり、特に好ましい。更に、絶縁性が確保できる範囲内でこれらの 誘電体に白金のような金属を混入して、誘電率を向上させるのが好ましい。この場合 、例えば、誘電体に白金を重量比で 20%混入させるとよい。  [0057] Next, in the three-component system of lead magnesium niobate (PMN), lead titanate (PT), and lead zirconate (PZ), in addition to increasing the molar ratio of PMN, tetragonal and pseudocubic crystals Alternatively, a composition in the vicinity of a morphotropic phase boundary (MPB) between tetragonal and rhombohedral is preferable for increasing the relative dielectric constant. For example, PMN: PT: PZ = 0.3 75: 0. 375: 0.25 [trowel it dielectric constant 5500, PMN: PT: PZ = 0.5: 0. 375: 0.125 The rate is 4500, which is particularly preferable. Furthermore, it is preferable to improve the dielectric constant by mixing a metal such as platinum into these dielectrics within a range that can ensure insulation. In this case, for example, 20% by weight of platinum may be mixed in the dielectric.
[0058] また、ェミッタ部 22は、上述したように、圧電 Z電歪層や反強誘電体層等を用いる ことができるが、ェミッタ部 22として圧電 Z電歪層を用いる場合、該圧電 Z電歪層と しては、例えば、ジルコン酸鉛、マグネシウムニオブ酸鉛、ニッケルニオブ酸鉛、亜鉛 ニオブ酸鉛、マンガンニオブ酸鉛、マグネシウムタンタル酸鉛、ニッケルタンタル酸鉛 、アンチモンスズ酸鈴、チタン酸鈴、チタン酸バリウム、マグネシウムタングステン酸鈴 、コバルトニオブ酸鈴等、又はこれらのいずれかの組み合わせを含有するセラミックス が挙げられる。  Further, as described above, a piezoelectric Z electrostrictive layer, an antiferroelectric layer, or the like can be used for the emitter section 22. However, when a piezoelectric Z electrostrictive layer is used as the emitter section 22, the piezoelectric Z Examples of electrostrictive layers include lead zirconate, lead magnesium niobate, lead nickel niobate, lead zinc niobate, lead manganese niobate, lead magnesium tantalate, lead nickel tantalate, antimony stannate, titanium Ceramics containing an acid bell, barium titanate, magnesium tungstic acid bell, cobalt niobate bell or the like, or any combination thereof.
[0059] 主成分力 Sこれらの化合物を 50重量％以上含有するものであってもよ 、ことは 、うま でもない。また、前記セラミックスのうち、ジルコン酸鉛を含有するセラミックスは、エミ ッタ部 22を構成する圧電 Z電歪層の構成材料として最も使用頻度が高い。  [0059] Principal component strength S The compound may contain 50% by weight or more of these compounds. Among the ceramics, a ceramic containing lead zirconate is most frequently used as a constituent material of the piezoelectric Z electrostrictive layer constituting the emitter section 22.
[0060] また、圧電 Z電歪層をセラミックスにて構成する場合、前記セラミックスに、更に、ラ ンタン、カルシウム、ストロンチウム、モリブデン、タングステン、ノ リウム、ニオブ、亜鉛 、ニッケル、マンガン等の酸化物、もしくはこれらのいずれかの組み合わせ、又は他 の化合物を、適宜、添加したセラミックスを用いてもよい。また、前記セラミックスに Si O、 CeO、 Pb Ge O もしくはこれらのいずれかの組み合わせを添カ卩したセラミック スを用いてもよい。具体的には、 PT— PZ—PMN系圧電材料に SiOを 0. 2wt%、も [0060] When the piezoelectric Z electrostrictive layer is formed of ceramics, the ceramics may further include oxides such as lanthanum, calcium, strontium, molybdenum, tungsten, norium, niobium, zinc, nickel, manganese, Alternatively, a ceramic obtained by appropriately adding any combination of these or other compounds may be used. In addition, ceramics with Si O, CeO, Pb Ge O or any combination thereof added to the ceramics. May be used. Specifically, 0.2 wt% of SiO is added to PT-PZ-PMN piezoelectric material.
2  2
しくは CeOを 0. lwt%、もしくは Pb Ge O を 1一 2wt%添カ卩した材料が好ましい。  A material containing 0.1 wt% CeO or 1 to 2 wt% Pb Ge 2 O is preferred.
2 5 3 11  2 5 3 11
[0061] 例えば、マグネシウムニオブ酸鉛とジルコン酸鉛及びチタン酸鉛とからなる成分を 主成分とし、更にランタンやストロンチウムを含有するセラミックスを用いることが好まし い。  [0061] For example, it is preferable to use a ceramic containing lead magnesium niobate, lead zirconate and lead titanate as main components and further containing lanthanum or strontium.
[0062] 圧電 Z電歪層は、緻密であっても、多孔質であってもよぐ多孔質の場合、その気 孔率は 40%以下であることが好まし 、。  [0062] When the piezoelectric Z electrostrictive layer is dense or porous, its porosity is preferably 40% or less.
[0063] ェミッタ部 22として反強誘電体層を用いる場合、該反強誘電体層としては、ジルコ ン酸鉛を主成分とするもの、ジルコン酸鉛とスズ酸鉛とからなる成分を主成分とするも の、更にはジルコン酸鈴に酸ィ匕ランタンを添カ卩したもの、ジルコン酸鈴とスズ酸鈴とか らなる成分に対してジルコン酸鉛やニオブ酸鉛を添加したものが望ましい。  [0063] When an antiferroelectric layer is used as the emitter section 22, the antiferroelectric layer is mainly composed of lead zirconate as a main component, or a component composed of lead zirconate and lead stannate. However, it is desirable to add a lanthanum acid zirconate to a zirconate bell, or to a component composed of a zirconate bell and a tin stannate to which lead zirconate or lead niobate is added.
[0064] また、この反強誘電体膜は、多孔質であってもよぐ多孔質の場合、その気孔率は 3 0%以下であることが望まし 、。  [0064] In addition, when the antiferroelectric film is porous, the porosity is preferably 30% or less.
[0065] さらに、ェミッタ部 22にタンタル酸ビスマス酸ストロンチウム（SrBi Ta O )を用いた  [0065] Further, strontium bismutanoate tantalate (SrBiTaO) was used for the emitter section 22.
2 2 9 場合、分極反転疲労が小さく好ましい。このような分極反転疲労が小さい材料は、層 状強誘電体化合物で、 (BiO ) 2+ (A B O ) 2という一般式で表される。ここで、金 In the case of 2 2 9, polarization inversion fatigue is small and preferable. Such a material with low polarization reversal fatigue is a layered ferroelectric compound and is represented by the general formula (BiO 2 ) 2 + (ABO 2 ) 2 . Where gold
2 m-1 m 3m+l  2 m-1 m 3m + l
属 Aのイオンは、 Ca2+、 Sr2+、 Ba Pb2+、 Bi3+、 La3+等であり、金属 Bのイオンは、 Ti4+ 、 Ta5+、 Nb5+等である。さらに、チタン酸バリウム系、ジルコン酸鉛系、 PZT系の圧電 セラミックスに添加剤を加えて半導体ィ匕させることも可能である。この場合、ェミッタ部 22内で不均一な電界分布をもたせて、電子放出に寄与する上部電極 18との界面近 傍に電界集中を行うことが可能となる。 The ions of genus A are Ca 2+ , Sr 2+ , Ba Pb 2+ , Bi 3+ , La 3+ etc., and the ions of metal B are Ti 4+ , Ta 5+ , Nb 5+ etc. . It is also possible to add semiconductors to semiconductors by adding additives to barium titanate, lead zirconate, and PZT piezoelectric ceramics. In this case, the electric field concentration can be performed in the vicinity of the interface with the upper electrode 18 that contributes to electron emission by providing a non-uniform electric field distribution in the emitter section 22.
[0066] また、圧電 Z電歪 Z反強誘電体セラミックスに、例えば鉛ホウケィ酸ガラス等のガラ ス成分や、他の低融点化合物（例えば酸ィ匕ビスマス等）を混ぜることによって、焼成 温度を下げることができる。  [0066] In addition, by mixing a piezoelectric Z electrostrictive Z antiferroelectric ceramic with a glass component such as lead borosilicate glass and other low melting point compounds (for example, bismuth oxide), the firing temperature is reduced. Can be lowered.
[0067] また、圧電 Z電歪 Z反強誘電体セラミックスで構成する場合、その形状はシート状 の成形体、シート状の積層体、あるいは、これらを他の支持用基板に積層又は接着 したものであってもよい。  [0067] Also, when the piezoelectric Z electrostrictive Z antiferroelectric ceramics is used, the shape thereof is a sheet-like molded body, a sheet-like laminated body, or a laminate or adhesion of these to another supporting substrate. It may be.
[0068] また、ェミッタ部 22に非鉛系の材料を使用する等により、ェミッタ部 22を融点もしく は蒸散温度の高い材料とすることで、電子もしくはイオンの衝突に対し損傷しにくくな る。 [0068] Further, by using a lead-free material for the emitter portion 22, the emitter portion 22 has a higher melting point. By using a material with a high transpiration temperature, it is less likely to be damaged by electron or ion collisions.
[0069] そして、ェミッタ部 22を形成する方法としては、スクリーン印刷法、デイツビング法、 塗布法、電気泳動法、エアロゾルデポジション法等の各種厚膜形成法や、イオンビ ーム法、スパッタリング法、真空蒸着法、イオンプレーティング法、化学気相成長法（ CVD)、めっき等の各種薄膜形成法を用いることができる。特に、圧電 Z電歪材料の 粉末ィ匕したものを、ェミッタ部 22として形成し、これに低融点のガラスゃゾル粒子を含 浸する方法をとることが好ましい。この手法により、 700°Cあるいは 600°C以下といつ た低温での膜形成が可能となる。  [0069] As a method of forming the emitter section 22, various thick film forming methods such as a screen printing method, a dating method, a coating method, an electrophoresis method, an aerosol deposition method, an ion beam method, a sputtering method, Various thin film forming methods such as vacuum deposition, ion plating, chemical vapor deposition (CVD), and plating can be used. In particular, it is preferable to use a method in which a powdered piezoelectric Z electrostrictive material is formed as the emitter portion 22 and impregnated with glass sol particles having a low melting point. This technique makes it possible to form a film at a low temperature of 700 ° C or below 600 ° C.
[0070] ここで、上部電極 18と下部電極 20間のェミッタ部 22の厚さ d (図 1参照）の大きさに ついて説明すると、上部電極 18と下部電極 20間の電圧 (駆動回路 16Aから出力さ れる駆動電圧 Vaが上部電極 18と下部電極 20間に印加されることによって、該上部 電極 18と下部電極 20間に現れる電圧）を Vakとしたとき、 E=VakZdで表される電 界 Eで分極反転あるいは分極変化が行われるように、前記厚さ dを設定することが好 ましい。つまり、前記厚さ dが小さいほど、低電圧で分極反転あるいは分極変化が可 能となり、低電圧駆動 (例えば 100V未満)で電子放出が可能となる。  Here, the size of the thickness d (see FIG. 1) of the emitter 22 between the upper electrode 18 and the lower electrode 20 will be described. The voltage between the upper electrode 18 and the lower electrode 20 (from the drive circuit 16A) When the output drive voltage Va is applied between the upper electrode 18 and the lower electrode 20 and the voltage appearing between the upper electrode 18 and the lower electrode 20 is Vak, the electric field expressed by E = VakZd It is preferable to set the thickness d so that polarization inversion or polarization change occurs at E. That is, as the thickness d is smaller, polarization inversion or polarization change is possible at a low voltage, and electrons can be emitted at a low voltage drive (for example, less than 100 V).
[0071] 上部電極 18は、以下に示す材料にて構成される。即ち、スパッタ率が小さぐ真空 中での蒸発温度が大きい導体が好ましい。例えば、 Ar+で 600Vにおけるスパッタ率 が 2. 0以下で、蒸気圧 1. 3 X 10— 3Paとなる温度が 1800K以上のものが好ましぐ白 金、モリブデン、タングステン等がこれに該当する。また、高温酸化雰囲気に対して耐 性を有する導体、例えば金属単体、合金、絶縁性セラミックスと金属単体との混合物 、絶縁性セラミックスと合金との混合物等によって構成され、好適には、白金、イリジゥ ム、パラジウム、ロジウム、モリブデン等の高融点貴金属や、銀-パラジウム、銀-白金 、白金 パラジウム等の合金を主成分とするものや、白金とセラミック材料とのサーメッ ト材料によって構成される。更に好適には、白金のみ又は白金系の合金を主成分と する材料によって構成される。また、電極として、カーボン、グラフアイト系の材料、例 えば、ダイヤモンド薄膜、ダイヤモンドライクカーボン、カーボンナノチューブも好適に 使用される。なお、電極材料中に添加されるセラミック材料の割合は、 5— 30体積％ 程度が好適である。 The upper electrode 18 is made of the following material. That is, a conductor having a low evaporation rate and a high evaporation temperature in a vacuum is preferable. For example, the sputtering rate at 600V with Ar + is 2. 0 or less, the temperature at which the vapor pressure 1. 3 X 10- 3 Pa is preferred instrument platinum is more than 1800 K, molybdenum, tungsten, or the like corresponds to this. Further, it is composed of a conductor having resistance to a high-temperature oxidizing atmosphere, such as a simple metal, an alloy, a mixture of insulating ceramics and a simple metal, a mixture of insulating ceramics and an alloy, and preferably platinum, iridium. It is composed of refractory precious metals such as silver, palladium, rhodium, molybdenum, etc., silver-palladium, silver-platinum, platinum-palladium and other cermet materials of platinum and ceramic materials. More preferably, it is composed of a material mainly composed of platinum or a platinum-based alloy. As the electrode, carbon or graphite-based materials such as diamond thin film, diamond-like carbon, and carbon nanotubes are also preferably used. The ratio of ceramic material added to the electrode material is 5-30% by volume. The degree is preferred.
[0072] 更に、焼成後に薄い膜が得られる有機金属ペースト、例えば白金レジネートペース ト等の材料を用いることが好ましい。また、分極反転疲労を抑制する酸化物電極、例 えば酸化ルテニウム、酸化イリジウム、ルテニウム酸ストロンチウム、 La Sr CoO (例 l-x x 3 えば x=0. 3や 0. 5)、 La Ca MnO、 La Ca Mn Co O (例えば x=0. 2、 y= l-x x 3 l-x x 1-y y 3  [0072] Further, it is preferable to use an organic metal paste capable of obtaining a thin film after firing, such as a platinum resinate paste. Also, oxide electrodes that suppress polarization reversal fatigue such as ruthenium oxide, iridium oxide, strontium ruthenate, La Sr CoO (e.g. lx x 3 x = 0.3 and 0.5), La Ca MnO, La Ca Mn Co O (e.g. x = 0.2, y = lx x 3 lx x 1-yy 3
0. 05)、もしくはこれらを例えば白金レジネートペーストに混ぜたものが好ましい。  0.05), or a mixture of these with, for example, a platinum resinate paste.
[0073] 上部電極 18は、上記材料を用いて、スクリーン印刷、スプレー、コーティング、ディ ッビング、塗布、電気泳動法等の各種の厚膜形成法や、スパッタリング法、イオンビ ーム法、真空蒸着法、イオンプレーティング法、化学気相成長法 (CVD)、めっき等 の各種の薄膜形成法による通常の膜形成法に従って形成することができ、好適には 、前者の厚膜形成法によって形成するとよい。 [0073] The upper electrode 18 is made of the above-described materials using various thick film forming methods such as screen printing, spraying, coating, dubbing, coating, and electrophoresis, sputtering, ion beam, and vacuum deposition. , Ion plating, chemical vapor deposition (CVD), and various other thin film formation methods such as plating, can be formed according to a normal film formation method, preferably the former thick film formation method .
[0074] 上部電極 18の平面形状は、図 2Aに示すように、楕円形状としてもよいし、図 2Bに 示す第 1の変形例に係る電子放出素子 12Aaのように、リング状にしてもよい。あるい は、図 3に示す第 2の変形例に係る電子放出素子 12Abのように、くし歯状にしてもよ い。 The planar shape of the upper electrode 18 may be an elliptical shape as shown in FIG. 2A, or may be a ring shape like the electron-emitting device 12Aa according to the first modification shown in FIG. 2B. . Or, it may be comb-like like the electron-emitting device 12Ab according to the second modification shown in FIG.
[0075] 上部電極 18の平面形状をリング状やくし歯状にすることによって、電界集中ポイン ト Aでもある上部電極 18Zェミッタ部 22Z真空の 3重点が増え、電子放出効率を向 上させることができる。  [0075] By making the planar shape of the upper electrode 18 into a ring-shaped comb shape, the triple point of the upper electrode 18Z emitter 22Z vacuum, which is also the electric field concentration point A, can be increased, and the electron emission efficiency can be improved. .
[0076] 上部電極 18の厚み tc (図 1参照）は、 20 m以下がよぐ好適には 5 m以下であ るとよい。従って、上部電極 18の厚み tcを lOOnm以下にしてもよい。上部電極 18の 厚み tcを極薄（10nm以下）とした場合には、該上部電極 18とェミッタ部 22との界面 力 電子が放出されることになり、電子放出効率を更に向上させることができる。  [0076] The thickness tc (see FIG. 1) of the upper electrode 18 is preferably 20 m or less, and more preferably 5 m or less. Therefore, the thickness tc of the upper electrode 18 may be less than lOOnm. When the thickness tc of the upper electrode 18 is extremely thin (10 nm or less), the interfacial force electrons between the upper electrode 18 and the emitter 22 are emitted, and the electron emission efficiency can be further improved. .
[0077] 一方、下部電極 20は、上部電極 18と同様の材料及び方法によって形成されるが、 好適には上記厚膜形成法によって形成する。下部電極 20の厚さも、 20 m以下で あるとよく、好適には 5 μ m以下であるとよい。  On the other hand, the lower electrode 20 is formed by the same material and method as the upper electrode 18, but is preferably formed by the thick film forming method. The thickness of the lower electrode 20 is also preferably 20 m or less, and preferably 5 μm or less.
[0078] ェミッタ部 22、上部電極 18及び下部電極 20をそれぞれ形成するたびに熱処理（ 焼成処理)することで、一体構造にすることができる。なお、上部電極 18及び下部電 極 20の形成方法によっては、一体化のための熱処理 (焼成処理)を必要としない場 合もある。 [0078] A heat treatment (firing treatment) is performed each time the emitter section 22, the upper electrode 18, and the lower electrode 20 are formed, whereby an integrated structure can be obtained. Depending on the method of forming the upper electrode 18 and the lower electrode 20, a heat treatment (firing process) for integration may not be required. Sometimes.
[0079] ェミッタ部 22、上部電極 18及び下部電極 20とを一体ィ匕させるための焼成処理に 係る温度としては、 500— 1400°Cの範囲、好適には、 1000— 1400°Cの範囲とする とよい。更に、膜状のェミッタ部 22を熱処理する場合、高温時にェミッタ部 22の組成 が不安定にならな 、ように、ェミッタ部 22の蒸発源と共に雰囲気制御を行 、ながら焼 成処理を行うことが好まし 、。  [0079] The temperature related to the firing treatment for integrating the emitter section 22, the upper electrode 18 and the lower electrode 20 together is in the range of 500-1400 ° C, preferably in the range of 1000-1400 ° C. It is good to do. Further, when the film-like emitter 22 is heat-treated, the firing process can be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the composition of the emitter 22 is not unstable at high temperatures. I like it.
[0080] また、ェミッタ部 22を適切な部材によって被覆し、ェミッタ部 22の表面が焼成雰囲 気に直接露出しな 、ようにして焼成する方法を採用してもよ 、。  [0080] Alternatively, a method may be employed in which the emitter portion 22 is covered with an appropriate member and the surface of the emitter portion 22 is not directly exposed to the firing atmosphere.
[0081] 次に、電子放出素子 12Aの電子放出原理について図 1、図 4一図 9Bを参照しなが ら説明する。先ず、駆動回路 16Aから出力される駆動電圧 Vaは、図 4に示すように、 上部電極 18の電位が下部電極 20の電位よりも高い電圧 Valが出力される期間 T1と 、上部電極 18の電位が下部電極 20の電位よりも低 ヽ電圧 Va2が出力される期間 T2 とが繰り返される。ここで、期間 T2で出力される電圧 Va2を駆動パルス Pdと記す。  Next, the principle of electron emission of the electron-emitting device 12A will be described with reference to FIGS. 1, 4 and 9B. First, as shown in FIG. 4, the drive voltage Va output from the drive circuit 16A has a period T1 during which a voltage Val is output in which the potential of the upper electrode 18 is higher than the potential of the lower electrode 20, and the potential of the upper electrode 18 The period T2 during which a voltage Va2 lower than the potential of the lower electrode 20 is output is repeated. Here, voltage Va2 output in period T2 is referred to as drive pulse Pd.
[0082] 駆動パルス Pdの振幅 Vinは、電圧 Val力 電圧 Va2を差し引いた値（=Val— Va 2)で定義することができる。  The amplitude Vin of the drive pulse Pd can be defined by a value obtained by subtracting the voltage Val force voltage Va2 (= Val−Va 2).
[0083] 期間 T1は、図 5に示すように、上部電極 18と下部電極 20間に電圧 Valを印加して ェミッタ部 22を分極する期間である。電圧 Valとしては、図 4に示すように直流電圧 でもよいが、 1つのパルス電圧もしくはパルス電圧を複数回連続印加するようにしても よい。ここで、期間 T1は、分極処理を十分に行うために、期間 T2よりも長くとることが 好ましい。例えば、この期間 T1としては 100 sec以上が好ましい。これは、電圧 Va 1の印加時の消費電力及び上部電極 18の損傷を防止する目的で、分極を行うため の電圧 Valの絶対値を、電圧 Va2の絶対値よりも小さく設定しているからである。  As shown in FIG. 5, the period T 1 is a period in which the voltage Val is applied between the upper electrode 18 and the lower electrode 20 to polarize the emitter section 22. The voltage Val may be a DC voltage as shown in FIG. 4, but one pulse voltage or a pulse voltage may be applied continuously several times. Here, the period T1 is preferably longer than the period T2 in order to sufficiently perform the polarization process. For example, the period T1 is preferably 100 seconds or longer. This is because the absolute value of the voltage Val for polarization is set smaller than the absolute value of the voltage Va2 for the purpose of preventing power consumption when the voltage Va 1 is applied and damage to the upper electrode 18. is there.
[0084] また、電圧 Val及び Va2は、各々正負の極性に分極処理を確実に行うことが可能 な電圧レベルであることが好ましぐ例えばェミッタ部 22の誘電体が抗電圧を有する 場合、電圧 Val及び Va2の絶対値は、抗電圧以上であることが好ましい。  [0084] In addition, it is preferable that the voltages Val and Va2 are voltage levels that can positively and negatively polarize each other. For example, when the dielectric of the emitter 22 has a coercive voltage, The absolute values of Val and Va2 are preferably not less than the coercive voltage.
[0085] そして、上部電極 18と下部電極 20間に所定レベルの振幅を有する駆動パルス Pd が印加されることによって、図 6に示すように、少なくともェミッタ部 22の一部が分極反 転あるいは分極変化される。ここで、分極反転あるいは分極変化される部位は、上部 電極 18の真下部分はもちろんのこと、真上に上部電極 18を有しておらず、表面が露 出した部分についても、上部電極 18の近傍では、同様に分極反転あるいは分極変 化が行われる。つまり、上部電極 18の近傍で、ェミッタ部 22の表面が露出した部分 は、分極のしみ出しが起きている力もである。この分極反転あるいは分極変化によつ て、上部電極 18とその近傍の双極子の正極側とで局所的な集中電界が発生するこ とにより、上部電極 18から 1次電子が引き出され、上部電極 18から引き出された前記 1次電子がェミッタ部 22に衝突して、該ェミッタ部 22から 2次電子が放出される。 [0085] Then, when a drive pulse Pd having a predetermined level of amplitude is applied between the upper electrode 18 and the lower electrode 20, at least a part of the emitter section 22 is polarized or reversed or polarized as shown in FIG. Changed. Here, the part where polarization inversion or polarization change is Not only the portion directly below the electrode 18 but also the upper electrode 18 is not directly above, and the portion where the surface is exposed is similarly subjected to polarization inversion or polarization change in the vicinity of the upper electrode 18. . That is, the portion where the surface of the emitter 22 is exposed in the vicinity of the upper electrode 18 is also the force that causes the seepage of polarization. As a result of this polarization reversal or polarization change, a local concentrated electric field is generated between the upper electrode 18 and the positive electrode side of the nearby dipole, whereby primary electrons are extracted from the upper electrode 18 and the upper electrode 18 The primary electrons extracted from 18 collide with the emitter section 22, and secondary electrons are emitted from the emitter section 22.
[0086] この実施の形態のように、上部電極 18、ェミッタ部 22及び真空の 3重点 Aを有する 場合には、上部電極 18のうち、 3重点 Aの近傍部分から 1次電子が引き出され、この 3重点 Aから引き出された 1次電子がェミッタ部 22に衝突して、該ェミッタ部 22から 2 次電子が放出される。なお、上部電極 18の厚みが極薄（一 lOnm)である場合には、 該上部電極 18とェミッタ部 22との界面力も電子が放出されることになる。  [0086] When the upper electrode 18, the emitter 22 and the vacuum triple point A are provided as in this embodiment, primary electrons are extracted from the vicinity of the triple point A in the upper electrode 18, The primary electrons extracted from the triple point A collide with the emitter section 22, and secondary electrons are emitted from the emitter section 22. When the thickness of the upper electrode 18 is extremely thin (1 lOnm), electrons are also emitted from the interface force between the upper electrode 18 and the emitter 22.
[0087] ここで、所定レベルの振幅を有する駆動パルス Pdが印加されることによる作用を更 に詳細に説明する。  [0087] Here, the effect of applying the drive pulse Pd having a predetermined level of amplitude will be described in more detail.
[0088] 先ず、上部電極 18と下部電極 20間に所定レベルの振幅を有する駆動パルス Pdが 印加されることによって、上述したように、ェミッタ部 22から 2次電子が放出されること になる。即ち、分極が反転あるいは変化されたェミッタ部 22のうち、上部電極 18の近 傍に帯電する双極子が放出電子を引き出すこととなる。  First, when a drive pulse Pd having a predetermined level of amplitude is applied between the upper electrode 18 and the lower electrode 20, secondary electrons are emitted from the emitter section 22 as described above. That is, in the emitter section 22 whose polarization has been reversed or changed, a dipole charged near the upper electrode 18 draws out the emitted electrons.
[0089] つまり、上部電極 18のうち、ェミッタ部 22との界面近傍において局所的な力ソード が形成され、ェミッタ部 22のうち、上部電極 18の近傍の部分に帯電している双極子 の +極が局所的なアノードとなって上部電極 18から電子が引き出され、その引き出 された電子のうち、一部の電子がコレクタ電極 32 (図 1参照）に導かれて蛍光体 34を 励起し、外部に蛍光体発光として具現されることになる。また、前記引き出された電子 のうち、一部の電子がェミッタ部 22に衝突して、ェミッタ部 22から 2次電子が放出さ れ、該 2次電子がコレクタ電極 32に導かれて蛍光体 34を励起することになる。  That is, a local force sword is formed in the vicinity of the interface with the emitter portion 22 in the upper electrode 18, and + of the dipole that is charged in a portion in the vicinity of the upper electrode 18 in the emitter portion 22. The pole becomes a local anode and electrons are extracted from the upper electrode 18, and some of the extracted electrons are guided to the collector electrode 32 (see FIG. 1) to excite the phosphor 34. It will be embodied as phosphor light emission outside. Of the extracted electrons, some of the electrons collide with the emitter section 22, secondary electrons are emitted from the emitter section 22, and the secondary electrons are guided to the collector electrode 32 to be phosphor 34. Will be excited.
[0090] ここで、 2次電子の放出分布について図 8を参照しながら説明する。図 8に示すよう に、 2次電子は、ほとんどエネルギーがゼロに近いものが大多数であり、ェミッタ部 22 の表面力 真空中に放出されると、周囲の電界分布のみに従って運動することにな る。つまり、 2次電子は、初速がほとんど O (mZsec)の状態力も周囲の電界分布に従 つて加速される。このため、図 1に示すように、ェミッタ部 22とコレクタ電極 32間に電 界 Eaが発生しているとすると、 2次電子は、この電界 Eaに沿って、その放出軌道が決 定される。つまり、直進性の高い電子源を実現させることができる。このような初速の 小さい 2次電子は、 1次電子のクーロン衝突でエネルギーを得て、ェミッタ部 22の外 へ飛び出した固体内電子である。 Here, the secondary electron emission distribution will be described with reference to FIG. As shown in Fig. 8, the majority of secondary electrons have almost zero energy, and when they are released into the surface force of the emitter 22 in a vacuum, they move only according to the surrounding electric field distribution. The In other words, the secondary electrons are accelerated according to the surrounding electric field distribution, with the initial force being almost O (mZsec). Therefore, as shown in FIG. 1, if an electric field Ea is generated between the emitter 22 and the collector electrode 32, the secondary electrons have their emission trajectory determined along the electric field Ea. . That is, an electron source with high straightness can be realized. Such secondary electrons with a small initial velocity are electrons in the solid that have jumped out of the emitter 22 by obtaining energy from the Coulomb collision of the primary electrons.
[0091] ところで、図 8からもわかるように、 1次電子のエネルギー Eに相当するエネルギー By the way, as can be seen from FIG. 8, the energy corresponding to the energy E of the primary electrons
0  0
をもった 2次電子が放出されている。この 2次電子は、上部電極 18から放出された 1 次電子がェミッタ部 22の表面近くで散乱したもの（反射電子)である。そして、本明細 書内で述べて 、る 2次電子は、前記反射電子ゃォージェ電子も含んで定義するもの とする。  Secondary electrons are emitted. The secondary electrons are those in which the primary electrons emitted from the upper electrode 18 are scattered near the surface of the emitter section 22 (reflected electrons). As described in this specification, the secondary electrons are defined to include the reflected electron cathode electrons.
[0092] 上部電極 18の厚みが極薄（一 lOnm)である場合、上部電極 18から放出された 1 次電子は、上部電極 18とェミッタ部 22の界面で反射してコレクタ電極 32に向力 こと になる。  [0092] When the thickness of the upper electrode 18 is extremely thin (one lOnm), the primary electrons emitted from the upper electrode 18 are reflected at the interface between the upper electrode 18 and the emitter 22 and directed to the collector electrode 32. It will be.
[0093] ここで、図 6に示すように、電界集中ポイント Aでの電界の強さ Eは、局所的なァノ  [0093] Here, as shown in Fig. 6, the electric field strength E at the electric field concentration point A is expressed as a local anomaly.
A  A
ードと局所的な力ソード間の電位差を V (la, lk)、局所的なアノードと局所的なカソー ド間の距離を dとしたとき、 E =V(la, lk) /dの関係がある。この場合、局所的なァ  E = V (la, lk) / d, where V (la, lk) is the potential difference between the power and local force swords, and d is the distance between the local anode and the local cathode. There is. In this case, the local key
A A A  A A A
ノードと局所的な力ソード間の距離 d  Distance d between node and local force sword
Aは非常に小さいことから、電子放出に必要な電 界の強さ Eを容易に得ることができる（電界の強さ Eが大きくなつていることを図 6上  Since A is very small, the electric field strength E required for electron emission can be easily obtained (the electric field strength E increases as shown in Fig. 6).
A A  A A
では実線矢印によって示している）。これは、電圧 Vakの低電圧化につながる。  (Indicated by solid arrows). This leads to lower voltage Vak.
[0094] そして、上部電極 18からの電子放出がそのまま進行すれば、ジュール熱によって 蒸散して浮遊するェミッタ部 22の構成原子が前記放出された電子によって正イオン と電子に電離され、この電離によって発生した電子が更にェミッタ部 22の構成原子 等を電離するため、指数関数的に電子が増え、これが進行して電子と正イオンが中 性的に存在すると局所プラズマとなる。なお、 2次電子も前記電離を促進させることが 考えられる。前記電離によって発生した正イオンが例えば上部電極 18に衝突するこ とによって、上部電極 18が損傷することも考えられる。 [0094] Then, if the electron emission from the upper electrode 18 proceeds as it is, the constituent atoms of the emitter section 22 that are evaporated and floated by Joule heat are ionized into positive ions and electrons by the emitted electrons. The generated electrons further ionize the constituent atoms of the emitter section 22 and the like, so that the number of electrons increases exponentially, and when this proceeds and the electrons and positive ions are neutral, local plasma is generated. Secondary electrons may also promote the ionization. It is conceivable that the positive electrode generated by the ionization collides with, for example, the upper electrode 18 to damage the upper electrode 18.
[0095] しかし、この電子放出素子 12Aでは、図 7に示すように、上部電極 18から引き出さ れた電子が、局所アノードとして存在するェミッタ部 22の双極子の +極に引かれ、上 部電極 18の近傍におけるェミッタ部 22の表面の負極性への帯電が進行することに なる。その結果、電子の加速因子 (局所的な電位差)が緩和され、 2次電子放出に至 るポテンシャルが存在しなくなり、ェミッタ部 22の表面における負極性の帯電が更に 進行することになる。 However, in this electron-emitting device 12A, as shown in FIG. Thus, the electrons are attracted to the + pole of the dipole of the emitter portion 22 existing as a local anode, and the surface of the emitter portion 22 in the vicinity of the upper electrode 18 is charged to the negative polarity. As a result, the electron acceleration factor (local potential difference) is relaxed, the potential leading to the secondary electron emission does not exist, and the negative charge on the surface of the emitter portion 22 further proceeds.
[0096] そのため、双極子における局所的なアノードの正極性が弱められ、局所的なァノー ドと局所的な力ソード間の電界の強さ Eが小さくなり（電界の強さ Eが小さくなつてい  [0096] Therefore, the local positive polarity of the anode in the dipole is weakened, and the electric field strength E between the local anode and the local force sword is reduced (the electric field strength E is reduced).
A A  A A
ることを図 7上では破線矢印によって示している）、電子放出は停止することになる。  This is indicated by broken arrows in FIG. 7), and the electron emission is stopped.
[0097] 即ち、図 9Aに示すように、上部電極 18と下部電極 20間に印加される駆動電圧 Va として、電圧 Valを例えば + 100V、電圧 Va2を例えば- 100Vとしたとき、電子放出 が行われたピーク時点 P1における上部電極 18と下部電極 20間の電圧変化 AVak は、 20V以内（図 9Bの例では 10V程度）であってほとんど変化がない。そのため、正 イオンの発生はほとんどなぐ正イオンによる上部電極 18の損傷を防止することがで き、電子放出素子 12Aの長寿命化において有利となる。 That is, as shown in FIG. 9A, when the driving voltage Va applied between the upper electrode 18 and the lower electrode 20 is set to a voltage Val of, for example, +100 V and a voltage Va2 of, for example, −100 V, electron emission is performed. The voltage change AVak between the upper electrode 18 and the lower electrode 20 at the broken peak point P1 is within 20V (about 10V in the example of FIG. 9B) and hardly changes. Therefore, generation of positive ions can prevent damage to the upper electrode 18 due to positive ions, which is advantageous in extending the life of the electron-emitting device 12A.
[0098] ここで、ェミッタ部 22の絶縁破壊電圧として、少なくとも lOkVZmmを有しているこ とが好ましい。この例では、ェミッタ部 22の厚さ dを例えば 20 mとしたとき、上部電 極 18と下部電極 20間に- 100Vの駆動電圧を印加しても、ェミッタ部 22が絶縁破壊 に至ることはない。 Here, it is preferable that the dielectric breakdown voltage of the emitter portion 22 has at least lOkVZmm. In this example, when the thickness d of the emitter 22 is set to 20 m, for example, even if a drive voltage of −100 V is applied between the upper electrode 18 and the lower electrode 20, the emitter 22 will not break down. Absent.
[0099] ところで、ェミッタ部 22から放出された電子が再びェミッタ部 22に衝突したり、ェミツ タ部 22の表面近傍での電離等によって、該ヱミッタ部 22が損傷を受け、結晶欠陥が 誘発し、構造的にも脆くなるおそれがある。  By the way, the electrons emitted from the emitter part 22 collide with the emitter part 22 again, or ionization near the surface of the emitter part 22 is damaged, so that the crystal part 22 is damaged and crystal defects are induced. There is also a risk that the structure becomes brittle.
[0100] そこで、ェミッタ部 22を、真空中での蒸発温度が大きい誘電体で構成することが好 ましぐ例えば Pbを含まない BaTiO等にて構成するようにしてもよい。これにより、ェ  [0100] Therefore, it is preferable that the emitter 22 is made of a dielectric having a high evaporation temperature in vacuum. For example, the emitter 22 may be made of BaTiO or the like not containing Pb. This
3  Three
ミッタ部 22の構成原子がジュール熱によって蒸散しに《なり、電子による電離の促 進を妨げることができる。これは、ェミッタ部 22の表面を保護する上で有効となる。  The constituent atoms of the mitter section 22 are evaporated by Joule heat, which can hinder the promotion of ionization by electrons. This is effective in protecting the surface of the emitter portion 22.
[0101] また、コレクタ電極 32のパターン形状や電位を適宜変更したり、ェミッタ部 22とコレ クタ電極 32との間に図示しない制御電極等を配置することによって、ェミッタ部 22と コレクタ電極 32間の電界分布を任意に設定することにより、 2次電子の放出軌道を制 御し易くなり、電子ビーム径の収束、拡大、変形も容易になる。 [0101] Further, the pattern shape and potential of the collector electrode 32 are appropriately changed, or a control electrode (not shown) is disposed between the emitter portion 22 and the collector electrode 32, whereby the emitter electrode 22 and the collector electrode 32 are arranged. The secondary electron emission trajectory is controlled by arbitrarily setting the electric field distribution of It becomes easy to control, and the convergence, expansion and deformation of the electron beam diameter are also facilitated.
[0102] このように、電子放出素子 12Aにおいては、ェミッタ部 22から放出される 2次電子を 出力としたので、電子放出素子 12Aを用いた光源 10Aの長寿命化及び信頼性の向 上を図ることができる。し力も、この第 1の実施の形態では、複数の電子放出素子 12 Aを二次元的に配列するようにしたので、長寿命化及び信頼性の向上を図ることがで きる面光源が実現されることになる。  [0102] As described above, in the electron-emitting device 12A, since the secondary electrons emitted from the emitter 22 are used as an output, the life of the light source 10A using the electron-emitting device 12A is extended and the reliability is improved. Can be planned. However, in the first embodiment, since the plurality of electron-emitting devices 12A are arranged two-dimensionally, a surface light source capable of extending the life and improving the reliability is realized. Will be.
[0103] ここで、面光源の利点をディスプレイとの差異で説明すると、面光源は、ディスプレ ィと異なり、常に全面発光でよいため、例えば行走査等の複雑な駆動を行う必要がな ぐ一括のスタティック駆動でよい。また、電子放出による発光スポット径の制御が不 要になることから、電子放出素子と蛍光体間に例えばフォーカスレンズとしての機能 を果たす制御電極等を設置する必要がない。これは、機械的構成並びに回路構成 の簡略ィ匕につながる。  [0103] Here, the advantages of the surface light source will be described in terms of the difference from the display. The surface light source may always emit the entire surface, unlike the display, so that it is not necessary to perform complicated driving such as row scanning. Static drive is sufficient. Further, since it is not necessary to control the diameter of the light emission spot by electron emission, there is no need to install a control electrode or the like that functions as a focus lens, for example, between the electron-emitting device and the phosphor. This leads to simplification of the mechanical configuration as well as the circuit configuration.
[0104] ディスプレイは、画像信号に応じて高速に変化するデータ信号を扱う必要がある。  [0104] The display needs to handle a data signal that changes at high speed according to the image signal.
従って、駆動電圧は、階調に応じて変調された複雑な波形となる。一方、面光源は、 画像信号に応じて高速に変化するデータ信号を扱う必要がないため、駆動電圧とし て単純な波形 (パルス周期やパルス幅がそれぞれ一定とされた波形)を用いることが できる。その結果、面光源に後述する電力回収回路を接続する場合に、該電力回収 回路の回路定数、回路切り換えタイミング等を高精度に設定できるだけでなぐ駆動 電圧のほぼ 100%を電力回収させることも可能となる。  Therefore, the drive voltage has a complex waveform modulated according to the gradation. On the other hand, a surface light source does not need to handle a data signal that changes at a high speed in accordance with an image signal, so a simple waveform (a waveform with a constant pulse period and pulse width) can be used as a drive voltage. . As a result, when a power recovery circuit (described later) is connected to the surface light source, it is possible to recover almost 100% of the drive voltage as long as the circuit constants and circuit switching timing of the power recovery circuit can be set with high accuracy. It becomes.
[0105] 上述の例では、透明板 30の裏面にコレクタ電極 32を形成し、該コレクタ電極 32の 表面（上部電極 18と対向する面）に蛍光体 34を形成するようにした力 その他、図 1 0に示す第 1の変形例に係る光源 lOAaのように、透明板 30の裏面に蛍光体 34を形 成し、該蛍光体 34を覆うようにコレクタ電極 32を形成するようにしてもよい。この場合 、コレクタ電極 32がメタルバックとして機能する。ェミッタ部 22から放出された 2次電 子はコレクタ電極 32を貫通して蛍光体 34に進入し、該蛍光体 34を励起する。従って 、コレクタ電極 32は 2次電子が貫通できる程度の厚さであり、 lOOnm以下が好ましい 。 2次電子の運動エネルギーが大きいほど、コレクタ電極 32の厚みを厚くすることが できる。 [0106] このような構成とすることで以下の効果を奏することができる。 [0105] In the above-described example, the force that the collector electrode 32 is formed on the back surface of the transparent plate 30, and the phosphor 34 is formed on the surface of the collector electrode 32 (the surface facing the upper electrode 18). As in the light source lOAa according to the first modification shown in 10, the phosphor 34 may be formed on the back surface of the transparent plate 30, and the collector electrode 32 may be formed so as to cover the phosphor 34. . In this case, the collector electrode 32 functions as a metal back. The secondary electrons emitted from the emitter 22 penetrate the collector electrode 32 and enter the phosphor 34 to excite the phosphor 34. Accordingly, the collector electrode 32 is thick enough to allow secondary electrons to pass through, and is preferably 100 nm or less. As the kinetic energy of the secondary electrons increases, the collector electrode 32 can be made thicker. [0106] With such a configuration, the following effects can be obtained.
[0107] (1)蛍光体 34が導電性でない場合、蛍光体 34の帯電 (負）を防ぎ、 2次電子の加速 電界を維持することができる。  (1) When the phosphor 34 is not conductive, charging (negative) of the phosphor 34 can be prevented, and the accelerating electric field of secondary electrons can be maintained.
[0108] (2)コレクタ電極 32が蛍光体 34の発光を反射して、蛍光体 34の発光を効率よく透明 板 30側 (発光面側）に放出することができる。  (2) The collector electrode 32 reflects the light emitted from the phosphor 34, and the light emitted from the phosphor 34 can be efficiently emitted to the transparent plate 30 side (light emitting surface side).
[0109] (3)蛍光体 34への過度な 2次電子の衝突を防ぐことができ、蛍光体 34の劣化や蛍光 体 34からのガス発生を防止することができる。  (3) Excessive secondary electron collision with the phosphor 34 can be prevented, and deterioration of the phosphor 34 and generation of gas from the phosphor 34 can be prevented.
[0110] また、他の変形例としては、図 11の第 2の変形例に係る光源 lOAbのように、透明 板 30に蛍光体 34を形成し、複数の電子放出素子 12Aを有する発光部 14Aと蛍光 体 34間の雰囲気中に、例えば水銀粒子 40等を封入して構成するようにしてもょ 、。 この場合、電子放出素子 12Aから放出された 2次電子のうち、一部の電子が水銀粒 子 40に衝突し、水銀粒子 40が励起状態になって紫外線 42を発する。この紫外線 42 力 周辺の蛍光体 34に当たることによって、蛍光体 34が励起して外部に蛍光体発光 として具現される。  [0110] As another modified example, as in the light source lOAb according to the second modified example of FIG. 11, a phosphor 34 is formed on the transparent plate 30, and the light emitting unit 14A having a plurality of electron-emitting devices 12A is formed. For example, mercury particles 40 may be enclosed in the atmosphere between the phosphor 34 and the phosphor 34. In this case, some of the secondary electrons emitted from the electron-emitting device 12A collide with the mercury particles 40, and the mercury particles 40 are excited to emit ultraviolet rays 42. By hitting the phosphor 34 in the vicinity of this ultraviolet ray 42 force, the phosphor 34 is excited and embodied as phosphor emission to the outside.
[0111] そして、駆動回路 16Aは、図 12に示すように、タイミング発生回路 44と駆動電圧生 成回路 46とを有する。  The drive circuit 16A includes a timing generation circuit 44 and a drive voltage generation circuit 46, as shown in FIG.
[0112] タイミング発生回路 44は、点灯 Z消灯を示す制御信号 Scとクロック Pcに基づいて、 駆動パルス Pdの出力タイミングを規定するためのタイミングパルス Ptを生成し、出力 する。具体的には、前記タイミング発生回路 44は、例えば図 13Aに示すように、制御 信号 Scが高レベル（点灯を示すレベル）となった時点からクロック Pc (図 13B参照）の 計数を開始し、図 13Cに示すように、 mクロックに相当する期間 T2において高レベル 、 nクロックに相当する期間 T1にお!/、て低レベルのタイミングパルス Ptを繰り返し生 成し、出力する。このタイミングパルス Ptは、制御信号 Scが点灯を示す期間（点灯期 間 Ts)においてのみ連続して出力される。制御信号 Scが低レベル (消灯を示すレべ ル)の期間、すなわち、消灯期間 Tnにおいては、前記タイミング発生回路 44からは 低レベルの信号のみが出力されることになる。  [0112] The timing generation circuit 44 generates and outputs a timing pulse Pt for defining the output timing of the drive pulse Pd based on the control signal Sc indicating the lighting Z extinction and the clock Pc. Specifically, for example, as shown in FIG. 13A, the timing generation circuit 44 starts counting the clock Pc (see FIG. 13B) from the time when the control signal Sc becomes high level (level indicating lighting), As shown in FIG. 13C, a high-level timing pulse Pt is repeatedly generated and output during a period T2 corresponding to m clocks and during a period T1 corresponding to n clocks. This timing pulse Pt is continuously output only during the period when the control signal Sc is turned on (lighting period Ts). In the period during which the control signal Sc is at a low level (level indicating turn-off), that is, the turn-off period Tn, only the low-level signal is output from the timing generation circuit 44.
[0113] 駆動電圧生成回路 46は、前記タイミング発生回路 44からのタイミングパルス Ptに 基づいて、各電子放出素子 12Aの上部電極 18と下部電極 20間に印加すべき駆動 電圧 Vaを生成し、出力する。具体的には、この駆動電圧生成回路 46は、図 13Dに 示すように、タイミング発生回路 44の出力が低レベルの期間 T1に電圧 Valを出力し 、タイミング発生回路 44の出力が高レベルの期間 T2に電圧 Va2を出力する。すなわ ち、駆動電圧生成回路 46から出力される駆動電圧 Vaは、タイミング発生回路 44のタ イミングパルス Ptに同期して駆動パルス Pdが連続して現れる波形を有する。 [0113] The drive voltage generation circuit 46 is a drive to be applied between the upper electrode 18 and the lower electrode 20 of each electron-emitting device 12A based on the timing pulse Pt from the timing generation circuit 44. Generate and output voltage Va. Specifically, as shown in FIG. 13D, the drive voltage generation circuit 46 outputs the voltage Val during the period T1 when the output of the timing generation circuit 44 is at a low level, and outputs the voltage Val during the period when the output of the timing generation circuit 44 is at a high level. Output voltage Va2 to T2. That is, the drive voltage Va output from the drive voltage generation circuit 46 has a waveform in which the drive pulse Pd appears continuously in synchronization with the timing pulse Pt of the timing generation circuit 44.
[0114] 従って、点灯期間 Tsにおいては、各電子放出素子 12Aの上部電極 18と下部電極 20間への駆動パルス Pdの印加に伴って連続的に電子が放出され、蛍光体 34を励 起する。その結果、点灯期間 Tsにおいて、蛍光体発光が持続されることになる。なお 、消灯期間 Tnにおいては、各電子放出素子 12Aの上部電極 18と下部電極 20間へ の駆動パルス Pdの印加が行われないため、電子放出素子 12A力 の電子放出は停 止されており、次の点灯指示まで消灯が持続されることになる。  Accordingly, in the lighting period Ts, electrons are continuously emitted with the application of the drive pulse Pd between the upper electrode 18 and the lower electrode 20 of each electron-emitting device 12A, and the phosphor 34 is excited. . As a result, phosphor emission is sustained during the lighting period Ts. In addition, during the extinction period Tn, since the driving pulse Pd is not applied between the upper electrode 18 and the lower electrode 20 of each electron-emitting device 12A, the electron emission of the electron-emitting device 12A force is stopped. The extinction is continued until the next lighting instruction.
[0115] 次に、駆動回路 16Aの好ましい実施の形態について図 14及び図 15を参照しなが ら説明する。この実施の形態に係る駆動回路 16Aは、図 14に示すように、上述した タイミング発生回路 44と、駆動電圧生成回路 46に加えて電力回収回路 50が接続さ れている。この図 14では、発光部 14Aに配列された全ての電子放出素子 12Aを代 表的に 1つのコンデンサ Cとして示す。従って、コンデンサ Cの一方の電極は、全ての 電子放出素子 12Aの上部電極 18を指し、コンデンサ Cの他方の電極は、全ての電 子放出素子 12Aの下部電極 20を指す。  Next, a preferred embodiment of the drive circuit 16A will be described with reference to FIG. 14 and FIG. In the drive circuit 16A according to this embodiment, as shown in FIG. 14, a power recovery circuit 50 is connected in addition to the timing generation circuit 44 and the drive voltage generation circuit 46 described above. In FIG. 14, all the electron-emitting devices 12A arranged in the light emitting portion 14A are representatively shown as one capacitor C. Therefore, one electrode of the capacitor C indicates the upper electrode 18 of all the electron-emitting devices 12A, and the other electrode of the capacitor C indicates the lower electrode 20 of all the electron-emitting devices 12A.
[0116] 電力回収回路 50の概念的な構成を説明すると、コンデンサ Cの両電極 (上部電極 18と下部電極 20)間にバッファコンデンサ Cfと第 1の直列回路 52がそれぞれ並列に 接続され、更に、コンデンサ Cとバッファコンデンサ Cfとの間に、第 2の直列回路 54が 接続されている。  [0116] The conceptual configuration of the power recovery circuit 50 will be described. A buffer capacitor Cf and a first series circuit 52 are connected in parallel between both electrodes (upper electrode 18 and lower electrode 20) of the capacitor C, respectively. The second series circuit 54 is connected between the capacitor C and the buffer capacitor Cf.
[0117] 図 14の例では、 1つのコンデンサ Cに対して 1つのバッファコンデンサ Cfが接続さ れた形態をとっている力 これに限らず、 1つのコンデンサ Cに対して 2以上のバッフ ァコンデンサ Cfを接続してもよぐノ ッファコンデンサ Cfの個数は任意である。  [0117] In the example of FIG. 14, the force is such that one buffer capacitor Cf is connected to one capacitor C. Not limited to this, two or more buffer capacitors are used for one capacitor C. The number of Cf capacitors that can be connected to Cf is arbitrary.
[0118] 第 1の直列回路 52は、第 1のスイッチング回路 SW1と電流抑制用の抵抗 rと正電源 56 (電圧 Val)とが直列に接続されて構成され、第 2の直列回路 54は、第 2のスイツ チング回路 SW2とインダクタ 58 (インダクタンス L)とが直列に接続されて構成されて いる。 [0118] The first series circuit 52 is configured by connecting a first switching circuit SW1, a current suppression resistor r, and a positive power source 56 (voltage Val) in series. The second switching circuit SW2 and inductor 58 (inductance L) are connected in series. Yes.
[0119] そして、駆動電圧生成回路 46は、タイミング発生回路 44からのタイミングノルス Pt に基づいて、第 1及び第 2のスイッチング回路 SW1及び SW2を制御するための制御 信号 Scl及び Sc2を生成し、出力する。  Then, the drive voltage generation circuit 46 generates control signals Scl and Sc2 for controlling the first and second switching circuits SW1 and SW2 based on the timing norse Pt from the timing generation circuit 44, and Output.
[0120] ここで、本実施の形態に係る駆動回路 16Aの動作を図 15の波形図も参照しながら 説明する。  [0120] Here, the operation of the drive circuit 16A according to the present embodiment will be described with reference to the waveform diagram of FIG.
[0121] 先ず、点灯期間 Tsの開始前においては、予め第 1のスイッチング回路 SW1が ON 、第 2のスイッチング回路 SW2が OFFとされており、コンデンサ Cの両端電圧は正電 源 56の電圧 Valとほぼ同じ電圧となっている。  [0121] First, before the lighting period Ts starts, the first switching circuit SW1 is turned on in advance and the second switching circuit SW2 is turned off in advance, and the voltage across the capacitor C is equal to the voltage Val of the positive power supply 56. Is almost the same voltage.
[0122] そして、点灯期間 Tsに入った後における期間 T2の開始時点 tlにおいて、駆動電 圧生成回路 46の制御によって第 1のスイッチング回路 SW1が OFFとされ、第 2のス イッチング回路 SW2が ONとされる。これによつて、インダクタ 58とコンデンサ Cとの正 弦波振動が開始され、コンデンサ Cにおける両端電圧の共振的な減衰が開始する。 このとき、コンデンサ Cに蓄積されて!、た電荷がバッファコンデンサ Cfに回収されるこ とになる。  [0122] Then, at the start time tl of the period T2 after entering the lighting period Ts, the first switching circuit SW1 is turned off and the second switching circuit SW2 is turned on by the control of the drive voltage generation circuit 46. It is said. As a result, the sine wave oscillation of the inductor 58 and the capacitor C is started, and the resonant attenuation of the voltage across the capacitor C is started. At this time, the charge accumulated in the capacitor C is collected by the buffer capacitor Cf.
[0123] 次の時点 t2、すなわち、コンデンサ Cの振動波形 (電圧波形）が最も低レベル (電圧 ： -Val =Va2)となった時点において、駆動電圧生成回路 46の制御によって第 2の スイッチング回路 SW2が OFFとされ、コンデンサ Cとバッファコンデンサ Cfの系は高 インピーダンス状態となる。従って、この時点 t2以降、期間 T2の終了時点 t3まで電 圧 Va2が維持される。特に、上述したように、電圧 Valから電圧 Va2に低下する時点 で、各電子放出素子 12Aのェミッタ部 22から 2次電子の放出が行われ、この電子放 出によって透明板 30の全面を通じて発光が行われる。  [0123] At the next time t2, that is, when the vibration waveform (voltage waveform) of the capacitor C becomes the lowest level (voltage: -Val = Va2), the second switching circuit is controlled by the drive voltage generation circuit 46. SW2 is turned off, and the system of capacitor C and buffer capacitor Cf enters a high impedance state. Therefore, after this time t2, the voltage Va2 is maintained until the end time t3 of the period T2. In particular, as described above, when the voltage Val drops to the voltage Va2, secondary electrons are emitted from the emitter section 22 of each electron-emitting device 12A, and light is emitted through the entire surface of the transparent plate 30 by this electron emission. Done.
[0124] その後、期間 T2の終了時点 t3において、駆動電圧生成回路 46の制御によって第 2のスイッチング回路 SW2が ONとされる。これによつて、インダクタ 62とコンデンサ C との正弦波振動が開始され、コンデンサ Cにおける両端電圧の共振的な増幅が開始 する。このとき、バッファコンデンサ Cfに蓄積されていた電荷がコンデンサ Cに充電さ れる。  [0124] Thereafter, at the end time t3 of the period T2, the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46. As a result, sinusoidal oscillation between the inductor 62 and the capacitor C is started, and resonance amplification of the voltage across the capacitor C is started. At this time, the charge accumulated in the buffer capacitor Cf is charged into the capacitor C.
[0125] 次の時点 t4、すなわち、コンデンサ Cの振動波形 (電圧波形）が最も高レベル (電圧 ： Val)となった時点において、駆動電圧生成回路 46の制御によって第 2のスィッチ ング回路 SW2が OFFとされ、第 1のスイッチング回路 SW1が ONとされる。この時点 t 4以降、次の期間 T2の開始時点 t2まで電圧 Valが維持される。 [0125] Next time t4, that is, the vibration waveform (voltage waveform) of capacitor C is the highest level (voltage :), the second switching circuit SW2 is turned off and the first switching circuit SW1 is turned on by the control of the drive voltage generation circuit 46. After this time t4, the voltage Val is maintained until the start time t2 of the next period T2.
[0126] 図 13A—図 13Dに示すように、期間 T2と期間 T1の連続期間を 1ステップとしたとき 、この 1ステップが点灯期間 Tsにおいて繰り返される。そのため、電子放出素子 12A において電子放出の自己停止がなされても、再び期間 T2が到来して電子放出が行 われることから、見かけ上、点灯期間 Tsにわたつて透明板 30の全面を通じての発光 が維持された状態となる。つまり、 1回の電子放出による発光が消光する前に次の電 子放出が行われ、これにより、連続発光が行われることになる。  As shown in FIGS. 13A to 13D, when the continuous period of the period T2 and the period T1 is one step, this one step is repeated in the lighting period Ts. Therefore, even if the electron emission is stopped in the electron emission element 12A, the period T2 arrives again and the electron emission is performed, so that it is apparent that light emission through the entire surface of the transparent plate 30 occurs during the lighting period Ts. It will be maintained. In other words, the next electron emission is performed before the light emission due to one electron emission is quenched, and as a result, continuous light emission is performed.
[0127] なお、消灯期間 Tnに入った場合は、図 13A—図 13Dに示すように、各電子放出 素子 12Aに電圧 Valが印加されつづけることから、各電子放出素子 12Aから電子放 出は行われず、従って、消灯期間 Tnにわたつて消光状態が維持されることになる。  [0127] Note that when the extinguishing period Tn is entered, the voltage Val continues to be applied to each electron-emitting device 12A as shown in FIGS. 13A to 13D, so that the electron emission from each electron-emitting device 12A is performed. Therefore, the extinction state is maintained over the extinction period Tn.
[0128] このように、駆動回路 16Aに電力回収回路 50を接続することにより、駆動電圧 Va のほぼ 100%を電力回収することが可能となり、消費電力の低減において有利となる 。この例では、第 1の直列回路 52を設けて、コンデンサ Cの両端電圧を所定のタイミ ングで電圧 Valに強制的に振らせるようにしたので、インダクタ 58での電力消費に伴 う駆動電圧の減衰を回避することができる。もちろん、この光源 10Aの使用開始時点 においてコンデンサ Cの両端電圧を電圧 Valにしておき、その後、第 2のスィッチン グ回路 SW2での ONZOFF動作のみで、コンデンサ Cでの充放電とバッファコンデ ンサ Cfでの充放電を交互に行わせるようにしてもょ 、。  Thus, by connecting the power recovery circuit 50 to the drive circuit 16A, it is possible to recover almost 100% of the drive voltage Va, which is advantageous in reducing power consumption. In this example, the first series circuit 52 is provided, and the voltage across the capacitor C is forcibly swung to the voltage Val at a predetermined timing, so that the drive voltage associated with the power consumption by the inductor 58 is reduced. Attenuation can be avoided. Of course, at the start of use of this light source 10A, the voltage across the capacitor C is set to the voltage Val, and after that, only the ONZOFF operation in the second switching circuit SW2, the charge / discharge in the capacitor C and the buffer capacitor Cf Let's charge and discharge the battery alternately.
[0129] ところで、上述した第 1の実施の形態に係る光源 10Aは、全ての電子放出素子 12 Aの上部電極 18と下部電極 20間に駆動電圧 Vaを印加することによって、発光部 14 A力も透明板 30の全面を通じて発光させるようにした力 その他、図 16に示す第 3の 変形例に係る光源 lOAcのように、発光部 14Aを 2つのグループ（第 1及び第 2のグ ループ G1及び G2)に分け、第 1のグループ G1に含まれる電子放出素子 12Aの発 光時に、第 2のグループ G2に含まれる電子放出素子 12Aにおいて第 1のグループ G1に含まれる電子放出素子 12Aの電力を回収し、第 2のグループ G2に含まれる電 子放出素子 12Aの発光時に、第 1のグループ G1に含まれる電子放出素子 12Aにお いて第 2のグループ G2に含まれる電子放出素子 12Aの電力を回収するようにしても よい。 By the way, the light source 10A according to the first embodiment described above applies the driving voltage Va between the upper electrode 18 and the lower electrode 20 of all the electron-emitting devices 12A, so that the power of the light emitting unit 14A is also increased. In addition, the light source 14A is divided into two groups (first and second groups G1 and G2) as in the light source lOAc according to the third modification shown in FIG. ), When the electron-emitting devices 12A included in the first group G1 emit light, the power of the electron-emitting devices 12A included in the first group G1 is collected in the electron-emitting devices 12A included in the second group G2. When the electron-emitting devices 12A included in the second group G2 emit light, the electron-emitting devices 12A included in the first group G1 The electric power of the electron-emitting devices 12A included in the second group G2 may be recovered.
[0130] この場合、第 1のグループ G1に含まれる電子放出素子 12Aを代表的にコンデンサ C 1と示し、第 2のグループ G2に含まれる電子放出素子 12Aを代表的にコンデンサ C 2と示したとき、駆動回路 16Aとしては、図 14において括弧書きに示すように、コンデ ンサ Cに代えてコンデンサ C1とし、ノッファコンデンサ Cfに代えてコンデンサ C2とす ればよい。  [0130] In this case, the electron-emitting device 12A included in the first group G1 is typically shown as a capacitor C1, and the electron-emitting device 12A included in the second group G2 is shown as a capacitor C2. At this time, as shown in parentheses in FIG. 14, the drive circuit 16A may be a capacitor C1 instead of the capacitor C and a capacitor C2 instead of the notfa capacitor Cf.
[0131] ここで、この駆動回路 16Aの動作を図 17の波形図を参照しながら説明する。先ず、 点灯期間 Tsの開始前においては、予め第 1のスイッチング回路 SW1が ON、第 2の スイッチング回路 SW2が OFFとされており、コンデンサ C1の両端電圧は正電源 56 の電圧 Valとほぼ同じ電圧となっている。  Now, the operation of the drive circuit 16A will be described with reference to the waveform diagram of FIG. First, before the lighting period Ts starts, the first switching circuit SW1 is turned on in advance and the second switching circuit SW2 is turned off in advance, and the voltage across the capacitor C1 is almost the same voltage as the voltage Val of the positive power supply 56. It has become.
[0132] そして、点灯期間 Tsに入った後における期間 T2の開始時点 tlにおいて、駆動電 圧生成回路 46の制御によって第 1のスイッチング回路 SW1が OFFとされ、第 2のス イッチング回路 SW2が ONとされる。これによつて、コンデンサ C1では、インダクタ 58 とコンデンサ C1との正弦波振動が開始され、コンデンサ C1における両端電圧の共 振的な減衰が開始する。このとき、コンデンサ C1に蓄積されていた電荷がコンデンサ C2に回収されることになる。  [0132] Then, at the start time tl of the period T2 after entering the lighting period Ts, the first switching circuit SW1 is turned OFF and the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46. It is said. Thereby, in the capacitor C1, the sinusoidal oscillation of the inductor 58 and the capacitor C1 is started, and the resonance attenuation of the voltage across the capacitor C1 is started. At this time, the electric charge accumulated in the capacitor C1 is recovered by the capacitor C2.
[0133] すなわち、コンデンサ C2から見れば、前記時点 tlにおいて、インダクタ 58とコンデ ンサ C2との正弦波振動が開始され、コンデンサ C2における両端電圧の共振的な増 幅が開始する。このとき、コンデンサ C1に蓄積されていた電荷がコンデンサ C2に充 電される。  That is, from the viewpoint of the capacitor C2, at the time tl, the sinusoidal oscillation of the inductor 58 and the capacitor C2 is started, and the resonance voltage of the both-end voltage in the capacitor C2 is started. At this time, the charge stored in the capacitor C1 is charged to the capacitor C2.
[0134] 次の時点 t2、すなわち、コンデンサ C1の振動波形 (電圧波形）が最も低レベル (電 圧: Val =Va2)となった時点において、駆動電圧生成回路 46の制御によって第 2 のスイッチング回路 SW2が OFFとされ、コンデンサ C1とコンデンサ C2の系は高イン ピーダンス状態となる。従って、コンデンサ C1では、この時点 t2以降、期間 T2の終 了時点 t3まで電圧 Va2が維持され、コンデンサ C2では、電圧 Valが維持される。  [0134] At the next time point t2, that is, when the vibration waveform (voltage waveform) of the capacitor C1 becomes the lowest level (voltage: Val = Va2), the second switching circuit is controlled by the control of the drive voltage generation circuit 46. SW2 is turned off, and the system of capacitor C1 and capacitor C2 is in a high impedance state. Therefore, the voltage Va2 is maintained in the capacitor C1 after this time t2 until the end time t3 of the period T2, and the voltage Val is maintained in the capacitor C2.
[0135] 特に、時点 tlから時点 t2にかけて、コンデンサ C1の両端電圧が電圧 Valから電圧 Va2に急速に低下することから、図 16に示すように、第 1のグループ G1に属する各 電子放出素子 12Aのェミッタ部 22から 2次電子の放出が行われる。この電子放出に よって、透明板 30のうち、第 1のグループ G1に対応する領域を通じて発光が行われ る。 [0135] In particular, since the voltage across the capacitor C1 rapidly decreases from the voltage Val to the voltage Va2 from the time point tl to the time point t2, as shown in Fig. 16, each of the members belonging to the first group G1 Secondary electrons are emitted from the emitter 22 of the electron emitter 12A. Due to this electron emission, light is emitted through the region of the transparent plate 30 corresponding to the first group G1.
[0136] この期間 T2は、コンデンサ C1での電子放出に関わる期間である力 コンデンサ C2 力も見た場合は、電子放出までの準備期間 T1となる。従って、期間 Tl =期間 T2とし て設定することが好ましい。  [0136] This period T2 is a preparation period T1 until electron emission when the force capacitor C2 force, which is a period related to electron emission in the capacitor C1, is also seen. Therefore, it is preferable to set the period Tl = the period T2.
[0137] その後、期間 Τ2の終了時点 t3において、駆動電圧生成回路 46の制御によって第 2のスイッチング回路 SW2が ONとされる。これによつて、インダクタ 62とコンデンサ C 1との正弦波振動が開始され、コンデンサ C1における両端電圧の共振的な増幅が開 始する。このとき、バッファコンデンサ Cfに蓄積されていた電荷がコンデンサ Cに充電 される。  Thereafter, at the end time t3 of period Τ2, the second switching circuit SW2 is turned ON by the control of the drive voltage generation circuit 46. As a result, sinusoidal oscillation between the inductor 62 and the capacitor C1 is started, and resonance amplification of the voltage across the capacitor C1 is started. At this time, the charge accumulated in the buffer capacitor Cf is charged into the capacitor C.
[0138] すなわち、コンデンサ C2から見れば、前記時点 t3において、インダクタ 58とコンデ ンサ C2との正弦波振動が開始され、コンデンサ C2における両端電圧の共振的な減 衰が開始する。このとき、コンデンサ C2に蓄積されていた電荷がコンデンサ C1に回 収されること〖こなる。  That is, from the viewpoint of the capacitor C2, the sinusoidal oscillation of the inductor 58 and the capacitor C2 is started at the time point t3, and the resonant attenuation of the voltage across the capacitor C2 is started. At this time, the charge stored in the capacitor C2 is collected by the capacitor C1.
[0139] 次の時点 t4、すなわち、コンデンサ C1の振動波形 (電圧波形）が最も高レベル (電 圧: Val)となった時点において、駆動電圧生成回路 46の制御によって第 2のスイツ チング回路 SW2が OFFとされ、第 1のスイッチング回路 SW1が ONとされる。従って 、コンデンサ C1では、この時点 t4以降、次の期間 T2の開始時点 t2まで電圧 Valが 維持され、コンデンサ C2では、電圧 Va2が維持される。  [0139] At the next time t4, that is, when the vibration waveform (voltage waveform) of the capacitor C1 reaches the highest level (voltage: Val), the second switching circuit SW2 is controlled by the drive voltage generation circuit 46. Is turned OFF, and the first switching circuit SW1 is turned ON. Therefore, the voltage Val is maintained in the capacitor C1 after this time t4 until the start time t2 of the next period T2, and the voltage Va2 is maintained in the capacitor C2.
[0140] また、時点 t3から時点 t4にかけて、コンデンサ C2の両端電圧が電圧 Valから電圧 Va2に急速に低下することから、図 16に示すように、第 2のグループ G2に属する各 電子放出素子 12Aのェミッタ部 22から 2次電子の放出が行われる。この電子放出に よって、透明板 30のうち、第 2のグループ G2に対応する領域を通じて発光が行われ る。  [0140] Further, since the voltage across the capacitor C2 rapidly decreases from the voltage Val to the voltage Va2 from the time point t3 to the time point t4, as shown in FIG. 16, each electron-emitting device 12A belonging to the second group G2 Secondary electrons are emitted from the emitter 22. Due to this electron emission, light is emitted through the region of the transparent plate 30 corresponding to the second group G2.
[0141] 時点 t3力も期間 T1となる。この期間 T1は、コンデンサ C1では次の電子放出のた めの準備期間となるが、コンデンサ C2から見た場合は、電子放出に関わる期間 T2と なる。 [0142] そして、期間 T2と期間 Tlの連続期間（1ステップ）が点灯期間 Tsにおいて繰り返さ れることで、第 1のグループ G1における各電子放出素子 12Aでの電子放出と、第 2 のグループ G2における各電子放出素子 12Aでの電子放出が交互に行われることに なる。従って、期間 T1又は期間 T2の周期を適宜設定することで、見力 4ナ上、点灯期 間 Tsにわたつて透明板 30の全面を通じての発光が維持された状態となる。もちろん 、期間 T1又は期間 T2を意図的に長く設定して、第 1のグループ G1での発光と第 2 のグループ G2での発光の区別を人間の目でも認識できるようにしてもよ!、。 [0141] Time t3 force is also in period T1. This period T1 is a preparation period for the next electron emission in the capacitor C1, but when viewed from the capacitor C2, it is a period T2 related to the electron emission. [0142] Then, by repeating a continuous period (one step) of the period T2 and the period Tl in the lighting period Ts, the electron emission in each electron-emitting device 12A in the first group G1 and the second group G2 Electron emission from each electron-emitting device 12A is performed alternately. Accordingly, by appropriately setting the period T1 or the period T2, the light emission through the entire surface of the transparent plate 30 is maintained over the lighting period Ts over the four powers. Of course, the period T1 or the period T2 may be intentionally set to be long so that the distinction between the light emission in the first group G1 and the light emission in the second group G2 can be recognized by the human eye!
[0143] このように、第 3の変形例に係る光源 lOAcにおいては、発光動作を行っているダル ープ以外のグループに含まれる電子放出素子 12A力 電力回収のための、いわゆ るバッファコンデンサ Cfとして兼用することから、別途バッファコンデンサ Cfを設置す る必要がなぐ実装面積の縮小化、消費電力の低減を有効に図ることができる。また 、第 1のグループ G1の電子放出素子 12Aと、第 2のグループ G2の電子放出素子 12 Aを、ある単位で分散させて配置することにより、常に見かけ上、均一な面発光を得る ことちでさる。  [0143] Thus, in the light source lOAc according to the third modified example, the so-called buffer capacitor for recovering the power of the electron-emitting device 12A included in the group other than the loop that performs the light-emitting operation. Since it is also used as Cf, it is possible to effectively reduce the mounting area and power consumption without the need for a separate buffer capacitor Cf. In addition, by arranging the electron-emitting devices 12A of the first group G1 and the electron-emitting devices 12A of the second group G2 to be dispersed in a certain unit, it is possible to always obtain apparently uniform surface light emission. I'll do it.
[0144] 上述の例では、各電子放出素子 12Aから一定量の電子を放出させる場合につい て説明したが、その他、図 18に示す変形例に係る駆動回路 16Aaのように、前記タイ ミング発生回路 44、駆動電圧生成回路 46に加えて変調回路 60を接続するようにし てもよい。変調回路 60は、各電子放出素子 12Aの電子放出量を、外部に設置され た調光ボリューム（図示せず)からの調光信号 Shに応じて制御する回路である。  [0144] In the above-described example, the case where a certain amount of electrons is emitted from each electron-emitting device 12A has been described. In addition, like the drive circuit 16Aa according to the modification shown in FIG. 44. In addition to the drive voltage generation circuit 46, a modulation circuit 60 may be connected. The modulation circuit 60 is a circuit that controls the amount of electron emission of each electron-emitting device 12A according to a dimming signal Sh from a dimming volume (not shown) installed outside.
[0145] 変調回路 60での変調方式としては、 4つの変調方式がある。第 1の変調方式は、図 19Aに示すように、調光信号 Shのレベル（電圧レベル等）に基づいて、図 19Bや図 1 9C〖こ示すよう〖こ、電圧 Va2のパルス幅を変調する方式である。この場合、図 19Bに 示すように、期間 T2自体を変調するようにしてもよいし、図 19Cに示すように、期間 T 2は一定で、電圧 Va2の印加期間 τ aを変調するようにしてもよい。図 19Cの変調方 式は、図 20に示すように、電圧 Va2のパルス幅と輝度とが線形関係になることを利用 したものである。例えばパルス幅を 0から約 600 secに振ることによって、輝度を 0— 約 1020 (cdZm2)にかけて変化させることができる。し力も、電圧 Va2のパルス幅を 制御すればょ 、ため、安価なデジタル制御で高精細度の階調表現を実現させること ができる。 [0145] The modulation circuit 60 has four modulation methods. As shown in FIG. 19A, the first modulation method modulates the pulse width of the voltage Va2 as shown in FIG. 19B and FIG. 19C based on the level (voltage level, etc.) of the dimming signal Sh. It is a method. In this case, the period T2 itself may be modulated as shown in FIG. 19B, or the period T2 is constant and the voltage Va2 application period τa is modulated as shown in FIG. 19C. Also good. The modulation method in FIG. 19C utilizes the fact that the pulse width of the voltage Va2 and the luminance have a linear relationship as shown in FIG. For example, by changing the pulse width from 0 to about 600 sec, the luminance can be changed from 0 to about 1020 (cdZm2). Therefore, if the pulse width of the voltage Va2 is controlled, high-definition gradation expression can be realized with inexpensive digital control. Can do.
[0146] 第 2の変調方式は、コレクタ電圧 Vcを制御する方法であり、図 21〖こ示すよう〖こ、コレ クタ電圧 Vcと輝度とが線形関係であることを利用するものである。コレクタ電圧 Vcを 4 kVから 7kVに振ることによって、輝度を 0— 600 (cd/m2)にかけて変化させること ができる。  [0146] The second modulation method is a method of controlling the collector voltage Vc, and utilizes the fact that the collector voltage Vc and the luminance are linear as shown in FIG. By changing the collector voltage Vc from 4 kV to 7 kV, the luminance can be changed from 0 to 600 (cd / m2).
[0147] 第 3の変調方式は、駆動電圧 Vaの電圧 Va2 (電圧レベル)を制御する方法であり、 図 22に示すように、電圧 Va2と輝度とが線形関係であることを利用するものである。 例えば電圧 Va2を約 118 Vから 188 Vに振ることによって、輝度を 0— 1600 (cdZm 2)にかけて変化させることができる。  [0147] The third modulation method is a method of controlling the voltage Va2 (voltage level) of the drive voltage Va, and utilizes the fact that the voltage Va2 and the luminance are in a linear relationship as shown in FIG. is there. For example, by changing the voltage Va2 from about 118 V to 188 V, the luminance can be changed from 0 to 1600 (cdZm 2).
[0148] 第 4の変調方式は、駆動電圧 Vaの電圧 Valを制御する方法であるが、図 23に示 すように、電圧 Valと輝度とが非線形関係であることから、制御が難しぐし力も、電圧 Valに対するアナログ電圧制御が必要であるため、回路の工夫が必要となる。  [0148] The fourth modulation method is a method of controlling the voltage Val of the drive voltage Va. However, as shown in Fig. 23, since the voltage Val and the luminance are in a non-linear relationship, the control is difficult and the force of the force is also low. Since the analog voltage control for the voltage Val is necessary, the circuit must be devised.
[0149] 従って、第 1一第 4の変調方式のうち、電圧 Va2のパルス幅を変調する第 1の変調 方式を採用することが好まし 、。  [0149] Therefore, it is preferable to employ the first modulation method that modulates the pulse width of the voltage Va2 among the first, first, and fourth modulation methods.
[0150] 第 1の実施の形態に係る光源 10Aは、図 1に示すように、複数の電子放出素子 12 Aに対して 1つのコレクタ電極 32を配置し、該コレクタ電極 32に抵抗 R2を介してバイ ァス電圧 Vcを印加するようにした力 その他、図 24に示す第 4の変形例の係る光源 lOAdのように、例えば光源 lOAdの列数と同じ数だけのコレクタ電極 32 (1)、 32 (2) 、 · · ·、 32 (N)を配列し、各コレクタ電極 32 (1)、 32 (2)、 · · ·、 32 (N)に対してそれ ぞれ抵抗 Rcl、 Rc2、 · · ·、 RcNを接続するようにしてもよい。この場合、製造段階で のばらつき、例えば各電子放出素子 12A毎の輝度ばらつきを、コレクタ電極 32 (1)、 32 (2)、 · · ·、 32 (N)に接続された抵抗 Rcl、 Rc2、 · · ·、 RcNを通じて調整すること ができる。  In the light source 10A according to the first embodiment, as shown in FIG. 1, one collector electrode 32 is arranged for a plurality of electron-emitting devices 12A, and the collector electrode 32 is connected via a resistor R2. For example, the same number of collector electrodes 32 (1) as the number of columns of the light source lOAd, such as the light source lOAd according to the fourth modification shown in FIG. 32 (2), ..., 32 (N) are arranged, and each collector electrode 32 (1), 32 (2), ..., 32 (N) has resistance Rcl, Rc2, ... · · · RcN may be connected. In this case, variations at the manufacturing stage, for example, luminance variations for each electron-emitting device 12A, are converted into resistances Rcl, Rc2, and 32 (N) connected to the collector electrodes 32 (1), 32 (2), ..., 32 (N). · · · · Adjustable through RcN.
[0151] 以下に、輝度ばらつきの調整について図 25—図 28を参照しながら説明する。  [0151] Hereinafter, adjustment of luminance variation will be described with reference to FIGS. 25 to 28. FIG.
[0152] 従来のばらつき低減方法は、例えば文献「電子技術 2000— 7、 p38— p41：フィー ルドエミッションディスプレイの最新技術動向」に記載されているように、ェミッタに電 流抑制用の抵抗を接続することでばらつきを低減するようにして 、る。 [0152] For example, as described in the literature "Electronic Technology 2000-7, p38- p41: Latest Technology Trends in Field Emission Display", the conventional method for reducing variation is to connect a resistor for current suppression to the emitter. By doing so, the variation is reduced.
[0153] ただ、この方法は、ェミッタに流れる電流とゲート電圧との関係となっており、輝度ば らっきを低減するための最適な抵抗値を得るまでに何度もシミュレーションを行わな ければならない。 [0153] However, this method has a relationship between the current flowing through the emitter and the gate voltage. The simulation must be repeated many times before the optimum resistance value for reducing the fluctuation is obtained.
[0154] そこで、本実施の形態では、実際に放出電子が到達するコレクタ電極 32と上部電 極 18間の電界を調整する方法を採用した。これにより、輝度ばらつきの調整を直接 的に行うことができ、迅速に、かつ、精度よく輝度ばらつきを低減することができる。  [0154] Therefore, in the present embodiment, a method of adjusting the electric field between the collector electrode 32 and the upper electrode 18 where the emitted electrons actually reach has been adopted. As a result, the luminance variation can be directly adjusted, and the luminance variation can be reduced quickly and accurately.
[0155] 具体的に、本実施の形態に係る輝度ばらつきの低減方法を説明する。図 25に示 すように、上部電極 18と、該上部電極 18と下部電極 20間に負電圧 Vk (例えば上述 した電圧 Va2と同じ電圧）を印加するための負電源 70との間に接続された抵抗 Rkと 、コレクタ電極 32とバイアス電源 36 (バイアス電圧 Vc)との間に接続された抵抗 Rcと を調整する。図 25において、抵抗 Rkcは、上部電極 18とコレクタ電極 32間のギヤッ プによる抵抗を示し、電圧 Vkcは、ギャップ間の電圧を示す。また、 Cは上部電極 18 と下部電極 20間の容量、電圧 Vakは上部電極 18と下部電極 20間の電圧を示す。  [0155] Specifically, a method for reducing luminance variations according to the present embodiment will be described. As shown in FIG. 25, it is connected between the upper electrode 18 and a negative power source 70 for applying a negative voltage Vk (for example, the same voltage as the voltage Va2 described above) between the upper electrode 18 and the lower electrode 20. And the resistor Rc connected between the collector electrode 32 and the bias power source 36 (bias voltage Vc). In FIG. 25, the resistance Rkc indicates the resistance due to the gap between the upper electrode 18 and the collector electrode 32, and the voltage Vkc indicates the voltage between the gaps. C represents the capacitance between the upper electrode 18 and the lower electrode 20, and the voltage Vak represents the voltage between the upper electrode 18 and the lower electrode 20.
[0156] ここで、 2つの電子放出素子 12A(1)及び 12A (2)を想定し、これら 2つの電子放 出素子 12A(1)及び 12A(2)の出力特性 (Vkc— Ike特性）が図 27に示すようにばら つきがあつたとき、前記抵抗 Rk及び Rcが存在しない場合、これら 2つの電子放出素 子 12A(1)及び 12A(2)における電流変動は Δ Ιとなる。  [0156] Here, assuming two electron-emitting devices 12A (1) and 12A (2), the output characteristics (Vkc-Ike characteristics) of these two electron-emitting devices 12A (1) and 12A (2) are As shown in FIG. 27, when the resistances Rk and Rc do not exist when there is variation, the current fluctuation in these two electron-emitting devices 12A (1) and 12A (2) becomes ΔΙ.
1  1
[0157] しかし、前記抵抗 Rk及び Rcを接続することで、前記電流変動 Δ Iを、負荷線 80上  However, by connecting the resistors Rk and Rc, the current fluctuation ΔI is reduced on the load line 80.
1  1
での電流変動 Δ Ιまで小さくすることができる。  The current fluctuation at Δ can be reduced to Δ Δ.
2  2
[0158] 負荷線 80は以下のようにして導くことができる。すなわち、図 25に示す構成図に基 づいて上部電極 18とコレクタ電極 32との間に流れる電流 Ikeを主体にした等価回路 を示すと図 26のようになる。  [0158] The load line 80 can be guided as follows. That is, FIG. 26 shows an equivalent circuit based on the current Ike flowing between the upper electrode 18 and the collector electrode 32 based on the configuration diagram shown in FIG.
[0159] この等価回路から、以下の式が導かれる。 From this equivalent circuit, the following expression is derived.
[0160] Ike = (Vk+Vc) / (Rc + Rkc + Rk) [0160] Ike = (Vk + Vc) / (Rc + Rkc + Rk)
ここで、 Rkc = 0のとき、 Ikeが最大となるから、図 27の縦軸上、  Here, when Rkc = 0, Ike is the maximum, so on the vertical axis in Fig. 27,
Ike = (Vk+Vc) / (Rc + Rk)  Ike = (Vk + Vc) / (Rc + Rk)
を示すポイント Paと、横軸上、 Vkc=Vk+Vcを示すポイント Pbとを結ぶ線が負荷線 80となる。  The load line 80 is a line connecting the point Pa indicating the point and the point Pb indicating Vkc = Vk + Vc on the horizontal axis.
[0161] そして、 Rc+Rkが大きいほど、電流 Ikeは小さくなる力 電子放出素子 12A(1)及 び 12A(2)間の輝度ばらつきは小さくなる。 [0161] And, as Rc + Rk increases, the current Ike decreases. Electron-emitting devices 12A (1) and And the brightness variation between 12A (2) is small.
[0162] また、上部電極 18とコレクタ電極 32間に図示しない制御電極を設置した場合、コレ クタ電極 32に流れるコレクタ電流 Icと制御電極に流れる制御電流 Igを主体にした等 価回路を示すと図 28のようになる。このとき、制御電極と、該制御電極と下部電極 20 間に負電圧 Vgを印加するための負電源 72との間に抵抗 Rgを接続する。なお、図 2 8の抵抗 Rkgは、上部電極 18と制御電極間のギャップによる抵抗を示す。また、この 例では、コレクタ電流 Icは力ソード電流 Ikの 60%とし、制御電流 Igは力ソード電流 Ik の 40%としている。  [0162] Further, when a control electrode (not shown) is installed between the upper electrode 18 and the collector electrode 32, an equivalent circuit mainly composed of the collector current Ic flowing through the collector electrode 32 and the control current Ig flowing through the control electrode is shown. It looks like Figure 28. At this time, a resistor Rg is connected between the control electrode and a negative power source 72 for applying a negative voltage Vg between the control electrode and the lower electrode 20. The resistance Rkg in FIG. 28 indicates the resistance due to the gap between the upper electrode 18 and the control electrode. In this example, the collector current Ic is 60% of the force sword current Ik, and the control current Ig is 40% of the force sword current Ik.
[0163] 図 28の等価回路から、以下の式が導かれる。  [0163] The following equation is derived from the equivalent circuit of Fig. 28.
[0164] Ig = (Vg + Vk) / (Rg + Rkg + Rk)  [0164] Ig = (Vg + Vk) / (Rg + Rkg + Rk)
この式に基づいて負荷線を引き、輝度ばらつきが最小となる電圧 Vgと抵抗 Rgを決 定すればよい。電圧 Vg及び抵抗 Rgが決定することによって、制御電流 Ig並びにカソ ード電流 Ikが決定し、必然的にコレクタ電流 Icも決定する。  A load line is drawn based on this equation, and the voltage Vg and resistance Rg that minimize the luminance variation can be determined. By determining the voltage Vg and the resistance Rg, the control current Ig and the cathode current Ik are determined, and the collector current Ic is inevitably determined.
[0165] 上述の第 1の実施の形態に係る光源 10Aでは、全ての電子放出素子 12Aを含む 1 つの発光部 14Aを有し、該発光部 14Aに対して 1つの駆動回路 16 Aを接続するよう にしたが、その他、図 29の第 5の変形例に係る光源 lOAeのように、 2以上の面光源 部 Z1— Z6を有するようにしてもよい。図 29の例では、 6つの面光源部 Z1— Z6を具 備させた場合を示す。各面光源部 Z1— Z6は、複数の電子放出素子 12Aが二次元 的に配列されて構成され、それぞれ独立に駆動回路 16Aが接続されている。  [0165] The light source 10A according to the first embodiment described above has one light emitting unit 14A including all the electron-emitting devices 12A, and one drive circuit 16A is connected to the light emitting unit 14A. However, in addition, as in the light source lOAe according to the fifth modification of FIG. 29, two or more surface light source units Z1 to Z6 may be provided. In the example of FIG. 29, the case where six surface light source units Z1-Z6 are provided is shown. Each surface light source unit Z1-Z6 is configured by two-dimensionally arranging a plurality of electron-emitting devices 12A, and a drive circuit 16A is independently connected thereto.
[0166] これによつて、面光源部 Z1— Z6単位に発光 Z消光を制御することができ、段階的 な調光 (デジタル的な調光)を行うことができる。特に、各面光源部 Z1— Z6にそれぞ れ独立に接続される駆動回路 16Aに変調回路 60 (図 18参照）を設けることによって 、各面光源部 Z1— Z6の発光分布をそれぞれ独立に制御することができる。つまり、 デジタル的な調光にカ卩えて、アナログ的な調光を実現でき、きめ細かな調光を行うこ とがでさる。  [0166] This makes it possible to control light emission Z quenching in units of the surface light source units Z1 to Z6, and to perform stepwise light control (digital light control). In particular, by providing a modulation circuit 60 (see Fig. 18) in the drive circuit 16A that is independently connected to each surface light source unit Z1-Z6, the emission distribution of each surface light source unit Z1-Z6 can be controlled independently. can do. In other words, analog dimming can be realized in addition to digital dimming, and fine dimming can be performed.
[0167] 図 29の例では、各面光源部 Z1— Z6の面積をそれぞれ同じにした場合を示したが 、各面光源部 Z1— Z6の面積を異ならせるようにしてもよい。例えば図 30に示す第 6 の変形例に係る光源 lOAfでは、第 1及び第 6の面光源部 Z1及び Z6をそれぞれ横 長で、かつ、長辺の長い長方形状とし、第 2及び第 5の面光源部をそれぞれ縦長で、 かつ、長辺が第 1及び第 6の面光源部 Z1及び Z6よりも短い長方形状とし、第 3及び 第 4の面光源部をそれぞれ横長で、かつ、長辺が第 1及び第 6の面光源部 Z1及び Z 6よりも短 ヽ長方形状とした場合を示す。 In the example of FIG. 29, the area of each surface light source unit Z1-Z6 is shown to be the same, but the area of each surface light source unit Z1-Z6 may be different. For example, in the light source lOAf according to the sixth modified example shown in FIG. 30, the first and sixth surface light source units Z1 and Z6 are respectively disposed laterally. The rectangular shape has a long and long side, and the second and fifth surface light source sections are each vertically long and the long side is shorter than the first and sixth surface light source sections Z1 and Z6. The case where the third and fourth surface light source parts are each horizontally long and the long side is shorter than the first and sixth surface light source parts Z1 and Z6 is shown.
[0168] また、図 31に示す第 7の変形例に係る光源 lOAgのように、各面光源部 Z1— Z6に 含まれる複数の電子放出素子 12Aをそれぞれ 2つのグループ (第 1及び第 2のダル ープ G1及び G2)に分け、各面光源部 Z1— Z6において、第 1のグループに含まれる 電子放出素子 12Aの発光時に、該第 1のグループ G1に含まれる電子放出素子 12 Aの電力を、第 2のグループ G2に含まれる電子放出素子 12Aに回収し、第 2のダル ープ G2に含まれる電子放出素子 12Aの発光時に、該第 2のグループ G2に含まれる 電子放出素子 12 Aの電力を、第 1のグループ G 1に含まれる電子放出素子 12Aに回 収するようにしてちょい。  In addition, as in the light source lOAg according to the seventh modification shown in FIG. 31, each of the plurality of electron-emitting devices 12A included in each surface light source unit Z1-Z6 is divided into two groups (first and second In each of the surface light sources Z1 to Z6, the power of the electron-emitting devices 12A included in the first group G1 is emitted at the time of light emission of the electron-emitting devices 12A included in the first group. Is collected in the electron-emitting device 12A included in the second group G2, and when the electron-emitting device 12A included in the second loop G2 emits light, the electron-emitting device 12 A included in the second group G2 So that the power is collected in the electron-emitting device 12A included in the first group G1.
[0169] あるいは、図 32に示す第 8の変形例に係る光源 lOAhのように、 6つの面光源部 Z1 一 Z6を 2つのグループ（第 1及び第 2のグループ G1及び G2)〖こ分け、第 1のグルー プ G1に関する面光源部 Z1— Z3の各電子放出素子 12Aの発光時に、これら電子放 出素子 12Aの電力を、第 2のグループ G2に関する面光源部 Z4— Z6の電子放出素 子 12Aに回収し、第 2のグループ G2に関する面光源部 Z4— Z6の各電子放出素子 12Aの発光時に、これら電子放出素子 12Aの電力を、第 1のグループ G1に関する 面光源部 Z1— Z3の電子放出素子 12Aに回収するようにしてもょ 、。  [0169] Alternatively, like the light source lOAh according to the eighth modification shown in Fig. 32, the six surface light source units Z1 and Z6 are divided into two groups (first and second groups G1 and G2), The surface light source units Z1-Z3 related to the first group G1 emit light from the electron-emitting devices 12A. The power of the electron-emitting devices 12A is used as the electron emission elements of the surface light source unit Z4-Z6 related to the second group G2. At the time of light emission from each of the electron emitters 12A of the surface light source unit Z4—Z6 related to the second group G2, the power of these electron emitters 12A is used as the electrons of the surface light source unit Z1—Z3 related to the first group G1. Let's collect it in the emitting element 12A.
[0170] 上述した第 5—第 8の変形例に係る光源 lOAe— lOAhでは、発光部 14Aを 6つの 面光源部 Z1— Z6に分離した例を示したが、面光源部の数は任意に設定することが できる。  [0170] In the light sources lOAe- lOAh according to the fifth to eighth modifications described above, the example in which the light emitting unit 14A is separated into the six surface light source units Z1-Z6 is shown, but the number of the surface light source units is arbitrary. Can be set.
[0171] ところで、第 1の実施の形態に係る光源 10Aは、図 1に示すように、 1つのェミッタ部 22の表面にそれぞれ独立に複数の上部電極 18を形成し、ェミッタ部 22の裏面にそ れぞれ独立に複数の下部電極 20を形成して複数の電子放出素子 12Aを形成する ようにした力 その他、以下に示すような他の実施の形態が考えられる。なお、図 33 一図 37において、コレクタ電極 32や蛍光体 34の表記を省略する。  By the way, as shown in FIG. 1, the light source 10A according to the first embodiment has a plurality of upper electrodes 18 formed independently on the surface of one emitter section 22, and on the back surface of the emitter section 22. The force in which a plurality of lower electrodes 20 are formed independently to form a plurality of electron-emitting devices 12A, and other embodiments other than those shown below are conceivable. In FIG. 33 and FIG. 37, the collector electrode 32 and the phosphor 34 are not shown.
[0172] すなわち、図 33の第 9の変形例に係る光源 lOAiは、 1つのェミッタ部 22の表面に それぞれ独立に複数の上部電極 18を形成し、ェミッタ部 22の裏面に 1つの下部電 極 20 (共通の下部電極)を形成して複数の電子放出素子 12Aを形成した場合を示 す。 That is, the light source lOAi according to the ninth modification of FIG. 33 is formed on the surface of one emitter section 22. A case is shown in which a plurality of upper electrodes 18 are formed independently, and one lower electrode 20 (common lower electrode) is formed on the back surface of the emitter section 22 to form a plurality of electron-emitting devices 12A.
[0173] 図 34の第 10の変形例に係る光源 lOAjは、 1つのェミッタ部 22の表面に 1つの極 薄（一 10nm)の上部電極 18 (共通の上部電極)を形成し、ェミッタ部 22の裏面にそ れぞれ独立に複数の下部電極 20を形成して複数の電子放出素子 12Aを形成した 場合を示す。  In the light source lOAj according to the tenth modification example of FIG. 34, one ultrathin (one 10 nm) upper electrode 18 (common upper electrode) is formed on the surface of one emitter 22, and the emitter 22 A case is shown in which a plurality of lower electrodes 20 are formed independently on the back surface of each of the plurality of electron-emitting devices 12A.
[0174] 図 35の第 11の変形例に係る光源 lOAkは、基板 90上に複数の下部電極 20をそ れぞれ独立に形成し、これら下部電極 20を覆うように 1つのェミッタ部 22を形成し、 更に、ェミッタ部 22上に複数の上部電極 18をそれぞれ独立して形成して複数の電 子放出素子 12Aを形成した場合を示す。各上部電極 18は、それぞれ対応する下部 電極 20上にェミッタ部 22を間に挟んで形成される。  [0174] The light source lOAk according to the eleventh modification example of FIG. 35 has a plurality of lower electrodes 20 formed independently on a substrate 90, and a single emitter portion 22 so as to cover these lower electrodes 20. Further, a case is shown in which a plurality of upper electrodes 18 are independently formed on the emitter section 22 to form a plurality of electron-emitting devices 12A. Each upper electrode 18 is formed on a corresponding lower electrode 20 with an emitter portion 22 interposed therebetween.
[0175] 図 36の第 12の変形例に係る光源 10A1は、基板 90上に 1つの下部電極 20を形成 し、該下部電極 20を覆うように 1つのェミッタ部 22を形成し、更に、ェミッタ部 22上に 複数の上部電極 18をそれぞれ独立に形成して複数の電子放出素子 12Aを形成し た場合を示す。  [0175] In the light source 10A1 according to the twelfth modification of FIG. 36, one lower electrode 20 is formed on a substrate 90, one emitter 22 is formed so as to cover the lower electrode 20, and A case where a plurality of upper electrodes 18 are independently formed on the portion 22 to form a plurality of electron-emitting devices 12A is shown.
[0176] 図 37の第 13の変形例に係る光源 lOAmは、基板 90上に複数の下部電極 20をそ れぞれ独立に形成し、これら複数の下部電極 20を覆うように 1つのェミッタ部 22を形 成し、更に、ェミッタ部 22上に 1つの極薄の上部電極 18を形成して複数の電子放出 素子 12 Aを形成した場合を示す。  [0176] In the light source lOAm according to the thirteenth modified example of FIG. 37, a plurality of lower electrodes 20 are independently formed on the substrate 90, and one emitter section is formed so as to cover the plurality of lower electrodes 20. 22 shows a case where a plurality of electron-emitting devices 12 A are formed by forming one ultrathin upper electrode 18 on the emitter 22.
[0177] 次に、第 2の実施の形態に係る光源 10Bについて図 38—図 77を参照しながら説 明する。なお、第 1の実施の形態と対応するものについては同符号を付してその重複 説明を省略する。  Next, a light source 10B according to the second embodiment will be described with reference to FIGS. 38 to 77. FIG. Note that components corresponding to those in the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.
[0178] 第 2の実施の形態に係る光源 10Bの電子放出素子 12Bは、図 38に示すように、上 述したェミッタ部 22、上部電極 18及び下部電極 20並びに上部電極 18と下部電極 2 0との間に、駆動電圧 Vaを印加するパルス発生源 100とを有する。  As shown in FIG. 38, the electron emitter 12B of the light source 10B according to the second embodiment includes the above-described emitter unit 22, the upper electrode 18, the lower electrode 20, and the upper electrode 18 and the lower electrode 20. And a pulse generation source 100 for applying a driving voltage Va.
[0179] 上部電極 18は、ェミッタ部 22が露出される複数の貫通部 102を有する。特に、エミ ッタ部 22の表面は、誘電体の粒界による凹凸 104が形成されており、上部電極 18の 貫通部 102は、前記誘電体の粒界における凹部 106に対応した部分に形成されて いる。図 38の例では、 1つの凹部 106に対応して 1つの貫通部 102が形成される場 合を示しているが、複数の凹部 106に対応して 1つの貫通部 102が形成される場合 もある。ェミッタ部 22を構成する誘電体の粒径は、 0. 1 m— 10 mが好ましぐさら に好ましくは 2 μ m— 7 μ mである。図 38の例では、誘電体の粒径を 3 μ mとしている The upper electrode 18 has a plurality of through portions 102 from which the emitter portion 22 is exposed. In particular, the surface of the emitter portion 22 has irregularities 104 formed by dielectric grain boundaries. The through portion 102 is formed in a portion corresponding to the concave portion 106 in the dielectric grain boundary. In the example of FIG. 38, the case where one penetration 102 is formed corresponding to one recess 106 is shown, but the case where one penetration 102 is formed corresponding to a plurality of depressions 106 is also shown. is there. The particle size of the dielectric constituting the emitter portion 22 is preferably 0.1 m-10 m, and more preferably 2 μm-7 μm. In the example of Fig. 38, the dielectric particle size is 3 μm.
[0180] さらに、この第 2の実施の形態では、図 39に示すように、上部電極 18のうち、貫通 部 102の周部 108におけるェミッタ部 22と対向する面 108aが、ェミッタ部 22から離 間している。つまり、上部電極 18のうち、貫通部 102の周部 108におけるェミッタ部 2 2と対向する面 108aとェミッタ部 22との間にギャップ 110が形成され、上部電極 18に おける貫通部 102の周部 108が庇状 (フランジ状）に形成された形となっている。従つ て、以下の説明では、「上部電極 18の貫通部 102の周部 108」を「上部電極 18の庇 部 108」と記す。なお、図 38、図 39、図 41A、図 41B、図 42A、図 42B、図 44、図 46 一図 49、図 54の例では、誘電体の粒界の凹凸 104の凸部 112の断面を代表的に 半円状で示してあるが、この形状に限るものではな!/、。 Furthermore, in the second embodiment, as shown in FIG. 39, the surface 108 a of the upper electrode 18 facing the emitter portion 22 in the peripheral portion 108 of the penetrating portion 102 is separated from the emitter portion 22. I'm waiting. That is, in the upper electrode 18, a gap 110 is formed between the surface 108a of the peripheral portion 108 of the penetrating portion 102 facing the emitter portion 22 and the emitter portion 22, and the peripheral portion of the penetrating portion 102 in the upper electrode 18 is formed. 108 is formed in a bowl shape (flange shape). Therefore, in the following description, “the peripheral portion 108 of the through portion 102 of the upper electrode 18” is referred to as “the upper portion 108 of the upper electrode 18”. In the examples of FIGS. 38, 39, 41A, 41B, 42A, 42B, 44, 46, 46, 49, and 54, the cross section of the protrusion 112 of the unevenness 104 of the dielectric grain boundary is shown. Typically, it is shown in a semicircular shape, but it is not limited to this shape! /.
[0181] また、この第 2の実施の形態では、上部電極 18の厚み tを、 0. 01 m≤t≤ 10 m とし、ェミッタ部 22の上面、すなわち、誘電体の粒界における凸部 112の表面（凹部 106の内壁面でもある）と、上部電極 18の庇部 108の下面 108aとのなす角の最大角 度 0を、 1° ≤ 0≤60° としている。また、ェミッタ部 22の誘電体の粒界における凸 部 112の表面（凹部 106の内壁面）と、上部電極 18の庇部 108の下面 108aとの間 の鉛直方向に沿った最大間隔 dを、 0 ^ ιη< ά≤10 ^ mとして 、る。  In the second embodiment, the thickness t of the upper electrode 18 is set to 0.01 m ≦ t ≦ 10 m, and the upper surface of the emitter 22, that is, the protrusion 112 at the grain boundary of the dielectric. The maximum angle 0 formed by the surface of the upper electrode 18 (which is also the inner wall surface of the recess 106) and the lower surface 108a of the flange 108 of the upper electrode 18 is set to 1 ° ≤ 0≤60 °. Further, the maximum distance d along the vertical direction between the surface of the convex portion 112 (the inner wall surface of the concave portion 106) and the lower surface 108a of the flange portion 108 of the upper electrode 18 at the dielectric grain boundary of the emitter portion 22 is 0 ^ ιη <ά≤10 ^ m
[0182] さらに、この第 2の実施の形態では、貫通部 102の形状、特に、図 40に示すように、 上面から見た形状は孔 114の形状であって、例えば円形状、楕円形状、トラック状の ように、曲線部分を含むものや、四角形や三角形のように多角形状のものがある。図 40の例では、孔 114の形状として円形状の場合を示している。  [0182] Further, in the second embodiment, as shown in Fig. 40, the shape of the penetrating part 102 is the shape of the hole 114, for example, a circular shape, an elliptical shape, There are those that include a curved portion such as a track shape, and polygonal shapes such as a square and a triangle. In the example of FIG. 40, the hole 114 has a circular shape.
[0183] この場合、孔 114の平均径は、 0. 1 m以上、 10 μ m以下として!/、る。この平均径 は、孔 114の中心を通るそれぞれ異なる複数の線分の長さの平均を示す。  [0183] In this case, the average diameter of the holes 114 should be 0.1 m or more and 10 μm or less! This average diameter represents the average of the lengths of a plurality of different line segments passing through the center of the hole 114.
[0184] なお、ェミッタ部 22の構成材料は、上述した第 1の実施の形態と同様であるため、 その説明を省略する。 [0184] The constituent material of the emitter section 22 is the same as that in the first embodiment described above. The description is omitted.
[0185] ェミッタ部 22を形成する方法としては、スクリーン印刷法、デイツビング法、塗布法、 電気泳動法、エアロゾルデポジション法等の各種厚膜形成法や、イオンビーム法、ス パッタリング法、真空蒸着法、イオンプレーティング法、化学気相成長法 (CVD)、め つき等の各種薄膜形成法を用いることができる。特に、圧電 Z電歪材料の粉末化し たものを、ェミッタ部 22として形成し、これに低融点のガラスゃゾル粒子を含浸する方 法をとることが好ましい。この手法により、 700°Cあるいは 600°C以下といった低温で の膜形成が可能となる。  [0185] As the method of forming the emitter section 22, various thick film forming methods such as a screen printing method, a dating method, a coating method, an electrophoresis method, an aerosol deposition method, an ion beam method, a sputtering method, a vacuum Various thin film forming methods such as vapor deposition, ion plating, chemical vapor deposition (CVD), and plating can be used. In particular, it is preferable to use a method in which a powdered piezoelectric Z electrostrictive material is formed as the emitter portion 22 and impregnated with glass sol particles having a low melting point. This technique enables film formation at low temperatures such as 700 ° C or 600 ° C or lower.
[0186] 上部電極 18は、焼成後に薄い膜が得られる有機金属ペーストが用いられる。例え ば白金レジネートペースト等の材料を用いることが好ましい。また、分極反転疲労を 抑制する酸化物電極、例えば、酸化ルテニウム (RuO )、酸化イリジウム (IrO )、ル  [0186] The upper electrode 18 is made of an organic metal paste that provides a thin film after firing. For example, a material such as platinum resinate paste is preferably used. Also, oxide electrodes that suppress polarization reversal fatigue such as ruthenium oxide (RuO), iridium oxide (IrO), ruthenium
2 2 テニゥム酸ストロンチウム（SrRuO )、 La Sr CoO (例えば χ = 0· 3や 0· 5)、 La  2 2 Strontium teniumate (SrRuO), La Sr CoO (eg χ = 0 · 3 or 0 · 5), La
3 1-χ χ 3 1-χ 3 1-χ χ 3 1-χ
Ca ΜηΟ (例えば χ = 0· 2)、 La Ca Μη Co Ο (例えば χ = 0· 2、 y=0. 05)、も x 3 1-x x 1-y y 3 Ca ΜηΟ (e.g. χ = 0-2), La Ca Μη Co Ο (e.g. χ = 0-2, y = 0. 05), x 3 1-x x 1-y y 3
しくはこれらを例えば白金レジネートペーストに混ぜたものが好ま 、。  For example, a mixture of these in platinum resinate paste is preferable.
[0187] また、上部電極 18として、図 41A及び図 41Bに示すように、複数の鱗片状の形状 を有する物質 116 (例えば黒鉛)の集合体 118や、図 42A及び図 42Bに示すように、 鱗片状の形状を有する物質 116を含んだ導電性の物質 120の集合体 122も好ましく 用いられる。この場合、前記集合体 118や集合体 122でェミッタ部 22の表面を完全 に覆うのではなぐェミッタ部 22がー部露出する貫通部 102を複数設けて、ェミッタ部 22のうち、貫通部 102を臨む部分を電子放出領域とする。 Further, as the upper electrode 18, as shown in FIGS. 41A and 41B, an aggregate 118 of substances 116 (for example, graphite) having a plurality of scale-like shapes, or as shown in FIGS. 42A and 42B, An aggregate 122 of conductive substances 120 including a substance 116 having a scale-like shape is also preferably used. In this case, a plurality of penetrating portions 102 where the emitter portion 22 does not completely cover the surface of the emitter portion 22 with the aggregate 118 or the aggregate 122 are provided. The part that faces is an electron emission region.
[0188] 上部電極 18は、上記材料を用いて、スクリーン印刷、スプレー、コーティング、ディ ッビング、塗布、電気泳動法等の各種の厚膜形成法や、スパッタリング法、イオンビ ーム法、真空蒸着法、イオンプレーティング法、化学気相成長法 (CVD)、めっき等 の各種の薄膜形成法による通常の膜形成法に従って形成することができ、好適には 、前者の厚膜形成法によって形成するとよい。 [0188] The upper electrode 18 is made of the above-mentioned materials using various thick film forming methods such as screen printing, spraying, coating, dubbing, coating, and electrophoresis, sputtering, ion beam, and vacuum deposition. , Ion plating, chemical vapor deposition (CVD), and various other thin film formation methods such as plating, can be formed according to a normal film formation method, preferably the former thick film formation method .
[0189] 一方、下部電極 20は、導電性を有する物質、例えば金属が用いられ、白金、モリブ デン、タングステン等によって構成される。また、高温酸化雰囲気に対して耐性を有 する導体、例えば金属単体、合金、絶縁性セラミックスと金属単体との混合物、絶縁 性セラミックスと合金との混合物等によって構成され、好適には、白金、イリジウム、パ ラジウム、ロジウム、モリブデン等の高融点貴金属や、銀-パラジウム、銀-白金、白金On the other hand, the lower electrode 20 is made of a conductive material, such as metal, and is made of platinum, molybdenum, tungsten, or the like. Also, conductors resistant to high-temperature oxidizing atmospheres, such as simple metals, alloys, mixtures of insulating ceramics and simple metals, insulation Preferably a high melting point noble metal such as platinum, iridium, palladium, rhodium, molybdenum, silver-palladium, silver-platinum, platinum, etc.
-パラジウム等の合金を主成分とするものや、白金とセラミック材料とのサーメット材料 によって構成される。さら〖こ好適〖こは、白金のみ又は白金系の合金を主成分とする材 料によって構成される。 -Consists of alloys mainly composed of alloys such as palladium and cermet materials of platinum and ceramic materials. Further, the preferred coconut paste is composed of a material mainly composed of platinum or a platinum-based alloy.
[0190] また、下部電極 20として、カーボン、グラフアイト系の材料を用いてもよい。なお、電 極材料中に添加されるセラミック材料の割合は、 5— 30体積％程度が好適である。も ちろん、上述した上部電極 18と同様の材料を用いるようにしてもょ 、。  [0190] Further, the lower electrode 20 may be made of carbon or graphite materials. The proportion of the ceramic material added to the electrode material is preferably about 5-30% by volume. Of course, you may use the same material as the upper electrode 18 mentioned above.
[0191] 下部電極 20は、好適には上記厚膜形成法によって形成する。下部電極 20の厚さ は、 20 m以下であるとよぐ好適には 5 m以下であるとよい。  [0191] The lower electrode 20 is preferably formed by the thick film forming method. The thickness of the lower electrode 20 is preferably 20 m or less, and preferably 5 m or less.
[0192] ェミッタ部 22、上部電極 18及び下部電極 20をそれぞれ形成するたびに熱処理（ 焼成処理)することで、一体構造にすることができる。  [0192] An integral structure can be obtained by performing heat treatment (firing treatment) each time the emitter section 22, the upper electrode 18, and the lower electrode 20 are formed.
[0193] ェミッタ部 22、上部電極 18及び下部電極 20を一体化させるための焼成処理に係 る温度としては、 500— 1400°Cの範囲、好適には、 1000— 1400°Cの範囲とすると よい。さらに、膜状のェミッタ部 22を熱処理する場合、高温時にェミッタ部 22の組成 が不安定にならな 、ように、ェミッタ部 22の蒸発源と共に雰囲気制御を行 、ながら焼 成処理を行うことが好まし 、。  [0193] The temperature related to the firing treatment for integrating the emitter section 22, the upper electrode 18 and the lower electrode 20 is in the range of 500-1400 ° C, preferably in the range of 1000-1400 ° C. Good. Further, when the film-like emitter 22 is heat-treated, the firing process can be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the composition of the emitter 22 is not unstable at high temperatures. I like it.
[0194] 焼成処理を行うことで、特に、上部電極 18となる膜が例えば厚み 10 mから厚み 0 . ： mに収縮すると同時に複数の孔等が形成されていき、結果的に、図 38に示す ように、上部電極 18に複数の貫通部 102が形成され、貫通部 102の周部 108が庇 状に形成された構成となる。もちろん、上部電極 18となる膜に対して事前 (焼成前） にエッチング（ウエットエッチング、ドライエッチング)やリフトオフ等によってパターン- ングを施した後、焼成するようにしてもよい。この場合、後述するように、貫通部 102と して切欠き形状やスリット形状を容易に形成することができる。  [0194] By performing the firing treatment, in particular, the film that becomes the upper electrode 18 contracts from, for example, a thickness of 10 m to a thickness of 0.0 m, and a plurality of holes are formed at the same time. As shown, a plurality of through portions 102 are formed in the upper electrode 18, and the peripheral portion 108 of the through portion 102 is formed in a bowl shape. Of course, the film to be the upper electrode 18 may be subjected to patterning by etching (wet etching, dry etching), lift-off, or the like in advance (before firing) and then fired. In this case, as will be described later, a notch shape or a slit shape can be easily formed as the penetrating portion 102.
[0195] なお、ェミッタ部 22を適切な部材によって被覆し、該ェミッタ部 22の表面が焼成雰 囲気に直接露出しな 、ようにして焼成する方法を採用してもよ 、。 [0195] It should be noted that a method may be employed in which the emitter portion 22 is covered with an appropriate member and the surface of the emitter portion 22 is not directly exposed to the firing atmosphere.
[0196] 次に、電子放出素子 12Bの電子放出原理について説明する。先ず、上部電極 18 と下部電極 20との間に駆動電圧 Vaが印加される。この駆動電圧 Vaは、例えば、パ ルス電圧あるいは交流電圧のように、時間の経過に伴って、基準電圧 (例えば OV)よ りも高 ヽ又は低 ヽ電圧レベルから基準電圧よりも低!ヽ又は高!、電圧レベルに急激に 変化する電圧として定義される。 Next, the principle of electron emission of the electron emitter 12B will be described. First, the drive voltage Va is applied between the upper electrode 18 and the lower electrode 20. This drive voltage Va is, for example, Over time, the voltage level is higher or lower than the reference voltage (e.g., OV), but lower than the reference voltage! Or higher! Defined as the voltage to
[0197] また、ェミッタ部 22の上面と上部電極 18と該電子放出素子 12Bの周囲の媒質 (例 えば、真空）との接触箇所においてトリプルジャンクションが形成されている。ここで、 トリプルジャンクションとは、上部電極 18とェミッタ部 22と真空との接触により形成され る電界集中部として定義される。なお、前記トリプルジャンクションには、上部電極 18 とェミッタ部 22と真空が 1つのポイントとして存在する 3重点も含まれる。雰囲気中の 真空度は、 102— 10— 6Paが好ましぐより好ましくは 10— 3— 10— 5Paである。 [0197] Further, a triple junction is formed at a contact point between the upper surface of the emitter section 22, the upper electrode 18, and the medium (for example, vacuum) around the electron-emitting device 12B. Here, the triple junction is defined as an electric field concentration portion formed by contact of the upper electrode 18, the emitter portion 22, and the vacuum. The triple junction also includes a triple point where the upper electrode 18, the emitter 22 and the vacuum exist as one point. The degree of vacuum in the atmosphere is preferably 10 2 − 10− 6 Pa, more preferably 10 3 − 10− 5 Pa.
[0198] 第 2の実施の形態では、トリプルジャンクションは、上部電極 18の庇部 108や上部 電極 18の周縁部に形成されることになる。従って、上部電極 18と下部電極 20との間 に上述のような駆動電圧 Vaが印加されると、上記したトリプルジャンクションにおいて 電界集中が発生する。  In the second embodiment, the triple junction is formed at the flange portion 108 of the upper electrode 18 and the peripheral portion of the upper electrode 18. Therefore, when the drive voltage Va as described above is applied between the upper electrode 18 and the lower electrode 20, electric field concentration occurs in the triple junction described above.
[0199] ここで、電子放出素子 12Bの第 1の電子放出方式について図 43及び図 44を参照 しながら説明する。図 43の第 1の出力期間 T1 (第 1段階）において、上部電極 18に 基準電圧 (この場合、 OV)よりも低い電圧 V2が印加され、下部電極 20に基準電圧よ りも高い電圧 VIが印加される。この第 1の出力期間 T1では、上記したトリプルジヤン クシヨンにおいて電界集中が発生し、上部電極 18からェミッタ部 22に向けて電子放 出が行われ、例えばェミッタ部 22のうち、上部電極 18の貫通部 102から露出する部 分や上部電極 18の周縁部近傍の部分に電子が蓄積される。すなわち、ェミッタ部 2 2が帯電することになる。このとき、上部電極 18が電子供給源として機能する。  Here, the first electron emission method of the electron emitter 12B will be described with reference to FIGS. 43 and 44. FIG. In the first output period T1 (first stage) in FIG. 43, a voltage V2 lower than the reference voltage (in this case, OV) is applied to the upper electrode 18, and a voltage VI higher than the reference voltage is applied to the lower electrode 20. Applied. In the first output period T1, electric field concentration occurs in the triple junction described above, and electrons are emitted from the upper electrode 18 toward the emitter section 22. For example, in the emitter section 22, the upper electrode 18 penetrates through the upper electrode 18. Electrons are accumulated in the portion exposed from the portion 102 and the portion near the peripheral edge of the upper electrode 18. That is, the emitter part 22 is charged. At this time, the upper electrode 18 functions as an electron supply source.
[0200] 次の第 2の出力期間 T2 (第 2段階）において、駆動電圧 Vaの電圧レベルが急減に 変化、すなわち、上部電極 18に基準電圧よりも高い電圧 VIが印加され、下部電極 2 0に基準電圧よりも低い電圧 V2が印加されると、今度は、上部電極 18の貫通部 102 に対応した部分や上部電極 18の周縁部近傍に帯電した電子は、逆方向へ分極反 転したェミッタ部 22の双極子 (ェミッタ部 22の表面に負極性が現れる）により、ェミツ タ部 22から追い出され、図 44に示すように、ェミッタ部 22のうち、前記電子の蓄積さ れていた部分から、貫通部 102を通じて電子が放出される。もちろん、上部電極 18 の外周部近傍からも電子が放出される。 [0200] In the next second output period T2 (second stage), the voltage level of the drive voltage Va suddenly decreases, that is, the voltage VI higher than the reference voltage is applied to the upper electrode 18, and the lower electrode 2 0 When a voltage V2 lower than the reference voltage is applied to the upper electrode 18, this time, the electrons charged in the portion corresponding to the through-hole 102 of the upper electrode 18 and in the vicinity of the peripheral edge of the upper electrode 18 are polarized in the opposite direction. Due to the dipole of the part 22 (negative polarity appears on the surface of the emitter part 22), the part 22 is expelled from the emitter part 22, and as shown in FIG. 44, from the part where the electrons are accumulated in the emitter part 22. Electrons are emitted through the penetrating part 102. Of course, the upper electrode 18 Electrons are also emitted from the vicinity of the outer periphery of the.
[0201] 次に、第 2の電子放出方式について説明する。先ず、図 45の第 1の出力期間 Tl ( 第 1段階）において、上部電極 18に基準電圧よりも高い電圧 V3が印加され、下部電 極 20に基準電圧よりも低い電圧 V4が印加される。この第 1の出力期間 T1では、電 子放出のための準備 (例えばェミッタ部 22の一方向への分極等）が行われる。次の 第 2の出力期間 Τ2 (第 2段階）において、駆動電圧 Vaの電圧レベルが急減に変化、 すなわち、上部電極 18に基準電圧よりも低い電圧 V4が印加され、下部電極 20に基 準電圧よりも高い電圧 V3が印加されると、今度は、上記したトリプルジャンクションに おいて電界集中が発生し、この電界集中によって上部電極 18から 1次電子が放出さ れ、ェミッタ部 22のうち、貫通部 102から露出する部分並びに上部電極 18の外周部 近傍に衝突することとなる。これによつて、図 46に示すように、 1次電子が衝突した部 分から 2次電子（1次電子の反射電子を含む）が放出される。すなわち、第 2の出力期 間 T2の初期段階において、前記貫通部 102並びに上部電極 18の外周部近傍から 2次電子が放出されることとなる。  [0201] Next, the second electron emission method will be described. First, in the first output period Tl (first stage) in FIG. 45, a voltage V3 higher than the reference voltage is applied to the upper electrode 18, and a voltage V4 lower than the reference voltage is applied to the lower electrode 20. In the first output period T1, preparation for electron emission (for example, polarization in one direction of the emitter 22) is performed. In the next second output period Τ2 (second stage), the voltage level of the drive voltage Va changes suddenly, that is, the voltage V4 lower than the reference voltage is applied to the upper electrode 18, and the reference voltage is applied to the lower electrode 20. If a higher voltage V3 is applied, this time, an electric field concentration occurs at the triple junction described above, and the primary electrons are emitted from the upper electrode 18 due to the electric field concentration. The portion exposed from the portion 102 and the vicinity of the outer peripheral portion of the upper electrode 18 collide with each other. As a result, as shown in FIG. 46, secondary electrons (including reflected electrons of the primary electrons) are emitted from the portion where the primary electrons collide. That is, in the initial stage of the second output period T2, secondary electrons are emitted from the penetration part 102 and the vicinity of the outer peripheral part of the upper electrode 18.
[0202] そして、この電子放出素子 12Bにおいては、上部電極 18に複数の貫通部 102を形 成したことから、各貫通部 102並びに上部電極 18の外周部近傍力も均等に電子が 放出され、全体の電子放出特性のばらつきが低減し、電子放出の制御が容易になる と共に、電子放出効率が高くなる。  [0202] In this electron-emitting device 12B, since the plurality of through-holes 102 are formed in the upper electrode 18, electrons are evenly emitted from the force in the vicinity of the outer periphery of each through-hole 102 and the upper electrode 18. The variation in the electron emission characteristics is reduced, the electron emission is easily controlled, and the electron emission efficiency is increased.
[0203] また、第 2の実施の形態では、上部電極 18の庇部 108とェミッタ部 22との間にギヤ ップ 110が形成された形となることから、駆動電圧 Vaを印加した際に、該ギャップ 11 0の部分において電界集中が発生し易くなる。これは、電子放出の高効率ィ匕につな がり、駆動電圧の低電圧化 (低い電圧レベルでの電子放出）を実現させることができ る。  [0203] In the second embodiment, since the gap 110 is formed between the flange portion 108 and the emitter portion 22 of the upper electrode 18, the drive voltage Va is applied. Electric field concentration is likely to occur in the gap 110 part. This leads to high efficiency of electron emission, and can reduce the drive voltage (electron emission at a low voltage level).
[0204] 上述したように、第 2の実施の形態では、上部電極 18は、貫通部 102の周部にお いて庇部 108が形成されることから、上述したギャップ 110の部分での電界集中が大 きくなることとも相俟って、上部電極 18の庇部 108から電子が放出され易くなる。これ は、電子放出の高出力、高効率化につながり、駆動電圧 Vaの低電圧化を実現させ ることができる。これにより、例えば電子放出素子 12Bを多数並べて構成された第 2 の実施の形態に係る光源 10Bの高輝度化を図ることができる。 [0204] As described above, in the second embodiment, the upper electrode 18 has the flange portion 108 formed in the peripheral portion of the penetrating portion 102. Therefore, the electric field concentration in the gap 110 portion described above. In combination with the increase in the size, electrons are likely to be emitted from the flange portion 108 of the upper electrode 18. This leads to a high output and high efficiency of electron emission, and a low drive voltage Va can be realized. As a result, for example, a second configuration in which a large number of electron-emitting devices 12B are arranged side by side. The luminance of the light source 10B according to the embodiment can be increased.
[0205] また、上述した第 1の電子放出方式 (ェミッタ部 22に蓄積された電子を放出させる 方式)や第 2の電子放出方式 (上部電極 18からの 1次電子をェミッタ部 22に衝突させ て 2次電子を放出させる方式)のいずれにしても、上部電極 18の庇部 108がゲート電 極 (制御電極、フォーカス電子レンズ等）として機能するため、放出電子の直進性を 向上させることができる。これは、電子放出素子 12Bを多数並べて例えばディスプレ ィの電子源として構成した場合に、クロストークを低減する上で有利となる。  [0205] Also, the first electron emission method (method of emitting electrons accumulated in the emitter unit 22) and the second electron emission method (primary electrons from the upper electrode 18 are caused to collide with the emitter unit 22 as described above. In any case of the secondary electron emission method), the eaves 108 of the upper electrode 18 functions as a gate electrode (control electrode, focus electron lens, etc.), so that the straightness of the emitted electrons can be improved. it can. This is advantageous in reducing crosstalk when a large number of electron-emitting devices 12B are arranged to form, for example, a display electron source.
[0206] このように、第 2の実施の形態に係る光源 10Bにおいては、高い電界集中を容易に 発生させることができ、し力も、電子放出箇所を多くすることができ、電子放出につい て高出力、高効率を図ることができ、低電圧駆動 (低消費電力)も可能となる。  [0206] As described above, in the light source 10B according to the second embodiment, high electric field concentration can be easily generated, and the force can be increased, and the number of electron emission locations can be increased. Output and high efficiency can be achieved, and low voltage drive (low power consumption) is also possible.
[0207] 特に、第 2の実施の形態では、ェミッタ部 22の少なくとも上面は、誘電体の粒界によ る凹凸 104が形成され、上部電極 18は、誘電体の粒界における凹部 106に対応し た部分に貫通部 102が形成されるようにしたので、上部電極 18の庇部 108を簡単に 実現させることができる。  [0207] In particular, in the second embodiment, at least the upper surface of the emitter portion 22 is provided with irregularities 104 due to dielectric grain boundaries, and the upper electrode 18 corresponds to the concave portions 106 at the dielectric grain boundaries. Since the penetrating portion 102 is formed in the part, the flange portion 108 of the upper electrode 18 can be easily realized.
[0208] また、ェミッタ部 22の上面、すなわち、誘電体の粒界における凸部 112の表面（凹 部 106の内壁面）と、上部電極 18の庇部 108の下面 108aとのなす角の最大角度 0 を、 1° ≤ Θ≤60° とし、ェミッタ部 22の誘電体の粒界における凸部 112の表面（凹 部 106の内壁面）と、上部電極 18の庇部 108の下面 108aとの間の鉛直方向に沿つ た最大間隔 dを、 0 m< d≤ 10 mとしたので、これらの構成により、ギャップ 110の 部分での電界集中の度合いをより大きくすることができ、電子放出についての高出力 、高効率、並びに駆動電圧の低電圧化を効率よく図ることができる。  [0208] Further, the maximum angle between the upper surface of the emitter portion 22, that is, the surface of the convex portion 112 (inner wall surface of the concave portion 106) at the dielectric grain boundary, and the lower surface 108a of the flange portion 108 of the upper electrode 18 The angle 0 is set to 1 ° ≤ Θ ≤ 60 °, and the surface of the convex portion 112 (the inner wall surface of the concave portion 106) at the dielectric grain boundary of the emitter 22 and the lower surface 108a of the flange portion 108 of the upper electrode 18 Since the maximum distance d along the vertical direction between them is set to 0 m <d ≤ 10 m, these configurations can further increase the degree of electric field concentration in the gap 110 and reduce electron emission. High output, high efficiency, and low drive voltage can be efficiently achieved.
[0209] また、この第 2の実施の形態では、貫通部 102を孔 114の形状としている。図 39に 示すように、ェミッタ部 22のうち、上部電極 18と下部電極 20 (図 38参照）間に印加さ れる駆動電圧 Vaに応じて分極が反転あるいは変化する部分は、上部電極 18が形成 されている直下の部分 (第 1の部分） 124と、貫通部 102の内周から貫通部 102の内 方に向力 領域に対応した部分 (第 2の部分） 126であり、特に、第 2の部分 126は、 駆動電圧 Vaのレベルや電界集中の度合いによって変化することになる。従って、こ の第 2の実施の形態では、孔 114の平均径を、 0. l /z m以上、 10 /z m以下としてい る。この範囲であれば、貫通部 102を通じて放出される電子の放出分布にばらつきが ほとんどなくなり、効率よく電子を放出することができる。 [0209] Further, in the second embodiment, the penetrating portion 102 has the shape of the hole 114. As shown in FIG. 39, the upper electrode 18 is formed in the portion of the emitter 22 where the polarization is reversed or changed according to the drive voltage Va applied between the upper electrode 18 and the lower electrode 20 (see FIG. 38). And a portion (second portion) 126 corresponding to the directional force region from the inner periphery of the penetrating portion 102 to the inside of the penetrating portion 102, particularly the second portion. This portion 126 changes depending on the level of the driving voltage Va and the degree of electric field concentration. Therefore, in this second embodiment, the average diameter of the holes 114 is set to 0.1 l / zm or more and 10 / zm or less. The Within this range, there is almost no variation in the emission distribution of electrons emitted through the penetrating portion 102, and electrons can be efficiently emitted.
[0210] なお、孔 114の平均径が 0. 1 μ m未満の場合、電子を蓄積する領域が狭くなり、放 出される電子の量が少なくなる。もちろん、孔 114を多数設けることも考えられるが、 困難性を伴い、製造コストが高くなるという懸念がある。孔 114の平均径が 10 mを 超えると、ェミッタ部 22の前記貫通部 102から露出した部分のうち、電子放出に寄与 する部分 (第 2の部分） 126の割合（占有率)が小さくなり、電子の放出効率が低下す る。 [0210] When the average diameter of the holes 114 is less than 0.1 μm, the region for accumulating electrons becomes narrow, and the amount of electrons emitted is reduced. Of course, it is conceivable to provide a large number of holes 114, but there is a concern that the manufacturing cost increases with difficulty. When the average diameter of the holes 114 exceeds 10 m, the ratio (occupancy) of the portion (second portion) 126 that contributes to electron emission out of the portion exposed from the penetrating portion 102 of the emitter portion 22 decreases. Electron emission efficiency decreases.
[0211] 上部電極 18の庇部 108の断面形状としては、図 39に示すように、上面及び下面と も水平に延びる形状としてもよいし、図 47に示すように、庇部 108の下面 108aがほ ぼ水平であって、庇部 108の上端部が上方に盛り上がつていてもよい。また、図 48に 示すように、庇部 108の下面 108aが、貫通部 102の中心に向力 に従って徐々に上 方に傾斜していてもよいし、図 49に示すように、庇部 108の下面 108aが、貫通部 10 2の中心に向力うに従って徐々に下方に傾斜していてもよい。図 47の例は、ゲート電 極としての機能を高めることが可能であり、図 49の例では、ギャップ 110の部分が狭 くなることから、より電界集中を発生し易くなり、電子放出の高出力、高効率を向上さ せることができる。  [0211] The cross-sectional shape of the flange portion 108 of the upper electrode 18 may be a shape that extends horizontally along the upper surface and the lower surface, as shown in FIG. 39, or the lower surface 108a of the flange portion 108, as shown in FIG. However, the upper end of the flange 108 may be raised upward. Further, as shown in FIG. 48, the lower surface 108a of the flange portion 108 may be gradually inclined upward in accordance with the directional force at the center of the penetrating portion 102, or as shown in FIG. The lower surface 108a may be gradually inclined downward as it moves toward the center of the penetrating portion 102. The example in FIG. 47 can enhance the function as a gate electrode. In the example in FIG. 49, the gap 110 is narrowed, so that electric field concentration is more likely to occur, and electron emission is enhanced. Output and high efficiency can be improved.
[0212] また、この第 2の実施の形態においては、図 50に示すように、電気的な動作におい て、上部電極 18と下部電極 20間に、ェミッタ部 22によるコンデンサ C1と、各ギャップ 110による複数のコンデンサ Caの集合体とが形成された形となる。すなわち、各ギヤ ップ 110による複数のコンデンサ Caは、互いに並列に接続された 1つのコンデンサ C 2として構成され、等価回路的には、集合体によるコンデンサ C2にェミッタ部 22によ るコンデンサ C1が直列接続された形となる。  In the second embodiment, as shown in FIG. 50, in the electrical operation, between the upper electrode 18 and the lower electrode 20, the capacitor C1 by the emitter 22 and each gap 110 are provided. A plurality of capacitor Ca aggregates are formed. That is, a plurality of capacitors Ca by each gear 110 are configured as one capacitor C 2 connected in parallel to each other, and in terms of equivalent circuit, a capacitor C 1 by the emitter 22 is added to a capacitor C 2 by an aggregate. It becomes the form connected in series.
[0213] 実際には、集合体によるコンデンサ C2にェミッタ部 22によるコンデンサ C1がそのま ま直列接続されることはなぐ上部電極 18への貫通部 102の形成個数や全体の形成 面積等に応じて、直列接続されるコンデンサ成分が変化する。  [0213] Actually, the capacitor C2 from the aggregate is not directly connected in series with the capacitor C2 from the aggregate, depending on the number of through-holes 102 formed in the upper electrode 18 and the overall formation area. The capacitor component connected in series changes.
[0214] ここで、図 51に示すように、例えばェミッタ部 22によるコンデンサ C1のうち、その 25 %が集合体によるコンデンサ C2と直列接続された場合を想定して、容量計算を行つ てみる。先ず、ギャップ 110の部分は真空であることから比誘電率は 1となる。そして、 ギャップ 110の最大間隔 dを 0. 1 m、 1つのギャップ 110の部分の面積 S = l m X とし、ギャップ 110の数を 10, 000個とする。また、ェミッタ咅 の it誘電率を 2 000、ェミッタ部 22の厚みを 20 m、上部電極 18と下部電極 20の対向面積を 200 m X 200 /z mとすると、集合体によるコンデンサ C2の容量値は 0. 885pF、ェミッタ 部 22によるコンデンサ C1の容量値は 35. 4pFとなる。そして、ェミッタ部 22によるコ ンデンサ C1のうち、集合体によるコンデンサ C2と直列接続されている部分を全体の 25%としたとき、該直列接続された部分における容量値 (集合体によるコンデンサ C 2の容量値を含めた容量値）は 0. 805pFであり、残りの容量値は 26. 6pFとなる。 [0214] Here, as shown in FIG. 51, for example, the capacity calculation is performed assuming that 25% of the capacitor C1 by the emitter 22 is connected in series with the capacitor C2 by the aggregate. Try. First, since the gap 110 is vacuum, the relative dielectric constant is 1. The maximum distance d of the gap 110 is 0.1 m, the area S of one gap 110 is S = lm X, and the number of gaps 110 is 10,000. Also, if the it dielectric constant of the emitter is 2 000, the thickness of the emitter portion 22 is 20 m, and the opposing area of the upper electrode 18 and the lower electrode 20 is 200 m X 200 / zm, the capacitance value of the capacitor C2 by the aggregate is 0. 885pF, the capacitance value of the capacitor C1 by the emitter 22 is 35.4pF. Then, when the portion connected in series with the capacitor C2 by the aggregate in the capacitor C1 by the emitter section 22 is 25% of the total, the capacitance value in the portion connected in series (the capacitor C2 by the aggregate is The capacitance value including the capacitance value) is 0.805pF, and the remaining capacitance value is 26.6pF.
[0215] これら直列接続された部分と残りの部分は並列接続されているから、全体の容量値 は、 27. 5pFとなる。この容量値は、ェミッタ部 22によるコンデンサ C1の容量値 35. 4pFの 78%である。つまり、全体の容量値は、ェミッタ部 22によるコンデンサ C1の容 量値よりち/ J、さくなる。 [0215] Since the series-connected part and the remaining part are connected in parallel, the total capacitance value is 27.5 pF. This capacitance value is 78% of the capacitance value 35.4 pF of the capacitor C1 by the emitter 22. In other words, the overall capacitance value is less than the capacitance value of the capacitor C1 by the emitter unit 22 / J.
[0216] このように、複数のギャップ 110によるコンデンサ Caの集合体については、ギャップ 110によるコンデンサ Caの容量値が相対的に小さいものとなり、ェミッタ部 22によるコ ンデンサ C1との分圧から、印加電圧 Vaのほとんどはギャップ 110に印加されることに なり、各ギャップ 110において、電子放出の高出力化が実現される。  [0216] As described above, for the aggregate of the capacitor Ca by the plurality of gaps 110, the capacitance value of the capacitor Ca by the gap 110 becomes relatively small, and is applied from the partial pressure with the capacitor C1 by the emitter unit 22. Most of the voltage Va is applied to the gap 110, and in each gap 110, high output of electron emission is realized.
[0217] また、集合体によるコンデンサ C2は、ェミッタ部 22によるコンデンサ C1に直列接続 された構造となることから、全体の容量値は、ェミッタ部 22によるコンデンサ C1の容 量値よりも小さくなる。このことから、電子放出は高出力であり、全体の消費電力は小 さくなると 、う好まし 、特性を得ることができる。  [0217] Further, since the capacitor C2 by the aggregate has a structure connected in series to the capacitor C1 by the emitter section 22, the overall capacitance value is smaller than the capacitance value of the capacitor C1 by the emitter section 22. For this reason, the electron emission has a high output, and if the overall power consumption becomes small, it is preferable to obtain characteristics.
[0218] 次に、上述した第 2の実施の形態に係る光源 10Bの電子放出素子 12Bにおける 3 つの変形例について図 52—図 54を参照しながら説明する。  Next, three modified examples of the electron-emitting device 12B of the light source 10B according to the second embodiment described above will be described with reference to FIGS. 52 to 54. FIG.
[0219] 先ず、第 1の変形例に係る電子放出素子 12Baは、図 52に示すように、貫通部 102 の形状、特に、上面力も見た形状が切欠き 128の形状である点で異なる。切欠き 12 8の形状としては、図 52に示すように、多数の切欠き 128が連続して形成されたくし 歯状の切欠き 130が好ましい。この場合、貫通部 102を通じて放出される電子の放 出分布のばらつきを低減し、効率よく電子を放出する上で有利となる。特に、切欠き 1 28の平均幅を、 0. 以上、 10 m以下とすることが好ましい。この平均幅は、切 欠き 128の中心線を直交するそれぞれ異なる複数の線分の長さの平均を示す。 First, as shown in FIG. 52, the electron-emitting device 12Ba according to the first modification is different in that the shape of the penetrating portion 102, particularly the shape in view of the upper surface force, is the shape of the notch 128. As the shape of the notch 128, as shown in FIG. 52, a comb-shaped notch 130 in which a large number of notches 128 are continuously formed is preferable. In this case, it is advantageous in reducing variation in the emission distribution of electrons emitted through the through-hole 102 and efficiently emitting electrons. Notch 1 in particular The average width of 28 is preferably not less than 0 and not more than 10 m. This average width indicates the average length of a plurality of different line segments orthogonal to the center line of the notch 128.
[0220] 第 2の変形例に係る電子放出素子 12Bbは、図 53に示すように、貫通部 102の形 状、特に、上面から見た形状がスリット 132である点で異なる。ここで、スリット 132とは 、長軸方向（長手方向）の長さが短軸方向（短手方向）の長さの 10倍以上であるもの を 、う。従って、長軸方向（長手方向）の長さが短軸方向（短手方向）の長さの 10倍 未満のものは孔 114 (図 40参照）の形状として定義することができる。また、スリット 13 2としては、複数の孔 114が連通してつながつたものも含まれる。この場合、スリット 13 2の平均幅は、 0. 以上、 10 m以下とすることが好ましい。貫通部 102を通じ て放出される電子の放出分布のばらつきを低減し、効率よく電子を放出する上で有 利になる力もである。この平均幅は、スリット 132の中心線を直交するそれぞれ異なる 複数の線分の長さの平均を示す。  [0220] As shown in FIG. 53, the electron-emitting device 12Bb according to the second modification is different in that the shape of the penetrating portion 102, particularly, the shape seen from the top surface is the slit 132. Here, the slit 132 is a slit whose length in the major axis direction (longitudinal direction) is 10 times or more of the length in the minor axis direction (short direction). Accordingly, a shape whose length in the major axis direction (longitudinal direction) is less than 10 times the length in the minor axis direction (short direction) can be defined as the shape of the hole 114 (see FIG. 40). In addition, the slit 132 includes a plurality of holes 114 connected to each other. In this case, the average width of the slit 132 is preferably not less than 0 and not more than 10 m. It also has the advantage of reducing the variation in the emission distribution of electrons emitted through the through-hole 102 and efficiently emitting electrons. This average width indicates the average length of a plurality of different line segments orthogonal to the center line of the slit 132.
[0221] 第 3の変形例に係る電子放出素子 12Bcは、図 54に示すように、ェミッタ部 22の上 面のうち、貫通部 102と対応する部分、例えば誘電体の粒界の凹部 106にフローティ ング電極 134が存在している点で異なる。この場合、フローティング電極 134も電子 供給源となることから、電子の放出段階 (上述した第 1の電子放出方式における第 2 の出力期間 T2 (図 43参照））において、多数の電子を貫通部 102を通じて外部に放 出させることができる。この場合、フローティング電極 134からの電子放出は、フロー ティング電極 134Z誘電体 Ζ真空のトリプルジャンクションにおける電界集中によるも のが考えられる。  As shown in FIG. 54, the electron-emitting device 12Bc according to the third modified example has a portion corresponding to the penetrating portion 102 on the upper surface of the emitter portion 22, for example, a concave portion 106 in a dielectric grain boundary. The difference is that a floating electrode 134 is present. In this case, since the floating electrode 134 is also an electron supply source, in the electron emission stage (the second output period T2 in the first electron emission method described above (see FIG. 43)), a large number of electrons are allowed to pass through the through-hole 102. It can be released to the outside. In this case, electron emission from the floating electrode 134 may be due to electric field concentration in the triple junction of the floating electrode 134Z dielectric and vacuum.
[0222] ここで、第 2の実施の形態に係る光源 10Bの電子放出素子 12Bの特性、特に、電 圧 電荷量特性 (電圧一分極量特性）につ!ヽて説明する。  Here, the characteristics of the electron-emitting device 12B of the light source 10B according to the second embodiment, in particular, the voltage charge amount characteristic (voltage unipolarization amount characteristic) will be described.
[0223] この電子放出素子 12Bは、真空中において、図 55の特性に示すように、基準電圧  [0223] This electron-emitting device 12B has a reference voltage in a vacuum as shown in the characteristics of FIG.
=0 (V)を基準とした非対称のヒステリシス曲線を描く。  = 0 Draw an asymmetric hysteresis curve based on (V).
[0224] この特性について説明すると、先ず、ェミッタ部 22のうち、電子が放出される部分を 電子放出部と定義したとき、基準電圧が印加されるポイント pi (初期状態)では、前記 電子放出部に電子がほとんど蓄積されていない状態となっている。その後、負電圧を 印加すると、前記電子放出部において、ェミッタ部 22が分極反転した双極子の正電 荷の量が増し、それに伴って、第 1段階における上部電極 18から電子放出部へ向け た電子放出が起きて、電子が蓄積されていくこととなる。負電圧のレベルを負方向に 大きくしていくと、前記電子放出部への電子の蓄積に伴って、ある負電圧のポイント p 2において正電荷の量と負電荷の量が平衡な状態となり、負電圧のレベルを負方向 に大きくしていくと、さらに電子の蓄積量が増加し、これに伴って、負電荷の量が正電 荷の量よりも多い状態となる。ポイント p3において電子の蓄積飽和状態となる。ここで の負電荷の量は、蓄積したまま残っている電子の量と、ェミッタ部 22が分極反転した 双極子の負電荷の量の合計である。 [0224] This characteristic will be described. First, when the electron emitting portion of the emitter 22 is defined as an electron emitting portion, at the point pi (initial state) where a reference voltage is applied, the electron emitting portion is described. In this state, almost no electrons are accumulated. After that, when a negative voltage is applied, in the electron emission portion, the positive polarity of the dipole with the polarization reversed in the emitter portion 22 is obtained. As the amount of the load increases, electron emission from the upper electrode 18 to the electron emission portion in the first stage occurs, and electrons are accumulated. As the level of the negative voltage is increased in the negative direction, the amount of positive charge and the amount of negative charge become balanced at the point p 2 of a certain negative voltage as electrons accumulate in the electron emission portion, As the negative voltage level is increased in the negative direction, the amount of accumulated electrons further increases, and as a result, the amount of negative charge is greater than the amount of positive charge. At point p3, the accumulation of electrons becomes saturated. The amount of negative charge here is the sum of the amount of electrons remaining accumulated and the amount of negative charge of the dipole whose emitter 22 has undergone polarization inversion.
[0225] その後、負電圧のレベルを小さくしていき、さらに、基準電圧を超えて正電圧を印加 していくと、ポイント p4において、第 2段階における電子の放出が開始される。この正 電圧を正方向に大きくすれば、電子の放出量が増加し、ポイント p5では、正電荷の 量と負電荷の量が平衡な状態となる。そして、ポイント p6では、蓄積されていた電子 がほとんど放出され、正電荷の量と負電荷の量の差が初期状態とほぼ同じになる。 すなわち、電子の蓄積はほとんどなくなり、ェミッタ部 22が分極した双極子の負電荷 のみが電子放出部に現れている状態である。  [0225] Thereafter, when the level of the negative voltage is decreased and further a positive voltage is applied exceeding the reference voltage, emission of electrons in the second stage is started at point p4. If this positive voltage is increased in the positive direction, the amount of electron emission increases, and at point p5, the amount of positive charge and the amount of negative charge are balanced. At point p6, most of the accumulated electrons are released, and the difference between the amount of positive charge and the amount of negative charge is almost the same as in the initial state. That is, there is almost no accumulation of electrons, and only the negative charge of the dipole polarized in the emitter section 22 appears in the electron emission section.
[0226] そして、この特性の特徴ある部分は、以下の点である。  [0226] The characteristic part of this characteristic is as follows.
[0227] (1)正電荷の量と負電荷の量が平衡な状態であるポイント p2における負電圧を VI、 ポイント p5における正電圧を V2としたとき、  [0227] (1) When the negative voltage at point p2 where the amount of positive charge and the amount of negative charge are in equilibrium is VI, and the positive voltage at point p5 is V2,
I VI I < I V2 I  I VI I <I V2 I
である。  It is.
[0228] (2)より詳しくは、 1. 5 X I VI I < I V2 Iである。  [0228] (2) More specifically, 1.5 X I VI I <I V2 I.
[0229] (3)ポイント p2における正電荷の量と負電荷の量の変化の割合を Δ <3ΐΖ Δνΐ、ポ イント ρ5における正電荷の量と負電荷の量の変化の割合を A Q2Z AV2としたとき、  [0229] (3) The rate of change of the amount of positive charge and the amount of negative charge at point p2 is Δ <3ΐΖ Δνΐ, and the rate of change of the amount of positive charge and amount of negative charge at point ρ5 is A Q2Z AV2. When
( A Ql/ AVl) > ( A Q2/ AV2)  (A Ql / AVl)> (A Q2 / AV2)
である。  It is.
[0230] (4)電子が蓄積飽和状態となる電圧を V3、電子の放出が開始される電圧を V4とした とき、  [0230] (4) When V3 is the voltage at which electrons are accumulated and saturated, and V4 is the voltage at which electron emission starts,
1≤ I V4 I / I V3 I ≤1. 5 である。 1≤ I V4 I / I V3 I ≤1.5 It is.
[0231] 次に、図 55の特性を電圧一分極量特性の立場で説明する。初期状態において、ェ ミッタ部 22がー方向に分極されて、例えば双極子の負極がェミッタ部 22の上面に向 いた状態（図 56A参照）となっている場合を想定して説明する。  Next, the characteristic of FIG. 55 will be described from the standpoint of the voltage-one-polarization amount characteristic. In the initial state, the description will be made on the assumption that the emitter portion 22 is polarized in the negative direction so that, for example, the negative pole of the dipole faces the upper surface of the emitter portion 22 (see FIG. 56A).
[0232] 先ず、図 55に示すように、基準電圧 (例えば 0V)が印加されるポイント pi (初期状 態)では、図 56Aに示すように、双極子の負極がェミッタ部 22の上面に向いた状態と なって 、ることから、ェミッタ部 22の上面には電子がほとんど蓄積されて 、な 、状態と なっている。  First, as shown in FIG. 55, at a point pi (initial state) where a reference voltage (for example, 0 V) is applied, the negative pole of the dipole faces the upper surface of the emitter section 22 as shown in FIG. 56A. As a result, almost no electrons are accumulated on the upper surface of the emitter portion 22 and the state is in a state.
[0233] その後、負電圧を印加し、該負電圧のレベルを負方向に大きくしていくと、負の抗 電圧を超えたあたり（図 55のポイント p2参照）から分極が反転しはじめ、図 55のボイ ント p3にて全ての分極が反転することになる（図 56B参照)。この分極反転によって、 上記したトリプルジャンクションにおいて電界集中が発生し、第 1段階における上部電 極 18からェミッタ部 22に向けた電子放出が起こり、例えばェミッタ部 22のうち、上部 電極 18の貫通部 102から露出する部分や上部電極 18の周縁部近傍の部分に電子 が蓄積される（図 56C参照)。特に、上部電極 18から、ェミッタ部 22のうち、上部電極 18の貫通部 102から露出する部分に向けて電子が放出（内部放出）されることになる 。そして、図 55のポイント p3において電子の蓄積飽和状態となる。  [0233] After that, when a negative voltage is applied and the level of the negative voltage is increased in the negative direction, the polarization starts to reverse around the point where the negative coercive voltage is exceeded (see point p2 in Fig. 55). At 55 point p3, all polarizations are reversed (see Figure 56B). Due to this polarization inversion, electric field concentration occurs in the triple junction described above, and electron emission from the upper electrode 18 to the emitter part 22 occurs in the first stage. For example, in the emitter part 22, the penetrating part 102 of the upper electrode 18 Electrons are accumulated in the part exposed from the top and the part near the peripheral edge of the upper electrode 18 (see FIG. 56C). In particular, electrons are emitted (internally emitted) from the upper electrode 18 toward a portion of the emitter portion 22 exposed from the penetrating portion 102 of the upper electrode 18. Then, at point p3 in FIG. 55, the accumulated state of electrons is saturated.
[0234] その後、負電圧のレベルを小さくしていき、さらに、基準電圧を超えて正電圧を印加 していくと、ある電圧レベルまでは、ェミッタ部 22の上面の帯電状態が維持される（図 57A参照）。正電圧のレベルをさらに大きくいくと、図 55のポイント p4の直前におい て、双極子の負極がェミッタ部 22の上面に向き始める領域が発生し（図 57B参照）、 さらに、レベルを上げて図 55のポイント p4以降において、双極子の負極によるクーロ ン反発力により、電子の放出が開始される（図 57C参照)。この正電圧を正方向に大 きくすれば、電子の放出量が増加し、正の抗電圧を超えたあたり（ポイント p5)力 分 極が再び反転する領域が拡大して、ポイント P6では、蓄積されていた電子がほとんど 放出され、このときの分極量は初期状態の分極量とほぼ同じになる。 [0234] After that, when the level of the negative voltage is decreased and a positive voltage is applied exceeding the reference voltage, the charged state of the upper surface of the emitter section 22 is maintained up to a certain voltage level ( (See Figure 57A). When the level of the positive voltage is further increased, a region in which the negative pole of the dipole begins to face the upper surface of the emitter 22 immediately before the point p4 in FIG. 55 (see FIG. 57B). After point p4 of 55, electron emission starts due to the Coulomb repulsion by the negative pole of the dipole (see Fig. 57C). If large Kikusure the positive voltage in the positive direction, the amount of emitted electrons is increased, positive per exceeding the coercive voltage (the point p5) force component electrode is expanded region again inverted, the point P 6, Most of the accumulated electrons are released, and the amount of polarization at this time is almost the same as the amount of polarization in the initial state.
[0235] そして、この電子放出素子 12Bの特性の特徴ある部分は、以下の点となる。  [0235] Characteristic portions of the characteristics of the electron-emitting device 12B are as follows.
[0236] (A)負の抗電圧を vl、正の抗電圧を v2としたとき、 I vl I < I v2 I [0236] (A) When the negative coercive voltage is vl and the positive coercive voltage is v2, I vl I <I v2 I
である。  It is.
[0237] (B)より詳しくは、 1. 5 X I vl I < I v2 Iである。  [0237] (B) More specifically, 1.5 X I vl I <I v2 I.
[0238] (C)負の抗電圧 vlを印加した際における分極の変化の割合を A qlZ Avl、正の抗 電圧 v2を印加した際における分極の変化の割合を Δ q2Z Δ v2としたとき、  (C) When the rate of change in polarization when a negative coercive voltage vl is applied is A qlZ Avl, and the rate of change in polarization when a positive coercive voltage v2 is applied is Δ q2Z Δ v2,
( A ql/ Avl) > ( A q2/ Av2)  (A ql / Avl)> (A q2 / Av2)
である。  It is.
[0239] (D)電子が蓄積飽和状態となる電圧を v3、電子の放出が開始される電圧を v4とした とき、  [0239] (D) When the voltage at which electrons are accumulated and saturated is v3, and the voltage at which electron emission starts is v4,
1≤ I v4 I / I v3 I ≤1. 5  1≤ I v4 I / I v3 I ≤1.5
である。  It is.
[0240] この電子放出素子 12Bは、上述のような特性を有することから、複数の画素に応じ て配列された複数の電子放出素子 12Bを有し、各電子放出素子 12Bからの電子放 出によって発光を行う第 2の実施の形態に係る光源 10Bに簡単に適用させることが できる。  [0240] Since the electron-emitting device 12B has the above-described characteristics, the electron-emitting device 12B includes a plurality of electron-emitting devices 12B arranged according to a plurality of pixels, and emits electrons from each electron-emitting device 12B. The present invention can be easily applied to the light source 10B according to the second embodiment that emits light.
[0241] 次に、上述した電子放出素子 12Bを使用した構成された光源 10Bについて説明す る。  [0241] Next, a light source 10B configured using the above-described electron-emitting device 12B will be described.
[0242] この第 2の実施の形態に係る光源 10Bは、液晶ディスプレイ用のバックライト等の画 像表示を行うディスプレイに準拠した光源であって、図 58に示すように、多数の電子 放出素子 12Bが例えば画素等の発光素子に対応してマトリックス状あるいは千鳥状 に配列された発光部 14Bと、該発光部 14Bを駆動するための駆動回路 16Bとを有す る。この場合、 1発光素子当たり 1つの電子放出素子 12Bを割り当ててもよいし、 1発 光素子当たり複数の電子放出素子 12Bを割り当てるようにしてもよい。この実施の形 態では、説明を簡単にするために、 1発光素子当たり 1つの電子放出素子 12Bを割り 当てた場合を想定して説明する。  [0242] The light source 10B according to the second embodiment is a light source conforming to a display that displays an image such as a backlight for a liquid crystal display, and includes a large number of electron-emitting devices as shown in FIG. 12B includes, for example, light emitting units 14B arranged in a matrix or staggered manner corresponding to light emitting elements such as pixels, and a drive circuit 16B for driving the light emitting units 14B. In this case, one electron-emitting device 12B may be assigned to one light-emitting device, or a plurality of electron-emitting devices 12B may be assigned to one light-emitting device. In this embodiment, in order to simplify the description, the case where one electron-emitting device 12B is assigned to each light-emitting device will be described.
[0243] この駆動回路 16Bは、発光部 14Bに対して行を選択するための複数の行選択線 1 44が配線され、同じく発光部 14Bに対してデータ信号 Sdを供給するための複数の 信号線 146が配線されて ヽる。 [0244] さらに、この駆動回路 16Bは、行選択線 144に選択的に選択信号 Ssを供給して、 例えば 1行単位に電子放出素子 12Bを順次選択する行選択回路 148と、信号線 14 6にパラレルにデータ信号 Sdを出力して、行選択回路 148にて選択された行 (選択 行）にそれぞれデータ信号 Sdを供給する信号供給回路 150と、入力される制御信号 Sv (映像信号等)及び同期信号 Scに基づいて行選択回路 148及び信号供給回路 1 50を制御する信号制御回路 152とを有する。 [0243] The drive circuit 16B is provided with a plurality of row selection lines 144 for selecting a row for the light emitting unit 14B, and a plurality of signals for supplying the data signal Sd to the light emitting unit 14B. Wire 146 is wired. [0244] Further, the drive circuit 16B selectively supplies a selection signal Ss to the row selection line 144, for example, a row selection circuit 148 that sequentially selects the electron-emitting devices 12B in units of one row, and a signal line 14 6 The signal supply circuit 150 that outputs the data signal Sd in parallel and supplies the data signal Sd to the row selected by the row selection circuit 148 (selected row), and the input control signal Sv (video signal, etc.) And a signal control circuit 152 for controlling the row selection circuit 148 and the signal supply circuit 150 based on the synchronization signal Sc.
[0245] 行選択回路 148及び信号供給回路 150には電源回路 154 (例えば 50V及び OV) が接続され、特に、行選択回路 148と電源回路 154間の負極ラインと GND (グランド )間にパルス電源 156が接続されている。パルス電源 156は、後述する電荷蓄積期 間 Tdに基準電圧 (例えば OV)、発光期間 Thに電圧 (例えば 400V)とされたパルス 状の電圧波形を出力する。  [0245] A power supply circuit 154 (for example, 50 V and OV) is connected to the row selection circuit 148 and the signal supply circuit 150, and in particular, a pulse power supply is connected between the negative line between the row selection circuit 148 and the power supply circuit 154 and GND (ground). 156 is connected. The pulse power source 156 outputs a pulsed voltage waveform having a reference voltage (for example, OV) in a charge accumulation period Td, which will be described later, and a voltage (for example, 400 V) in the light emission period Th.
[0246] 行選択回路 148は、電荷蓄積期間 Tdに、選択行に対して選択信号 Ssを出力し、 非選択行に対して非選択信号 Snを出力する。また、行選択回路 148は、発光期間 T hに電源回路 154からの電源電圧（例えば 50V)とパルス電源 156からの電圧（例え ば- 400V)が加わった一定電圧（例えば- 350V)を出力する。  [0246] In the charge accumulation period Td, the row selection circuit 148 outputs the selection signal Ss to the selected row and outputs the non-selection signal Sn to the non-selected row. In addition, the row selection circuit 148 outputs a constant voltage (for example, −350 V) in which the power supply voltage (for example, 50 V) from the power supply circuit 154 and the voltage from the pulse power supply 156 (for example, −400 V) are added during the light emission period Th. .
[0247] 信号供給回路 150は、パルス生成回路 158と振幅変調回路 160とを有する。パル ス生成回路 158は、電荷蓄積期間 Tdにおいて、一定のパルス周期で一定の振幅（ 例えば 50V)を有するパルス信号 Spを生成、出力し、発光期間 Thにおいて、基準電 圧 (例えば 0V)を出力する。  [0247] The signal supply circuit 150 includes a pulse generation circuit 158 and an amplitude modulation circuit 160. The pulse generation circuit 158 generates and outputs a pulse signal Sp having a constant pulse period and a constant amplitude (for example, 50 V) in the charge accumulation period Td, and outputs a reference voltage (for example, 0 V) in the light emission period Th. To do.
[0248] 振幅変調回路 160は、電荷蓄積期間 Tdにおいて、ノ ルス生成回路 158からのパ ルス信号 Spをそれぞれ選択行に関する発光素子の輝度レベルに応じて振幅変調し 、それぞれ選択行に関する発光素子のデータ信号 Sdとして出力し、発光期間 Thに おいて、パルス生成回路 158からの基準電圧をそのまま出力する。これらのタイミン グ制御並びに選択された複数の発光素子の輝度レベルの振幅変調回路 160への供 給は、信号供給回路 150を通じて行われる。  [0248] In the charge accumulation period Td, the amplitude modulation circuit 160 modulates the amplitude of the pulse signal Sp from the pulse generation circuit 158 according to the luminance level of the light emitting element related to the selected row, and each of the light emitting element related to the selected row. The data signal Sd is output, and the reference voltage from the pulse generation circuit 158 is output as it is during the light emission period Th. The timing control and the supply of the luminance levels of the selected light emitting elements to the amplitude modulation circuit 160 are performed through the signal supply circuit 150.
[0249] 例えば図 59A—図 59Cにおいて 3つの例を示すように、輝度レベルが低い場合は 、パルス信号 Spの振幅を低レベル Vslとし（図 59A参照）、輝度レベルが中位の場合 は、パルス信号 Spの振幅を中レベル Vsmとし（図 59B参照）、輝度レベルが高い場 合は、パルス信号 Spの振幅を高レベル Vshとする（図 59C参照）。この例では、 3つ に分けた例を示したが、光源 10Bに適用する場合には、パルス信号 Spを、発光素子 の輝度レベルに応じて、例えば 128段階や 256段階に振幅変調される。 [0249] For example, as shown in three examples in FIGS. 59A to 59C, when the luminance level is low, the amplitude of the pulse signal Sp is set to the low level Vsl (see FIG. 59A), and when the luminance level is medium, When the amplitude of the pulse signal Sp is medium level Vsm (see Figure 59B) and the luminance level is high In this case, the amplitude of the pulse signal Sp is set to the high level Vsh (see Fig. 59C). In this example, three examples are shown, but when applied to the light source 10B, the pulse signal Sp is amplitude-modulated, for example, in 128 steps or 256 steps depending on the luminance level of the light emitting element.
[0250] ここで、信号供給回路 150の変形例について図 60—図 61Cを参照しながら説明す る。 Here, a modified example of the signal supply circuit 150 will be described with reference to FIGS. 60 to 61C.
[0251] 変形例に係る信号供給回路 150aは、図 60に示すように、パルス生成回路 162とパ ルス幅変調回路 164とを有する。パルス生成回路 162は、電荷蓄積期間 Tdにおい て、電子放出素子 12Bに印加される電圧波形（図 61A—図 61Cにおいて実線で示 す）において、立ち上がり部分の波形が連続的にレベルが変化するパルス信号 Spa ( 図 61A—図 61Cにおいて破線で示す)を生成、出力し、発光期間 Thにおいて、基 準電圧を出力する。そして、パルス幅変調回路 164は、電荷蓄積期間 Tdにおいて、 パルス生成回路 162からのパルス信号 Spaのパルス幅 Wp (図 61A—図 61C参照） をそれぞれ選択行に関する発光素子の輝度レベルに応じて変調し、それぞれ選択 行に関する発光素子のデータ信号 Sdとして出力する。発光期間 Thにおいてはパル ス生成回路 162からの基準電圧をそのまま出力する。この場合も、これらのタイミング 制御並びに選択された複数の発光素子の輝度レベルのパルス幅変調回路 164への 供給は、信号供給回路 150aを通じて行われる。  [0251] The signal supply circuit 150a according to the modification includes a pulse generation circuit 162 and a pulse width modulation circuit 164 as shown in FIG. The pulse generator 162 is a pulse whose voltage rises continuously in the voltage waveform applied to the electron-emitting device 12B (shown by a solid line in FIGS. 61A to 61C) during the charge accumulation period Td. Generates and outputs the signal Spa (indicated by a broken line in FIGS. 61A and 61C), and outputs a reference voltage during the light emission period Th. In the charge accumulation period Td, the pulse width modulation circuit 164 modulates the pulse width Wp (see FIGS. 61A to 61C) of the pulse signal Spa from the pulse generation circuit 162 according to the luminance level of the light emitting element for the selected row. The data signal Sd of the light emitting element for each selected row is output. In the light emission period Th, the reference voltage from the pulse generation circuit 162 is output as it is. Also in this case, the timing control and the supply of the luminance levels of the selected light emitting elements to the pulse width modulation circuit 164 are performed through the signal supply circuit 150a.
[0252] 例えば図 61A—図 61Cにおいて 3つの例を示すように、輝度レベルが低い場合は 、パルス信号 Spaのパルス幅 Wpを短くして、実質的な振幅を低レベル Vslとし（図 61 A参照）、輝度レベルが中位の場合は、パルス信号 Spaのパルス幅 Wpを中位の長さ にして、実質的な振幅を中位レベル Vsmとし（図 61B参照）、輝度レベルが高い場合 は、パルス信号 Spaのパルス幅 Wpを長くして、実質的な振幅を高レベル Vshとする（ 図 61C参照）。ここでは、 3つの例を示したが、光源 10Bに適用する場合には、パル ス信号 Spaを、発光素子の輝度レベルに応じて、例えば 128段階や 256段階にノ ル ス幅変調される。  [0252] For example, as shown in three examples in FIGS. 61A to 61C, when the luminance level is low, the pulse width Wp of the pulse signal Spa is shortened and the substantial amplitude is set to the low level Vsl (FIG. 61A). If the brightness level is medium, the pulse width Wp of the pulse signal Spa is set to the medium length, the actual amplitude is set to the medium level Vsm (see Fig. 61B), and the brightness level is high. Then, the pulse width Wp of the pulse signal Spa is lengthened and the substantial amplitude is set to the high level Vsh (see Fig. 61C). Here, three examples are shown, but when applied to the light source 10B, the pulse width of the pulse signal Spa is modulated in 128 steps or 256 steps, for example, depending on the luminance level of the light emitting element.
[0253] ここで、上述した電子の蓄積に係る負電圧のレベルを変化させた場合の特性図の 変化を、図 59A—図 59Cに示すパルス信号 Spに対する 3つの振幅変調の例と、図 6 1 A—図 61 Cに示すパルス信号 Spaに対する 3つのパルス幅変調の例との関連でみ ると、図 59A及び図 61Aに示す負電圧のレベル Vslでは、図 62Aに示すように、電 子放出素子 12Bに蓄積される電子の量が少ない。図 59B及び図 61Bに示す負電圧 のレベル Vsmでは、図 62Bに示すように、蓄積される電子の量が中位であり、図 59C 及び図 61Cに示す負電圧のレベル Vshでは、図 62Cに示すように、蓄積される電子 の量が多ぐほぼ飽和状態となっている。 [0253] Here, changes in the characteristic diagram when the level of the negative voltage related to the above-described electron accumulation is changed are shown in Fig. 59A to Fig. 59C as examples of three amplitude modulations for the pulse signal Sp shown in Figs. 1 A—in relation to the three pulse width modulation examples for the pulse signal Spa shown in Figure 61C. Then, at the negative voltage level Vsl shown in FIGS. 59A and 61A, as shown in FIG. 62A, the amount of electrons accumulated in the electron-emitting device 12B is small. At the negative voltage level Vsm shown in FIGS. 59B and 61B, the amount of accumulated electrons is moderate as shown in FIG.62B, and at the negative voltage level Vsh shown in FIGS.59C and 61C, it is shown in FIG. As shown, the amount of accumulated electrons is large and almost saturated.
[0254] し力し、これら図 62A—図 62Cに示すように、電子の放出が開始されるポイント p4 の電圧レベルはほとんど同じになっている。すなわち、電子を蓄積した後、ポイント p4 に示す電圧レベルまで印加電圧が変化したとしても、電子の蓄積量にほとんど変化 はなぐメモリ効果が発揮されることがわかる。  [0254] As shown in FIGS. 62A to 62C, the voltage level at the point p4 at which the electron emission starts is almost the same. In other words, even after the electrons are accumulated, even if the applied voltage changes up to the voltage level shown at point p4, it can be seen that a memory effect is exhibited in which there is almost no change in the amount of accumulated electrons.
[0255] また、この電子放出素子 12Bを光源 10Bの発光素子として利用する場合は、図 63 に示すように、上部電極 18の上方に、例えばガラスやアクリル製の透明板 166が配 置され、該透明板 166の裏面 (上部電極 18と対向する面）に例えば透明電極にて構 成されたコレクタ電極 168が配置され、該コレクタ電極 168には蛍光体 170が塗布さ れる。なお、コレクタ電極 168にはバイアス電圧源 172 (コレクタ電圧 Vc)が抵抗を介 して接続される。また、電子放出素子 12Bは、当然のことながら、真空空間内に配置 される。雰囲気中の真空度は、 102— 10— 6Paが好ましぐより好ましくは 10— 3— 10— 5Pa である。 [0255] When this electron-emitting device 12B is used as a light-emitting device of the light source 10B, as shown in FIG. 63, a transparent plate 166 made of, for example, glass or acrylic is disposed above the upper electrode 18, A collector electrode 168 made of, for example, a transparent electrode is disposed on the back surface (the surface facing the upper electrode 18) of the transparent plate 166, and a phosphor 170 is applied to the collector electrode 168. A bias voltage source 172 (collector voltage Vc) is connected to the collector electrode 168 via a resistor. The electron emitter 12B is naturally disposed in the vacuum space. The degree of vacuum in the atmosphere is preferably 10 2 − 10− 6 Pa, more preferably 10 − 3 − 10− 5 Pa.
[0256] このような範囲を選んだ理由は、低真空では、（1)空間内に気体分子が多いため、 プラズマを生成し易ぐプラズマが多量に発生され過ぎると、その正イオンが多量に 上部電極 18に衝突して損傷を進めるおそれや、（2)放出電子がコレクタ電極 168に 到達する前に気体分子に衝突してしま 、、コレクタ電圧 Vcで十分に加速した電子に よる蛍光体 170の励起が十分に行われなくなるおそれがあるからである。  [0256] The reason for choosing such a range is that, in a low vacuum, (1) because there are many gas molecules in the space, if too much plasma is generated that is easy to generate plasma, a large amount of positive ions There is a risk of colliding with the upper electrode 18 to promote damage, and (2) phosphors due to electrons accelerated sufficiently by the collector voltage Vc when the emitted electrons collide with gas molecules before reaching the collector electrode 168. This is because there is a possibility that the excitation of is not performed sufficiently.
[0257] 一方、高真空では、電界が集中するポイントから電子を放出し易いものの、構造体 の支持、及び真空のシール部が大きくなり、小型化に不利になるという問題があるか らである。  [0257] On the other hand, in a high vacuum, electrons are likely to be emitted from the point where the electric field concentrates, but there is a problem in that the structure support and the vacuum seal portion become large, which is disadvantageous for miniaturization. .
[0258] 図 63の例では、透明板 166の裏面にコレクタ電極 168を形成し、該コレクタ電極 16 8の表面（上部電極 18と対向する面）に蛍光体 170を形成するようにした力 その他、 図 64に示すように、透明板 166の裏面に蛍光体 170を形成し、該蛍光体 170を覆う ようにコレクタ電極 168を形成するようにしてもよ!、。 In the example of FIG. 63, the force is such that the collector electrode 168 is formed on the back surface of the transparent plate 166, and the phosphor 170 is formed on the surface of the collector electrode 168 (the surface facing the upper electrode 18). 64, a phosphor 170 is formed on the back surface of the transparent plate 166, and the phosphor 170 is covered. So that the collector electrode 168 may be formed!
[0259] これは、 CRT等で用いられる構成であって、コレクタ電極 168がメタルバックとして 機能する。ェミッタ部 22から放出された電子はコレクタ電極 168を貫通して蛍光体 17 0に進入し、該蛍光体 170を励起する。従って、コレクタ電極 168は電子が貫通でき る程度の厚さであり、 lOOnm以下が好ましい。電子の運動エネルギーが大きいほど 、コレクタ電極 168の厚みを厚くすることができる。  [0259] This is a configuration used in a CRT or the like, and the collector electrode 168 functions as a metal back. Electrons emitted from the emitter 22 pass through the collector electrode 168 and enter the phosphor 170 to excite the phosphor 170. Therefore, the collector electrode 168 is thick enough to allow electrons to pass through, and is preferably less than lOOnm. The greater the kinetic energy of the electrons, the thicker the collector electrode 168 can be.
[0260] このような構成とすることで以下の効果を奏することができる。  [0260] With such a configuration, the following effects can be obtained.
[0261] (a)蛍光体 170が導電性でない場合、蛍光体 170の帯電 (負）を防ぎ、電子の加速 電界を維持することができる。  [0261] (a) When phosphor 170 is not conductive, charging (negative) of phosphor 170 can be prevented, and an accelerating electric field of electrons can be maintained.
[0262] (b)コレクタ電極 168が蛍光体 170の発光を反射して、蛍光体 170の発光を効率よく 透明板 166側 (発光面側）に放出することができる。  (B) The collector electrode 168 reflects the light emitted from the phosphor 170, and the light emitted from the phosphor 170 can be efficiently emitted to the transparent plate 166 side (light emitting surface side).
[0263] (c)蛍光体 170への過度な電子の衝突を防ぐことができ、蛍光体 170の劣化や蛍光 体 170からのガス発生を防止することができる。  (C) Excessive collision of electrons with the phosphor 170 can be prevented, and deterioration of the phosphor 170 and generation of gas from the phosphor 170 can be prevented.
[0264] 次に、この第 2の実施の形態に係る光源 10Bに用いられる電子放出素子 12Bにつ V、ての 4つの実験例 (第 1一第 4の実験例）を示す。  Next, four experimental examples (first, first, and fourth experimental examples) for the electron-emitting device 12B used in the light source 10B according to the second embodiment are shown.
[0265] 第 1の実験例は、電子放出素子 12Bの電子の放出状態をみたものである。すなわ ち、図 65Aに示すように、電子放出素子 12Bに対して 70Vの電圧を有する書込み パルス Pwを印加して、電子放出素子 12Bに電子を蓄積させ、その後、 280Vの電圧 を有する点灯パルス Phを印加して電子を放出させた。電子の放出状態は、蛍光体 1 70の発光を受光素子 (フォトダイオード）にて検出して測定した。検出波形を図 65B に示す。なお、書込みパルス Pwと点灯パルス Phのデューティ比は 50%とした。  [0265] In the first experimental example, the electron emission state of the electron-emitting device 12B is observed. That is, as shown in FIG. 65A, a write pulse Pw having a voltage of 70V is applied to the electron-emitting device 12B to accumulate electrons in the electron-emitting device 12B, and then a lighting pulse having a voltage of 280V. Ph was applied to emit electrons. The electron emission state was measured by detecting the light emission of the phosphor 170 with a light receiving element (photodiode). The detected waveform is shown in Figure 65B. The duty ratio of the write pulse Pw and the lighting pulse Ph was 50%.
[0266] この第 1の実験例から、点灯パルス Phの立ち上がり途中から発光が開始され、該点 灯パルス Phの初期段階で発光が終了していることがわかる。従って、点灯パルス Ph の期間をより短くしても発光には影響はないものと考えられる。これは、高電圧の印加 期間の短縮ィ匕につながり、消費電力の低減ィ匕を図る上で有利になる。  [0266] From this first experimental example, it can be seen that light emission started in the middle of the rise of the lighting pulse Ph, and light emission ended at the initial stage of the lighting pulse Ph. Therefore, it is considered that light emission is not affected even if the lighting pulse Ph is shortened. This leads to a shortening of the high voltage application period, which is advantageous in reducing the power consumption.
[0267] 第 2の実験例は、電子放出素子 12Bの電子の放出量が、図 66に示す書込みパル ス Pwの振幅によってどのように変化するかをみたものである。電子の放出量の変化 は第 1の実験例と同様に、蛍光体 170の発光を受光素子 (フォトダイオード）にて検出 して測定した。実験結果を図 67に示す。 [0267] The second experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the amplitude of the write pulse Pw shown in FIG. The change in the amount of emitted electrons is detected by the light receiving element (photodiode) as in the first experimental example. And measured. The experimental results are shown in FIG.
[0268] 図 67において、実線 Aは、点灯パルス Phの振幅を 200Vとし、書込みパルス Pwの 振幅を 10Vから 80Vに変化させた場合の特性を示し、実線 Bは、点灯パルス Ph の振幅を 350Vとし、書込みパルス Pwの振幅を 10Vから—80Vに変化させた場合 の特性を示す。 [0268] In Fig. 67, the solid line A shows the characteristics when the amplitude of the lighting pulse Ph is 200V and the amplitude of the write pulse Pw is changed from 10V to 80V, and the solid line B shows the amplitude of the lighting pulse Ph is 350V. The characteristics when the amplitude of the write pulse Pw is changed from 10V to –80V are shown.
[0269] この図 67に示すように、書込みパルス Pwを 20Vから 40Vに変化させた場合、 発光輝度は、ほとんど直線的に変化していることがわかる。特に、点灯パルス Phの振 幅が 350Vの場合と 200Vの場合とで比較すると、 350Vの場合が書込みパルス Pw に対する発光輝度変化のダイナミックレンジが広くなつており、発光輝度の向上を図 る上で有利であることがわかる。また、第 2の実施の形態に係る光源 10Bをディスプレ ィに適用した場合、該ディスプレイのコントラストの向上を図ることができる。この傾向 は、点灯パルス Phの振幅設定に対して発光輝度が飽和するまでの範囲にぉ 、て、 点灯パルス Phの振幅を上げるほど有利になると思われる力 信号伝送系の耐圧や 消費電力との関係で、最適な値に設定することが好ましい。  As shown in FIG. 67, when the write pulse Pw is changed from 20V to 40V, it can be seen that the light emission luminance changes almost linearly. In particular, when the amplitude of the lighting pulse Ph is 350 V and when it is 200 V, the dynamic range of the emission luminance change with respect to the write pulse Pw is wider in the case of 350 V. It turns out to be advantageous. Further, when the light source 10B according to the second embodiment is applied to a display, the contrast of the display can be improved. This tendency can be seen in the range until the light emission brightness is saturated with respect to the amplitude setting of the lighting pulse Ph, and the force that seems to be more advantageous as the amplitude of the lighting pulse Ph is increased. In view of this, it is preferable to set the optimum value.
[0270] 第 3の実験例は、電子放出素子 12Bの電子の放出量が、図 66に示す点灯パルス Phの振幅によってどのように変化するかをみたものである。電子の放出量の変化は 第 1の実験例と同様に、蛍光体 170の発光を受光素子 (フォトダイオード）にて検出し て測定した。実験結果を図 68に示す。  [0270] The third experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the amplitude of the lighting pulse Ph shown in Fig. 66. The change in the amount of emitted electrons was measured by detecting the light emission of phosphor 170 with a light receiving element (photodiode), as in the first experimental example. The experimental results are shown in FIG.
[0271] 図 68において、実線 Cは、書込みパルス Pwの振幅を 40Vとし、点灯パルス Phの 振幅を 50Vカゝら 400Vに変化させた場合の特性を示し、実線 Dは、書込みパルス Pw の振幅を 70Vとし、点灯パルス Phの振幅を 50Vから 400Vに変化させた場合の特 性を示す。  In FIG. 68, the solid line C shows the characteristics when the amplitude of the write pulse Pw is 40 V and the amplitude of the lighting pulse Ph is changed from 50 V to 400 V, and the solid line D is the amplitude of the write pulse Pw. Shows the characteristics when the lighting pulse Ph amplitude is changed from 50V to 400V.
[0272] この図 68に示すように、点灯パルス Phを 100Vから 300Vに変化させた場合、発光 輝度は、ほとんど直線的に変化していることがわかる。特に、書込みパルス Pwの振 幅が 40Vの場合と 70Vの場合とで比較すると、 70Vの場合が点灯パルス Phに 対する発光輝度変化のダイナミックレンジが広くなつており、発光輝度の向上、並び にディスプレイに適用した場合のコントラストの向上を図る上で有利であることがわか る。この傾向は、書込みパルス Pwの振幅設定に対して発光輝度が飽和するまでの 範囲において、書込みパルス Pwの振幅 (この場合、絶対値)を上げるほど有利にな ると思われるが、この場合も、信号伝送系の耐圧や消費電力との関係で、最適な値 に設定することが好ましい。 As shown in FIG. 68, when the lighting pulse Ph is changed from 100 V to 300 V, it can be seen that the emission luminance changes almost linearly. In particular, when the amplitude of the write pulse Pw is 40V and 70V, the dynamic range of the emission luminance change with respect to the lighting pulse Ph is wider in the case of 70V. It can be seen that it is advantageous in improving the contrast when applied to the above. This tendency is observed until the emission brightness is saturated with respect to the amplitude setting of the write pulse Pw. In the range, it seems that it is more advantageous to increase the amplitude (in this case, absolute value) of the write pulse Pw, but in this case as well, it is set to the optimum value in relation to the withstand voltage and power consumption of the signal transmission system. It is preferable.
[0273] 第 4の実験例は、電子放出素子 12Bの電子の放出量が、図 63又は図 64に示すコ レクタ電圧 Vcのレベルによってどのように変化するかをみたものである。電子の放出 量の変化は第 1の実験例と同様に、蛍光体 170の発光を受光素子 (フォトダイオード )にて検出して測定した。実験結果を図 69に示す。  [0273] The fourth experimental example shows how the amount of electrons emitted from the electron-emitting device 12B varies depending on the level of the collector voltage Vc shown in Fig. 63 or Fig. 64. The change in the amount of emitted electrons was measured by detecting the light emission of the phosphor 170 with a light receiving element (photodiode), as in the first experimental example. Figure 69 shows the experimental results.
[0274] 図 69において、実線 Eは、コレクタ電圧 Vcのレベルを 3kVとし、点灯パルス Phの振 幅を 80Vから 500Vに変化させた場合の特性を示し、実線 Fは、コレクタ電圧 Vcのレ ベルを 7kVとし、点灯パルス Phの振幅を 80Vから 500Vに変化させた場合の特性を 示す。  [0274] In Fig. 69, solid line E shows the characteristics when the level of collector voltage Vc is 3 kV and the amplitude of lighting pulse Ph is changed from 80 V to 500 V, and solid line F is the level of collector voltage Vc. The characteristics when the amplitude of the lighting pulse Ph is changed from 80V to 500V are shown.
[0275] この図 69に示すように、コレクタ電圧 Vcを 7kVとした方力 3kVの場合よりも、点灯 パルス Phに対する発光輝度変化のダイナミックレンジが広くなつており、発光輝度の 向上、並びにディスプレイに適用した場合のコントラストの向上を図る上で有利である ことがわかる。この傾向は、コレクタ電圧 Vcのレベルを上げるほど有利になると思わ れるが、この場合も、信号伝送系の耐圧や消費電力との関係で、最適な値に設定す ることが好ましい。  [0275] As shown in Fig. 69, the dynamic range of the emission luminance change with respect to the lighting pulse Ph is wider than when the collector voltage Vc is 7 kV and the force is 3 kV. It can be seen that it is advantageous in improving the contrast when applied. This tendency seems to be more advantageous as the level of the collector voltage Vc increases, but in this case as well, it is preferable to set the optimum value in relation to the withstand voltage and power consumption of the signal transmission system.
[0276] ここで、上述した第 2の実施の形態に係る光源 10Bの 1つの駆動方法について図 7 0及び図 71を参照しながら説明する。図 70は、代表的に 1行 1列、 2行 1列及び n行 1 列の画素の動作を示す。なお、ここで使用する電子放出素子 12Bは、図 55のポイン ト p2における抗電圧 vlが例えば 20V、ポイント p5における抗電圧 v2が + 70V、ポ イント p3における電圧 v3が— 50V、ポイント p4における電圧 v4が + 50Vの特性を有 する。  Here, one driving method of the light source 10B according to the second embodiment described above will be described with reference to FIG. 70 and FIG. FIG. 70 typically shows the operation of pixels in 1 row and 1 column, 2 rows and 1 column, and n rows and 1 column. The electron-emitting device 12B used here has a coercive voltage vl at point p2 in FIG. 55 of, for example, 20 V, a coercive voltage v2 at point p5 of +70 V, a voltage v3 at point p3 of −50 V, and a voltage at point p4. v4 has the characteristic of + 50V.
[0277] また、図 70に示すように、全部の行を選択する期間を 1フレームとしたとき、該 1フレ ーム内に 1つの電荷蓄積期間 Tdと 1つの発光期間 Thが含まれており、 1つの電荷蓄 積期間 Tdには、 n個の選択期間 Tsが含まれる。各選択期間 Tsはそれぞれ対応する 行の選択期間 Tsとなるため、対応しな!、n-l個の行にっ ヽては非選択期間 Tnとな る。 [0278] そして、この駆動方法は、電荷蓄積期間 Tdに、全ての電子放出素子 12Bを走査し て、 ON対象 (発光対象)の画素に対応した複数の電子放出素子 12Bにそれぞれ対 応する発光素子の輝度レベルに応じた電圧を印加することにより、 ON対象の発光素 子に対応した複数の電子放出素子 12Bにそれぞれ対応する発光素子の輝度レベル に応じた量の電荷 (電子)を蓄積させ、次の発光期間 Thに、全ての電子放出素子 12 Bに一定の電圧を印加して、 ON対象の発光素子に対応した複数の電子放出素子 1 2Bカゝらそれぞれ対応する発光素子の輝度レベルに応じた量の電子を放出させて、 ON対象の発光素子を発光させると ヽぅものである。 Further, as shown in FIG. 70, when the period for selecting all the rows is one frame, one charge accumulation period Td and one light emission period Th are included in the one frame. One charge accumulation period Td includes n selection periods Ts. Since each selection period Ts is the selection period Ts of the corresponding row, it does not correspond !, and nl rows are the non-selection period Tn. [0278] Then, in this driving method, all the electron-emitting devices 12B are scanned during the charge accumulation period Td, and light emission corresponding to each of the plurality of electron-emitting devices 12B corresponding to the ON target (light-emitting target) pixels is performed. By applying a voltage according to the luminance level of the element, an amount of electric charges (electrons) corresponding to the luminance level of the light emitting element corresponding to each of the plurality of electron emitting elements 12B corresponding to the light emitting element to be turned on is accumulated. In the next light-emitting period Th, a plurality of electron-emitting devices corresponding to the light-emitting devices to be turned on by applying a constant voltage to all the electron-emitting devices 12 B 1 2B brightness levels of the corresponding light-emitting devices The amount of electrons corresponding to the amount of emitted light is emitted, and the light emitting element to be turned on emits light.
[0279] 具体的に説明すると、図 71にも示すように、先ず、 1行目の選択期間 Tsにおいては 、 1行目の行選択線 144に例えば 50Vの選択信号 Ssが供給され、その他の行の行 選択線 144に例えば 0Vの非選択信号 Snが供給される。 1列目の発光素子のうち、 ON (発光）とすべき発光素子の信号線 146に供給されるデータ信号 Sdの電圧は、 0 V以上、 30V以下の範囲であって、かつ、それぞれ対応する発光素子の輝度レベル に応じた電圧となる。輝度レベル最大であれば 0Vとなる。このデータ信号 Sdの輝度 レベルに応じた変調は、図 58に示す振幅変調回路 160や図 60に示すパルス幅変 調回路 164を通じて行われる。  Specifically, as shown in FIG. 71, first, in the selection period Ts of the first row, for example, a selection signal Ss of 50 V is supplied to the row selection line 144 of the first row, and the other For example, a non-selection signal Sn of 0 V is supplied to the row selection line 144 of the row. Among the light emitting elements in the first row, the voltage of the data signal Sd supplied to the signal line 146 of the light emitting element to be turned ON (light emission) is in the range of 0 V or more and 30 V or less, and corresponds to each. The voltage corresponds to the luminance level of the light emitting element. If the luminance level is maximum, it will be 0V. The modulation according to the luminance level of the data signal Sd is performed through the amplitude modulation circuit 160 shown in FIG. 58 and the pulse width modulation circuit 164 shown in FIG.
[0280] これにより、 1行目の ONとすべき各発光素子にそれぞれ対応する電子放出素子 1 2Bの上部電極 18と下部電極 20間にはそれぞれ輝度レベルに応じて—50V以上、 20V以下の電圧が印加される。その結果、上述した各電子放出素子 12Bには、印加 された電圧に応じた電子が蓄積されることになる。例えば 1行 1列目の発光素子に対 応する電子放出素子 12Bは、例えば最大輝度レベルであることから、図 55の特性の ポイント p3の状態となり、ェミッタ部 22のうち、上部電極 18の貫通部 102から露出す る部分に最大量の電子が蓄積されることになる。  [0280] Thus, between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to each light-emitting device to be turned ON in the first row, between -50V and 20V or less depending on the luminance level, respectively. A voltage is applied. As a result, electrons corresponding to the applied voltage are accumulated in each of the electron-emitting devices 12B described above. For example, since the electron-emitting device 12B corresponding to the light-emitting device in the first row and the first column has, for example, the maximum luminance level, the state becomes a point p3 in the characteristic of FIG. The maximum amount of electrons is accumulated in the portion exposed from the portion 102.
[0281] なお、 OFF (消光)を示す発光素子に対応する電子放出素子 12Bに供給されるデ ータ信号 Sdの電圧は、例えば 50Vであり、これにより、 OFF対象の発光素子に対応 する電子放出素子 12Bには 0Vが印加され、これは、図 55の特性のポイント piの状 態となり、電子の蓄積は行われない。  [0281] Note that the voltage of the data signal Sd supplied to the electron-emitting device 12B corresponding to the light-emitting device indicating OFF (quenching) is, for example, 50 V, and thus the electron corresponding to the light-emitting device to be turned off. 0V is applied to the emitting element 12B, which is in the state of the point pi in the characteristic of FIG. 55, and no electrons are stored.
[0282] 1行目へのデータ信号 Sdの供給が終了した後、 2行目の選択期間 Tsにおいては、 2行目の行選択線 144に 50Vの選択信号 Ssが供給され、その他の行の行選択線 14 4に OVの非選択信号 Snが供給される。この場合も、 ON (発光）とすべき発光素子に 対応する電子放出素子 12Bの上部電極 18と下部電極 20間にはそれぞれ輝度レべ ルに応じて 50V以上、 20V以下の電圧が印加される。このとき、非選択状態にあ る例えば 1行目の発光素子に対応する電子放出素子 12Bの上部電極 18と下部電極 20間には 0V以上、 50V以下の電圧が印加される力 この電圧は、図 55の特性のポ イント 4に達しないレベルの電圧であることから、 1行目のうち、 ON (発光）とすべき発 光素子に対応する電子放出素子 12Bから電子が放出されるということはない。つまり 、非選択状態の 1行目の発光素子が、選択状態の 2行目の画素に供給されるデータ 信号 Sdの影響を受けると 、うことがな 、。 [0282] After the supply of the data signal Sd to the first row is completed, in the selection period Ts of the second row, The 50V selection signal Ss is supplied to the row selection line 144 of the second row, and the OV non-selection signal Sn is supplied to the row selection line 144 of the other rows. Also in this case, a voltage of 50 V or more and 20 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to the light emitting device to be turned on (light emission) according to the luminance level. . At this time, for example, a voltage of 0 V or more and 50 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron emitting device 12B corresponding to the light emitting device in the first row in the non-selected state. Since the voltage does not reach point 4 in the characteristics of Fig. 55, electrons are emitted from the electron-emitting device 12B corresponding to the light-emitting device that should be turned on (emission) in the first row. There is no. In other words, when the light-emitting elements in the first row in the non-selected state are affected by the data signal Sd supplied to the pixels in the second row in the selected state, it is not possible.
[0283] 以下同様に、 n行目の選択期間 Tsにおいては、 n行目の行選択線 144に 50Vの選 択信号 Ssが供給され、その他の行の行選択線 144に 0Vの非選択信号 Snが供給さ れる。この場合も、 ON (発光）とすべき発光素子に対応する電子放出素子 12Bの上 部電極 18と下部電極 20間にはそれぞれ輝度レベルに応じて 50V以上、— 20V以 下の電圧が印加される。このとき、非選択状態にある 1行一 (n— 1)行の各発光素子 に対応する電子放出素子 12Bの上部電極 18と下部電極 20間には 0V以上、 50V以 下の電圧が印加されるが、これら非選択状態の各発光素子のうち、 ON (発光）とす べき発光素子に対応する電子放出素子 12Bから電子が放出されるということはない。  [0283] Similarly, in the selection period Ts of the n-th row, the 50V selection signal Ss is supplied to the row selection line 144 of the n-th row, and the 0V non-selection signal is supplied to the row selection line 144 of the other rows. Sn is supplied. Also in this case, a voltage of 50V or more and −20V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to the light emitting device to be turned ON (light emission) according to the luminance level. The At this time, a voltage of 0 V or more and 50 V or less is applied between the upper electrode 18 and the lower electrode 20 of the electron-emitting device 12B corresponding to each of the light-emitting elements in one row and one (n−1) row in the non-selected state. However, electrons are not emitted from the electron-emitting devices 12B corresponding to the light-emitting devices that should be turned ON (light-emitting) among the non-selected light-emitting devices.
[0284] n行目の選択期間 Tsが経過した段階で、発光期間 Thに入る。この発光期間 Thで は、全電子放出素子 12Bの上部電極 18には、信号供給回路 150を通じて基準電圧 (例えば 0V)が印加され、全電子放出素子 12Bの下部電極 20には、 350Vの電圧 (パルス電源 156の- 400V+行選択回路 148の電源電圧 50V)が印加される。これ により、全電子放出素子 12Bの上部電極 18と下部電極 20間に高電圧（ + 350V)が 印加される。全電子放出素子 12Bは、それぞれ図 55の特性のポイント p6の状態とな り、図 57Cに示すように、ェミッタ部 22のうち、前記電子の蓄積されていた部分から、 貫通部 102を通じて電子が放出される。もちろん、上部電極 18の外周部近傍からも 電子が放出される。  [0284] The light emission period Th starts when the selection period Ts of the n-th row has passed. In this light emission period Th, a reference voltage (for example, 0 V) is applied to the upper electrode 18 of the all-electron emission element 12B through the signal supply circuit 150, and a voltage (350 V) is applied to the lower electrode 20 of the all-electron emission element 12B. Pulse power supply 156-400V + row selection circuit 148 power supply voltage 50V) is applied. As a result, a high voltage (+350 V) is applied between the upper electrode 18 and the lower electrode 20 of the all-electron emitting device 12B. All the electron-emitting devices 12B are in the state of the characteristic point p6 in FIG. 55, and as shown in FIG. 57C, electrons are transmitted from the portion where the electrons are accumulated in the emitter portion 22 through the penetrating portion 102. Released. Of course, electrons are also emitted from the vicinity of the outer peripheral portion of the upper electrode 18.
[0285] つまり、 ON (発光）とすべき発光素子に対応する電子放出素子 12Bから電子が放 出され、放出された電子は、これら電子放出素子 12Bに対応するコレクタ電極 168に 導かれて、対応する蛍光体 170を励起し、発光する。この発光は、透明板 166の表 面を通じて外方に放射されることになる。 That is, electrons are emitted from the electron-emitting device 12B corresponding to the light-emitting device that should be turned ON (light emission). The emitted and emitted electrons are guided to the collector electrode 168 corresponding to these electron-emitting devices 12B, and the corresponding phosphor 170 is excited to emit light. This emitted light is emitted outward through the surface of the transparent plate 166.
[0286] 以後同様に、フレーム単位に、電荷蓄積期間 Tdにおいて、 ON (発光）とすべき発 光素子に対応する電子放出素子 12Bに電子を蓄積し、発光期間 Thにおいて、蓄積 されていた電子を放出して蛍光発光させることで、その発光が、透明板 166の表面を 通じて外方に放射されることになる。  [0286] Similarly, in the frame unit, electrons are accumulated in the electron-emitting device 12B corresponding to the light-emitting device to be turned ON (light emission) in the charge accumulation period Td, and the electrons accumulated in the light-emission period Th are stored. Is emitted to emit fluorescence, and the emitted light is emitted outward through the surface of the transparent plate 166.
[0287] このように、この第 2の実施の形態に係る光源 10Bにおいては、上述したように、 1フ レーム内の電荷蓄積期間 Tdに、全ての電子放出素子 12Bを走査して、 ON対象の 発光素子に対応した複数の電子放出素子 12Bにそれぞれ対応する発光素子の輝 度レベルに応じた電圧を印加することにより、 ON対象の発光素子に対応した複数の 電子放出素子 12Bにそれぞれ対応する発光素子の輝度レベルに応じた量の電荷を 蓄積させ、次の発光期間 Thに、全ての電子放出素子 12Bに一定の電圧を印加して 、 ON対象の発光素子に対応した複数の電子放出素子 12Bからそれぞれ対応する 発光素子の輝度レベルに応じた量の電子を放出させて、 ON対象の発光素子を発 光させることが可會となる。  [0287] Thus, in the light source 10B according to the second embodiment, as described above, all the electron-emitting devices 12B are scanned during the charge accumulation period Td in one frame to be turned on. By applying a voltage corresponding to the brightness level of the light emitting element corresponding to each of the plurality of electron emitting elements 12B corresponding to the light emitting element, each corresponding to the plurality of electron emitting elements 12B corresponding to the light emitting elements to be turned on. A plurality of electron-emitting devices corresponding to the light-emitting devices to be turned on by accumulating an amount of charge corresponding to the luminance level of the light-emitting device and applying a constant voltage to all the electron-emitting devices 12B in the next light-emitting period Th It becomes possible to emit an amount of electrons corresponding to the luminance level of the corresponding light emitting element from 12B to emit the light emitting element to be turned on.
[0288] また、この第 2の実施の形態の光源 10Bに使用される電子放出素子 12Bにおいて は、例えば電子が蓄積飽和状態となる電圧 V3と、電子の放出が開始される電圧 V4 との関係が、 i≤ I V4 I / I V3 I ≤1. 5である。  [0288] In addition, in the electron-emitting device 12B used in the light source 10B of the second embodiment, for example, the relationship between the voltage V3 at which electrons are accumulated and saturated and the voltage V4 at which electron emission is started However, i≤IV4I / IV3I≤1.5.
[0289] 通常、例えば、電子放出素子 12Bをマトリックス状に配列して、水平走査期間に同 期させて 1行単位に電子放出素子 12Bを選択し、選択状態にある電子放出素子 12 Bに対してそれぞれ発光素子の輝度レベルに応じたデータ信号 Sdを供給するとき、 非選択状態の発光素子にも、データ信号 Sdが供給されることになる。  [0289] Usually, for example, the electron-emitting devices 12B are arranged in a matrix, and the electron-emitting devices 12B are selected in units of one row in synchronization with the horizontal scanning period. Thus, when the data signal Sd corresponding to the luminance level of each light emitting element is supplied, the data signal Sd is also supplied to the non-selected light emitting elements.
[0290] 非選択状態の電子放出素子 12Bがデータ信号 Sdの影響を受けて例えば電子放 出してしまうと、光源 10Bの輝度ムラ等を招くという問題がある。  [0290] If the electron-emitting device 12B in the non-selected state is affected by the data signal Sd and emits, for example, electrons, there is a problem that luminance unevenness of the light source 10B is caused.
[0291] しかし、この電子放出素子 12Bでは、上述した特性を有するため、選択状態の電子 放出素子 12Bに供給されるデータ信号 Sdの電圧レベルを、基準電圧から電圧 V3ま での任意の電圧とし、非選択状態の電子放出素子 12Bに対して、例えばデータ信号 Sdの逆極性の信号が供給されるように設定するという簡単な電圧関係にしても、非 選択状態の発光素子が、選択状態の発光素子へのデータ信号 Sdによって影響を受 けることがない。すなわち、各発光素子の選択期間 Tsにおいて蓄積された各発光素 子の電子蓄積量 (各電子放出素子 12Bにおけるェミッタ部 22の帯電量）が、次の発 光期間 Thにおいて電子放出が行われるまで維持されることになり、その結果、各発 光素子でのメモリ効果を実現でき、高輝度、高コントラストイ匕を図ることができる。 However, since this electron-emitting device 12B has the characteristics described above, the voltage level of the data signal Sd supplied to the electron-emitting device 12B in the selected state is an arbitrary voltage from the reference voltage to the voltage V3. For example, a data signal for the non-selected electron-emitting device 12B Even with a simple voltage relationship in which a signal having a reverse polarity of Sd is supplied, the non-selected light emitting element is not affected by the data signal Sd to the selected light emitting element. That is, the electron accumulation amount of each light emitting element accumulated in the selection period Ts of each light emitting element (the amount of charge of the emitter 22 in each electron emitting element 12B) is equal to the amount of electrons emitted in the next light emitting period Th. As a result, the memory effect of each light emitting element can be realized, and high brightness and high contrast can be achieved.
[0292] 一方、この第 2の実施の形態に係る光源 10Bにおいては、電荷蓄積期間 Tdに、全 ての電子放出素子 12Bに必要な電荷を蓄積し、その後の発光期間 Thに、全ての電 子放出素子 12Bに対して電子放出に必要な電圧を印加して、 ON対象の発光素子 に対応した複数の電子放出素子 12Bから電子を放出させて、 ON対象の発光素子を 発光させるようにしている。  On the other hand, in the light source 10B according to the second embodiment, charges necessary for all the electron-emitting devices 12B are accumulated during the charge accumulation period Td, and all the electric charges are emitted during the subsequent light emission period Th. A voltage necessary for electron emission is applied to the child emitting element 12B so that electrons are emitted from the plurality of electron emitting elements 12B corresponding to the ON light emitting elements so that the ON light emitting elements emit light. Yes.
[0293] 通常、電子放出素子 12Bで発光素子を構成した場合、発光素子を発光させるには 、電子放出素子 12Bに高電圧を印加する必要がある。そのことから、発光素子への 走査時に電荷を蓄積してさらに発光を行わせる場合、 1つの発光素子を発光させる 期間（例えば 1フレーム）にわたつて高電圧を印加する必要があり、消費電力が大きく なるという問題がある。また、各電子放出素子 12Bを選択し、データ信号 Sdを供給す る回路も高電圧に対応した回路にする必要がある。  [0293] Normally, when a light-emitting element is constituted by the electron-emitting device 12B, it is necessary to apply a high voltage to the electron-emitting device 12B in order to cause the light-emitting device to emit light. For this reason, when accumulating charges during scanning of the light emitting element to cause further light emission, it is necessary to apply a high voltage over a period of light emission of one light emitting element (for example, one frame), and power consumption is reduced. There is a problem of growing. In addition, the circuit that selects each electron-emitting device 12B and supplies the data signal Sd needs to be a circuit that supports high voltage.
[0294] しかし、この例では、全ての電子放出素子 12Bに電荷を蓄積した後に、全ての電子 放出素子 12Bに電圧を印加して、 ON対象の電子放出素子 12Bに対応する発光素 子を発光させると 、うものである。  [0294] However, in this example, after charges are accumulated in all the electron-emitting devices 12B, a voltage is applied to all the electron-emitting devices 12B, and light-emitting elements corresponding to the electron-emitting devices 12B to be turned on emit light. Let it be.
[0295] 従って、全ての電子放出素子 12Bに電子放出のための電圧 (放出電圧）を印加す る期間 Thは、当然に、 1フレームよりも短くなり、しかも、図 65A及び図 65Bに示す第 1の実験例力ももわ力るように、放出電圧の印加期間を短くすることができることから、 発光素子への走査時に電荷の蓄積と発光とを行わせる場合と比して消費電力を大 幅〖こ低減させることができる。  [0295] Accordingly, the period Th during which the voltage for electron emission (emission voltage) is applied to all the electron-emitting devices 12B is naturally shorter than one frame, and the first period shown in FIGS. 65A and 65B. The power consumption can be greatly increased compared to the case where charge accumulation and light emission are performed during scanning to the light emitting element because the application period of the emission voltage can be shortened so that the power of the experimental example 1 can also be understood. It can be reduced.
[0296] また、電子放出素子 12Bに電荷を蓄積する期間 Tdと、 ON対象の発光素子に対応 する電子放出素子 12Bから電子放出させる期間 Thとを分離したため、各電子放出 素子 12Bにそれぞれ輝度レベルに応じた電圧を印加するための回路の低電圧駆動 を図ることができる。 [0296] In addition, since the period Td for accumulating charges in the electron-emitting device 12B and the period Th for emitting electrons from the electron-emitting device 12B corresponding to the light-emitting device to be turned on are separated, the luminance level is set in each electron-emitting device 12B. Low voltage drive of the circuit to apply a voltage according to Can be achieved.
[0297] また、データ信号 Sd及び電荷蓄積期間 Tdの選択信号 SsZ非選択信号 Snは、行 又は列毎に駆動する必要がある力 上述した実施の形態にみられるように、駆動電 圧は数 10ボルトでよいため、蛍光表示管等で使用される安価な多出力ドライバを使 用することができる。一方、発光期間 Thにおいては、電子を十分に放出させる電圧 は、前記駆動電圧よりも大きくなる可能性があるが、全て ON対象の発光素子を一括 して駆動すればよいため、多出力の回路部品を必要としない。例えば高耐圧のディ スクリート部品で構成した 1出力だけの駆動回路があればよいため、コスト的に安価 で済む上に、回路規模も小さく済むという利点がある。上記の駆動電圧及び放電電 圧は、ェミッタ部 22の膜厚を薄くすることで、低電圧化を図ることが可能である。従つ て、膜厚の設定により、例えば駆動電圧を数ボルトにすることも可能となる。  [0297] In addition, the selection signal SsZ non-selection signal Sn for the data signal Sd and the charge accumulation period Td needs to be driven for each row or column. As shown in the above-described embodiment, the drive voltage is several Since 10 volts is sufficient, an inexpensive multi-output driver used in a fluorescent display tube or the like can be used. On the other hand, in the light emission period Th, the voltage that sufficiently discharges electrons may be higher than the drive voltage. However, since all the light emitting elements to be turned on need to be driven together, a multi-output circuit is required. No parts are required. For example, a drive circuit with only one output composed of high-voltage discrete components is sufficient, so there is an advantage that the cost is low and the circuit scale is small. The drive voltage and discharge voltage can be lowered by reducing the thickness of the emitter section 22. Therefore, for example, the drive voltage can be set to several volts by setting the film thickness.
[0298] さらに、本駆動方法によれば、行走査による第 1段階と分離して、行走査によらない 第 2段階の電子放出が全発光素子一斉に行われることから、解像度、画面サイズに よらず発光時間を確保し易ぐ輝度を大きくすることができる。  [0298] Furthermore, according to the present driving method, since the second stage of electron emission that does not depend on row scanning is performed at the same time, separately from the first stage based on row scanning, the resolution and screen size are reduced. Regardless of this, it is possible to increase the luminance that facilitates securing the light emission time.
[0299] 次に、第 2の実施の形態に係る光源 10Bに使用される電子放出素子 12Bの各種変 形例について図 72—図 77を参照しながら説明する。  Next, various modifications of the electron-emitting device 12B used in the light source 10B according to the second embodiment will be described with reference to FIGS. 72 to 77. FIG.
[0300] 先ず、第 1の変形例に係る電子放出素子 12Baは、図 72に示すように、上述した電 子放出素子 12Bとほぼ同様の構成を有する力 上部電極 18の構成材料が下部電極 20と同じである点と、上部電極 18の厚み tが 10 mよりも厚い点と、貫通部 102をェ ツチング (ウエットエッチング、ドライエッチング)やリフトオフ、レーザ等を使用して人為 的に形成している点で特徴を有する。貫通部 102の形状は、上述した電子放出素子 12Bと同様に、孔 114の形状、切欠き 128の形状、スリット 132の形状を採用すること ができる。  [0300] First, as shown in FIG. 72, the electron-emitting device 12Ba according to the first modified example has the same configuration as that of the above-described electron-emitting device 12B. In addition, the thickness t of the upper electrode 18 is thicker than 10 m, and the penetrating part 102 is artificially formed using etching (wet etching, dry etching), lift-off, laser, etc. It has characteristics in that it is. As the shape of the penetrating portion 102, the shape of the hole 114, the shape of the notch 128, and the shape of the slit 132 can be adopted as in the electron emitting device 12 </ b> B described above.
[0301] さら〖こ、上部電極 18における貫通部 102の周部 108の下面 108aは、貫通部 102 の中心に向力うに従って徐々に上方に傾斜している。この形状は、例えばリフトオフ を使用することで簡単に形成することができる。  [0301] Further, the lower surface 108a of the peripheral portion 108 of the penetrating portion 102 in the upper electrode 18 is gradually inclined upward toward the center of the penetrating portion 102. This shape can be easily formed by using, for example, lift-off.
[0302] この第 1の変形例に係る電子放出素子 12Baを使用した光源 10Bにおいても、上述 した電子放出素子 12Bを用いた場合と同様に、高い電界集中を容易に発生させるこ とができ、しかも、電子放出箇所を多くすることができ、電子放出について高出力、高 効率を図ることができ、低電圧駆動 (低消費電力)も可能となる。 [0302] In the light source 10B using the electron-emitting device 12Ba according to the first modification, as in the case of using the electron-emitting device 12B described above, high electric field concentration can be easily generated. In addition, the number of electron emission locations can be increased, high output and high efficiency can be achieved for electron emission, and low voltage driving (low power consumption) is also possible.
[0303] また、図 73に示す第 2の変形例に係る電子放出素子 12Bbのように、ェミッタ部 22 の上面のうち、貫通部 102と対応する部分にフローティング電極 174を存在させても よい。  Further, like the electron-emitting device 12Bb according to the second modified example shown in FIG. 73, the floating electrode 174 may be present in a portion corresponding to the penetrating portion 102 in the upper surface of the emitter portion 22.
[0304] また、図 74に示す第 3の変形例に係る電子放出素子 12Bcのように、上部電極 18と して、断面形状がほぼ T字状とされた電極を形成するようにしてもょ ヽ。  [0304] Further, like the electron-emitting device 12Bc according to the third modification shown in FIG. 74, an electrode having a substantially T-shaped cross section may be formed as the upper electrode 18.ヽ.
[0305] また、図 75に示す第 4の変形例に係る電子放出素子 12Bdのように、上部電極 18 の形状、特に、上部電極 18の貫通部 102の周部 108が浮き上がった形状としてもよ い。これは、上部電極 18となる膜材料の中に、焼成工程中においてガス化する材料 を含ませておけばよい。これにより、焼成工程において、前記材料がガス化し、その 跡として、上部電極 18に多数の貫通部 102が形成されると共に、貫通部 102の周部 108が浮き上がった形状になる。  Further, like the electron-emitting device 12Bd according to the fourth modification shown in FIG. 75, the shape of the upper electrode 18, particularly, the shape in which the peripheral portion 108 of the through-hole 102 of the upper electrode 18 is raised may be used. Yes. In this case, the film material to be the upper electrode 18 may include a material that is gasified during the firing process. Thereby, in the firing step, the material is gasified, and as a result, a large number of through portions 102 are formed in the upper electrode 18 and the peripheral portion 108 of the through portion 102 is lifted.
[0306] 次に、第 5の変形例に係る電子放出素子 12Beについて図 76を参照しながら説明 する。  [0306] Next, an electron-emitting device 12Be according to a fifth modification will be described with reference to FIG.
[0307] この第 5の変形例に係る電子放出素子 12Beは、図 76に示すように、上述した電子 放出素子 12Bとほぼ同様の構成を有する力 例えばセラミックスで構成された 1つの 基板 176を有する点と、下部電極 20が基板 176上に形成され、ェミッタ部 22が基板 176上であって、かつ、下部電極 20を覆うように形成され、さらに上部電極 18がエミ ッタ部 22上に形成されて 、る点で異なる。  [0307] As shown in Fig. 76, the electron-emitting device 12Be according to the fifth modified example includes a single substrate 176 made of a force having substantially the same configuration as the electron-emitting device 12B described above, for example, ceramics. The lower electrode 20 is formed on the substrate 176, the emitter 22 is formed on the substrate 176 so as to cover the lower electrode 20, and the upper electrode 18 is formed on the emitter 22. There are different points.
[0308] 基板 176の内部には、各ェミッタ部 22が形成される部分に対応した位置に、後述 する薄肉部を形成するための空所 178が設けられている。空所 178は、基板 176の 他端面に設けられた径の小さい貫通孔 180を通じて外部と連通されている。  [0308] Inside the substrate 176, a space 178 for forming a thin portion described later is provided at a position corresponding to a portion where each of the emitter portions 22 is formed. The void 178 communicates with the outside through a small-diameter through hole 180 provided on the other end surface of the substrate 176.
[0309] 前記基板 176のうち、空所 178の形成されている部分が薄肉とされ (以下、薄肉部 182と記す）、それ以外の部分が厚肉とされて前記薄肉部 182を支持する固定部 18 4として機能するようになって 、る。  [0309] Of the substrate 176, the portion where the void 178 is formed is thin (hereinafter referred to as the thin portion 182), and the other portions are thick and are fixed to support the thin portion 182. Part 18 4 is now functioning.
[0310] つまり、基板 176は、最下層である基板層 176Aと中間層であるスぺーサ層 176Bと 最上層である薄板層 176Cの積層体であって、スぺーサ層 176Bのうち、ェミッタ部 2 2に対応する箇所に空所 178が形成された一体構造体として把握することができる。 基板層 176Aは、補強用基板として機能するほか、配線用の基板としても機能するよ うになつている。なお、前記基板 176は、基板層 176A、スぺーサ層 176B及び薄板 層 176Cの一体焼成で形成してもよ 、し、これら層 176A— 176Cを接着して形成す るようにしてちょい。 [0310] That is, the substrate 176 is a laminate of the substrate layer 176A as the lowermost layer, the spacer layer 176B as the intermediate layer, and the thin plate layer 176C as the uppermost layer. Part 2 It can be grasped as an integral structure in which a void 178 is formed at a location corresponding to 2. The substrate layer 176A functions not only as a reinforcing substrate but also as a wiring substrate. The substrate 176 may be formed by integrally firing the substrate layer 176A, the spacer layer 176B, and the thin plate layer 176C, or may be formed by adhering these layers 176A-176C.
[0311] 薄肉部 182は、高耐熱性材料であることが好ましい。その理由は、ェミッタ部 22を 有機接着剤等の耐熱性に劣る材料を用いずに、固定部 184によって直接薄肉部 18 2を支持させる構造とする場合、少なくともェミッタ部 22の形成時に、薄肉部 182が変 質しないようにするため、薄肉部 182は、高耐熱性材料であることが好ましい。  [0311] The thin portion 182 is preferably a high heat resistant material. The reason is that when the emitter 22 is structured to directly support the thin portion 18 2 by the fixing portion 184 without using a material having poor heat resistance such as an organic adhesive, at least when the emitter 22 is formed, the thin portion In order to prevent 182 from being altered, the thin-walled portion 182 is preferably a high heat resistant material.
[0312] また、薄肉部 182は、基板 176上に形成される上部電極 18に通じる配線と下部電 極 20に通じる配線との電気的な分離を行うために、電気絶縁材料であることが好まし い。  [0312] In addition, the thin-walled portion 182 is preferably an electrically insulating material in order to electrically separate the wiring leading to the upper electrode 18 and the wiring leading to the lower electrode 20 formed on the substrate 176. Good.
[0313] 従って、薄肉部 182の材料としては、高耐熱性の金属あるいはその金属表面をガラ ス等のセラミック材料で被覆したホーロウ等の材料であってもよ 、が、セラミックスが最 適である。  [0313] Therefore, the material of the thin portion 182 may be a highly heat-resistant metal or a material such as a hollow whose surface is covered with a ceramic material such as glass, but ceramics is most suitable. .
[0314] 薄肉部 182を構成するセラミックスとしては、例えば、安定ィ匕された酸ィ匕ジルコユウ ム、酸ィ匕アルミニウム、酸化マグネシウム、酸化チタン、スピネル、ムライト、窒化アルミ ユウム、窒化珪素、ガラス、これらの混合物等を使用することができる。その中でも、 酸ィ匕アルミニウム及び安定ィ匕された酸ィ匕ジルコニウム力 強度及び剛性の観点から 好ましい。安定化された酸ィ匕ジルコニウムは、機械的強度が比較的高いこと、靭性が 比較的高 、こと、上部電極 18及び下部電極 20との化学反応が比較的小さ 、こと等 の観点力も特に好適である。なお、安定ィ匕された酸ィ匕ジルコニウムとは、安定化酸化 ジルコニウム及び部分安定化酸化ジルコニウムを包含する。安定化された酸化ジル コ -ゥムでは、立方晶等の結晶構造をとるため、相転移が生じない。  [0314] Ceramics constituting the thin portion 182 include, for example, stabilized acid-zirconium, acid-aluminum, magnesium oxide, titanium oxide, spinel, mullite, aluminum nitride, silicon nitride, glass, Mixtures of these can be used. Among them, acid aluminum and stable acid zirconium power are preferable from the viewpoint of strength and rigidity. Stabilized zirconium oxide is particularly suitable for viewpoints such as relatively high mechanical strength, relatively high toughness, and relatively small chemical reaction with upper electrode 18 and lower electrode 20. It is. The stabilized acid zirconium oxide includes stabilized zirconium oxide and partially stabilized zirconium oxide. Stabilized zirconium oxide has a crystal structure such as a cubic crystal, so no phase transition occurs.
[0315] 一方、酸ィ匕ジルコニウムは、 1000°C前後で単斜晶と正方晶との間を相転移し、こ のような相転移の際にクラックが発生するおそれがある。安定化された酸化ジルコ二 ゥムは、酸化カルシウム、酸化マグネシウム、酸化イットリウム、酸化スカンジウム、酸 ィ匕イッテルビウム、酸化セリウム、希土類金属の酸ィ匕物等の安定剤を、 1一 30モル0 /0 含有する。なお、基板 176の機械的強度を向上させるために、安定化剤が酸化イット リウムを含有すると好適である。この場合、酸化イットリウムを、好適には 1. 5— 6モル %、さらに好適には 2— 4モル0 /0含有し、さらに 0. 1— 5モル0 /0の酸化アルミニウムを 含有することが好ましい。 [0315] On the other hand, zirconium oxide has a phase transition between a monoclinic crystal and a tetragonal crystal at around 1000 ° C, and cracks may occur during such a phase transition. Oxide stabilized zirconium two © beam is calcium oxide, magnesium oxide, yttrium oxide, scandium oxide, acid I spoon ytterbium, cerium oxide, a stabilizer such as rare earth metal Sani匕物, 1 one 30 mole 0 / 0 contains. In order to improve the mechanical strength of the substrate 176, it is preferable that the stabilizer contains yttrium oxide. In this case, yttrium oxide, preferably 1. 5-6 mol%, further preferably 2-4 mole 0/0 contains additionally contains aluminum oxide 0.5 1 5 mole 0/0 preferable.
[0316] また、結晶相を、立方晶 +単斜晶の混合相、正方晶 +単斜晶の混合相、立方晶 + 正方晶 +単斜晶の混合相等とすることができる力 その中でも、主たる結晶相を、正 方晶又は正方晶 +立方晶の混合相としたものが、強度、靭性及び耐久性の観点から 最適である。 [0316] Further, the force that can make the crystal phase a cubic + monoclinic mixed phase, a tetragonal + monoclinic mixed phase, a cubic + tetragonal + monoclinic mixed phase, etc. From the viewpoints of strength, toughness, and durability, the main crystal phase is a tetragonal or tetragonal + cubic mixed phase.
[0317] 基板 176をセラミックスカゝら構成した場合、比較的多数の結晶粒が基板 176を構成 するが、基板 176の機械的強度を向上させるためには、結晶粒の平均粒径を、好適 には 0. 05— とし、さらに好適には 0. 1— とするとよい。  [0317] In the case where the substrate 176 is formed of ceramics, a relatively large number of crystal grains constitute the substrate 176. In order to improve the mechanical strength of the substrate 176, the average grain size of the crystal grains is preferably It is better to set the value to 0.05-, more preferably 0.1-.
[0318] 一方、固定部 184は、セラミックス力もなることが好ましいが、薄肉部 182の材料と同 一のセラミックスでもよいし、異なっていてもよい。固定部 184を構成するセラミックスと しては、薄肉部 182の材料と同様に、例えば、安定ィ匕された酸ィ匕ジルコニウム、酸ィ匕 アルミニウム、酸化マグネシウム、酸化チタン、スピネル、ムライト、窒化アルミニウム、 窒化珪素、ガラス、これらの混合物等を用いることができる。  [0318] On the other hand, the fixing portion 184 preferably has a ceramic force, but may be the same ceramic as the material of the thin portion 182 or may be different. Examples of the ceramic constituting the fixing portion 184 include the stabilized acid zirconium oxide, oxide aluminum, magnesium oxide, titanium oxide, spinel, mullite, and aluminum nitride, similar to the material of the thin portion 182. Silicon nitride, glass, a mixture thereof, or the like can be used.
[0319] 特に、この電子放出素子 12Beで用いられる基板 176は、酸ィ匕ジルコニウムを主成 分とする材料、酸ィ匕アルミニウムを主成分とする材料、又はこれらの混合物を主成分 とする材料等が好適に採用される。その中でも、酸ィ匕ジルコニウムを主成分としたも のがさらに好ましい。  [0319] In particular, the substrate 176 used in the electron-emitting device 12Be is made of a material mainly composed of acid zirconium, a material mainly composed of acid aluminum, or a material mainly composed of a mixture thereof. Etc. are preferably employed. Of these, those containing zirconium oxide as a main component are more preferable.
[0320] なお、焼結助剤として粘土等を加えることもあるが、酸化珪素、酸化ホウ素等のガラ ス化し易いものが過剰に含まれないように、助剤成分を調節する必要がある。なぜな ら、これらのガラス化し易い材料は、基板 176とェミッタ部 22とを接合させる上で有利 ではあるものの、基板 176とェミッタ部 22との反応を促進し、所定のェミッタ部 22の組 成を維持することが困難となり、その結果、素子特性を低下させる原因となるからであ る。  [0320] Although a clay or the like may be added as a sintering aid, it is necessary to adjust the auxiliary component so as not to include excessively glassy substances such as silicon oxide and boron oxide. This is because these materials that are easily vitrified are advantageous in bonding the substrate 176 and the emitter 22, but promote the reaction between the substrate 176 and the emitter 22, thereby forming a predetermined emitter 22. This is because it is difficult to maintain the characteristics, and as a result, the device characteristics are deteriorated.
[0321] すなわち、基板 176中の酸ィ匕珪素等は重量比で 3%以下、さらに好ましくは 1%以 下となるように制限することが好ましい。ここで、主成分とは、重量比で 50%以上の割 合で存在する成分をいう。 [0321] That is, it is preferable to limit the silicon oxide or the like in the substrate 176 to 3% or less, more preferably 1% or less by weight. Here, the main component is 50% or more by weight. A component present in combination.
[0322] また、前記薄肉部 182の厚みとェミッタ部 22の厚みは、同次元の厚みであることが 好ましい。なぜなら、薄肉部 182の厚みが極端にェミッタ部 22の厚みより厚くなると（ 1桁以上異なると）、ェミッタ部 22の焼成収縮に対して、薄肉部 182がその収縮を妨 げるように働くため、ェミッタ部 22と基板 176との界面での応力が大きくなり、はがれ 易くなる。反対に、厚みの次元が同程度であれば、ェミッタ部 22の焼成収縮に基板 1 76 (薄肉部 182)が追従し易くなるため、一体ィ匕には好適である。具体的には、薄肉 部 182の厚みは、 1一 100 /z mであることが好ましぐ 3— 50 mがさらに好ましぐ 5 一 20 mがより一層好ましい。一方、ェミッタ部 22は、その厚みとして 5— 100 mが 好ましぐ 5— 50 mがさらに好ましぐ 5— 30 mがより一層好ましい。  [0322] Further, the thickness of the thin portion 182 and the thickness of the emitter portion 22 are preferably the same dimension. This is because if the thickness of the thin portion 182 is extremely thicker than the thickness of the emitter portion 22 (by one digit or more), the thin portion 182 works to prevent the shrinkage of the emitter portion 22 from firing shrinkage. As a result, the stress at the interface between the emitter portion 22 and the substrate 176 increases, and it becomes easy to peel off. On the other hand, if the dimension of the thickness is approximately the same, the substrate 176 (thin wall portion 182) can easily follow the firing shrinkage of the emitter portion 22, which is preferable for an integrated substrate. Specifically, the thickness of the thin portion 182 is preferably 3 to 100 m, more preferably 3 to 50 m, and even more preferably 5 to 20 m. On the other hand, the thickness of the emitter 22 is preferably 5 to 100 m, more preferably 5 to 50 m, and even more preferably 5 to 30 m.
[0323] そして、基板 176上にェミッタ部 22を形成する方法としては、スクリーン印刷法、デ イツビング法、塗布法、電気泳動法、エアロゾルデポジション法等の各種厚膜形成法 や、イオンビーム法、スパッタリング法、真空蒸着法、イオンプレーティング法、化学気 相成長法 (CVD)、めっき等の各種薄膜形成法を用いることができる。特に、圧電 Z 電歪材料の粉末ィ匕したものを、ェミッタ部 22として形成し、これに低融点のガラスや ゾル粒子を含浸する方法をとることが好ましい。この手法により、 700°Cあるいは 600 °C以下といった低温での膜形成が可能となる。  [0323] And, as a method of forming the emitter portion 22 on the substrate 176, various thick film forming methods such as a screen printing method, a destaining method, a coating method, an electrophoresis method, an aerosol deposition method, and an ion beam method are used. Various thin film forming methods such as sputtering, vacuum deposition, ion plating, chemical vapor deposition (CVD), and plating can be used. In particular, it is preferable to use a method in which a powdered piezoelectric Z electrostrictive material is formed as the emitter portion 22 and impregnated with glass or sol particles having a low melting point. This method makes it possible to form a film at a low temperature of 700 ° C or 600 ° C or lower.
[0324] また、電子放出素子 12Beの焼成処理としては、基板 176上に下部電極 20となる 材料、ェミッタ部 22となる材料及び上部電極 18となる材料を順次積層してから一体 構造として焼成するようにしてもよいし、下部電極 20、ェミッタ部 22、上部電極 18を それぞれ形成するたびに熱処理 (焼成処理)して基板 176と一体構造にするようにし てもよい。なお、上部電極 18及び下部電極 20の形成方法によっては、一体化のた めの熱処理 (焼成処理)を必要としな!、場合もある。  [0324] In addition, as a firing process for the electron-emitting device 12Be, a material to be the lower electrode 20, a material to be the emitter 22 and a material to be the upper electrode 18 are sequentially stacked on the substrate 176, and then fired as an integrated structure. Alternatively, each time the lower electrode 20, the emitter part 22, and the upper electrode 18 are formed, a heat treatment (firing process) may be performed to form an integrated structure with the substrate 176. Depending on the method of forming the upper electrode 18 and the lower electrode 20, a heat treatment (firing treatment) for integration may be required!
[0325] 基板 176と、ェミッタ部 22、上部電極 18及び下部電極 20とを一体ィ匕させるための 焼成処理に係る温度としては、 500— 1400°Cの範囲、好適には、 1000— 1400°C の範囲とするとよい。さらに、膜状のェミッタ部 22を熱処理する場合、高温時にエミッ タ部 22の糸且成が不安定にならないように、ェミッタ部 22の蒸発源と共に雰囲気制御 を行 、ながら焼成処理を行うことが好ま 、。 [0326] また、ェミッタ部 22を適切な部材によって被覆し、ェミッタ部 22の表面が焼成雰囲 気に直接露出しないようにして焼成する方法を採用してもよい。この場合、被覆部材 としては、基板 176と同様の材料を用いることが好ましい。 [0325] The temperature related to the baking treatment for integrating the substrate 176 with the emitter section 22, the upper electrode 18 and the lower electrode 20 is in the range of 500-1400 ° C, preferably 1000-1400 °. C range is recommended. Furthermore, when the film-like emitter 22 is heat-treated, the firing process may be performed while controlling the atmosphere together with the evaporation source of the emitter 22 so that the yarn formation of the emitter 22 is not unstable at high temperatures. Favored ,. [0326] Alternatively, a method may be employed in which the emitter portion 22 is covered with an appropriate member, and firing is performed such that the surface of the emitter portion 22 is not directly exposed to the firing atmosphere. In this case, it is preferable to use the same material as the substrate 176 as the covering member.
[0327] この第 5の変形例に係る電子放出素子 12Beにおいては、焼成時においてェミッタ 部 22が収縮することになるが、この収縮時に発生する応力が空所 178の変形等を通 じて開放されることから、ェミッタ部 22を十分に緻密化させることができる。ェミッタ部 22の緻密化が向上することにより、耐電圧が向上すると共に、ェミッタ部 22での分極 反転並びに分極変化が効率よく行われることになり、電子放出素子 12Beとしての特 性が向上することになる。  [0327] In the electron-emitting device 12Be according to the fifth modified example, the emitter portion 22 contracts during firing, but the stress generated during the contraction is released through deformation of the void 178 or the like. Therefore, the emitter 22 can be sufficiently densified. By improving the densification of the emitter 22, the withstand voltage is improved, and the polarization inversion and polarization change in the emitter 22 are efficiently performed, thereby improving the characteristics as the electron-emitting device 12 Be. become.
[0328] 上述した第 5の変形例では、基板 176として 3層構造の基板を用いたが、その他、 図 77の第 6の変形例に係る電子放出素子 12Bfに示すように、最下層の基板層 176 Aを省略した 2層構造の基板 176aを用いてもょ 、。  [0328] In the fifth modification described above, a three-layer structure substrate was used as the substrate 176. In addition, as shown in the electron-emitting device 12Bf according to the sixth modification example in FIG. Use a two-layer substrate 176a without layer 176A.
[0329] この第 2の実施の形態に係る光源 10Bは、図 16に示す第 3の変形例に係る光源 10 Acと同様に、発光部 14Bを 2つのグループ（第 1及び第 2のグループ G1及び G2)に 分け、第 1のグループ G1に含まれる電子放出素子 12Bの発光時に、第 2のグループ G2に含まれる電子放出素子 12Bにおいて第 1のグループ G 1に含まれる電子放出 素子 12Bの電力を回収し、第 2のグループ G2に含まれる電子放出素子 12Bの発光 時に、第 1のグループ G 1に含まれる電子放出素子 12Bにお 、て第 2のグループ G2 に含まれる電子放出素子 12Bの電力を回収するようにしてもょ 、。  [0329] In the light source 10B according to the second embodiment, the light emitting unit 14B is divided into two groups (first and second groups G1), similarly to the light source 10Ac according to the third modification shown in FIG. And G2), when the electron-emitting device 12B included in the first group G1 emits light, the power of the electron-emitting device 12B included in the first group G1 in the electron-emitting device 12B included in the second group G2 When the electron-emitting devices 12B included in the second group G2 emit light, the electron-emitting devices 12B included in the second group G2 Even if you collect power.
[0330] また、第 2の実施の形態に係る光源 10Bにおいては、図 29の第 5の変形例に係る 光源 lOAeのように、 2以上の面光源部 Z1— Z6を有するようにしてもよい。図 29の例 では、 6つの面光源部 Z1— Z6を具備させた場合を示す。各面光源部 Z1— Z6は、複 数の電子放出素子 12Bが二次元的に配列されて構成され、それぞれ独立に駆動回 路 16Bが接続されている。  [0330] In addition, the light source 10B according to the second embodiment may have two or more surface light source units Z1-Z6, as in the light source lOAe according to the fifth modification example of FIG. . The example of FIG. 29 shows a case where six surface light source units Z1 to Z6 are provided. Each surface light source unit Z1-Z6 is configured by two-dimensionally arranging a plurality of electron-emitting devices 12B, and a drive circuit 16B is independently connected thereto.
[0331] これによつて、面光源部 Z1— Z6単位に発光 Z消光を制御することができ、段階的 な調光 (デジタル的な調光)を行うことができる。特に、各面光源部 Z1— Z6にそれぞ れ独立に接続される駆動回路 16Bに変調回路 60 (図 18参照）を設けることによって 、各面光源部 Z1— Z6の発光分布をそれぞれ独立に制御することができる。つまり、 デジタル的な調光にカ卩えて、アナログ的な調光を実現でき、きめ細かな調光を行うこ とがでさる。 [0331] This makes it possible to control light emission Z quenching in units of the surface light source units Z1 to Z6, and to perform stepwise light control (digital light control). In particular, by providing a modulation circuit 60 (see Fig. 18) in the drive circuit 16B that is independently connected to each surface light source unit Z1-Z6, the emission distribution of each surface light source unit Z1-Z6 can be controlled independently. can do. That means In addition to digital dimming, analog dimming can be realized and fine dimming can be performed.
[0332] また、第 2の実施の形態に係る光源 10Bにおいては、図 30に示す第 6の変形例に 係る光源 lOAfのように、第 1及び第 6の面光源部 Z1及び Z6をそれぞれ横長で、力 つ、長辺の長い長方形状とし、第 2及び第 5の面光源部をそれぞれ縦長で、かつ、長 辺が第 1及び第 6の面光源部 Z1及び Z6よりも短い長方形状とし、第 3及び第 4の面 光源部 Z3及び Z4をそれぞれ横長で、かつ、長辺が第 1及び第 6の面光源部 Z1及び Z6よりも短 ヽ長方形状としてもよ!ヽ。  [0332] Also, in the light source 10B according to the second embodiment, the first and sixth surface light source units Z1 and Z6 are horizontally long like the light source lOAf according to the sixth modification shown in FIG. Therefore, it is assumed that the rectangular shape has a long long side, the second and fifth surface light source sections are vertically long, and the long side is a rectangular shape shorter than the first and sixth surface light source sections Z1 and Z6. The third and fourth surface light source units Z3 and Z4 may be horizontally long, and the long sides may be shorter than the first and sixth surface light source units Z1 and Z6.
[0333] また、第 2の実施の形態に係る光源 10Bにおいては、図 31に示す第 7の変形例に 係る光源 lOAgのように、各面光源部 Z1— Z6に含まれる複数の電子放出素子 12B をそれぞれ 2つのグループ (第 1及び第 2のグループ G1及び G2)に分け、各面光源 部 Z1— Z6において、第 1のグループに含まれる電子放出素子 12Bの発光時に、該 第 1のグループ G1に含まれる電子放出素子 12Bの電力を、第 2のグループ G2に含 まれる電子放出素子 12Bに回収し、第 2のグループ G2に含まれる電子放出素子 12 Bの発光時に、該第 2のグループ G2に含まれる電子放出素子 12Bの電力を、第 1の グループ G1に含まれる電子放出素子 12Bに回収するようにしてもょ 、。  [0333] Also, in the light source 10B according to the second embodiment, a plurality of electron-emitting devices included in each surface light source unit Z1-Z6, as in the light source lOAg according to the seventh modification shown in FIG. 12B is divided into two groups (first and second groups G1 and G2), and each surface light source unit Z1-Z6 has the first group when the electron-emitting device 12B included in the first group emits light. The power of the electron-emitting device 12B included in G1 is recovered by the electron-emitting device 12B included in the second group G2, and when the electron-emitting device 12B included in the second group G2 emits light, The power of the electron-emitting device 12B included in the group G2 may be collected by the electron-emitting device 12B included in the first group G1.
[0334] また、第 2の実施の形態に係る光源 10Bにおいては、図 32に示す第 8の変形例に 係る光源 lOAhのように、 6つの面光源部 Z1— Z6を 2つのグループ（第 1及び第 2の グループ G1及び G2)に分け、第 1のグループ G1に関する面光源部 Z1— Z3の各電 子放出素子 12Bの発光時に、これら電子放出素子 12Bの電力を、第 2のグループ G 2に関する面光源部 Z4— Z6の電子放出素子 12Bに回収し、第 2のグループ G2に関 する面光源部 Z4— Z6の各電子放出素子 12Bの発光時に、これら電子放出素子 12 Bの電力を、第 1のグループ G1に関する面光源部 Z1— Z3の電子放出素子 12Bに 回収するようにしてもよ ヽ。  [0334] In addition, in the light source 10B according to the second embodiment, as in the light source lOAh according to the eighth modification shown in FIG. And the second group G1 and G2), and when the light emitting elements 12B of the surface light source units Z1 to Z3 relating to the first group G1 emit light, the power of these electron emitting elements 12B is changed to the second group G2 Are collected in the electron emitters 12B of the surface light source parts Z4—Z6, and the power of the electron emitters 12B in the surface light source parts Z4—Z6 of the second group G2 is emitted at the time of light emission. The surface light source unit Z1-Z3 related to the first group G1 may be collected in the electron-emitting device 12B.
[0335] また、第 2の実施の形態に係る光源 10Bにおいては、図 33—図 37に示す第 9一第 13の変形例に係る光源 lOAi— lOAmに示すような構成を採用してもよい。  [0335] Also, in the light source 10B according to the second embodiment, the configuration shown in the light source lOAi- lOAm according to the ninth to the thirteenth modification examples shown in Figs. 33 to 37 may be adopted. .
[0336] 第 1の実施の形態に係る光源 10A (各種変形例を含む)及び第 2の実施の形態に 係る光源 10B (各種変形例を含む）は、以下のような効果を奏することができる。 [0337] (1)高輝度化、低消費電力化が実現できるという面から、輝度仕様として 2000ルーメ ンが必要なプロジェクタ用の光源に最適である。 The light source 10A according to the first embodiment (including various modifications) and the light source 10B according to the second embodiment (including various modifications) can have the following effects. . [0337] (1) Because it can achieve high brightness and low power consumption, it is optimal for projector light sources that require 2000 lumens as a brightness specification.
[0338] (2)高輝度二次元アレー光源を容易に実現できることと、動作温度範囲が広ぐ屋外 環境でも発光効率に変化がないことから、 LEDの代替用途として有望である。例え ば信号機等の二次元アレー LEDモジュールの代替として最適である。なお、 LEDは(2) It is promising as an alternative to LED because it can easily realize a high-brightness two-dimensional array light source and there is no change in luminous efficiency even in outdoor environments where the operating temperature range is wide. For example, it is ideal as an alternative to two-dimensional array LED modules such as traffic lights. The LED is
、 25°C以上で許容電流が低下し、低輝度となる。 At 25 ° C or higher, the allowable current decreases and the brightness decreases.
[0339] (3)電子放出素子を二次元配列して構成される面光源は、素子単位で点灯 Z消灯 が制御可能であるため、発光領域の一部分を点灯 Z消灯するような用途に好適であ る。また、瞬時点灯が可能であるため、ウォーミングアップの時間が不要である。さら に、液晶ディスプレイ用のバックライトとして適用した場合は、高速点灯による動画画 質の改善 (動画ぼやけの改善)も可能である。 [0339] (3) Since a surface light source configured by two-dimensionally arranging electron-emitting devices can be controlled to be turned on / off in units of elements, it is suitable for applications in which a part of the light emitting area is turned on / off. is there. In addition, since instant lighting is possible, no warm-up time is required. Furthermore, when applied as a backlight for liquid crystal displays, it is also possible to improve moving image quality (improving moving image blurring) by high-speed lighting.
[0340] なお、この発明に係る光源は、上述の実施の形態に限らず、この発明の要旨を逸 脱することなぐ種々の構成を採り得ることはもちろんである。  [0340] It should be noted that the light source according to the present invention is not limited to the above-described embodiment, but can of course have various configurations without departing from the gist of the present invention.

Claims

請求の範囲 The scope of the claims
[1] 電子が物質に衝突することによって光を発生する光源において、  [1] In a light source that generates light when electrons collide with matter,
前記電子の発生源は、電子放出素子（12A)であり、  The electron generation source is an electron-emitting device (12A),
前記電子放出素子（12A)は、  The electron-emitting device (12A)
誘電体にて構成されたェミッタ部（22)と、前記ェミッタ部（22)に形成された第 1の 電極及び第 2の電極とを有し、  An emitter part (22) made of a dielectric, and a first electrode and a second electrode formed on the emitter part (22);
前記第 1の電極（18)と前記第 2の電極（20)間に駆動電圧 (Va)が印加されること によって、少なくとも前記ェミッタ部（20)の一部が分極反転あるいは分極変化される ことで電子放出を行うことを特徴とする光源。  By applying a drive voltage (Va) between the first electrode (18) and the second electrode (20), at least a part of the emitter (20) is inverted or changed in polarization. A light source characterized in that it emits electrons.
[2] 請求項 1記載の光源において、 [2] The light source according to claim 1,
前記第 1の電極（18)と前記第 2の電極 (20)間に前記駆動電圧 (Va)が印加される ことによって、少なくとも前記ェミッタ部（22)の一部が分極反転され、この分極反転に よって、前記第 1の電極（18)の周辺に双極子の正極側が配されることで、前記第 1 の電極（18)力 1次電子が引き出され、  By applying the drive voltage (Va) between the first electrode (18) and the second electrode (20), at least a part of the emitter (22) is inverted, and this polarization inversion is performed. Therefore, the first electrode (18) force primary electrons are extracted by arranging the positive electrode side of the dipole around the first electrode (18),
前記第 1の電極（18)から引き出された 1次電子が前記ェミッタ部（22)に衝突して、 該ェミッタ部（22)から 2次電子が放出されることを特徴とする光源。  A light source characterized in that primary electrons extracted from the first electrode (18) collide with the emitter (22) and secondary electrons are emitted from the emitter (22).
[3] 請求項 2記載の光源において、 [3] The light source according to claim 2,
前記第 1の電極（ 18)、前記ェミッタ部（22)及び真空雰囲気の 3重点を有し、 前記第 1の電極（18)のうち、 3重点近傍の部分から 1次電子が引き出され、 前記引き出された 1次電子が前記ェミッタ部（22)に衝突して、該ェミッタ部（22)か ら 2次電子が放出されることを特徴とする光源。  The first electrode (18), the emitter portion (22), and a three-point of vacuum atmosphere, primary electrons are extracted from a portion of the first electrode (18) near the three-point, A light source, wherein the extracted primary electrons collide with the emitter (22) and secondary electrons are emitted from the emitter (22).
[4] 電子が衝突することによって光を発生する光源において、 [4] In a light source that generates light when electrons collide,
前記電子の発生源が電子放出素子（12B)であり、  The electron generation source is an electron-emitting device (12B),
前記電子放出素子（12B)は、  The electron-emitting device (12B)
誘電体で構成されたェミッタ部（22)と、電子放出のための駆動電圧 (Va)が印加さ れる第 1の電極（18)及び第 2の電極 (20)とを有し、  An emitter section (22) made of a dielectric, and a first electrode (18) and a second electrode (20) to which a drive voltage (Va) for electron emission is applied;
前記第 1の電極（18)は、前記ェミッタ部（22)の第 1の面に形成され、  The first electrode (18) is formed on the first surface of the emitter (22),
前記第 2の電極（20)は、前記ェミッタ部（22)の第 2の面に形成され、 少なくとも前記第 1の電極（18)は、前記ェミッタ部（22)が露出される複数の貫通部 (102)を有し、 The second electrode (20) is formed on the second surface of the emitter (22), At least the first electrode (18) has a plurality of through portions (102) from which the emitter (22) is exposed,
前記第 1の電極（18)のうち、前記貫通部（102)の周部（108)における前記ェミツ タ部（22)と対向する面（102a)力 前記ェミッタ部（22)力も離間して 、ることを特徴 とする光源。  Of the first electrode (18), the surface (102a) force facing the emitter portion (22) in the peripheral portion (108) of the penetrating portion (102) is also separated from the emitter portion (22) force. A light source characterized by
[5] 請求項 4記載の光源において、 [5] The light source according to claim 4,
前記電子放出素子（10B)は、  The electron-emitting device (10B)
第 1段階に、前記第 1の電極（18)力 前記ェミッタ部（22)に向けて電子放出が行 われて、前記ェミッタ部（22)が帯電され、  In the first stage, the first electrode (18) force emits electrons toward the emitter (22), and the emitter (22) is charged,
第 2段階に、前記ェミッタ部（22)力 電子放出が行われることを特徴とする光源。  In the second stage, the emitter (22) force electron emission is performed.
[6] 請求項 4又は 5記載の光源において、 [6] The light source according to claim 4 or 5,
前記第 1段階における前記ェミッタ部（22)の帯電量に応じた電子が、前記第 2段 階に前記ェミッタ部（22)力も放出されることを特徴とする光源。  The light source according to claim 1, wherein electrons corresponding to a charge amount of the emitter section (22) in the first stage are also emitted to the second stage by the emitter section (22) force.
[7] 請求項 4一 6の!、ずれ力 1項に記載の光源にぉ 、て、 [7] Claim 4-1 6 !, displacement force
前記第 1段階における前記ェミッタ部（22)の帯電量が、前記第 2段階での電子放 出が行われるまで維持されることを特徴とする光源。  The light source characterized in that the charge amount of the emitter (22) in the first stage is maintained until the electron emission in the second stage is performed.
[8] 請求項 1一 7のいずれか 1項に記載の光源において、 [8] The light source according to any one of claims 1 to 7,
前記ェミッタ部（22)は、圧電材料、反強誘電体材料又は電歪材料で構成されてい ることを特徴とする光源。  The light emitter (22) is composed of a piezoelectric material, an antiferroelectric material, or an electrostrictive material.
[9] 請求項 1一 8のいずれか 1項に記載の光源において、 [9] The light source according to any one of claims 1 to 8,
前記第 1の電極（18)と前記第 2の電極（20)間に前記ェミッタ部（22)の少なくとも 一部を分極反転あるいは分極変化させるための交流パルスを印加する手段（16A、 16B)を有し、  Means (16A, 16B) for applying an AC pulse for reversing or changing polarization of at least part of the emitter section (22) between the first electrode (18) and the second electrode (20); Have
前記ェミッタ部（22)力も電子を間欠的に放出することを特徴とする光源。  A light source characterized in that the emitter (22) force also emits electrons intermittently.
[10] 請求項 9記載の光源において、 [10] The light source according to claim 9,
1回の電子放出による発光が消光する前に次の電子放出を行うことで、連続発光す ることを特徴とする光源。  A light source that emits light continuously by emitting the next electron before quenching the light emitted by one electron emission.
[11] 請求項 1一 10のいずれ力 1項に記載の光源において、 前記電子放出素子（12A、 12B)を複数有し、該複数の電子放出素子（12A、 12B )が二次元的に配列されていることを特徴とする光源。 [11] In the light source according to any one of claims 1 to 10, A light source comprising a plurality of the electron-emitting devices (12A, 12B), wherein the plurality of electron-emitting devices (12A, 12B) are two-dimensionally arranged.
[12] 請求項 11記載の光源において、 [12] The light source according to claim 11,
前記複数の電子放出素子（12A、 12B)が 2つのグループに分けられ、 一方のグループに含まれる電子放出素子（12A、 12B)の発光時に、他方のダル ープに含まれる電子放出素子（12A、 12B)力 前記一方のグループに含まれる電 子放出素子（12A、 12B)の電力を回収し、  The plurality of electron-emitting devices (12A, 12B) are divided into two groups. When the electron-emitting devices (12A, 12B) included in one group emit light, the electron-emitting devices (12A, 12A) included in the other 12B) Force Collects the electric power of the electron-emitting devices (12A, 12B) included in the one group,
前記他方のグループに含まれる電子放出素子（12A、 12B)の発光時に、一方の グループに含まれる電子放出素子（12A、 12B)力 前記他方のグループに含まれる 電子放出素子（12A、 12B)の電力を回収する手段（50)を有することを特徴とする光 源。  When the electron-emitting devices (12A, 12B) included in the other group emit light, the force of the electron-emitting devices (12A, 12B) included in one group of the electron-emitting devices (12A, 12B) included in the other group A light source comprising means (50) for recovering electric power.
[13] 請求項 1一 12のいずれ力 1項に記載の光源において、  [13] In the light source according to any one of claims 1 to 12,
前記駆動電圧 (Va)を制御信号 (Sh)に基づいて変調して、前記電子放出素子（1 2A、 12B)の電子放出量を制御することによって調光を行う手段（60)を有することを 特徴とする光源。  Means for modulating light by modulating the drive voltage (Va) based on a control signal (Sh) and controlling the electron emission amount of the electron-emitting devices (12A, 12B); Characteristic light source.
[14] 請求項 1一 10のいずれ力 1項に記載の光源において、 [14] In the light source according to any one of claims 1 to 10,
2以上の面光源部（Z1— Z6)を有し、  It has two or more surface light source parts (Z1-Z6)
前記各面光源部 (Z1— Z6)は、前記電子放出素子（12A、 12B)を複数有し、該複 数の電子放出素子（12A、 12B)が二次元的に配列されていることを特徴とする光源  Each of the surface light source sections (Z1-Z6) has a plurality of the electron-emitting devices (12A, 12B), and the plurality of electron-emitting devices (12A, 12B) are two-dimensionally arranged. Light source
[15] 請求項 14記載の光源において、 [15] The light source according to claim 14,
前記各面光源部 (Z1— Z6)に含まれる前記複数の電子放出素子（12A、 12B)が それぞれ 2つのグループに分けられ、  The plurality of electron-emitting devices (12A, 12B) included in each surface light source unit (Z1-Z6) are each divided into two groups,
一方のグループに含まれる電子放出素子（12A、 12B)の発光時に、他方のダル ープに含まれる電子放出素子（12A、 12B)力 前記一方のグループに含まれる電 子放出素子（12A、 12B)の電力を回収し、  When the electron-emitting device (12A, 12B) included in one group emits light, the electron-emitting device (12A, 12B) force included in the other loop Electron-emitting device (12A, 12B) included in the one group )
前記他方のグループに含まれる電子放出素子（12A、 12B)の発光時に、一方の グループに含まれる電子放出素子（12A、 12B)力 前記他方のグループに含まれる 電子放出素子（12A、 12B)の電力を回収する手段を有することを特徴とする光源。 When the electron-emitting device (12A, 12B) included in the other group emits light, the electron-emitting device (12A, 12B) force included in one group is included in the other group A light source comprising means for recovering electric power of the electron-emitting devices (12A, 12B).
[16] 請求項 14記載の光源において、 [16] The light source according to claim 14,
前記 2以上の面光源部（Z1— Z6)が 2つのグループに分けられ、  The two or more surface light source parts (Z1-Z6) are divided into two groups,
一方のグループに含まれる電子放出素子（12A、 12B)の発光時に、他方のダル ープに含まれる電子放出素子（12A、 12B)力 前記一方のグループに含まれる電 子放出素子（12A、 12B)の電力を回収し、  When the electron-emitting device (12A, 12B) included in one group emits light, the electron-emitting device (12A, 12B) force included in the other loop Electron-emitting device (12A, 12B) included in the one group )
前記他方のグループに含まれる電子放出素子（12A、 12B)の発光時に、一方の グループに含まれる電子放出素子（12A、 12B)力 前記他方のグループに含まれる 電子放出素子（12A、 12B)の電力を回収する手段を有することを特徴とする光源。  When the electron-emitting devices (12A, 12B) included in the other group emit light, the force of the electron-emitting devices (12A, 12B) included in one group of the electron-emitting devices (12A, 12B) included in the other group A light source comprising means for collecting electric power.
[17] 請求項 14一 16のいずれ力 1項に記載の光源において、 [17] In the light source according to any one of claims 14 to 16,
前記各面光源部 (Z1— Z6)について、それぞれ電子放出素子（12A、 12B)に印 加される駆動電圧 (Va)を、対応する制御信号 (Sh)に基づいて変調して、前記電子 放出素子（12A、 12B)の電子放出量を制御することによって各面光源部 (Z1— Z6) の調光を行う手段を有することを特徴とする光源。  For each of the surface light source sections (Z1 to Z6), the driving voltage (Va) applied to the electron-emitting devices (12A, 12B) is modulated based on the corresponding control signal (Sh), and the electron emission is performed. A light source comprising means for dimming each surface light source section (Z1-Z6) by controlling an electron emission amount of the element (12A, 12B).
PCT/JP2004/019587 2004-12-28 2004-12-28 Light source WO2006070445A1 (en)

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Citations (4)

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JPH11338418A (en) * 1998-05-26 1999-12-10 Mitsubishi Electric Corp Driving method of plasma display panel and plasma display device
JP2001060116A (en) * 1999-08-20 2001-03-06 Ngk Insulators Ltd Driving circuit for piezoelectric/electrostriction element
JP2004228063A (en) * 2002-11-29 2004-08-12 Ngk Insulators Ltd Electron emission method of electron emission element
JP2004228064A (en) * 2002-11-29 2004-08-12 Ngk Insulators Ltd Electron emission element and light emission element

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11338418A (en) * 1998-05-26 1999-12-10 Mitsubishi Electric Corp Driving method of plasma display panel and plasma display device
JP2001060116A (en) * 1999-08-20 2001-03-06 Ngk Insulators Ltd Driving circuit for piezoelectric/electrostriction element
JP2004228063A (en) * 2002-11-29 2004-08-12 Ngk Insulators Ltd Electron emission method of electron emission element
JP2004228064A (en) * 2002-11-29 2004-08-12 Ngk Insulators Ltd Electron emission element and light emission element

Non-Patent Citations (1)

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Title
TAKEUCHI Y. ET AL: "Novel Display Panel Utilizing Field Effect-Ferroelectric Electron Emitters", PROCEEDINGS OF THE 11TH INTERNATIONAL DISPLAY WORKKSHOPS. THE INSTITUTE OF IMAGE INFORMATION AND TELEVISION ENGINEERS AND THE SOCIETY FOR INFORMATION DISPLAY, 8 December 2004 (2004-12-08), pages 1193 - 1196, XP002987716 *

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