CN1856857A

CN1856857A - Light source

Info

Publication number: CN1856857A
Application number: CNA2004800234687A
Authority: CN
Inventors: 武内幸久; 七泷努; 大和田岩; 赤尾隆嘉
Original assignee: NGK Insulators Ltd
Current assignee: NGK Insulators Ltd
Priority date: 2004-12-28
Filing date: 2004-12-28
Publication date: 2006-11-01
Also published as: WO2006070445A1

Abstract

A light resource has a light emitting unit that consists of plural electron emitting elements arranged in two dimensions. Control signals make driving circuits to supply working voltage onto the said electron emitting elements consisting of an planar emitting body, and upper electrodes on the top of the planar emitting body and lower electrodes on the back of the planar emitting body.

Description

Light source

Technical field

The present invention relates to use the light source (comprising area source) of electronic emission element with the upper electrode that is formed on the emitter and lower electrode.

Background technology

Recently, electronic emission element is being used in various application such as field-emitter display (FED) with drive electrode and public electrode or backlight.Being used under the situation of FED, a plurality of electronic emission elements are lined up two-dimensionally, the interval with regulation disposes a plurality of fluorophor facing to these electronic emission elements respectively again.

Prior art example as this electronic emission element, patent documentation 1～5 is for example arranged, but owing in emitter, all do not use dielectric, so there is following problem: between the electrode of facing mutually, must form processing or microfabrication, and for the electronics emission must apply high voltage, in addition, panel complex manufacturing technology, manufacturing cost height.

Therefore, consider to constitute emitter, and, in following

non-patent literature

1,2, recorded and narrated various sayings as from dielectric electronics emission with dielectric.

Patent documentation 1: the spy opens flat 1-311533 communique

Patent documentation 2: the spy opens flat 7-147131 communique

Patent documentation 3: the spy opens the 2000-285801 communique

Patent documentation 4: special public clear 46-20944 communique

Patent documentation 5: special public clear 44-26125 communique

Applied Physics that non-patent literature 1: An Gang, Shi Jing " have used the Pulse Electric component of strong dielectric negative electrode " the 68th volume, No. 5, p546～550 (1999)

Non-patent literature 2:V.F.Puchkarev, G.A.Mesyats, On the mechanism of emission fromthererroelectric ceramic cathode, J.Appl.Phys., vol.78, No.9,1 November, 1995, p.5633-5637

In above-mentioned original electronic emission element, the polarization of dielectric counter-rotating makes by the electronics of the defect level of the interface of dielectric surface, dielectric and upper electrode, dielectric inside constraint and emits.In a word, as long as cause that in dielectric polarization reversal, emitting electrons amount are certain substantially, do not depend on the level that applies potential pulse.

But have following problem: the electronics emission is unstable, and the electronics emitting times for example, just lacks practicality up to about about tens thousand of times during as light source.

Summary of the invention

The present invention considers that such problem forms, its purpose is to provide a kind of light source, in electronic emission element with the emitter that constitutes by dielectric, can suppress the excessive emission of electronics, and can prevent to follow the damage etc. of the electrode etc. of electronics emission, and can realize the raising of long lifetime and reliability.

In addition, other purposes of the present invention are to provide a kind of light source, and it can be easy to produce high electric field and concentrate, and can increase electronics emission place, can realize height output, the high efficiency of electronics emission, can also use low voltage drive.

The feature of the light source of first invention is, produce in the light source of light at the electronic impact material, the generation source of described electronics is an electronic emission element, described electronic emission element has the emitter that is made of dielectric, is formed on first electrode and second electrode on the described emitter, by between described first electrode and described second electrode, applying driving voltage, make at least a portion polarization reversal of described emitter or change polarization, carry out the electronics emission thus.Described emitter can be made of piezoelectric, antiferroelectric dielectric material or electrostriction material.

The effect of the electronic emission element of relevant first invention is described here.At first,, make at least a portion polarization reversal of emitter or change polarization by between first electrode and second electrode, applying driving voltage, electronics just from current potential be lower than second electrode described first electrode near emit.Promptly, according to this polarization reversal or change polarization, side of the positive electrode at first electrode and dipole nearby thereof produces local concentrated electric field, from described first electrode primary electron is attracted out thus, the primary electron that attracts out from described first electrode clashes into described emitter, launches secondary electron from this emitter.

Under the situation of three remittance nodes with described first electrode, described emitter and vacuum atmosphere, three remittance nodes part nearby from described first electrode attracts out with primary electron, the described primary electron that is attracted out clashes into described emitter, launches secondary electron from this emitter.Secondary electron described here obtains energy from the coulomb bump of primary electron, comprise outside emitter whole at the electronics (reflection electronic) of emitter near surface scattering of electronics and auger electrons in the outbound solid, primary electron.In addition, the thickness of described first electrode as thin as a wafer (under～10nm) the situation, emitting electrons from the interface of this first electrode and emitter.

Because electronics is launched out according to such principle, so light source of the present invention can stably carry out the electronics emission, the number of times of electronics emission also can reach 2,000,000,000 times or more than it, have very strong practicality as light source.And, owing to the emitting electrons amount increases with the level of the driving voltage that applies between first electrode and second electrode substantially with being directly proportional, so can control the emitting electrons amount easily.

In addition, the electronics that is attracted out by second electrode mainly be positioned at second electrode nearby gas or the atom etc. that constitutes second electrode be ionized into cation and electronics.The atom that is positioned at described second electrode described second electrode of formation nearby is that the part of this second electrode is evaporated and the atom of generation, and this atom nearby swims at described second electrode.And, because the electronics that described ionization produces further causes the ionization of gas or described atom etc.,, electronics increases so pressing exponential function form, like this,, just become local plasma in case electronics and cation are and exist neutrally.

In addition, the cation bump that produces because of described ionization for example first electrode just may damage first electrode.

Therefore, if on first of emitter, form first electrode, and on second of emitter, form second electrode, then the electronics that emits from first electrode is used as the dipole of the emitter that local anode exists+utmost point and attracts, and first of the emitter nearby of first electrode just with the electric weight of negative polarity.As a result, the accelerator (local potential is poor) of electronics is relaxed, the electromotive force that reaches secondary is not existed, make first of described emitter wear the electric weight of negative polarity.

Therefore, the positive polarity of the anode of the part in the dipole is weakened, and the electric field strength between the negative electrode of local anode and part reduces, and stops the electronics emission.

Like this, in the present invention, can suppress the excessive emission of electronics, thus can prevent to follow the electronics emission and produce to the damage of first electrode etc., and can realize using the long lifetime of light source of electronic emission element and the raising of reliability.

Then, feature about second light source of inventing is, produce in the light source of light at bump by electronics, the generation source of described electronics is an electronic emission element, described electronic emission element has the emitter that is made of dielectric, apply first electrode and second electrode of the driving voltage that is used for the electronics emission, described first electrode is formed on first of described emitter, described second electrode is formed on second of described emitter, at least described first electrode has a plurality of breakthrough parts that described emitter reveals, and the face in the face of described emitter around the described breakthrough part in described first electrode leaves described emitter (second invention).In this case, in the phase I, described electronic emission element carries out the electronics emission from described first electrode to described emitter, makes described emitter charged, can also carry out the electronics emission from described emitter in second stage.

The effect of the electronic emission element of relevant second invention is described here.At first, between first electrode and second electrode, apply driving voltage.This driving voltage is defined as pulse voltage or alternating voltage process in time and sharply is changed to the level that is below or above reference voltage from the level that is higher or lower than reference voltage (for example 0V).

In addition, be formed with triple tandem areas in the place that first of emitter, first electrode contact with medium (for example vacuum) around this electronic emission element.Here, so-called triple tandem area is defined as concentrating portion by first electrode, emitter with the electric field that contacting of vacuum forms.In addition, also comprise the three remittance nodes that first electrode, emitter and vacuum exist as a point at described triple tandem areas.Among the present invention, triple tandem areas just be formed on a plurality of breakthrough parts around or the surrounding edge portion of first electrode.Therefore, in case apply driving voltage as mentioned above between first electrode and second electrode, at above-mentioned triple tandem areas electric field just takes place and concentrate.

In addition, in the phase I, the voltage that is higher or lower than reference voltage is applied between first electrode and second electrode, concentrate at the electric field that above-mentioned triple tandem areas for example just produce facing one direction, carry out electronics emission from first electrode to emitter, for example electronics put aside in emitter corresponding near the part the surrounding edge portion of the part of the breakthrough part of first electrode or first electrode.That is, emitter is charged.At this moment, first electrode just plays the electronics supply source.

Then, in second stage, the level of driving voltage is die-offed, in case the voltage that is below or above reference voltage is applied between first electrode and second electrode, specifically, dipole (surface of emitter is negative polarity) to the emitter of reciprocal polarization reversal having taken place just driving away from emitter corresponding near the charged electronics surrounding edge portion of the part of the breakthrough part of first electrode or first electrode, and has launched electronics from the part of having put aside electronics described in the emitter by breakthrough part.Certainly, also near the periphery of first electrode, launch electronics.At this moment, corresponding with the carried charge of described emitter in described phase I electronics is launched out from described emitter in described second stage.In addition, the carried charge of the described emitter in the described phase I is maintained to till the electronics emission of carrying out described second stage.

And, in this electronic emission element, at first, by on first electrode, forming a plurality of breakthrough parts, near the periphery of each breakthrough part and first electrode, launch electronics equably, alleviated the dispersion of electronics emission overall permanence, the emission of control electronics improves electronic transmitting efficiency simultaneously easily.

In addition, this second invention since described breakthrough part perimembranous in described first electrode in the face of property between the face of emitter and the described emitter is formed with the gap, so when applying driving voltage, it is concentrated to be easy to generate electric field at this gap portion.This just can improve electronic transmitting efficiency, can realize the lower voltage (with low level electronics emission) of driving voltage simultaneously.

As mentioned above, property formation gap between the face of facing described emitter of the described breakthrough part perimembranous of second invention in described first electrode and the described emitter, breakthrough part perimembranous in first electrode just is eaves shape (flange-like), so the electric field of gap portion is concentrated just big, correspondingly, also just launch electronics from the part (breakthrough part perimembranous) of described eaves shape easily.This just can realize height output, the high efficiency of electronics emission, and the while can be realized the lower voltage of driving voltage.And, because the breakthrough part perimembranous in first electrode plays gate electrode (control electrode, focused electron lens etc.), so can improve the straightline propagation of emitting electrons.For example constitute arranging a plurality of electronic emission elements under the situation of electron source of display, this just helps reducing crosstalks.

Like this, in second invention, can easily produce high electric field and concentrate, and can increase electronics emission place, can realize height output, the high efficiency of electronics emission, can also realize low voltage drive (low consumpting power) simultaneously.

And, about also can having, the light sources of first and second inventions between described first electrode and described second electrode, apply at least a portion polarization reversal that is used for making described emitter or the unit that changes the alternating-current pulse that polarizes, from described emitter emitting electrons discontinuously.In this case, also can before the luminous delustring that the primary electron emission causes, carry out electronics emission next time, thus luminous continuously.

In addition, the light sources of relevant first and second inventions dispose third electrode in the face of on the position of described first electrode in can be above emitter, apply fluorophor on this third electrode.In this case, a part of electronics in the electronics that is emitted is introduced in third electrode, and the activating fluorescent body, externally presents light-emitting phosphor.

In addition, the light source of relevant first and second inventions can be configured in fluorophor the periphery of electronic emission element, in the atmosphere between electronic emission element and fluorophor, for example charges into mercury grain etc.In this case, a part of electronic impact mercury grain in the electronics that is emitted makes the mercury grain be in excited state, and sends ultraviolet ray.This ultraviolet ray is mapped to the fluorophor of periphery, activating fluorescent body and externally present light-emitting phosphor.

And, in aforesaid formation, also can line up a plurality of electronic emission elements two-dimensionally.So can realize using electronic emission element and can life-saving and the area source of raising reliability.

Here, use the advantage that area source is described with the difference of display, area source is different from display, because all the time can be luminous comprehensively, so just needn't carry out the driving of complexity such as for example line scanning, can carry out static drive in the lump.And, owing to need not to carry out control based on the luminous point diameter of electronics emission, so between electronic emission element and fluorophor, needn't be provided with as the control electrode of for example condenser lens etc.This just can simplify mechanical structure and circuit structure.

Display must be handled the data-signal that changes at a high speed according to picture signal.Therefore, driving voltage is the complicated wave form according to hierarchical modulation.On the other hand, because area source needn't be handled the data-signal that changes at a high speed according to picture signal, so can use simple waveform (pulse period and pulsewidth are respectively certain waveform) as driving voltage.As a result, under situation about the Power Recovery circuit being connected on the area source, not only can set circuit constant, circuit switching timing of this Power Recovery circuit etc. accurately, but also can reclaim the power of the cardinal principle 100% of driving voltage.

And, described a plurality of electronic emission elements are divided into two groups, be included in electronic emission element in first group when luminous, the electronic emission element in being included in second group reclaims the power that is included in the electronic emission element in aforementioned first group; Be included in aforementioned electronic emission element in second group when luminous, the electronic emission element in being included in first group also can reclaim the power that is included in the electronic emission element in aforementioned second group.

In a word, the electronic emission element that is included in the group group in addition of carrying out luminous action is also used as the so-called buffer condenser that Power Recovery is used, thus buffer condenser needn't be set in addition, thus can dwindle erection space, reduction consumed power effectively.

In addition, in aforesaid formation, also can modulate described driving voltage, carry out light modulation by the electron emission amount of controlling described electronic emission element based on control signal.

In addition, the light source of relevant first and second inventions also can have two or its above area source portion.At this moment, described each area source portion has a plurality of described electronic emission elements, these a plurality of electronic emission elements can be lined up two-dimensionally.

Like this, just can carry out incremental dimming (digital type light-adjusting) with the luminous/delustring of area source portion unit control.Particularly, each area source portion can control the luminescence distribution of each area source portion by the unit that the light modulation of each area source portion is carried out in setting, this unit is to being applied to the driving voltage on the electronic emission element respectively, control signal according to correspondence is modulated, control the electron emission amount of described electronic emission element, carry out the light modulation of each area source portion thus.In a word, except that digital type light-adjusting, analog light modulation can also be realized, careful light modulation can be carried out.

In addition, in aforesaid formation, also can be divided into two groups to the described a plurality of electronic emission elements that are included in described each area source portion respectively, when the electronic emission element in being included in first group is luminous, is included in second group of interior electronic emission element and reclaims the power that is included in the electronic emission element in aforementioned first group; Be included in aforementioned electronic emission element in second group when luminous, the electronic emission element in being included in first group also can reclaim the power that is included in the electronic emission element in aforementioned second group.

In addition, can partly become two groups to described 2 or area source more than it, when the electronic emission element in being included in first group was luminous, the electronic emission element in being included in second group reclaimed the power that is included in the electronic emission element in aforementioned first group; Be included in aforementioned electronic emission element in second group when luminous, the electronic emission element in being included in first group also can reclaim the power that is included in the electronic emission element in aforementioned second group.

Picture is discussed above, according to light source of the present invention, in electronic emission element, can suppress the excessive emission of electronics with the luminous element that constitutes by dielectric, thereby can prevent to follow the damage of the electrode etc. of electronics emission, can realize the raising of life-time dilatation and reliability.

In addition, can be easy to generate high electric field and concentrate, and can increase electronics emission place, can realize the height output and the high efficiency of electronics emission, can also realize low voltage drive.

Description of drawings

Fig. 1 is the structure chart of the light source of first execution mode.

Fig. 2 A is the plane graph of the electrode part of electronic emission element.

Fig. 2 B is the plane graph of the electrode part in first variation.

Fig. 3 is the plane graph of the electrode part in second variation.

Fig. 4 is the oscillogram of expression from the driving voltage of drive circuit output.

Fig. 5 is the key diagram of the effect when applying voltage Va1 in expression first execution mode between upper electrode and lower electrode.

Fig. 6 is the key diagram that is illustrated in the electronics emission effect when applying voltage Va2 between upper electrode and the lower electrode.

Fig. 7 is that the charged and key diagram of the effect that the electronics emission stops oneself of the negative polarity on surface of emitter is followed in expression.

Fig. 8 is the performance plot of relation of the emission measure of the energy of the secondary electron that emitted of expression and secondary electron.

Fig. 9 A is the oscillogram of an example of expression driving voltage.

Fig. 9 B is the lower electrode of the electronic emission element in expression first execution mode and the oscillogram of the change in voltage between the upper electrode.

Figure 10 is the structure chart of first variation of the light source of first execution mode.

Figure 11 is the structure chart of second variation of the light source of first execution mode.

Figure 12 is the circuit diagram of drive circuit.

Figure 13 A is the oscillogram of the control signal of expression bright lamp/light-off.

Figure 13 B is the oscillogram of clock.

Figure 13 C is the oscillogram of commutator pulse.

Figure 13 D is the oscillogram by the driving voltage of circuit for generating temperature compensated driving voltage generation.

Figure 14 is the circuit diagram that schematically shows the preferred implementation of drive circuit.

Figure 15 is the oscillogram of the action of expression drive circuit.

Figure 16 is the structure chart of the 3rd variation of the light source of first execution mode.

Figure 17 is the oscillogram corresponding to the action of the drive circuit of the light source of the 3rd variation.

Figure 18 is the circuit diagram of the drive circuit of variation.

Figure 19 A is the oscillogram of dim signal.

Figure 19 B is that expression comes the key diagram of the mode of T2 between modulation period according to the level of dim signal.

Figure 19 C is the key diagram of the mode of (pulsewidth) during expression comes modulation voltage Va2 to apply according to the level of dim signal.

Figure 20 is the performance plot of the relation of the pulsewidth of voltage Va2 and brightness.

Figure 21 is the performance plot of the relation of collector voltage and brightness.

Figure 22 is the performance plot that is applied to the relation of voltage Va2 (level) and brightness between upper electrode and the lower electrode.

Figure 23 is the performance plot that is applied to the relation of voltage Va1 between upper electrode and the lower electrode and brightness.

Figure 24 is the structure chart of the 4th variation of the light source of first execution mode.

Figure 25 takes out the structure chart of expression to an electronic emission element of the light source of the 4th variation.

Figure 26 is at electronic emission element shown in Figure 25, based on the equivalent circuit diagram of the electric current between upper electrode and the collector electrode of flowing through.

Figure 27 is output characteristic (Vkc-Ikc characteristic) figure of electronic emission element shown in Figure 25.

Figure 28 is being provided with between upper electrode and the collector electrode under the situation of control electrode, based on the collector current of the collector electrode of flowing through and the equivalent circuit diagram of the Control current of the control electrode of flowing through.

Figure 29 is the structure chart of the 5th variation of the light source of first execution mode.

Figure 30 is the structure chart of the 6th variation of the light source of first execution mode.

Figure 31 is the structure chart of the 7th variation of the light source of first execution mode.

Figure 32 is the structure chart of the 8th variation of the light source of first execution mode.

Figure 33 is the structure chart of the 9th variation of the light source of first execution mode.

Figure 34 is the structure chart of the tenth variation of the light source of first execution mode.

Figure 35 is the structure chart of the 11 variation of the light source of first execution mode.

Figure 36 is the structure chart of the 12 variation of the light source of first execution mode.

Figure 37 is the structure chart of the 13 variation of the light source of first execution mode.

Figure 38 is the schematic partial sectional view of the electronic emission element that uses in the light source of second execution mode.

Figure 39 is the sectional drawing of amplification of the major part of electronic emission element.

Figure 40 is the plane graph of an example that is illustrated in the shape of the breakthrough part that forms on the upper electrode.

Figure 41 A is the sectional drawing of another example of upper electrode.

Figure 41 B is the sectional drawing of the amplification of upper electrode major part.

Figure 42 A is the sectional drawing of another example of expression upper electrode.

Figure 42 B is the sectional drawing of the amplification of expression upper electrode major part.

Figure 43 is the voltage oscillogram of the driving voltage of the first electronics radiation pattern.

Figure 44 is that electronics interior between second period of output of the first electronics radiation pattern is launched the key diagram of situation.

Figure 45 is the voltage oscillogram of the driving voltage of the second electronics radiation pattern.

Figure 46 is that electronics interior between second period of output of the second electronics radiation pattern is launched the key diagram of situation.

Figure 47 is the exemplary plot of section configuration of the eaves portion of upper electrode.

Figure 48 is another exemplary plot of section configuration of the eaves portion of upper electrode.

Figure 49 is another exemplary plot of section configuration of the eaves portion of upper electrode.

Figure 50 is the equivalent circuit diagram that is connected the connection status of the various capacitors between upper electrode and the lower electrode.

Figure 51 is connected the key diagram that the various capacitor volume between upper electrode and the lower electrode are calculated.

Figure 52 is the partial plan layout of first variation of the electronic emission element that uses in the light source of second execution mode.

Figure 53 is the partial plan layout of second variation of the electronic emission element that uses in the light source of second execution mode.

Figure 54 is the partial plan layout of the 3rd variation of the electronic emission element that uses in the light source of second execution mode.

Figure 55 is voltage-quantity of electric charge characteristic (voltage-amount of polarization characteristic) figure of the electronic emission element that uses in the light source of second execution mode.

Figure 56 A is the state description figure of the some p1 of Figure 55.

Figure 56 B is the state description figure of the some p2 of Figure 55.

Figure 56 C be Figure 55 from a p2 to the state description figure that puts p3.

Figure 57 A be Figure 55 from a p3 to the state description figure that puts p4.

Figure 57 B be Figure 55 to the state description figure that puts before the p4.

Figure 57 C be Figure 55 from a p4 to the state description figure that puts p6.

Figure 58 is the illuminating part that uses in the light source of second execution mode and the block diagram of drive circuit.

Figure 59 A～Figure 59 C is the oscillogram of the amplitude modulation of the pulse signal that carries out of modulation circuit.

Figure 60 is the block diagram of the signal supply circuit of variation.

Figure 61 A～Figure 61 C is the oscillogram of the pulse-width modulation of the pulse signal that carries out of pulse-width modulation circuit.

Magnetic hysteresis loop figure when Figure 62 A is the voltage Vsl that applies among Figure 59 A or Figure 61 A.

Magnetic hysteresis loop figure when Figure 62 B is the voltage Vsm that applies among Figure 59 B or Figure 61 B.

Magnetic hysteresis loop figure when Figure 62 C is the voltage Vsh that applies among Figure 59 C or Figure 61 C.

Figure 63 is the structure chart of an example of config set electrode, fluorophor and transparent panel on upper electrode.

Figure 64 is another routine structure chart of config set electrode, fluorophor and transparent panel on upper electrode.

Figure 65 A is the oscillogram of using in first experimental example (observing the experiment of the electronics emission state of electronic emission element) that writes pulse and bright lamp pulse.

Figure 65 B represents figure from the state of the electronics of electronic emission element emission with the detection voltage waveform of light-receiving module in first experimental example.

Figure 66 is the employed oscillogram that writes pulse and bright lamp pulse of second～the 4th experimental example.

Figure 67 is the result's of expression second experimental example (the experiment how electron emission amount of observation electronic emission element changes with the amplitude that writes pulse) a performance plot.

Figure 68 is the result's of expression the 3rd experimental example (the experiment how electron emission amount of observing electronic emission element changes with the amplitude of bright lamp pulse) a performance plot.

Figure 69 is the result's of expression the 4th experimental example (the experiment how electron emission amount of observation electronic emission element changes with the collector voltage level) a performance plot.

Figure 70 is the time diagram of an example of the driving method of expression light source.

Figure 71 applies the voltage relationship table in the driving method shown in Figure 70.

Figure 72 is the schematic partial sectional view of first variation of the employed electronic emission element of light source of second execution mode.

Figure 73 is the schematic partial sectional view of second variation of the employed electronic emission element of light source of second execution mode.

Figure 74 is the schematic partial sectional view of the 3rd variation of the employed electronic emission element of light source of second execution mode.

Figure 75 is the schematic partial sectional view of the 4th variation of the employed electronic emission element of light source of second execution mode.

Figure 76 is the schematic partial sectional view of the 5th variation of the employed electronic emission element of light source of second execution mode.

Figure 77 is the schematic partial sectional view of the 6th variation of the employed electronic emission element of light source of second execution mode.

Symbol description

10A, 10Aa～10Am, 10B ... light source

12A, 12Aa, 12Ab, 12B, 12Ba～12Bf ... electronic emission element

14,14A, 14B ... illuminating part

16,16A, 16A a, 16B ... drive circuit

18 ... upper electrode 20 ... lower electrode

22 ... emitter 32 ... collector electrode

34 ... fluorophor 40 ... the mercury grain

44 ... timing generating circuit 46 ... circuit for generating temperature compensated driving voltage

50 ... Power Recovery circuit 60 ... modulation circuit

102 ... breakthrough part 104 ... concavo-convex

106 ... recess 108 ... eaves portion

110 ... gap 112 ... protuberance

114 ... hole 116 ... material with flakey shape

118,122 ... aggregate 120 ... conductive material

128 ... breach 132 ... slit

134 ... floating electrode

Embodiment

The following embodiment that light source of the present invention is described with reference to Fig. 1～Figure 77.

As shown in Figure 1, the light source 10A of first execution mode has the illuminating part 14A that arranged a plurality of electronic emission element 12A two-dimensionally, each electronic emission element 12A of this illuminating part 14A is applied the drive circuit 16A of driving voltage va.

Drive circuit 16A basis is from the control signal Sc of the bright lamp of the expression/light-off of outside (bright lamp/light-off switch etc.), driving voltage Va is applied on first electrode (for example upper electrode), 18 and second electrode (lower electrode) 20 of each electronic emission element 12A each electronic emission element 12A of drive controlling.The preference of drive circuit 16A is described in the back.

As shown in Figure 1, each electronic emission element 12A have tabular emitter 22, be formed on this emitter 22 the surface described upper electrode 18 and be formed on the described lower electrode 20 at the back side of this emitter 22.Like this, because electronic emission element 12A picks up next structure to emitter 22 by upper electrode 18 and lower electrode 20, so become capacity load.Therefore, this electronic emission element 12A can be regarded as and be a kind of capacitor C (with reference to Figure 12).

Between upper electrode 18 and lower electrode 20, apply driving voltage Va from drive circuit 16A.In the example of Fig. 1, represented through resistance R 1 lower electrode 20 connect GND () and to make the current potential of this lower electrode 20 be zero situation, certainly, also can be the current potential beyond the zero potential.In addition, shown in Fig. 2 A and Fig. 2 B, carry out the applying of driving voltage Va between upper electrode 18 and lower electrode 20 by the lead-in wire electrode 24 that extends out from upper electrode 18 with from the lead-in wire electrode 26 that lower electrode 20 extends out.

In addition, as shown in Figure 1, this electronic emission element 12A is being used as under the situation of light source, the transparent panel 30 that configuration is for example formed by glass or propylene above upper electrode 18, at the collector electrode 32 that the back side of this transparent panel 30 (in the face of the face of upper electrode 18) configuration for example is made of transparency electrode, coating fluorophor 34 on this collector electrode 32.In addition, through resistance R 2 bias supply 36 (bias voltage Vc) is connected on the collector electrode 32.

In addition, certainly, 12A is configured in the vacuum space electronic emission element.As shown in Figure 1, there is electric field centrostigma A in this electronic emission element 12A, also can be defined as and comprises upper electrode 18/ emitter 22/ vacuum and be present in three on the point and converge the point of node but put A.

In addition, the vacuum degree in the atmosphere is 10 ²～1 ^-6In the scope of handkerchief for well, preferably 10 ^-3～1 ^-5Handkerchief.

Select the reason of such scope to be, under low vacuum, (1) generates plasma easily owing to gas molecule in the space is many, if excessively produce plasma, then its cation clashes into upper electrode 18 in large quantities and may make its damage, or (2) emitting electrons meeting collision gas molecule before arriving collector electrode 32, just the exciting of fluorophor 34 that the electronics that is fully quickened by collector potential (Vc) causes may be carried out insufficiently.

The another one reason is, though under high vacuum, easily from electric field centrostigma emitting electrons, exist the support of structure and the sealing of vacuum (seal) portion to become problem big, that be unfavorable for miniaturization.

Here, emitter 22 is made of dielectric.Dielectric dielectric constant is preferably than higher, for example can adopt dielectric constant more than or equal to 1000 dielectric.As such dielectric, for example can be except that barium titanate, also contain the pottery of lead zirconates, magnesium lead niobate, nickel lead niobate, zinc niobate lead, manganese lead niobate, magnesium lead tantanate, nickel lead tantanate, antimony lead stannate, lead titanates, magnesium lead tungstate, cobalt lead niobate etc. or their combination in any; Perhaps main component contains the material of these compounds more than 50%; Perhaps aforementioned pottery is added in right amount material of oxides such as lanthanum, calcium, strontium, molybdenum, tungsten, barium, niobium, zinc, nickel, manganese or their combination in any or other compound etc.

For example, in the 2 compositions series nPMN-m PT (is mole ratio with n, m) of magnesium lead niobate (PMN) and lead titanates (PT), if increase the mole ratio of PMN, then Curie point just descends, and just can increase the dielectric constant under the room temperature.

Particularly, under the situation of n=0.85～1.0, m=1.0-n, dielectric constant more than or equal to 3000 for well.For example, under the situation of n=0.91, m=0.09, obtain the dielectric constant 15000 of room temperature, under the situation of n=0.95, m=0.05, obtain the dielectric constant 20000 of room temperature.

And, in 3 composition series of magnesium lead niobate (PMN), lead titanates (PT), lead zirconates (PZ), except the mole ratio of PMN being got greatly, preferably improve dielectric constant by near the composition the accurate homotype phase boundary (MPB:MorphotropicPhase Boundary) of making regular crystal, plan cube crystalline substance or regular crystal, rhombohedron crystalline substance.For example, at PMN: PT: PZ=0.375: under 0.375: 0.25 the composition, dielectric constant is 5500; Be more preferably at PMN: PT: PZ=0.5: under 0.375: 0.125 the composition, dielectric constant is 4500.And then, preferably in the scope that can guarantee insulating properties, in these dielectrics, sneak into the metal of platinum and so on, improve dielectric constant.In this case, in dielectric, for example can sneak into platinum with 20% weight ratio.

In addition, as mentioned above, emitter 22 can adopt piezoelectric layer or antiferroelectric dielectric layer etc., under with the situation of piezoelectric layer as emitter 22, as this piezoelectric layer, for example can be the pottery that contains lead zirconates, magnesium lead niobate, nickel lead niobate, zinc niobate lead, manganese lead niobate, magnesium lead tantanate, nickel lead tantanate, antimony lead stannate, lead titanates, barium titanate, magnesium lead tungstate, cobalt lead niobate etc. or their combination in any.

Certainly, also can be that main component contains 50% or the material of these compounds of its above weight.In addition, the pottery that contains lead zirconates in the aforementioned pottery is as the constituent material of the piezoelectric layer that constitutes emitter 22, and usage frequency is the highest.

In addition, constituting under the situation of piezoelectric layer, also can use the pottery of oxides such as in described pottery, adding lanthanum, calcium, strontium, molybdenum, tungsten, barium, niobium, zinc, nickel, manganese in right amount or their combination in any or other compound etc. with pottery.In addition, also can use in described pottery and added SiO ₂, CeO ₂, Pb ₅Ge ₃O ₁₁Or the pottery of their combination in any.Specifically, be the SiO that has added 0.2% weight in the piezoelectric preferably at PT-PZ-PMN ₂Or the CeO of 0.1% weight ₂, or the Pb of 1～2% weight ₅Ge ₃O ₁₁Material.

For example, preferably use with the composition that constitutes by magnesium lead niobate, lead zirconates and lead titanates as main component, also contain the pottery of lanthanum or strontium.

The piezoelectric layer both can be fine and close, also can be porous matter, under the situation of porous matter, and its porosity preferably 40% or below it.

Using under the situation of antiferroelectric medium as emitter 22, as this antiferroelectric dielectric layer, preferably be with the lead zirconates main component material, be the material of main component and then the material that in lead zirconates, has added lanthana, the composition that is made of lead zirconates and lead stannate added the material of lead zirconates or lead niobate with lead zirconates and lead stannate.

In addition, this antiferroelectric deielectric-coating also can be a porous matter, under the situation of porous matter, and its porosity preferably 30% or below it.

And then, in emitter 22, use tantalic acid bismuthic acid strontium (SrBi ₂Ta ₂O ₉) situation under, preferably polarization reversal fatigue is little.The tired little material of this polarization reversal is a stratiform strong dielectric compound, with general formula (BiO ₂) ²⁺(A _M-1B _mO _3m+1) ^2-Expression.Here, the ion of metal A is Ca ²⁺, Sr ²⁺, Ba ²⁺, pb ²⁺, Bi ³⁺, La ³⁺Deng, the ion of metal B is Ti ⁴⁺, Ta ⁵⁺, Nb ⁵⁺Deng.And then, also can in the piezoelectric ceramic of barium titanate series, lead zirconates system, PZT system, add additive and make its semiconductor transformation.In this case, in emitter 22, also has uneven Electric Field Distribution, in that nearby just can to carry out electric field concentrated with the interface of the upper electrode 18 that helps electronics emission.

In addition, glass ingredient or other low-melting compound (for example bismuth oxide etc.) of sneaking into lead borosilicate glass and so in piezoelectric/antiferroelectric media ceramic just can reduce sintering temperature.

In addition, under by the situation that piezoelectric/antiferroelectric media ceramic constitutes, its shape also can be the laminated body of formed body, sheet of sheet or they are laminated or be bonded in other and support with the shape on the substrate.

In addition, by non-plumbous based material is used for emitter 22 etc., emitter 22 is made fusing point or the high material of evaporating temperature, the bump to electronics or ion just is difficult to damage emitter 22 thus.

And, as the method that forms emitter 22, can use various film forming methods such as various thick film forming methods such as wire mark method, infusion process, coating process, electrophoresis, atomizing sedimentation or ion beam method, sputtering method, vacuum vapour deposition, ion plating, chemical vapor-phase growing method (CVD), plating.Good especially method is that as emitter 22, formation is flooded low-melting glass or sol particles again to the material of piezoelectric/electrostrictive material powdered.Just can carry out the film formation down of 700 ℃ or 600 ℃ or its following low temperature in this way.

Here, the size of the thickness d (with reference to Fig. 1) of the emitter 22 between upper electrode 18 and the lower electrode 20 is described, preferably described thickness d is set to such an extent that during for Vak, carry out polarization reversal or change polarizing by the electric field E that represents with E=Vak/d at the voltage between upper electrode 18 and the lower electrode 20 (adding the voltage that between this upper electrode 18 and lower electrode 20, presents from the driving voltage Va of drive circuit 16A output between upper electrode 18 and the lower electrode 20).That is, described thickness d is more little, with regard to carrying out polarization reversal more or change polarization under low-voltage, can (for example be lower than 100V) under low voltage drive and carry out the electronics emission.

Upper electrode 18 is made of material as follows.That is the little and high conductor of evaporating temperature in a vacuum of sputtering raste preferably.For example, Ar preferably ⁺The sputtering raste of interior 600V is smaller or equal to 2.0, and reaches vapour pressure 1.3 * 10 ^-3The temperature of handkerchief is more than or equal to the conductor of 1800K, and platinum, molybdenum, tungsten etc. meet this class.In addition, can by high-temperature oxydation atmosphere is had repellence conductor constitute, for example, the mixture of the mixture of metal simple-substance, alloy, insulating ceramics and metal simple-substance, insulating ceramics and alloy etc.; Comparatively suitable is by the alloy with high-melting-point noble metal such as platinum, iridium, palladium, rhodium, molybdenum or silver-palladium, silver-platinum, platinum-palladium etc. is that the material of main component or the cermet material of platinum and ceramic material constitute.More suitable is by being that the material of main component constitutes with platinum or with the alloy of platinum system only.In addition,, preferably use carbon, graphite based material, for example diamond thin, diamond-like-carbon (Diamond Like Carbon), carbon nano-tube (Carbon nanotube) as electrode.In addition, the volume ratio that adds the ceramic material in the electrode material to preferably about 5～30%.

In addition, preferably use the organic metal paste that after sintering, obtains film, for example material such as platinum resin acid paste.In addition, preferably suppress the oxide electrode of polarization reversal fatigue, for example ruthenium-oxide, yttrium oxide, ruthenic acid strontium, La _1-xSr _xCoO ₃(for example x=0.3 or 0.5), La _1-xCa _xMnO ₃, La _1-xCa _xMn _1-yCo _yO ₃(for example x=0.2 y=0.05), perhaps is blended into the material that forms in the platinum resin acid paste to them.

Upper electrode 18 can use above-mentioned material to form according to the common film formation method of various film forming methods such as various thick film forming methods such as wire mark method, gunite, coating (coating) method, infusion process, coating process, electrophoresis or sputtering method, ion beam method, vacuum vapour deposition, ion plating, chemical vapor-phase growing method (CVD), plating, and the most handy the former thick film forming method forms.

The flat shape of upper electrode 18 both can be done the ellipse shown in the image 2A, also can do the ring-type of the electronic emission element 12Aa of first variation shown in the image 2B.Perhaps also can do the broach shape of the electronic emission element 12Ab of second variation shown in the image 3.

By the flat shape of upper electrode 18 is done circlewise or the broach shape, can increase also as three of upper electrode 18/ emitter 22/ vacuum of electric field centrostigma A and converge nodes, can improve electronic transmitting efficiency.

The thickness t c of upper electrode 18 (with reference to Fig. 1) smaller or equal to 20 μ m for well, preferably smaller or equal to 5 μ m.Therefore, the thickness t c of upper electrode 18 also can make smaller or equal to 100nm.The thickness t c of upper electrode 18 is made as thin as a wafer under the situation of (10nm or its following), electronics just emits from the interface of upper electrode 18 and emitter 22, can further improve electronic transmitting efficiency.

On the other hand, lower electrode 20 adopts material and the method the same with upper electrode 18 to form, but preferably forms with above-mentioned thick film forming method.The thickness of lower electrode 20 also is that 20 μ m or its are following for well, preferably 5 μ m or below it.

Heat-treat (sintering processes) when forming emitter 22, upper electrode 18 and lower electrode 20 respectively, can be made of one structure.And the formation method of pressing upper electrode 18 and lower electrode 20 also has the situation of incorporate heat treatment (sintering processes) of needn't being used for.

Temperature as being used for emitter 22, upper electrode 18 and lower electrode 20 incorporate sintering processes can be taken as 500 ℃～1400 ℃ scope, preferably is taken as 1000 ℃～1400 ℃ scope.And then, when membranaceous emitter 22 is heat-treated, preferably when carrying out atmosphere control, the evaporation source of emitter 22 carries out sintering processes, be unlikely to make the composition instability of emitter 22 when the high temperature with history.

In addition, also can adopt emitter 22 is wrapped, make the surface of emitter 22 can directly not be exposed to sintering method in the sintering atmosphere with suitable material.

The electronics emission principle of electronic emission element 12A is described with reference to Fig. 1, Fig. 4～Fig. 9 B then.At first, as shown in Figure 4, the current potential of exporting upper electrode 18 repeatedly from the driving voltage Va of drive circuit 16A output be higher than lower electrode 20 current potential voltage Va1 during the current potential of T1 and output upper electrode 18 be lower than lower electrode 20 current potential voltage Va2 during T2.Here during the voltage Va2 of T2 output record and narrate and be driving pulse Pd.

The amplitude Vin of driving pulse Pd can with voltage Va1 subtract voltage Va2 difference (=Va1-Va2) define.

As shown in Figure 5, T1 makes applying voltage Va1 between upper electrode 18 and the lower electrode 20 during emitter 22 polarization during.As voltage Va1 can be as shown in Figure 4 direct voltage, but also can be to apply a pulse voltage or continuous several times applies pulse voltage.Here, for the processing that fully polarizes, during T1 can be compared to most during T2 long.For example this period, T2 was more preferably greater than equaling 100 μ sec.This is to set the absolute value of the voltage Va1 that polarizes less than the absolute value of voltage Va2 because of the damage of consumed power in order to prevent to apply voltage Va1 and upper electrode 18.

In addition, the level that voltage Va1 and voltage Va2 preferably can polarize reliably and handle each positive and negative electrode, for example, have under the situation of coercive voltage at the dielectric of emitter 22, the absolute value of voltage Va1 and voltage Va2 is more preferably greater than equaling coercive voltage.

In addition, as shown in Figure 6, the driving pulse Pd that applies the amplitude with specified level between upper electrode 18 and lower electrode 20 makes at least a portion generation polarization reversal of emitter 22 or changes polarization.Here, polarization reversal takes place or changes the position of polarization the positive lower part of yes upper electrode 18, even if directly over do not have upper electrode 18 and surface to expose part, nearby also carrying out polarization reversal or changing polarization at upper electrode 18 equally.In a word, because near upper electrode 18, the part that expose on the surface of emitter 22 is that the place that polarization is oozed out takes place.According to this polarization reversal or change polarization, at the side of the positive electrode of upper electrode 18 and dipole nearby thereof, internal field takes place to be concentrated, attract primary electron from upper electrode 18 thus, the primary electron that attracts to come out from upper electrode 18 clashes into emitter 22, from these emitter 22 emission secondary electrons.

As this execution mode, under the situation of three remittance node A with upper electrode 18, emitter 22 and vacuum, three remittance node A part nearby from upper electrode 18 attracts primary electron, from the primary electron bump emitter 22 that three remittance node A attract out, launch secondary electrons from this emitter 22.In addition, (under～10nm) the situation, launch electronics as thin as a wafer at the thickness of upper electrode 18 from this upper electrode 18 and the interface of emitter 22.

The effect of the driving pulse Pd that applies the amplitude with specified level is described here, in further detail.

At first, as mentioned above,, can launch secondary electron from emitter 22 by between upper electrode 18 and lower electrode 20, applying the driving pulse Pd of amplitude with specified level.That is, near the upper electrode 18 in the emitter 22 that polarization reversal takes place or taken place to change, charged dipole just attracts electronics.

In a word, in upper electrode 18, nearby form local negative electrode at interface with emitter 22, upper electrode 18 in emitter 22 is part nearby, charged dipole+utmost point becomes local anode, thus attract electronics from upper electrode 18, and the portions of electronics in these electronics that are attracted out is introduced in collector electrode 32 (with reference to Fig. 1), excited fluophor 34 externally just is rendered as light-emitting phosphor.In addition, the portions of electronics bump emitter 22 in the described electronics that is attracted is out launched secondary electron from emitter 22, and this secondary electron is introduced in collector electrode 32, excited fluophor 34.

Here, illustrate that with reference to Fig. 8 the emission of secondary electron distributes.As shown in Figure 8, the energy of most of secondary electrons almost approaches zero, from the surface emitting of emitter 22 to vacuum after, just only according to around the Electric Field Distribution motion.That is, secondary electron quickens from the state quilt Electric Field Distribution on every side that initial velocity is almost 0 (m/sec).Therefore, as shown in Figure 1, if hypothesis produces electric field Ea is arranged between emitter 22 and collector electrode 32, then secondary electron just along this electric field Ea, determines its launching trajectory.That is, can realize the electron source that straightline propagation is high.The secondary electron that this initial velocity is little be with the coulomb bump of primary electron in obtain energy after in the outside outbound solid of emitter 22 electronics.

, from Fig. 8 also as can be known, has the ENERGY E that is equivalent to primary electron ₀The secondary electron of energy be launched out.This secondary electron is the primary electron that emits from upper electrode 18 electronics (reflection electronic) in emitter 22 near surface scatterings.And the secondary electron that defines described in this specification also comprises described reflection electronic or auger electrons.

The thickness of upper electrode 18 be as thin as a wafer (under～10nm) the situation, the primary electron that emits from upper electrode 18 behind the boundary reflection of upper electrode 18 and emitter 22 towards collector electrode 32.

Here, as shown in Figure 6, if the potential difference between portion's anode and the local negative electrode of setting a trap be V (1a, 1k), the distance between local anode and the local negative electrode is d _A, so, the electric field strength E of electric field centrostigma A _AThere is E with them _A=V (1a, 1k)/d _ARelation.In this case, because between local anode and the local negative electrode apart from d _AVery little, launch necessary electric field strength E so can easily obtain electronics _A(on Fig. 6, solid arrow is represented electric field strength E _AIncrease).This is related to the lower voltage of voltage Vak.

And, if the electronics that continues to carry out from upper electrode 18 is launched, the constituting atom of the emitter 22 that swims after evaporating because of Joule heat is become cation and electronics by the electron ionization that is emitted, the electronics that this ionization produced further makes the ionization such as constituting atom of emitter 22, so pressing exponential function form, electronics increases, like this, in case electronics and cation exist neutrally, just become local plasma.In addition, think that secondary electron also promotes described ionization.Also think and damage upper electrode 18 thus by the cation bump upper electrode 18 that described ionization produces.

But, as shown in Figure 7, at this electronic emission element 12A, the electronics that attracts to come out from upper electrode 18 be used as local anode emitter 22 dipole+utmost point attracts, and makes the electric weight of surface band negative polarity of the emitter 22 nearby of upper electrode 18.As a result, the accelerator (local potential difference) of electronics is relaxed, the electromotive force that reaches secondary is not existed, further make the electric weight of the surface band negative polarity of emitter 22.

Therefore, the positive polarity of the local anode in the dipole weakens, the electric field strength E between local anode and the local negative electrode _ADiminishing, (on Fig. 7, dotted arrow is represented electric field strength E _AReduce), the electronics emission just stops.

Promptly, shown in Fig. 9 A, as the driving voltage Va that applies between upper electrode 18 and the lower electrode 20, if Va1 for example is+100V, Va2 for example is-during 100V, the upper electrode 18 and the voltage variety Δ Vak between the lower electrode 20 at P1 place are that 20V is with interior (being about 10V in the example of Fig. 9 B), almost no change constantly to carry out the peak value of electronics emission.Therefore, almost do not have cation and produce, thereby can prevent the damage of cation, help the long lifetime of electronic emission element 12A upper electrode 18.

Here, as the breakdown voltage of emitter 22, preferably to be higher than 10kV/mm, in this embodiment, when the thickness of emitter 22 is for example made 20 μ m,, can not cause emitter 22 insulation breakdowns even between upper electrode 18 and lower electrode 20, apply-driving voltage of 100V yet.

, clash into emitter 22 once more or make the surface of emitter 22 nearby produce ionization etc., may make this emitter 22 damaged, cause crystal defect, also may become fragile on the structure by the electronics that emits from emitter 22.

Therefore, the dielectric that the evaporating temperature in the most handy vacuum is high constitutes emitter 22, for example also can be by the BaTiO that does not contain Pb ₃Etc. formation.Like this, the constituting atom of emitter 22 just is difficult to because of Joule heat evaporates, and can hinder the ionization of promotion based on electronics.This helps protecting the surface of emitter 22.

In addition, by graphics shape or the current potential that changes collector electrode 32 aptly, or not shown control electrode etc. is configured between emitter 22 and the collector electrode 32, set the Electric Field Distribution between emitter 22 and the collector electrode 32 arbitrarily, control the launching trajectory of secondary electron thus easily, the pack of beam diameter, expansion, distortion are also just easily.

Like this, in electronic emission element 12A, because output is from the secondary electron of emitter 22 emission, so can realize using the long lifetime of light source 10A of electronic emission element 12A and the raising of reliability.And, in this first execution mode because a plurality of electronic emission element 12A are lined up two-dimensionally, so but can realize life-saving and raising reliability area source.

Here, with the difference with display the advantage of area source is described, area source is different from display, and it can be luminous comprehensively all the time, so needn't carry out complicated driving such as for example line scanning, can carry out static drive in the lump.In addition, owing to need not to control the luminous point diameter that the electronics emission causes, so the control electrode that for example plays the condenser lens effect etc. needn't be set between electronic emission element and fluorophor.This is related to the simplification of mechanical structure and circuit structure.

Display must be handled the data-signal that changes at a high speed with picture signal.Therefore, driving voltage becomes the waveform by the complexity of hierarchical modulation.On the other hand, area source needn't be handled the data-signal that changes at a high speed with picture signal, therefore, and can be with simple waveform (pulse period or pulsewidth are respectively certain waveform) as driving voltage.As a result, Power Recovery circuit described later is being connected under the situation of area source, not only can setting the circuit constant, circuit switching timing of this Power Recovery circuit etc. accurately, but also can be substantially 100% power that reclaims driving voltage.

In above-mentioned example, the back side at transparent panel 30 forms collector electrode 32, form fluorophor 34 on the surface of this collector electrode 32 (in the face of the face of upper electrode 18), but the light source 10Aa of first variation that also can be as shown in figure 10 is such, the back side at transparent panel 30 forms fluorophor 34, form collector electrode 32, make it cover this fluorophor 34.In this case, collector electrode 32 is as metal backing.The secondary electron that emits from emitter 22 passes collector electrode 32 and enters fluorophor 34, excites this fluorophor 34.Therefore, the thickness of collector electrode 32 should be able to penetrating electrons, preferably smaller or equal to 100nm.The kinetic energy of secondary electron is big more, and the thickness of collector electrode 32 just can be thick more.

According to such formation, can reach following effect.

(1) do not have under the situation of conductivity at fluorophor 34, can prevent fluorophor 34 charged (bearing), can keep the accelerating field of secondary electron.

(2) collector electrode 32 reflected fluorescent light bodies 34 is luminous, can be effectively with the luminescence emissions of fluorophor 34 to transparent panel 30 sides (light-emitting area side).

(3) can prevent that secondary electron from exceedingly clashing into fluorophor 34, can prevent the deterioration of fluorophor 34 or take place from the gas of fluorophor 34.

In addition, as other variation, as the light source 10Ab of second variation of Figure 11, can on transparent panel 30, form fluorophor 34, in the atmosphere between illuminating part 14A with a plurality of electronic emission element 12A and fluorophor 34, charge into for example mercury grain 40 etc.At this moment, the portions of electronics bump mercury grain 40 from the secondary electron that electronic emission element 12A emits, mercury grain 40 reaches excited state and sends ultraviolet ray 42.This ultraviolet ray 42 is mapped to the fluorophor 34 of periphery, and excited fluophor 34 thus, externally just present light-emitting phosphor.

And as shown in figure 12, drive circuit 16A has timing generating circuit 44 and circuit for generating temperature compensated driving voltage 46.

Timing generating circuit 44 is according to the expression control signal Sc of bright lamp/light-offs and clock Pc generates and driving pulse Pd is stipulated in output the output commutator pulse Pt of usefulness regularly.Specifically, for example as shown in FIG. 13A, described timing generating circuit 44 begins the counting of clock Pc (with reference to Figure 13 B) from the moment that control signal Sc becomes high level (level of representing bright lamp), shown in Figure 13 C, repeat to generate and export be equivalent to the m clock during in the T2 for high level, be equivalent to the n clock during be low level commutator pulse Pt in the T1.Only control signal Sc represent bright lamp during this commutator pulse of output Pt continuously in (Ts during the bright lamp).Control signal Sc be low level (expression turn off the light level) during, promptly turn off the light during in the Tn, from described timing generating circuit 44 signal of output low level only.

Circuit for generating temperature compensated driving voltage 46 is according to the commutator pulse Pt from described timing generating circuit 44, and generation and output should be applied to the upper electrode 18 of each electronic emission element 12A and the driving voltage Va between the lower electrode 20.Specifically, shown in Figure 13 D, this circuit for generating temperature compensated driving voltage 46 timing generating circuit 44 be output as low level during output voltage V a1 in the T1; Timing generating circuit 44 be output as high level during output voltage V a2 in the T2.That is, the commutator pulse Pt that has driving pulse Pd and a timing generating circuit 44 from the driving voltage Va of circuit for generating temperature compensated driving voltage 46 output synchronously, the waveform of appearance continuously.

Therefore, during bright lamp in the Ts, along with the upper electrode 18 of each electronic emission element 12A and applying of the driving pulse Pd between the lower electrode 20, emitting electrons, and excited fluophor continuously 34.As a result, Ts during bright lamp just continues light-emitting phosphor.In addition, Tn during turning off the light owing to do not apply driving pulse Pd between the upper electrode 18 of each electronic emission element 12A and lower electrode 20, so stop the electronics emission from electronic emission element 12A, before the next bright lamp of indication, just continues light-off always.

The preferred implementation of drive circuit 16A then, is described with reference to Figure 14 and Figure 15.As shown in figure 14, the drive circuit 16A of this execution mode also is connected with Power Recovery circuit 50 except above-mentioned timing generating circuit 44 and circuit for generating temperature compensated driving voltage 46.Among this Figure 14, be arranged in the interior whole electronic emission element 12A of illuminating part 14A with a capacitor C representative.Therefore, the side's of capacitor C electrode is meant that the upper electrode 18 of whole electronic emission element 12A, the opposing party's of capacitor C electrode are meant the lower electrode 20 of whole electronic emission element 12A.

If the schematic structure of Power Recovery circuit 50 is described, respectively in parallel the buffer condenser Cf and first series circuit 52 between two electrodes (upper electrode 18 and lower electrode 20) of capacitor C, and then, between capacitor C and buffer condenser Cf, be connected second series circuit 54.

In the example of Figure 14, take a capacitor C is connected the mode of a buffer condenser Cf, but be not limited thereto, also can be to two of capacitor C connections or the buffer condenser Cf more than it, the number of buffer condenser Cf is arbitrarily.

First series circuit 52 is the first switching circuit SW1, electric current to be suppressed the resistance r of usefulness and positive supply 56 (voltage Va1) be together in series and constitute, and second series circuit 54 is second switch circuit SW2 and inductor 58 (inductance L) formation that is together in series.

In addition, circuit for generating temperature compensated driving voltage 46 generates and exports control signal Sc1 and the Sc2 that is used for controlling the first and second switching circuit SW1 and SW2 according to the commutator pulse Pt from timing generating circuit 44.

The action of the drive circuit 16A of present embodiment is described with reference to the oscillogram of Figure 15 here.

At first, before Ts began during the bright lamp, the default first switching circuit SW1 connected (ON), and second switch circuit SW2 disconnects (OFF), and the both end voltage of capacitor C is identical with the voltage Va1 of positive supply 56 substantially.

Then, during entering bright lamp after the Ts during the t1 zero hour of T2, under the control of circuit for generating temperature compensated driving voltage 46, the first switching circuit SW1 disconnects (OFF), second switch circuit SW2 connects (ON).Like this, just begin the sine-wave oscillation of inductor 58 and capacitor C, the resonance oscillation attenuation of beginning capacitor C both end voltage.At this moment, the electric charge of savings in capacitor C just is cushioned capacitor Cf recovery.

The next one constantly t2, be that the waveform (voltage waveform) of capacitor C reaches minimum level (voltage :-Va1=Va2) moment, under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 disconnects (OFF), and capacitor C and buffer condenser Cf system reach high impedance status.Therefore, after this moment t2, the t3 finish time of T2 during voltage Va2 is maintained to.Particularly, as mentioned above, in the moment that drops to voltage Va2 from voltage Va1, from the emitter 22 emission secondary electrons of each electronic emission element 12A, according to this electronics emission, the whole face by transparent panel 30 carries out luminous.

After this, during the t3 finish time of T2, under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 connects (ON).Like this, just begin the sine-wave oscillation of inductor 62 and capacitor C, the resonance of beginning capacitor C both end voltage amplifies.At this moment, the capacitor C charge charging of savings in buffer condenser Cf.

The next one constantly t4, be that the waveform (voltage waveform) of capacitor C reaches maximum level (voltage: in moment Va1), under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 disconnects (OFF), and the first switching circuit SW1 connects (ON).This is constantly after the t4, and voltage Va1 is maintained to the zero hour of T2 during the next one till the t2.

Shown in Figure 13 A～Figure 13 D, with during T2 and during between the continuing phase of T1 during as a stage, during bright lamp, repeat this stage in the Ts.Therefore, in electronic emission element 12A, even oneself stop electronics emission, during T2 also carry out the electronics emission after arriving once more, so from expression in appearance, Ts keeps whole luminous state by transparent panel 30 during whole bright lamp always.That is, before electronics is once launched the luminous delustring that produces, just carry out electronics emission next time, carry out continuously luminous thus.

In addition, shown in Figure 13 A～Figure 13 D, during entering into light-off under the situation of Tn, because voltage Va1 continues to be applied on each electronic emission element 12A, so each electronic emission element 12A does not carry out the electronics emission, therefore, Tn keeps the delustring state during whole light-off.

Like this, by Power Recovery circuit 50 is connected on the drive circuit 16A, can reclaim the power of the cardinal principle 100% of driving voltage, this just helps reducing consumed power.In this embodiment, because first series circuit 52 is set, and timing in accordance with regulations, the both end voltage of capacitor C is waved at voltage Va1, so can avoid following the decay of driving voltage of the consumed power of inductor 58.Certainly, make the both end voltage of capacitor C be in voltage Va1 the zero hour in the use of this light source 10A, after this, also can be only with the ON/OFF action of second switch circuit SW2, that carries out capacitor C alternately discharges and recharges and cushions discharging and recharging of capacitor Cf.

; the light source 10A of the first above-mentioned execution mode applies driving voltage Va between the upper electrode 18 of whole electronic emission element 12A and lower electrode 20; come luminous from illuminating part 14A whole by transparent panel 30 thus; but; in addition; the light source 10Ac of the 3rd variation shown in also can image pattern 16 is such; illuminating part 14A is divided into two groups (first and second groups G1 and G2); when being included in first group of electronic emission element 12A in the G1 when luminous, the power that is included in the electronic emission element 12A in first group of G1 is recycled among the electronic emission element 12A that is included in second group of G2; When being included in second group of electronic emission element 12A in the G2 when luminous, the power that is included in the electronic emission element 12A in second group of G2 is recycled among the electronic emission element 12A that is included in first group of G1.

In this case, electricity consumption container C 1 is represented the electronic emission element 12A that comprises in first group of G1, electricity consumption container C 2 is represented the electronic emission element 12A that comprises in second group of G2, at this moment, shown in Figure 14 bracket, as drive circuit 16A, as long as electricity consumption container C 1 replaces capacitor C, electricity consumption container C 2 replaces buffer condenser Cf and just can.

The action of this drive circuit 16A is described with reference to the oscillogram of Figure 17 here.At first, before Ts began during bright lamp, the default first switching circuit SW1 connected (ON), second switch circuit SW2 disconnects (OFF), and the both end voltage of capacitor C1 is identical with the voltage Va1 of positive supply 56 substantially.

Then, enter during the bright lamp behind the Ts during the T2 t1 zero hour, under the control of circuit for generating temperature compensated driving voltage 46, the first switching circuit SW1 disconnects (OFF), second switch circuit SW2 connects (ON).Like this, the sine-wave oscillation of beginning capacitor C1 and inductor 58 in capacitor C1, the resonance oscillation attenuation of the both end voltage of beginning capacitor C1.At this moment, the electric charge of savings in capacitor C1 reclaimed by capacitor C2.

That is, from the angle of capacitor C2, at described moment t1, the sine-wave oscillation of beginning inductor 58 and capacitor C1, the resonance of the both end voltage of beginning capacitor C2 amplifies.At this moment, the capacitor C2 charge charging of savings in capacitor C1.

The next one constantly t2, be that the waveform (voltage waveform) of capacitor C1 reaches minimum level (voltage :-Va1=Va2) moment, under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 disconnects (OFF), and capacitor C1 and capacitor C2 system reach high impedance status.Therefore, at capacitor C1, after this moment t2, the t3 finish time of T2 during voltage Va2 is maintained at capacitor C2, keeps voltage Va1.

Particularly arrive t2 constantly at moment t1, the both end voltage of capacitor C1 drops sharply to voltage Va2 from voltage Va1, so, as shown in figure 16, be subordinated to the emitter 22 emission secondary electrons of each electronic emission element 12A of first group of G1.According to this electronics emission, undertaken luminous by the zone in the transparent panel 30 corresponding to first group of G1.

T2 is about during launching at the electronics of capacitor C1 during this period, still from the angle of capacitor C2, is T1 between the preparatory stage before the electronics emission.Therefore, preferably set during T2 during the T1=.

After this, during the t3 finish time of T2, under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 connects (ON).Like this, just begin the sine-wave oscillation of inductor 62 and capacitor C1, the resonance of the both end voltage of beginning capacitor C1 amplifies.At this moment, the capacitor C charge charging of savings in buffer condenser Cf.

That is, from the angle of capacitor C2, at described moment t3, the sine-wave oscillation of beginning inductor 58 and capacitor C2, the resonance oscillation attenuation of the both end voltage of beginning capacitor C2.At this moment, the electric charge of savings in capacitor C2 reclaimed by capacitor C1.

The next one constantly t4, be that the waveform (voltage waveform) of capacitor C1 reaches maximum level (voltage: in moment Va1), under the control of circuit for generating temperature compensated driving voltage 46, second switch circuit SW2 disconnects (OFF), and the first switching circuit SW1 connects (ON).Therefore, this is constantly after the t4, and at capacitor C1, voltage Va1 is maintained to the t2 zero hour of T2 during the next one; At capacitor C2, keep voltage Va2.

In addition, to moment t4, the both end voltage of capacitor C2 drops sharply to voltage Va2 from voltage Va1 at moment t3, so, as shown in figure 16, be subordinated to the emitter 22 emission secondary electrons of each electronic emission element 12A of second group of G2.According to this electronics emission, undertaken luminous by the zone in the transparent panel 30 corresponding to second group of G2.

T1 during since moment t3 being.During this period T1 is to carry out between the preparatory stage of next electronics emission usefulness at capacitor C1, but from the angle of capacitor C2, but become relevant electronics emission during T2.

Then, during T2 and during between the continuing phase of T1 (stage) during bright lamp, repeat in the Ts, carry out the electronics emission of each the electronic emission element 12A in first group of G1 and the electronics of each the electronic emission element 12A in second group of G2 thus alternately and launch.Therefore, by T1 during the suitable setting or during cycle of T2, whole luminous state by transparent panel 30 is kept in expression in the Ts during whole bright lamp in appearance.Certainly, also can be consciously during T1 or during T2 set longly, also can recognize luminous difference among luminous and second group of G2 among first group of G1 with end user's eye.

Like this, in the light source 10Ac of the 3rd variation, be also used as the so-called buffer condenser Cf that Power Recovery is used owing to be included in the electronic emission element 12A that comprises in the group beyond the group of carrying out luminous action, so need not to be provided with in addition buffer condenser Cf, can dwindle erection space effectively, reduce consumed power.In addition, the electronic emission element 12A of the electronic emission element 12A of first group of G1 and the second group of G2 configuration that spreads out, it is luminous to access uniform face thus in appearance all the time by certain unit.

In above-mentioned example, illustrated from the situation of each electronic emission element 12A emission certain amount of electrons, but, the drive circuit 16Aa of variation that also can be as shown in figure 18 is such in addition, except that described timing generating circuit 44, circuit for generating temperature compensated driving voltage 46, also be connected with modulation circuit 60.Modulation circuit 60 is according to the circuit of controlling the electron emission amount of each electronic emission element 12A from the dim signal Sh that is arranged on outside light adjusting potentiometer (volume) (not icon).

As the modulation system of modulation circuit 60, four kinds of modulation systems are arranged.First modulation system is, shown in Figure 19 A, and according to the level (voltage level etc.) of dim signal Sh, the mode of the pulsewidth of modulation voltage Va2 shown in Figure 19 B or Figure 19 C.In this case, both can be shown in Figure 19 B, T2 itself between modulation period also can be shown in Figure 19 C, fixing during T2, and τ a during the applying of modulation voltage Va2.As shown in figure 20, the modulation system of Figure 19 C is to utilize pulsewidth and the linear modulation system of brightness of modulation voltage Va2.For example, pulsewidth is fluctuateed from 0 to about 600 μ sec, can make the variation of brightness generation 0～about 1020 (cd/m2) thus.And, because if the pulsewidth of control voltage Va2, so can realize that high-precision grade shows with the digital control of cheapness.

Second modulation system is the method for control sets electrode voltage Vc, as shown in figure 21, is to utilize collector voltage Vc and the linear a kind of modulation system of brightness.Collector voltage Vc is fluctuateed from 4kV to 7kV, can make brightness produce the variation of 0～600 (cd/m2) thus.

The 3rd modulation system is the method for the voltage Va2 (level) of controlling and driving voltage Va, as shown in figure 22, is a kind of voltage Va2 and linear modulation system of brightness utilized.For example, voltage Va2 is fluctuateed from about 118V to 188V, can make brightness produce the variation of 0～1600 (cd/m2) thus.

The 4th modulation system is the method for the voltage Va1 of controlling and driving voltage Va, as shown in figure 23, because voltage Va1 and brightness are non-linear relation, thus be difficult to control, and, must carry out aanalogvoltage control, so must work hard from circuit to voltage Va1.

Therefore, from first～the 4th modulation system, preferably adopt first modulation system of the pulsewidth of modulation voltage Va2.

As shown in Figure 1, the light source 10A of first execution mode is to collector electrode 32 of a plurality of electronic emission element 12A configurations, bias voltage Vc is applied on this collector electrode 32 through resistance R 2, but in addition the light source 10Ad of the 4th variation that also can be as shown in figure 24 is such, arrange for example identical collector electrode 32 (1), 32 (2) with light source 10Ad columns ..., 32 (N), respectively resistance R c1, Rc2 ..., RcN be connected each collector electrode 32 (1), 32 (2) ..., on 32 (N).In this case, can by be connected collector electrode 32 (1), 32 (2) ..., resistance R c1, Rc2 on 32 (N) ..., RcN adjusts the dispersion of fabrication stage, disperse as the brightness of each electronic emission element 12A.

The following adjustment that lightness disperses with reference to Figure 25～Figure 28.

As the record in the document " electronic technology 2000-7, p38～p41: the state-of-the-art technology trend of field-emitter display ", the method that existing reduction disperses is connected emitter by the resistance that electric current is suppressed usefulness and reduces dispersion.

, this method has relation with the electric current and the gate voltage of the emitter of flowing through, and before the brightness that is reduced disperses the only resistance value of usefulness, must repeatedly simulate.

Therefore, in the present embodiment, adopt the collector electrode 32 of the actual arrival of adjustment emitting electrons and the method for the electric field between the upper electrode 18.Like this, can directly adjust brightness and disperse, and can be rapidly and reduce brightness accurately and disperse.

Below specifically describe the reduction method of the brightness dispersion of present embodiment.As shown in figure 25, adjust be connected upper electrode 18 and be used between this upper electrode 18 and lower electrode 20, applying the resistance R k between the negative supply 70 of negative voltage Vk (for example and the identical voltage of above-mentioned voltage Va2) and be connected collector electrode 32 and bias supply 36 (bias voltage Vc) between resistance R c.Among Figure 25, resistance R kc represents that voltage Vkc represents the voltage between the gap based on the resistance in the gap between upper electrode 18 and the collector electrode 32.C represents the electric capacity between upper electrode 18 and the lower electrode 20, and voltage Vak represents the voltage between upper electrode 18 and the lower electrode 20.

Here, suppose two electronic emission element 12A (1) and 12A (2) are arranged, the output characteristic (Vkc-Ikc characteristic) of these two electronic emission element 12A (1) and 12A (2) is when existing dispersion shown in Figure 27, under the situation that does not have described resistance R k and Rc, the electric current change among these two electronic emission element 12A (1) and the 12A (2) is Δ I ₁

But connecting described resistance R k and Rc just can be described electric current change Δ I ₁Be reduced to the electric current change Δ I on the load line 80 always ₂

Can following derivation load line 80.That is, according to structure chart shown in Figure 25, as shown in figure 26 based on the equivalent electric circuit of the electric current I kc between upper electrode 18 and the collector electrode 32 that flows through.

Derive following formula from this equivalence circuit.

Ikc＝(Vk+Vc)/(Rc+Rkc+Rk)

Here, during Rkc=0, the Ikc maximum is so the line that the some Pb of expression Vkc=Vk+Vc on some Pa that represents Ikc=(Vk+Vc)/(Rc+Rk) on the longitudinal axis of Figure 27 and the transverse axis is coupled together just constitutes load line 80.

And Rc+Rk is big more, and electric current I kc is just more little, and still, the brightness between electronic emission element 12A (1) and the 12A (2) disperses also more little.

In addition, be provided with under the situation of not shown control electrode between upper electrode 18 and collector electrode 32, Figure 28 represents based on the collector current Ic of the collector electrode 32 of flowing through and the equivalent electric circuit of the Control current Ig of the control electrode of flowing through.At this moment, resistance R g is connected control electrode and is used for applying between the negative supply 72 of negative voltage Vg between this control electrode and the lower electrode 20.In addition, the resistance R kg of Figure 28 represents the resistance that the gap between upper electrode 18 and the control electrode causes.In addition, in this embodiment, collector current Ic is 60% of cathode current Ik, and Control current Ig is 40% of cathode current Ik.

Derive following formula from the equivalent electric circuit of Figure 28.

Ig＝(Vg+Vk)/(Rg+Rkg+Rk)

As long as derive load line, determine brightness to disperse the voltage Vg and the resistance R g that reach minimum just passable according to this formula.Decide Control current Ig and cathode current Ik by decision voltage Vg and resistance R g, inevitable also determined set electrode current Ic.

In the light source 10A of the first above-mentioned execution mode, has an illuminating part 14A who comprises whole electronic emission element 12A, this illuminating part 14A is connected a drive circuit 16A, but in addition the light source 10Ae of the 5th variation that also can image pattern 29 is such, has two or its above Z1～Z6 of area source portion.In the example of Figure 29, represented to have the situation of six Z1～Z6 of area source portion.Each Z1～Z6 of area source portion arranges a plurality of electronic emission element 12A two-dimensionally, and is connecting drive circuit 16A respectively independently.

Like this, just can control luminous/delustring, and can carry out incremental dimming (digital type light-adjusting) with each Z1 of area source portion～Z6 unit.Particularly be provided with modulation circuit 60 (with reference to Figure 18) among the drive circuit 16A on being connected the Z1～Z6 of area source portion respectively independently, just can distinguish the luminescence distribution of controlling each Z1～Z6 of area source portion independently thus.In a word, except that digital type light-adjusting, light modulation can also be realized simulating, careful light modulation can be carried out.

In the example of Figure 29, represented the identical respectively situation of area of each Z1～Z6 of area source portion, but the area of each Z1～Z6 of area source portion also can be different.For example, in the light source 10Af of the 6th variation shown in Figure 30, the first and the 6th Z1 of area source portion and Z6 are done the rectangle of putting sidewards of the growth length of side respectively; The second and the 5th Z2 of area source portion and Z5 are done the growth limit rectangle that stand on end shorter than the long limit of the first and the 6th Z1 of area source portion and Z6 respectively; Third and fourth Z3 of area source portion and Z4 are done the growth limit rectangle of sidewards putting shorter than the long limit of the first and the 6th Z1 of area source portion and Z6 respectively.

In addition, the light source 10Ag of the 7th variation that also can be as shown in figure 31 is such, be divided into two groups (first group and second group of G1 and G2) respectively being included in a plurality of electronic emission element 12A in each Z1～Z6 of area source portion, among each Z1～Z6 of area source portion, when the electronic emission element 12A in being included in first group was luminous, the power that is included in the electronic emission element 12A in first group of G1 was recycled among the electronic emission element 12A that is included in second group of G2; Be included in electronic emission element 12A in second group of G2 when luminous, the power that is included in the electronic emission element 12A in second group of G2 is recycled among the electronic emission element 12A that is included in first group of G1.

Perhaps, the light source 10Ah of the 8th variation shown in figure 32 is such, also can be divided into two groups (first group and second group of G1 and G2) to six Z1～Z6 of area source portion, when each electronic emission element 12A of the Z1～Z3 of area source portion of relevant first group of G1 was luminous, the power of these electronic emission elements 12A was recycled among the electronic emission element 12A of the Z4～Z6 of area source portion of relevant second group of G2; When each electronic emission element 12A of the Z4～Z6 of area source portion of relevant second group of G2 was luminous, the power of these electronic emission elements 12A was recycled among the electronic emission element 12A of the Z1～Z3 of area source portion of relevant first group of G1.

In the light source 10Ae～10Ah of the 5th～the 8th above-mentioned variation, represent illuminating part 14A is separated into the example of six Z1～Z6 of area source portion, but the number of area source portion can be set arbitrarily.

; as shown in Figure 1; the light source 10A of first execution mode forms a plurality of upper electrodes 18 respectively independently on the surface of an emitter 22; on the back side of emitter 22, form a plurality of lower electrodes 20 respectively independently; thereby form a plurality of electronic emission element 12A, but also can consider other following execution mode in addition.In addition, in Figure 33～Figure 37, omit the statement of collector electrode 32 or fluorophor 34.

Promptly, the light source 10Ai of the 9th variation of Figure 33 forms a plurality of upper electrodes 18 respectively independently on the surface of an emitter 22, on the back side of emitter 22, form a lower electrode 20 (public lower electrode), form a plurality of electronic emission element 12A thus.

The light source 10Aj of the tenth variation of Figure 34 forms (～10nm) a upper electrode 18 (public upper electrode) as thin as a wafer on the surface of an emitter 22, the a plurality of lower electrodes 20 of independent respectively formation form a plurality of electronic emission element 12A thus on the back side of emitter 22.

The light source 10Ak of the 11 variation of Figure 35 forms a plurality of lower electrodes 20 respectively independently on substrate 90, form an emitter 22 again and cover these lower electrodes 20, on emitter 22, form a plurality of upper electrodes 18 then respectively independently, form a plurality of electronic emission element 12A thus.Each upper electrode 18 is clipped in emitter 22 therebetween and forms on bottom electrode corresponding 20 respectively.

The light source 10A1 of the 12 variation of Figure 36 forms a lower electrode 20 on substrate 90, form an emitter 22 again and cover this lower electrode 20, on emitter 22, form a plurality of upper electrodes 18 then respectively independently, form a plurality of electronic emission element 12A thus.

The light source 10Am of the 13 variation of Figure 37 forms a plurality of lower electrodes 20 respectively independently on substrate 90, form an emitter 22 again and cover these lower electrodes 20, form a upper electrode 18 as thin as a wafer at emitter 22 then, form a plurality of electronic emission element 12A thus.

The following light source 10B that second execution mode is described with reference to Figure 38～Figure 77.In addition, with the same symbol of the corresponding part mark of first execution mode, omit the explanation of its repetition.

As shown in figure 38, the electronic emission element 12B of the light source 10B of second execution mode has above-mentioned emitter 22, upper electrode 18, lower electrode 20 and apply driving voltage Va pulse generation source 100 between upper electrode 18 and lower electrode 20.

Upper electrode 18 has a plurality of breakthrough parts 102 that emitter 22 exposes.Particularly be formed with concavo-convex 104 based on dielectric grain boundary on the surface of emitter 22, the breakthrough part 102 of upper electrode 18 is formed on the part corresponding to the recess 106 of described dielectric grain boundary.In the example of Figure 38, express the situation that forms a breakthrough part 102 corresponding to a recess 106, but also can form a breakthrough part 102 corresponding to a plurality of recesses 106.The dielectric particle diameter that constitutes emitter 22 in the scope of 0.1 μ m～10 μ m for well, 2 μ m～7 μ m preferably.In the example of Figure 38, the particle diameter of power taking medium is 3 μ m.

And then as shown in figure 39, in this second execution mode, the face 108a in the face of emitter 22 in the perimembranous 108 of the breakthrough part 102 in the upper electrode 18 leaves emitter 22.That is, be formed with gap 110 between face 108a that faces emitter 22 in the perimembranous 108 of the breakthrough part 102 in the upper electrode 18 and the emitter 22, the perimembranous 108 of the breakthrough part 102 in the upper electrode 18 becomes eaves shape (flange-like).Therefore, in the following description, " perimembranous 108 of the breakthrough part 102 in the upper electrode 18 " recorded and narrated is " the eaves portion 108 of upper electrode 18 ".In the example of Figure 38, Figure 39, Figure 41 A, Figure 41 B, Figure 42 A, Figure 42 B, Figure 44, Figure 46～Figure 49, Figure 54,, but be not limited thereto shape with the semicircle section of representing concavo-convex 104 protuberance 112 of dielectric grain boundary.

In addition, in this second execution mode, the thickness t of getting upper electrode 18 is 0.01 μ m≤t≤10 μ m; Get emitter 22 top, be that the maximum angle θ of the angle that constitutes of the following 108a of eaves portion 108 of surface (also being the internal face of recess 106) and the upper electrode 18 of the protuberance 112 of dielectric grain boundary is 1 °≤θ≤60 °.In addition, the largest interval d along vertical direction between the following 108a of the eaves portion 108 of the surface of the protuberance 112 of dielectric grain boundary of emitter 22 (internal face of recess 106) and upper electrode 18 is taken as 0 μ m＜d≤10 μ m.

And then, in this second execution mode, the shape of breakthrough part 102, particularly as shown in figure 40 the shape of seeing from above that is shaped as hole 114 are for example as circular, oval, the oblong shape that comprises curved portion or picture quadrangle, leg-of-mutton polygon.In the example of Figure 40, expression is with the situation of circle as the shape in hole 114.

In this case, the average diameter in hole 114 is taken as more than or equal to 0.1 μ m smaller or equal to 10 μ m.This average diameter is represented the average length by the length of many line segments that have nothing in common with each other at 114 centers, hole.

In addition, the constituent material of emitter 22 is because of identical with the first above-mentioned execution mode, so omit its explanation.

Method as forming emitter 22 can adopt various film forming methods such as various thick film forming methods such as wire mark method, infusion process, coating process, electrophoresis, atomizing sedimentation or ion beam method, sputtering method, vacuum vapour deposition, ion plating, chemical vapor-phase growing method (CVD), plating.Good especially method is as emitter 22, forms the material of piezoelectric/electrostrictive material powdered, floods low-melting glass or sol particles again.Just can carry out the film formation down of 700 ℃ or 600 ℃ or its following low temperature in this way.

Upper electrode 18 preferably uses the organic metal paste that obtains film after sintering, for example material such as platinum resin acid paste.In addition, preferably use the oxide electrode that suppresses polarization reversal fatigue, for example ruthenium-oxide (RuO ₂), yttrium oxide (IrO ₂), ruthenic acid strontium (SrRuO ₃), La _1-xSr _xCoO ₃(for example x=0.3 or 0.5), La _1-xCa _xMnO ₃(for example x=0.2), La _1-xCa _xMn _1-yCo _yO ₃(for example x=0.2 y=0.05), perhaps is blended into the material that forms in the platinum resin acid paste to them.

In addition, as upper electrode 18, the aggregate 122 of the conductive material 120 of the material 116 that preferably uses the aggregate 118 of the material with a plurality of lepidiod shapes 116 (for example graphite) shown in Figure 41 A and Figure 41 B or have a plurality of lepidiod shapes comprising shown in Figure 42 A and Figure 42 B.In this case, be not to cover the surface of emitter 22 fully, but a plurality of breakthrough parts 102 that expose emitter 22 parts are set, will face the part of breakthrough part 102 in the emitter 22 as electron emission region with described aggregate 118 or aggregate 122.

Upper electrode 18 can use above-mentioned material to form according to common film formation methods such as various film forming methods such as various thick film forming methods such as wire mark method, gunite, coating method, infusion process, coating process, electrophoresis or sputtering method, ion beam method, vacuum vapour deposition, ion plating, chemical vapor-phase growing method (CVD), plating, and the most handy the former thick film forming method forms.

On the other hand, lower electrode 20 uses the material with conductivity, and for example metal is made of platinum, molybdenum, tungsten etc.In addition, by high-temperature oxydation atmosphere is had repellence the mixture etc. of mixture, insulating ceramics and alloy of conductor, for example metal simple-substance, alloy, insulating ceramics and metal simple-substance constitute, comparatively suitable is by high-melting-point noble metals such as platinum, iridium, palladium, rhodium, molybdenums or with silver-palladium, silver-platinum, platinum-palladium is that the material of principal component or the cermet material of platinum and ceramic material constitute.More suitable is is that the material of main component constitutes by platinum or with the alloy of platinum system only.

In addition, as lower electrode 20, also can use carbon, graphite based material.In addition, add the volume ratio preferably about 5～30% of the ceramic material in the electrode material to.Certainly, also can use the material same with above-mentioned upper electrode 18.

Lower electrode 20 preferably forms with above-mentioned thick film forming method.The thickness of lower electrode 20 smaller or equal to 20 μ m just can, be preferably less than and equal 5 μ m.

Heat-treat (sintering processes) when forming emitter 22, upper electrode 18 and lower electrode 20 respectively and just can be made of one structure.

Temperature as emitter 22, upper electrode 18 and lower electrode 20 being made of one the sintering processes of structure can be taken as 500 ℃～1400 ℃ scope, preferably is taken as 1000 ℃～1400 ℃ scope.And then when membranaceous emitter 22 was heat-treated, preferably the evaporation source with emitter 22 carried out carrying out sintering processes when atmosphere is controlled, so that be unlikely to make the composition instability of emitter 22 when high temperature.

By carrying out sintering processes, especially, make the film that constitutes upper electrode 18 be retracted to thickness 0.1 μ m from thickness 10 μ m, form a plurality of holes simultaneously, the result, as shown in figure 38, on upper electrode 18, form a plurality of breakthrough parts 102, and form the eaves shape in the perimembranous 108 of breakthrough part 102.Certainly, also in advance (before the sintering) undertaken graphically carrying out sintering then by etching (Wet-type etching, dry-etching) or the film peeled off constituting upper electrode 18.In this case, as described later,, can easily form notch geometry or slit (slit) shape as breakthrough part 102.

In addition, cover emitter 22, also can not adopt the method for carrying out sintering in sintering atmosphere is directly exposed on the surface of this emitter 22 with suitable material.

The following describes the electronics emission principle of electronic emission element 12B.At first, between upper electrode 18 and lower electrode 20, apply driving voltage Va.This driving voltage Va is defined as sharply being changed to along with the voltage level that is higher or lower than reference voltage (for example 0V) through associating of time the voltage of the level that is below or above reference voltage for example as pulse voltage or alternating voltage.

In addition, the place that contacts of the medium (for example vacuum) on emitter 22, around upper electrode 18 and this electronic emission element 12B is formed with triple tandem areas.Here, so-called triple tandem area is defined as the electric field that upper electrode 18, emitter 22 form with contacting of vacuum and concentrates portion.In addition, also comprise the three remittance nodes that upper electrode 18, emitter 22 and vacuum exist as a point at described triple tandem areas.Vacuum degree in the atmosphere preferably 10 ²～10 ^-6Handkerchief, 10 ^-3～10 ^-5Handkerchief is better.

In second execution mode, triple tandem areas are formed on the eaves portion 108 of upper electrode 18 or the surrounding edge portion of upper electrode 18.In a single day therefore between upper electrode 18 and lower electrode 20, apply aforesaid driving voltage Va, just produce electric field at above-mentioned triple tandem areas and concentrate.

The first electronics radiation pattern of electronic emission element 12B is described with reference to Figure 43 and Figure 44 here.T1 (phase I) between first period of output of Figure 43 is applied to the voltage V2 that is lower than reference voltage (being 0V) here on the upper electrode 18, and the voltage V1 that is higher than reference voltage is applied on the lower electrode 20.Between this first period of output in the T1, producing electric field at above-mentioned triple tandem areas concentrates, carry out the electronics emission from upper electrode 18 to emitter 22, for example, electronics is put aside the part that the breakthrough part 102 from upper electrode 18 in emitter 22 exposes or the surrounding edge portion part nearby of upper electrode 18.That is, emitter 22 is charged.At this moment, upper electrode 18 plays the electronics supply source.

T2 (second stage) between next second period of output, the level of driving voltage Va is die-offed, promptly, in case the voltage V1 higher than reference voltage is applied on the upper electrode 18 the voltage V2 that is lower than reference voltage is applied on the lower electrode 20, specifically, corresponding to the surrounding edge portion of the part of the breakthrough part 102 of upper electrode 18 or upper electrode 18 nearby the electronics of carried charge dipole (surface of emitter 22 presents negative polarity) that the emitter 22 of polarization reversal just taken place round about drive out of from emitter 22, as shown in figure 44, electronics is just by emitting in the described part of putting aside electronics of breakthrough part 102 from emitter 22.Certainly, also nearby launch electronics from the peripheral part of upper electrode 18.

Then, the second electronics radiation pattern is described.At first, T1 (phase I) between first period of output of Figure 45 is applied to the voltage V3 that is higher than reference voltage on the upper electrode 18, and the voltage V4 that is lower than reference voltage is applied on the lower electrode 20.Between this first period of output in the T1, carry out the preparation (for example towards the polarization of a direction of emitter 22 etc.) of electronics emission.T2 (second stage) between next second period of output, driving voltage Va level is die-offed, promptly, in case the voltage V4 that is lower than reference voltage is applied on the upper electrode 18 the voltage V3 that is higher than reference voltage is applied on the lower electrode 20, specifically, just produce electric field and concentrate, concentrate according to this electric field at above-mentioned triple tandem areas, primary electron emits from upper electrode 18, and near the part of exposing from breakthrough part 102 and the peripheral part of upper electrode 18 of bump in the emitter 22.As shown in figure 46, secondary electron (reflection electronic that comprises primary electron) just emits from the part of primary electron bump like this.That is, the initial stage of T2 between second period of output, secondary electron nearby emits from the peripheral part of described breakthrough part 102 and upper electrode 18.

And, in this electronic emission element 12B, owing on upper electrode 18, be formed with a plurality of breakthrough parts 102, so electronics nearby emits equably from the peripheral part of breakthrough part 102 and upper electrode 18, reduced the dispersion of whole electron emission characteristic, and carry out the control that electronics is launched easily, improved electronic transmitting efficiency simultaneously.

In addition, in second execution mode, owing between the eaves portion 108 of upper electrode 18 and emitter 22, be formed with gap 110, so when having applied driving voltage Va, it is concentrated to be easy to generate electric field in these gap 110 parts.This just is related to the raising of electronic transmitting efficiency, can realize the lower voltage (the electronics emission under the low level) of driving voltage.

As mentioned above, in second execution mode,, become big so concentrate at the electric field of the part in above-mentioned gap 110 because upper electrode 18 is formed with eaves portion 108 in the perimembranous of breakthrough part 102, correspondingly, electronics also emits from the eaves portion 108 of upper electrode 18 easily.This is related to height output, the high efficiency of electronics emission, can realize the lower voltage of driving voltage Va.Like this, can realize a plurality of electronic emission element 12B arranged side by side and the high brightnessization of the light source 10B of second execution mode that constitutes.

In addition, because gate electrode (control electrode, focused electron lens etc.) plays in the eaves portion 108 of upper electrode 18, so no matter be the still second electronics radiation pattern (make primary electron from upper electrode 18 clash into emitter 22 and launch secondary electron the mode) straightline propagation that can both improve emitting electrons of the above-mentioned first electronics radiation pattern (mode of the electronics of emission savings emitter 22 in).Constitute at a plurality of electronic emission element 12B arranged side by side under the situation of the electron source of display for example, this crosstalks for reduction is very favourable.

Like this, in the light source 10B of second execution mode, can be easy to generate high electric field and concentrate, and, can increase electronics emission place, can realize height output, the high efficiency of electronics emission, can also realize low voltage drive (low consumpting power).

Particularly in second execution mode, at least on emitter 22, be formed with based on concavo-convex 104 of dielectric grain boundary, upper electrode 18 is formed with breakthrough part 102 in the part corresponding to the recess 106 of dielectric grain boundary, so, the eaves portion 108 that can realize upper electrode 18 simply.

In addition, because above emitter 22, be that the maximum angle θ of the angle that constitutes of the following 108a of eaves portion 108 of surface (internal face of recess 106) and the upper electrode 18 of the protuberance 112 of dielectric grain boundary makes 1 °≤θ≤60 °, the largest interval d of the vertical direction between the following 108a of the eaves portion 108 of the surface of the protuberance 112 of dielectric grain boundary of emitter 22 (internal face of recess 106) and upper electrode 18 is made 0 μ m＜d≤10 μ m, so according to such formation, the electric field intensity of 110 parts can be strengthened more, the height output of electronics emission can be realized effectively in the gap, the lower voltage of high efficiency and driving voltage.

In addition, in this second execution mode, breakthrough part 102 is made to become the shape in hole 114.As shown in figure 39, in emitter 22, formed the part (first) 124 under the upper electrode 18 and changed according to being applied to part that driving voltage Va between upper electrode 18 and the lower electrode 20 (with reference to Figure 38) polarization reversal takes place or change polarization corresponding to the degree of concentrating with level or the electric field of driving voltage Va from the part (second portion) 126, particularly second portion 126 in the zone of the inside of the interior circumferential breakthrough part 102 of breakthrough part 102.Therefore, in this second execution mode, the average diameter of getting hole 114 for more than or equal to 0.1 μ m smaller or equal to 10 μ m.If this scope, the emission of the electronics that emits by breakthrough part 102 distributes and does not almost disperse, expeditiously emitting electrons.

In addition, under the situation of the average diameter of getting hole 114 less than 0.1 μ m, the zone of savings electronics narrows down, and the amount of institute's electrons emitted reduces.Certainly, can consider to be provided with a plurality of holes 114, still, having any problem property, and manufacturing cost probably can rise.Surpass 10 μ m if get the average diameter in hole 114, then breakthrough part 102 from the part that described breakthrough part 102 exposes, the ratio (occupation rate) of the part of emitting electrons (second portion) 126 reduces, the emission effciency of electronics descends.

Section configuration as the eaves portion 108 of upper electrode 18, both can be as shown in figure 39, the shape of extending with following all along continuous straight runs above making, also can be as shown in figure 47, the following 108a that makes eaves portion 108 be substantially level and the upper end of eaves portion 108 towards the shape of top projection.In addition, as shown in figure 48, square neck is oblique up at leisure towards the center of breakthrough part 102 also can to make the following 108a of eaves portion 108; As shown in figure 49, square neck is oblique down at leisure towards the center of breakthrough part 102 also can to make the following 108a of eaves portion 108.The example of Figure 47 can improve the function as gate electrode, in the example of Figure 49, because gap 110 parts narrow down, concentrates so more be easy to generate electric field, can improve the output and the emission effciency of electronics emission.

In addition, in this second execution mode, as shown in figure 50, in the electronic work, between upper electrode 18 and lower electrode 20, formed based on the capacitor C1 of emitter 22 with based on the aggregate of a plurality of capacitor Ca in each gap 110.That is,, in the equivalent electric circuit, be connected on the capacitor C2 based on aggregate based on the capacitor C1 of emitter 22 based on a capacitor C2 of a plurality of capacitor Ca formation parallel with one another in each gap 110.

In fact, be not on the capacitor C2 that is connected on based on aggregate based on the capacitor C1 of emitter 22, but the capacitor composition that is together in series is with the formation number of the breakthrough part 102 of upper electrode 18 or whole formation area etc. are changed so unalterablely.

Here, shown in Figure 51, for example suppose the situation of connecting with capacitor C2, carry out calculation of capacity based on aggregate based on 25% among the capacitor C1 of emitter 22.At first, because gap 110 parts are vacuum, so its dielectric constant is 1.And the largest interval d that establishes gap 110 is that the area of 0.1 μ m, gap 110 parts is that the number in S=1 μ m * 1 μ m, gap 110 is 10,000.In addition, if establish that the dielectric constant of emitter 22 is 2000, the thickness of emitter 22 is 20 μ m, upper electrode 18 and the area of facing mutually of lower electrode 20 are 200 μ m * 200 μ m, then be 0.885pF, be 35.4pF based on the capacitance of the capacitor C1 of emitter 22 based on the capacitance of the capacitor C2 of aggregate.And, among the capacitor C1 based on emitter 22, the part of connecting with capacitor C2 based on aggregate is whole 25% o'clock, and this series connection capacitance (comprising the capacitance based on the capacitor C2 of aggregate) partly is exactly 0.805pF, and the capacitance of remainder is 26.6pF.

Because the part of these series connection is in parallel with remainder, so the integral capacitor amount is 27.5pF.This capacitance be based on emitter 22 capacitor C1 capacitance 35.4pF 78%.In a word, the integral capacitor amount is less than the capacitance based on the capacitor C1 of emitter 22.

Like this, for aggregate based on the capacitor Ca in a plurality of gaps 110, capacitance based on the capacitor Ca in gap 110 is less relatively, by dividing potential drop based on the capacitor C1 of emitter 22, almost whole driving voltage Va is applied on the gap 110, can realize the height outputization of electronics emission in each gap 110.

In addition, owing to be connected on the capacitor C1 based on emitter 22, so the integral capacitor amount is less than the capacitance based on the capacitor C1 of emitter 22 based on the capacitor C2 of aggregate.Thus, can access the electronics emission is high output and the little good characteristic of total consumption power.

Below, three variation of electronic emission element 12B of the light source 10B of the second above-mentioned execution mode are described with reference to Figure 52～Figure 54.

At first, shown in Figure 52, the shape of the breakthrough part 102 of the electronic emission element 12Ba of first variation, the shape of particularly seeing from above are the shapes of breach 128, and this point is different from above-mentioned execution mode.As the shape of breach 128, shown in Figure 52, the breach 130 of the broach shape that preferably a plurality of breach 128 form continuously.In this case, can reduce the dispersion of the emission distribution of the electronics that emits by breakthrough part 102, help emitting electrons expeditiously.Particularly, preferably the mean breadth of breach 128 is made more than or equal to 0.1 μ m smaller or equal to 10 μ m.This mean breadth is represented the mean value perpendicular to the length of many line segments that have nothing in common with each other of the center line of breach 128.

Shown in Figure 53, the shape of the breakthrough part 102 of the electronic emission element 12Bb of second variation, the shape of particularly seeing from above are slits 132, and this point is different from above-mentioned execution mode.Here, so-called slit 132 is that the length of long axis direction (vertically) is 10 times or its above shape of the length of short-axis direction (laterally).Therefore, can just be defined as the length of long axis direction (vertically) less than 10 times shape of the length of short-axis direction (laterally) shape of hole 114 (with reference to Figure 40).In addition, as slit 132, a plurality of holes 114 that also comprise connection couple together the shape that forms.In this case, the mean breadth of slit 132 is preferably more than or equal to 0.1 μ m smaller or equal to 10 μ m.Because this helps reducing the dispersion by the emission distribution of breakthrough part 102 electrons emitted, and helps emitting electrons expeditiously.This mean breadth is represented the mean value perpendicular to the length of many line segments that have nothing in common with each other of the center line of slit 132.

Shown in Figure 54, on the emitter 22 of the electronic emission element 12Bc of the 3rd variation among corresponding to the part of breakthrough part 102, for example have floating electrode 134 in the recess 106 of dielectric grain boundary, this point is different from above-mentioned execution mode.In this case, because floating electrode 134 also becomes the electronics supply source, so, can be transmitted into the outside to a plurality of electronics by breakthrough part 102 at the launching phase (T2 (with reference to Figure 43) between second period of output in the first above-mentioned electronics radiation pattern) of electronics.In this case, think that from the electronics of floating electrode 134 emission is to be concentrated by the electric field of triple tandem areas of floating electrode 134/ dielectric/vacuum to cause.

Here, the characteristic of electronic emission element 12B of the light source 10B of second execution mode is described, specifies voltage-quantity of electric charge characteristic (voltage-amount of polarization characteristic).

Shown in the characteristic of Figure 55, in a vacuum, the characteristic curve of this electronic emission element 12B is to be the asymmetrical magnetic hysteresis loop of benchmark with reference voltage=0 (V).

If this characteristic is described, at first, when the part of the emitting electrons in the emitter 22 is defined as electron emission part, locate at the some p1 (initial condition) that has applied reference voltage, be in the state that described electron emission part is not almost put aside electronics.After this, in case apply negative voltage, in described electron emission part, the positive charge amount that the dipole of polarization reversal has taken place emitter 22 increases, and thereupon, causes launching to the electronics of electron emission part from upper electrode 18 in the phase I, and electronics is put aside.Make negative voltage level when negative direction increases down, along with electronics savings to described electron emission part, some p2 place at certain negative voltage, positive and negative charge amount reaches poised state, if make negative voltage level continue to increase to negative direction, then the amount of savings of electronics further increases, and thereupon, reaches the state of negative charge amount more than the positive charge amount.At a p3 place, reach electronics savings saturation condition.The negative charge amount here is the negative charge amount sum of the original remaining amount of electrons put aside and emitter 22 dipole that polarization reversal has taken place.

After this, reduce negative voltage level, surpass reference voltage then, in case apply positive voltage, at a p4 place, the electronics emission of beginning second stage.If positive voltage is increased down to positive direction, then electron emission amount increases, and at a p5 place, positive and negative charge amount reaches poised state.In addition, at a p6 place, the electronics of being put aside is almost all launched, and the difference of positive and negative charge amount is identical with initial condition substantially.That is, put aside electronics hardly, the negative electrical charge of the dipole that only is emitter 22 polarization reversals appears at electron emission part.

This characteristic has following feature.

(1) establishing negative voltage that positive and negative charge amount reaches the some p2 place of poised state is that the positive voltage at V1, some p5 place is V2, so

|V1|＜|V2|

(2) say so 1.5 in more detail * | V1|＜| V2|

(3) the set up an office ratio of variation of p2 place positive charge amount and negative charge amount is that the ratio of the variation of Δ Q1/ Δ V1, some p5 place's positive charge amount and negative charge amount is Δ Q2/ Δ V2, so

(ΔQ1/ΔV1)＞(ΔQ2/ΔV2)

(4) establishing the voltage that reaches electronics savings saturation condition is that the voltage that V3, beginning electronics are launched is V4, so

1≤|V4|/|V3|≤1.5

Then, the characteristic of explanation Figure 55 on the position of voltage one amount of polarization characteristic.Under initial condition, emitter 22 is along a direction polarization, and the situation that the negative pole of for example supposing dipole is in the state (with reference to Figure 56 A) above emitter 22 describes.

At first, shown in Figure 55, locate at the some p1 (initial condition) that applies reference voltage (for example 0V), shown in Figure 56 A, be in the state of negative pole above emitter 22 of dipole, become the state of on emitter 22, almost not putting aside electronics thus.

After this, in case apply negative voltage and this negative voltage is increased down to negative direction, when surpassing negative coercive voltage (with reference to the some p2 of Figure 55), the beginning polarization reversal at the some p3 of Figure 55, reaches whole polarization reversals (with reference to Figure 56 B).According to this polarization reversal, producing electric field at above-mentioned triple tandem areas concentrates, cause the phase I from upper electrode 18 to the emission of the electronics of emitter 22, for example electronics is put aside the part that the breakthrough part 102 from upper electrode 18 in emitter 22 exposes or the surrounding edge portion part (with reference to Figure 56 C) nearby of upper electrode 18.The part emitting electrons of to emitter 22, exposing from upper electrode 18 (internal emission) particularly from the breakthrough part 102 of upper electrode 18.And reach the savings saturation condition of electronics at the some p3 of Figure 55.

After this, reduce negative voltage level, surpass reference voltage then,, then reach the top electriferous state (with reference to Figure 57 A) that certain level is kept emitter 22 before always in case add positive voltage.If further improve the level of positive voltage, then just in the some p4 front of Figure 55, the negative pole of generation dipole begins the zone (with reference to Figure 57 B) above emitter 22, further improve level, after the some p4 of Figure 55, according to the Coulomb repulsion that the negative pole of dipole causes, beginning emitting electrons (with reference to Figure 57 C).If continue to improve this positive voltage to positive direction, then electron emission amount increases, and surpasses positive coercive voltage (some p5) time to rise, the polarization zone of counter-rotating once more enlarges, at a p6 place, the electronics of being put aside is almost all launched, and the amount of polarization of this moment is identical with the amount of polarization of initial condition substantially.

The characteristic of this electronic emission element 12B has following feature.

(A) establishing negative coercive voltage is that v1, positive coercive voltage are v2, so

|v1|＜|v2|

(B) say so 1.5 in more detail * | v1|＜| v2|

The variation ratio of the polarization when (C) facility adds negative coercive voltage v1 is Δ q1/ Δ v1, the variation ratio of the polarization when applying positive coercive voltage v2 is Δ q2/ Δ v2, so

(Δq1/Δv1)＞(Δq2/Δv2)

(D) establishing the voltage that reaches electronics savings saturation condition is that the voltage that v3, beginning electronics are launched is v4, so

1≤|v4|/|v3|≤1.5

Because this electronic emission element 12B has aforesaid characteristic, so can be applicable to simply that having a plurality of electronic emission element 12B and the basis of arranging by a plurality of pixels launches the light source 10B that carries out the second luminous execution mode from the electronics of each electronic emission element 12B.

Below, the light source 10B that uses above-mentioned electronic emission element 12B to constitute is described.

The light source 10B of this second execution mode is according to the light source that carries out the display that images such as backlight that LCD uses show, shown in Figure 58, has the drive circuit 16B that a plurality of electronic emission element 12B for example are arranged in rectangular or jagged illuminating part 14B corresponding to light-emitting components such as pixels and are used for driving this illuminating part 14B.In this case, both can distribute an electronic emission element 12B, also can distribute a plurality of electronic emission element 12B a light-emitting component to a light-emitting component.In this execution mode, for the purpose of illustrative ease, illustrate that supposition distributes the situation of an electronic emission element 12B to a light-emitting component.

This drive circuit 16B is equipped with many capable selection wires 144 that are used for to illuminating part 14B selection row, also is equipped with the many signal line 146 that are used for to same illuminating part 14B supply data-signal Sd.

And then this drive circuit 16B has: for example select the row of electronic emission element 12B to select circuit 148 with 1 behavior unit sequence thereby row selection wire 144 is optionally supplied with selection signal Ss; The parallel signal supply circuit 150 that outputs to holding wire 146 and supply with data-signal Sd to the row (selecting row) of selecting circuit 148 to select by row respectively of data-signal Sd; Signal control circuit 152 according to the control signal Sv that is imported (picture intelligence etc.) and synchronizing signal Sc control row selection circuit 148 and signal supply circuit 150.

Power circuit 154 (for example 50V or 0V) connects to be expert to be selected on circuit 148 and the signal supply circuit 150, the negative line of selecting 154 of circuit 148 and power circuits of particularly being expert at and GND () between be connected with the pulse power 156.The pulse power 156 output be reference voltage (for example 50V) and be voltage (pulse-like voltage waveform for example-400V) in the Th between light emission period in the Td during electric charge savings described later.

Row is selected circuit 148 Td during the electric charge savings, selects signal Ss to selecting line output, to non-selection line output non-select signal Sn.In addition, row is selected circuit 148 Th between light emission period, and output is (certain voltage that for example-400V) stacks up (for example-350V) with voltage from the pulse power 156 from the supply voltage (for example 50V) of power circuit 154.

Signal supply circuit 150 has pulse generation circuit 158 and modulation circuit 160.Pulse generation circuit 158 is Td during the electric charge savings, generates and export the pulse signal Sp with certain amplitude (for example 50V), Th between light emission period, output reference voltage (for example 0V) by certain pulse period.

Modulation circuit 160 is Td during the electric charge savings, to pulse signal Sp from pulse generation circuit 158, carry out amplitude modulation according to the intensity level of the light-emitting component of selecting row respectively, and be output as respectively about selecting the data-signal Sd of capable light-emitting component, Th between light emission period, former state output is from the reference voltage of pulse generation circuit 158.The supply to modulation circuit 160 of the intensity level of these timing controlled and selected a plurality of light-emitting components all is to be undertaken by signal supply circuit 150.

For example, three examples shown in Figure 59 A～Figure 59 C are such, and under the low situation of intensity level, the amplitude of pulse signal Sp is low level Vsl (with reference to Figure 59 A); Under the medium situation of intensity level, the amplitude of pulse signal Sp is middle level Vsm (with reference to Figure 59 B); Under the high situation of intensity level, the amplitude of pulse signal Sp is high level Vsh (with reference to Figure 59 C).In this example, example goes out to be divided into three grades example, and under the situation that is applicable to light source 10B, according to the intensity level of light-emitting component, for example by 128 grades or 256 grades, pulse signals Sp carries out amplitude modulation.

The variation of signal supply circuit 150 is described with reference to Figure 60～Figure 61 C here.

Shown in Figure 60, the signal supply circuit 150a of variation has pulse generation circuit 162 and pulse-width modulation circuit 164.Pulse generation circuit 162 Td during the electric charge savings generates and exports the level continually varying pulse signal Spa (dotting among Figure 61 A～Figure 61 C) of forward position waveform in the voltage waveform (representing with solid line among Figure 61 A～Figure 61 C) that is applied on the electronic emission element 12B, Th output reference voltage between light emission period.In addition, pulse-width modulation circuit 164 during electric charge savings Td to pulsewidth Wp (with reference to Figure 61 A～Figure 61 C) from the pulse signal Spa of pulse generation circuit 162, basis is modulated about the intensity level of selecting capable light-emitting component respectively, and is output as the data-signal Sd about the light-emitting component of selecting row respectively.The output of Th former state is from the reference voltage of pulse generation circuit 162 between light emission period.In this case, the supply to pulse-width modulation circuit 164 of the intensity level of these timing controlled and selected a plurality of light-emitting components also is to be undertaken by signal supply circuit 150a.

For example, three examples shown in Figure 61 A～Figure 61 C are such, and under the low situation of intensity level, the pulsewidth Wp of pulse signal Spa is narrow, and the amplitude of essence is low level Vsl (with reference to Figure 61 A); Under the medium situation of intensity level, the pulsewidth Wp of pulse signal Spa is a medium-width, and the amplitude of essence is middle level Vsm (with reference to Figure 61 B); Under the high situation of intensity level, the pulsewidth Wp of pulse signal Spa is wide, and the amplitude of essence is high level Vsh (with reference to Figure 61 C).Here, example goes out to be divided into three grades example, but is applicable under the situation of light source 10B, and according to the intensity level of light-emitting component, for example by 128 grades or 256 grades, pulse signals Spa carries out pulse-width modulation.

Here, when the example of the three kinds of amplitude modulation of the pulse signal Sp shown in Figure 59 A～Figure 59 C and example to the three kinds of pulse-width modulations of the pulse signal Spa shown in Figure 61 A～Figure 61 C being associated the variation of the performance plot under the situation of observing the level that changes the negative voltage that relevant above-mentioned electronics puts aside, shown in Figure 62 A, under the level Vsl of the negative voltage shown in Figure 59 A and Figure 61 A, the amount of being put aside the electronics in electronic emission element 12B is few; Shown in Figure 62 B, under the level Vsm of the negative voltage shown in Figure 59 B and Figure 61 B, the amount of the electronics of being put aside is moderate; Shown in Figure 62 C, under the level Vsh of the negative voltage shown in Figure 59 C and Figure 61 C, the amount of the electronics of being put aside is many, is saturation condition substantially.

But shown in Figure 62 A～Figure 62 C, the voltage level of the some p4 of beginning electronics emission much at one.That is, behind the savings electronics, arrive till the voltage level shown in the some p4 even apply change in voltage, the amount of savings of electronics does not almost change yet, and brings into play the memory effect as can be known.

In addition, utilizing under the situation of this electronic emission element 12B as the light-emitting component of light source 10B, shown in Figure 63, the transparent panel 166 that configuration is for example formed by glass or allyl resin above upper electrode 18, at the collector electrode 168 that the back side of transparent panel 166 (in the face of the face of upper electrode 18) configuration for example is made of transparency electrode, coating fluorophor 170 on this collector electrode 168.In addition, through resistance bias supply 172 (collector voltage Vc) is connected on the collector electrode 168.In addition, electronic emission element 12B will be configured in the vacuum space certainly.The vacuum degree of atmosphere is 10 ²～10 ^-6In the scope of handkerchief for well, preferably 10 ^-3～10 ^-5Handkerchief.

Select the reason of such scope to be, (1) is owing to gas molecule in the space is many under low vacuum, so generate plasma easily, if plasma generation gets too much, its cation clashes into upper electrode 18 in large quantities, may damage upper electrode 18, perhaps (2) meeting and gas molecule collision before emitting electrons arrives collector electrode 168, the electronics that is fully quickened by collector voltage Vc makes exciting of fluorophor 170 carry out insufficiently.

On the other hand, be because there is following problem: under high vacuum, though from the concentrated easy emitting electrons of point of electric field, it is big that the support of structure and vacuum seal portion just become, and is unfavorable for miniaturization.

In the example of Figure 63, the back side at transparent panel 166 forms collector electrode 168, form fluorophor 170 on the surface of this collector electrode 168 (in the face of the face of upper electrode 18), but, in addition, shown in Figure 64, also can be formed on fluorophor 170 back side of transparent panel 166, form collector electrode 168 again and cover this fluorophor 170.

This is the formation in uses such as CRT, and collector electrode 168 is as metal back.After the penetration of electrons collector electrode 168 that emitter 22 emits, enter fluorophor 170, excite this fluorophor 170.Therefore, the thickness of collector electrode 168 is preferably made the thickness that electronics can penetrate, preferably smaller or equal to 100nm.The kinetic energy of electronics is big more, and the thickness of collector electrode 168 can be done thickly more.

According to such formation, can obtain following effect.

(a) fluorophor 170 does not have under the situation of conductivity, can prevent fluorophor 170 charged (bearing), can keep the accelerating field of electronics.

(b) collector electrode 168 reflected fluorescent light bodies 170 is luminous, can launch the luminous of fluorophor 170 to transparent panel 166 sides (light-emitting area side) effectively.

(c) can prevent that electronics from exceedingly clashing into fluorophor 170, can prevent the deterioration of fluorophor 170 or produce from the gas of fluorophor 170.

Four experimental examples (first～the 4th experimental example) of the employed electronic emission element 12B of light source 10B of this second execution mode are shown below.

First experimental example is an experimental example of observing the electronics emission state of electronic emission element 12B.That is, shown in Figure 65 A, electronic emission element 12B applied have-70V voltage write pulse Pw, make the electronics savings in electronic emission element 12B, then, apply bright lamp pulse Ph with 280V voltage, allow electronics emit.Detect the luminous emission state of measuring electronics of fluorophor 170 with photo detector (photodiode).Detection waveform is shown in Figure 65 B.In addition, establishing the duty ratio that writes pulse Pw and bright lamp pulse Ph is 50%.

By this first experimental example as can be known, from bright lamp pulse Ph preceding on the way beginning luminous, finish luminous in the initial stage of this bright lamp pulse Ph.Therefore, even establishing shortlyer during the bright lamp pulse Ph, can not influence luminous yet.The shortening that this is related to during high-tension the applying helps reducing consumed power.

Second experimental example is to observe the experimental example how electron emission amount of electronic emission element 12B changes with the amplitude that writes pulse Pw shown in Figure 66.The same with first experimental example, also be the luminous variation of measuring the emission measure of electronics that detects fluorophor 170 with photo detector (photodiode), experimental result is shown in Figure 67.

In Figure 67, the amplitude that the amplitude that solid line A represents to establish bright lamp pulse Ph is 200V, write pulse Pw changes to-characteristic under the situation of 80V from-10V; The amplitude that the amplitude that solid line B represents to establish bright lamp pulse Ph is 350V, write pulse Pw changes to-characteristic under the situation of 80V from-10V.

Shown in Figure 67, as can be known make write pulse Pw and change to from-20V-situation of 40V under, luminosity almost straight line changes.Particularly, if the amplitude of brighter lamp pulse Ph is the situation of 350V and the situation of 200V, the wide dynamic range that under the situation of 350V the luminosity that writes pulse Pw is changed helps improving luminosity as can be known.In addition, the light source 10B of second execution mode is being used under the situation of display, can improving the contrast (contrast) of this display.Can think that this tendency for the amplitude setting of bright lamp pulse Ph, helps improving the amplitude of bright lamp pulse Ph in the scope before luminosity reaches capacity, but preferably according to setting optimum value with the relation withstand voltage or consumed power of signal transmission system.

The 3rd experimental example is the experimental example how electron emission amount of observing electronic emission element 12B changes with the amplitude of the bright lamp pulse Ph shown in Figure 66.The same with first experimental example, also be the luminous variation of measuring the emission measure of electronics that detects fluorophor 170 with photo detector (photodiode), experimental result is shown in Figure 68.

In Figure 68, solid line C represents to establish the amplitude that writes pulse Pw and changes to characteristic under the situation of 400V for the-amplitude of 40V, bright lamp pulse Ph from 50V; Solid line D represents to establish the amplitude that writes pulse Pw and changes to characteristic under the situation of 400V for the-amplitude of 70V, bright lamp pulse Ph from 50V.

Shown in Figure 68, as can be known bright lamp pulse Ph is changed under the situation of 300V from 100V, luminosity almost straight line changes.Particularly, if the amplitude that relatively writes pulse Pw is the situation of-40V situation with-70V, the wide dynamic range that under the situation of-70V the luminosity of bright lamp pulse Ph is changed as can be known helps improving luminosity and helps improving contrast under the situation that is used in display.Can think that this tendency is for the amplitude setting that writes pulse Pw, help improving the amplitude (being absolute value at this moment) that writes pulse Pw in the scope before luminosity reaches capacity, but in this case preferably also according to setting optimum value with the relation withstand voltage or consumed power of signal transmission system.

The 4th experimental example is the experimental example how electron emission amount of observing electronic emission element 12B changes with the level of the collector voltage Vc shown in Figure 63 or Figure 64.The same with first experimental example, also be the luminous variation of measuring the emission measure of electronics that detects fluorophor 170 with photo detector (photodiode), experimental result is shown in Figure 69.

In Figure 69, the level that solid line E represents to establish collector voltage Vc is that the amplitude of 3kV, bright lamp pulse Ph changes to the characteristic under the situation of 500V from 80V; The level that solid line F represents to establish collector voltage Vc is that the amplitude of 7kV, bright lamp pulse Ph changes to the characteristic under the situation of 500V from 80V.

Shown in Figure 69, as can be known collector voltage Vc be under the situation of 7kV than collector voltage Vc be the situation of 3kV to the wide dynamic range that the luminosity of bright lamp pulse Ph changes, help improving luminosity and help improving contrast under the situation that is used in display.Can think that this tendency helps improving the level of collector voltage Vc, but in this case preferably also according to setting optimum value with the relation withstand voltage or consumed power of signal transmission system.

A kind of driving method of the light source 10B of the second above-mentioned execution mode is described with reference to Figure 70 and Figure 71 here.What Figure 70 represented is the action of the pixel of representational 1 row, 1 row, 2 row, 1 row and capable 1 row of n.In addition, employed here electronic emission element 12B has the coercive voltage v1 at the some p2 place of Figure 55 and for example for the coercive voltage v2 at-20V, some p5 place for example for the voltage v3 at+70V, some p3 place for example for-50V, the voltage v4 that puts the p4 place for example is+characteristic of 50V.

In addition, shown in Figure 70, with select whole row during during as a frame, include during the electric charge savings Th between Td and light emission period in this frame, comprise Ts during n the selection during the electric charge savings among the Td.During each is selected Ts for the selection of corresponding respectively row during Ts, so, be Tn during the non-selection for not corresponding n-1 row.

And, this driving method is the whole electronic emission element 12B of Td interscan during the electric charge savings, on a plurality of electronic emission element 12B, apply voltage respectively, put aside electric charge (electronics) respectively at a plurality of electronic emission element 12B thus according to the amount of the intensity level of the light-emitting component of correspondence corresponding to the light-emitting component of ON object according to the intensity level of the light-emitting component of correspondence corresponding to the pixel of ON object (luminous object); Th between next light emission period, certain voltage is applied on whole electronic emission element 12B, launch electronics respectively from a plurality of electronic emission element 12B, thereby make the light-emitting component of ON object luminous according to the amount of the intensity level of the light-emitting component of correspondence corresponding to the light-emitting component of ON object.

If specify, shown in Figure 71, at first, Ts during the selection of first row the capable selection wire 144 that the selection signal Ss of for example 50V supplies with first row, supplies with the capable selection wire 144 that other are gone to the non-select signal Sn of for example 0V.Be fed into the light-emitting component that should be ON (luminous) in the first row light-emitting component holding wire 146 data-signal Sd voltage range for more than or equal to 0V smaller or equal to 30V, and be respectively voltage according to the intensity level of the light-emitting component of correspondence.If intensity level is the highest, be 0V just.Modulation according to the intensity level of this data-signal Sd is undertaken by the pulse-width modulation circuit 164 shown in the modulation circuit shown in Figure 58 160 or Figure 60.

Like this, between the upper electrode 18 of electronic emission element 12B of each light-emitting component that should be ON that corresponds respectively to first row and lower electrode 20, apply more than or equal to-50V according to intensity level respectively and smaller or equal to the voltage of-20V.As a result, in each above-mentioned electronic emission element 12B savings corresponding to the electronics of the voltage that is applied.For example, electronic emission element 12B corresponding to the light-emitting component of first row first row for example is a maximum brightness level, just become the state of some p3 of the characteristic of Figure 55 thus, the electronics of maximum is put aside in emitter 22 in the part of exposing from the breakthrough part 102 of upper electrode 18.

In addition, be fed into voltage corresponding to the data-signal Sd of the electronic emission element 12B of the light-emitting component of expression OFF (delustring) for example for 50V, therefore, apply 0V at electronic emission element 12B corresponding to the light-emitting component of OFF object, the state of point p1 that this just becomes the characteristic of Figure 55 does not carry out the savings of electronics.

After the supply end to the first data-signal Sd that goes, Ts during the selection of second row the capable selection wire 144 that the selection signal Ss of 50V supplies with second row, supplies with the capable selection wire 144 that other are gone to the non-select signal Sn of 0V.In this case, also apply more than or equal to-50V according to intensity level respectively between corresponding to the upper electrode 18 of the electronic emission element 12B of the light-emitting component that should be ON (luminous) and lower electrode 20 and smaller or equal to the voltage of-20V.At this moment, corresponding to applying more than or equal to 0V smaller or equal to the voltage of 50V between the upper electrode 18 of electronic emission element 12B of for example light-emitting component of first row that is in nonselection mode and the lower electrode 20, but because this voltage is the voltage of level of point 4 that does not reach the characteristic of Figure 55, so not from corresponding to the electronic emission element 12B emitting electrons that should be the light-emitting component of ON (luminous) first row.In a word, the light-emitting component of first of the nonselection mode row is not supplied with the influence of data-signal Sd of pixel of second row of selection mode.

Equally, Ts during the capable selection of n supplies with the capable capable selection wire 144 of n to the selection signal Ss of 50V, the non-select signal Sn of 0V is supplied with the capable selection wire 144 of other row.In this case, also apply more than or equal to-50V according to intensity level respectively between corresponding to the upper electrode 18 of the electronic emission element 12B of the light-emitting component that should be ON (luminous) and lower electrode 20 and smaller or equal to the voltage of-20V.At this moment, corresponding to applying between the upper electrode 18 of the electronic emission element 12B of each light-emitting component of first row～the (n-1) row that is in nonselection mode and the lower electrode 20 more than or equal to 0V, still from light-emitting component, not should be the electronic emission element 12B emitting electrons of the light-emitting component of ON (luminous) corresponding to these nonselection modes smaller or equal to the voltage of 50V.

The stage of Ts enters Th between light emission period during having passed through the capable selection of n.Th between this light emission period, by signal supply circuit 150 reference voltage (for example 0V) is applied on the upper electrode 18 of whole electronic emission element 12B, general-350V voltage (pulse power 156-the capable supply voltage 50V that selects circuit 148 of 400V+) be applied on the lower electrode 20 of whole electronic emission element 12B.Like this, just between the upper electrode 18 of whole electronic emission element 12B and lower electrode 20, added high voltage (+350V).All electronic emission element 12B become the state of some p6 of the characteristic of Figure 55 respectively, shown in Figure 57 C, have put aside the part of described electronics in the emitter 22 and have launched electronics by breakthrough part 102.Certainly, also nearby launch electronics from the peripheral part of upper electrode 18.

In a word, from the electronic emission element 12B emitting electrons corresponding to the light-emitting component that should be ON (luminous), the electronics that is emitted is introduced in the collector electrode 168 corresponding to these electronic emission elements 12B, excites corresponding fluorophor 170, makes it luminous.This luminous outwards radiation of surface by transparent panel 166.

Same later on, with the frame is unit, Td during the electric charge savings, at electronic emission element 12B inner product electric power storage corresponding to the light-emitting component that should be ON (luminous), Th between light emission period, the electronics that emission is put aside and produce fluorescence radiation, outwards radiation is this luminous the surface by transparent panel 166 thus.

Like this, in the light source 10B of this second execution mode, as mentioned above, Td during the electric charge savings in a frame, scan whole electronic emission element 12B, on a plurality of electronic emission element 12B, apply voltage respectively, in a plurality of electronic emission element 12B, put aside electric charge thus respectively according to the amount of the intensity level of the light-emitting component of correspondence corresponding to the light-emitting component of ON object according to the intensity level of the light-emitting component of correspondence corresponding to the light-emitting component of ON object; Th between next light emission period, certain voltage is applied on whole electronic emission element 12B, from corresponding to a plurality of electronic emission element 12B emissions of the light-emitting component of ON object electronics, can make the light-emitting component of ON object luminous respectively according to the amount of the intensity level of the light-emitting component of correspondence.

In addition, among the electronic emission element 12B that uses in the light source 10B of this second execution mode, the voltage V3 that for example is in electronics savings saturation condition with the relation of the voltage V4 of beginning electronics emission is:

1≤|V4|/|V3|≤1.5

Usually, for example be arranged in electronic emission element 12B rectangular, synchronously select electronic emission element 12B with 1 behavior unit with horizontal scan period, when the electronic emission element 12B that is in selection mode is supplied with data-signal Sd according to the intensity level of light-emitting component respectively, the light-emitting component of nonselection mode is also supplied with data-signal Sd.

The electronic emission element 12B of nonselection mode is subjected to the influence of data-signal Sd and when for example launching electronics, can causes the brightness disproportionation of light source 10B etc.

But, because this electronic emission element 12B has above-mentioned characteristic, so the voltage level of the data-signal Sd of the electronic emission element 12B that supplies with selection mode is taken as free voltage from reference voltage to voltage V3, and supply with for example polarity reversing signal of data-signal Sd for the electronic emission element 12B setting of nonselection mode, even so simple voltage relationship, the light-emitting component of nonselection mode are not subjected to the influence to the data-signal Sd of the light-emitting component of selection mode yet.Promptly, the electronics amount of savings of each light-emitting component of putting aside in the Ts during the selection of each light-emitting component (carried charge of the emitter 22 among each electronic emission element 12B) is maintained to till Th emitting electrons between next light emission period, the result, just can realize the memory effect in each light-emitting component, can realize high brightness, high-contrast.

On the other hand, in the light source 10B of this second execution mode, Td during the electric charge savings, all putting aside necessary electric charge in the electronic emission element 12B, Th between light emission period thereafter, whole electronic emission element 12B are applied electronics launch necessary voltage,, thereby make the light-emitting component of ON object luminous from a plurality of electronic emission element 12B emitting electrons corresponding to the light-emitting component of ON object.

Usually, be made of electronic emission element 12B under the situation of light-emitting component, light-emitting component is luminous must to be applied to high voltage on the electronic emission element 12B in order to make.Therefore, savings electric charge when light-emitting component is scanned, thus make under its further luminous situation, need during making luminous whole of light-emitting component, (a for example frame) apply high voltage, there is the big problem of consumed power.In addition, the circuit of selecting each electronic emission element 12B and supplying with data-signal Sd also must be made corresponding to high-tension circuit.

But, in this embodiment, after electric charge savings is in whole electronic emission element 12B, whole electronic emission element 12B are applied voltage, make corresponding to the light-emitting component of the electronic emission element 12B of ON object luminous.

Therefore, whole electronic emission element 12B are applied the voltage (emission voltage) that is used for electronics emission during Th lack than a frame certainly, and, by first experimental example shown in Figure 65 A and Figure 65 B as can be known, owing to can will establish to such an extent that lack a bit during the emission voltage application, compare with luminous situation so carry out the savings of electric charge during with the scanning light-emitting component, can reduce consumed power significantly.

In addition, because separate, so can realize being used for each electronic emission element 12B is applied low voltage drive according to the circuit of the voltage of intensity level respectively at Td during the electronic emission element 12B inner product electric power storage lotus and Th during corresponding to the electronic emission element 12B emitting electrons of the light-emitting component of ON object.

In addition, must be to the selection signal Ss/ non-select signal Sn of Td during every row or every row driving data signal Sd and the electric charge savings, but seen in above-mentioned execution mode, arrive, because driving voltage can be tens of volts, can be used in many output drivers of the cheapness of uses such as fluorescent display tube.On the other hand, Th between light emission period is though fully the voltage of emitting electrons may be greater than described driving voltage, because of just passable as long as drive the light-emitting component of whole ON objects in the lump, so do not need the circuit block of many outputs.For example, as long as the only drive circuit of an output that is made of withstand voltage high discrete component is arranged, so the benefit that cost is very low and circuit scale is little is arranged.Approach a bit by the thickness of emitter 22 is made, can realize the lower voltage of above-mentioned driving voltage and discharge voltage.Therefore, for example can drop to several volts to driving voltage by setting thickness.

And then, according to this driving method, owing to separate with the phase I of line scanning, and whole light-emitting components do not rely on the electronics emission of the second stage of line scanning simultaneously, so do not rely on exploring degree, picture size, guarantee fluorescent lifetime easily, can improve brightness.

Below, the various variation of the electronic emission element 12B that uses among the light source 10B of second execution mode are described with reference to Figure 72～Figure 77.

At first, shown in Figure 72, the structure that the electronic emission element 12Ba of first variation has and above-mentioned electronic emission element 12B is identical substantially, still, following some have feature: the constituent material of upper electrode 18 is identical with the constituent material of lower electrode 20; The thickness t of upper electrode 18 is greater than 10 μ m; By etching (Wet-type etching, dry-etching) or peel off, the artificial breakthrough part 102 that forms such as laser.The shape of breakthrough part 102 is the same with above-mentioned electronic emission element 12B, can adopt the shape in hole 114, the shape of breach 128, the shape of slit 132.

And then the following 108a of the perimembranous 108 of the breakthrough part 102 of upper electrode 18 tilts at leisure upward towards the center of breakthrough part 102.This shape can form simply with for example stripping means.

Used among the light source 10B of electronic emission element 12Ba of this first variation, also the same with the situation of having used above-mentioned electronic emission element 12B, can easily produce high electric field concentrates, and, can increase electronics emission place, height output, the high efficiency of electronics emission can be realized, low voltage drive (low consumpting power) can also be realized.

In addition, the electronic emission element 12Bb of second variation shown in Figure 73 is such, also can the part corresponding to breakthrough part 102 on emitter 22 have floating electrode 174.

In addition, the electronic emission element 12Bc of the 3rd variation shown in Figure 74 is such, also can form section configuration and be the electrode of T font substantially as upper electrode 18.

In addition, the electronic emission element 12Bd of the 4th variation shown in Figure 75 is such, also can make the shape of perimembranous 108 come-up of the breakthrough part 102 of the shape of upper electrode 18, particularly upper electrode 18.As long as in the membrane material that constitutes upper electrode 18, comprise the material that gasifies in the sintering circuit.Like this, in sintering circuit described material is gasified, the result makes: the shape of perimembranous 108 come-ups of breakthrough part 102 in a plurality of breakthrough parts 102 of formation on upper electrode 18.

The electronic emission element 12Be of the 5th variation is described below with reference to Figure 76.

Shown in Figure 76, the electronic emission element 12Be of the 5th variation is identical substantially with the structure of above-mentioned electronic emission element 12B, and difference is to have a substrate 176 that for example is made of pottery; Lower electrode 20 is formed on the substrate 176, and emitter 22 is on substrate 176 and cover lower electrode 20, and upper electrode 18 is formed on the emitter 22 again.

In the inside of substrate 176, be provided with the cavity 178 that is used for forming thinner wall section described later corresponding to the position of the part that forms each emitter 22.Cavity 178 is by the through hole 180 and the external communications of the minor diameter on other end faces that are arranged on substrate 176.

Be formed with the part wall thin (following record is a thinner wall section 182) of cavity 178 in the described substrate 176, the remainder wall thickness plays the fixed part 184 of the described thinner wall section 182 of support.

In a word, substrate 176 is as undermost substrate layer 176A, as the wall 176B in intermediate layer, as the laminated body of the thin plate layer 176C of the superiors, can think to have formed in the place corresponding to emitter 22 among the wall 176B integrative-structure of cavity 178.Substrate layer 176A strengthens also being used as the substrate of wiring usefulness with the substrate except that being used as.In addition, both substrate layer 176A, wall 176B, thin plate layer 176C one sintering can be formed substrate 176, and also can be bonded together these layers 176A～176C and form substrate 176.

Thinner wall section 182 is the high-fire resistance material preferably.This is because do not use the bad material of thermal endurance such as organic adhesive, and emitter 22 is made under the situation of the structure of using fixed part 184 directly to support thinner wall section 182, at least thinner wall section 182 undergoes no deterioration when forming emitter 22, so thinner wall section 182 high-fire resistance material preferably.

In addition, for the wiring of leading to upper electrode 18 that is formed on the substrate 176 separates with the electricity of the wiring of leading to lower electrode 20, thinner wall section 182 is electrical insulating material preferably.

Therefore, as the material of thinner wall section 182, can be the metal of high-fire resistance or covered the hollow material of this metal surface, but only material be a pottery with ceramic materials such as glass.

As the pottery that constitutes thinner wall section 182, for example can use the zirconia, aluminium oxide, magnesium oxide, titanium oxide, spinelle, mullite, aluminium nitride, silicon nitride, glass of stabilisation, their mixture etc.Wherein, from the viewpoint of intensity and rigidity, the zirconia of aluminium oxide and stabilisation preferably.Higher from mechanical strength, toughness is higher, the less viewpoint of chemical reaction of upper electrode 18 and lower electrode 20, the zirconia of stabilisation is the most suitable.In addition, the zirconia of so-called stabilisation comprises stabilized zirconia and partially stabilizedization zirconia.Because the zirconia of stabilisation is taked the crystalline texture of cube crystalline substance, therefore do not produce phase transfer.

On the other hand, zirconia is 1000 ℃ of up and down phase transfers between monoclinic crystal and regular crystal, may crack during such phase transfer.The zirconia of having stablized contains 1～30% mole calcium oxide, magnesium oxide, yittrium oxide, scandium oxide, ytterbium oxide, cerium oxide, the stabilizers such as oxide of rare earth metal.In addition, in order to improve the mechanical strength of substrate 176, stabilizer preferably contains yittrium oxide.In this case, the yittrium oxide that contains 1.5～6% moles is comparatively suitable, and the yittrium oxide that contains 2～4% moles is more suitable, preferably also contains 0.1～5% mole aluminium oxide.

In addition, though crystalline phase can be made a cube crystalline substance+monoclinic mixing phase, regular crystal+monoclinic mixing phase, cube crystalline substance+regular crystal+monoclinic mixing equates, but from the viewpoint of intensity, toughness and durability, wherein suitable is the mixing phase of primary crystallization being made mutually regular crystal or regular crystal+cube crystalline substance.

Be made of pottery under the situation of substrate 176, many crystal grain constitutes substrate 176, but in order to improve the mechanical strength of substrate 176, it is comparatively suitable that the mean particle diameter of crystal grain is made 0.05～2 μ m, is preferably made 0.1～1 μ m.

On the other hand, fixed part 184 preferably is made of pottery, both can be the ceramic material identical with thinner wall section 182, also can be different ceramic materials.As the pottery that constitutes fixed part 184, the same with the material of thinner wall section 182, for example can use the zirconia, aluminium oxide, magnesium oxide, titanium oxide, spinelle, mullite, aluminium nitride, silicon nitride, glass of stabilisation, their mixture etc.

Particularly the substrate 176 that uses in this electronic emission element 12Be preferably adopts with zirconia as the material of main component, be material of main component etc. with aluminium oxide as the material of main component or with their mixture.Wherein, preferably be the material of main component with the zirconia.

In addition, also add clay etc. sometimes, but must regulate the assistant composition, so that the unlikely easy vitrified compositions such as excessive silica, boron oxide that contain as sintering adjuvant.Though this is because these easy vitrified materials help making substrate 176 and emitter 22 bonding, be difficult to promote the reaction of substrate 176 and emitter 22, be difficult to keep the composition of the emitter 22 of regulation, the result makes element characteristic decline.

That is, preferably the weight ratio of the silica in the substrate 176 etc. is limited in 3% or below it, is limited in 1% or it is following better.Here, so-called main component is that weight ratio is 50% or its above composition.

In addition, the thickness of the thickness of described thinner wall section 182 and emitter 22 is preferably with the thickness of the order of magnitude.This be because if the thickness of thinner wall section 182 excessively than the thickness of emitter 22 thick (difference that or its are above), thinner wall section 182 can hinder the sintering of emitters 22 to shrink, so the stress on the interface of emitter 22 and substrate 176 becomes big, peels off easily.On the contrary, if thickness approximately is same order, then substrate 176 (thinner wall section 182) is followed the sintering contraction of emitter 22 easily, so be suitable for integrated.Specifically, the suitable thickness of thinner wall section 1 82 is 1～100 μ m, and 3～50 μ m are better, and 5～20 μ m are best.On the other hand, the suitable thickness of emitter 22 is 5～100 μ m, and 5～50 μ m are better, and 5～30 μ m are best.

Method as form emitter 22 on substrate 176 can adopt various film forming methods such as various thick film forming methods such as wire mark method, infusion process, coating process, electrophoresis, atomizing sedimentation or ion beam method, sputtering method, vacuum vapour deposition, ion plating, chemical vapor-phase growing method (CVD), plating.Good especially method is as emitter 22, forms the material of piezoelectric/electrostrictive material powdered, floods low-melting glass or sol particles again.Just can carry out the film formation down of 700 ℃ or 600 ℃ or its following low temperature in this way.

In addition, sintering processes as electronic emission element 12Be, both can on substrate 176, stacked above one another constitute the material of lower electrode 20, the material of formation emitter 22 and the material of formation upper electrode 18, then as the integrative-structure sintering, also can when forming lower electrode 20, emitter 22, upper electrode 18 respectively, heat-treat (sintering processes) and be made of one structure with substrate 176.In addition, according to the formation method of upper electrode 18, also needn't be used for incorporate heat treatment (sintering processes) sometimes with lower electrode 20.

As being used for substrate 176, emitter 22, upper electrode 18 and lower electrode 20 are made of one the temperature of the sintering processes of structure, suitable scope is 500 ℃～1400 ℃, preferably 1000 ℃～1400 ℃ scope.Further, when membranaceous emitter 22 is heat-treated,, when being preferably in evaporation source with emitter 22 and carrying out atmosphere control, carry out sintering processes in order to be unlikely to make the composition instability of emitter 22 when the high temperature.

In addition, also can adopt the suitable material of emitter 22 usefulness is covered and to make the surface of emitter 22 not be directly exposed to the method for carrying out sintering in the sintering atmosphere, in this case, the same material of the most handy and substrate 176 is as cladding material.

In the electronic emission element 12Be of the 5th variation, emitter 22 shrinks during sintering, but the distortion of the stress of generation by cavity 178 etc. is released during this contraction, can make emitter 22 abundant densifications thus.In the time of the raising of the densification degree by emitter 22, withstand voltage rising, carry out the polarization reversals in the emitter 22 effectively and change polarization, will rise as the characteristic of electronic emission element 12Be.

In the 5th above-mentioned variation, the substrate that uses 3-tier architecture is as substrate 176, still, also can use the substrate 176a of 2 layers of structure having omitted undermost substrate layer 176A as the electronic emission element 12Bf of the 6th variation of Figure 77 in addition.

The same with the light source 10Ac of the 3rd variation shown in Figure 16, the light source 10B of this second execution mode also can be divided into two groups (first and second groups G1 and G2) to illuminating part 14B, be included in electronic emission element 12B in first group of G1 when luminous, the Power Recovery that is included in the interior electronic emission element 12B of first group of G1 to being included among second group of electronic emission element 12B in the G2; Be included in electronic emission element 12B in second group of G2 when luminous, the Power Recovery that is included in the interior electronic emission element 12B of second group of G2 to being included among first group of electronic emission element 12B in the G1.

In addition, in the light source 10B of second execution mode, the light source 10Ae of the 5th variation that also can image pattern 29 is such, has two or its above Z1～Z6 of area source portion.In the example of Figure 29, represented to have the situation of six Z1～Z6 of area source portion.Each Z1～Z6 of area source portion arranges a plurality of electronic emission element 12B two-dimensionally and forms, and is connecting drive circuit 16B independently respectively.

Like this, just can be with the Z1～Z6 of the area source portion luminous/delustring that is that unit controls, and can carry out incremental dimming (digital type light-adjusting).Particularly be provided with modulation circuit 60 (with reference to Figure 18) among the drive circuit 16B on being connected each Z1～Z6 of area source portion respectively independently, just can distinguish the luminescence distribution of controlling each Z1～Z6 of area source portion independently thus.That is, except that digital type light-adjusting, analog light modulation can also be realized, careful light modulation can be carried out.

In addition, in the light source 10B of second execution mode, the light source 10Af of the 6th variation that also can image pattern 30 is such, the first and the 6th Z1 of area source portion and Z6 is done the rectangle of putting sidewards of the growth length of side respectively; The second and the 5th area source portion is done the rectangle that stands on end of the growth limit lengthwise shorter respectively than the long limit of the first and the 6th Z1 of area source portion and Z6; Third and fourth Z3 of area source portion and Z4 are done the growth limit rectangle of sidewards putting shorter than the long limit of the first and the 6th Z1 of area source portion and Z6 respectively.

In addition, in the light source 10B of second execution mode, the light source 10Ag of the 7th variation shown in also can image pattern 31 is such, be divided into two groups (first group and second group of G1 and G2) respectively being included in a plurality of electronic emission element 12B in each Z1～Z6 of area source portion, in each Z1～Z6 of area source portion, be included in electronic emission element 12B in first group of G1 when luminous, the Power Recovery that is included in the interior electronic emission element 12B of this first group of G1 to being included among second group of electronic emission element 12B in the G2; Be included in electronic emission element 12B in second group of G2 when luminous, the Power Recovery that is included in the interior electronic emission element 12B of this second group of G2 to being included among first group of electronic emission element 12B in the G1.

In addition, in the light source 10B of second execution mode, the light source 10Ah of the 8th variation shown in also can image pattern 32 is such, six Z1～Z6 of area source portion are divided into two groups (first group and second group of G1 and G2), when each electronic emission element 12B of the Z1～Z3 of area source portion of relevant first group of G1 is luminous, the Power Recovery of these electronic emission elements 12B in the electronic emission element 12B of the Z4～Z6 of area source portion of relevant second group of G2; When each electronic emission element 12B of the Z4～Z6 of area source portion of relevant second group of G2 is luminous, the Power Recovery of these electronic emission elements 12B in the electronic emission element 12B of the Z1～Z3 of area source portion of relevant first group of G1.

In addition, in the light source 10B of second execution mode, also can adopt the structure shown in the light source 10Ai～10Am of the 9th～the 13 variation of Figure 33～shown in Figure 37.

The light source 10B of the light source 10A of first execution mode (comprising various variation) and second execution mode can obtain following effect at (comprising various variation).

(1) from realizing high brightnessization, the consideration of low consumpting power aspect, is most appropriate to the light source that needs the projector of 2000 lumens to use as brightness specifications.

(2) realize high brightness two-dimensional array light source easily, actuating range is wide, even luminous efficiency can not change yet under outdoor environment, so, be expected to be used for to substitute LED.For example, optimum is as the substitute products of two-dimensional array led modules such as semaphore.In addition, at 25 ℃ or more than it, the allowable current of LED descends, and presents low-light level.

(3) two-dimensional arrangements electronic emission element and the area source that constitutes can be that unit controls bright lamp/light-off with the element is so be suitable for making the purposes of the bright lamp of a part/light-off of light-emitting zone.In addition, but since moment bright lamp, so do not need time of heating up.In addition, under the situation of the backlight of using as LCD, also can improve quality (improving the fuzzy of animation) based on the animated image of the bright lamp of high speed.

In addition, light source of the present invention is not limited to above-mentioned execution mode, certainly, does not deviate from aim of the present invention and can obtain various formations.

Claims

1. one kind produces the light source of light by the electronic impact material, it is characterized in that,

The generation source of described electronics is electronic emission element (12A);

Described electronic emission element (12A),

Have the emitter (22) that constitutes by dielectric, be formed on first electrode and second electrode on the described emitter (22),

By between described first electrode (18) and second electrode (20), applying driving voltage (Va), make at least a portion generation polarization reversal of described emitter (20) or change polarization, carry out the electronics emission thus.

2. light source as claimed in claim 1 is characterized in that,

By between described first electrode (18) and described second electrode (20), applying described driving voltage (Va), make at least a portion generation polarization reversal of described emitter (22), by this polarization reversal, the side of the positive electrode of dipole is configured in the periphery of described first electrode (18), primary electron is attracted out from described first electrode (18);

The primary electron that attracts to come out from described first electrode (18) clashes into described emitter (22), launches secondary electron from this emitter (22).

3. light source as claimed in claim 2 is characterized in that,

Three remittance nodes with described first electrode (18), described emitter (22) and vacuum atmosphere;

Three remittance nodes part nearby from described first electrode (18) attracts primary electron;

The primary electron that is attracted out clashes into described emitter (22), launches secondary electron from this emitter (22).

4. one kind produces the light source of light by electronic impact, it is characterized in that,

The generation source of described electronics is electronic emission element (12B);

Described electronic emission element (12B),

Have the emitter (22) that constitutes by dielectric, first electrode (18) and second electrode (20) that has applied the driving voltage (Va) that is used for the electronics emission,

Described first electrode (18) is formed on first of described emitter (22),

Described second electrode (20) is formed on second of described emitter (22),

At least described first electrode (18) has a plurality of breakthrough parts (102) that described emitter (22) exposes,

The face (102a) in the face of described emitter (22) in the perimembranous (108) of breakthrough part (102) described in described first electrode (18) leaves described emitter (22).

5. light source as claimed in claim 4 is characterized in that,

Described electronic emission element (10B),

In the phase I, carry out the electronics emission from described first electrode (18) to described emitter (22), make described emitter (22) charged;

In second stage, described emitter (22) carries out the electronics emission.

6. as claim 4 or 5 described light sources, it is characterized in that,

In described second stage, from the electronics of described emitter (22) emission corresponding to the carried charge of described emitter (22) during described phase I.

7. as any described light source of claim 4～6, it is characterized in that,

The carried charge of described emitter (22) in the described phase I is maintained to till the electronics emission of carrying out described second stage.

8. as any described light source of claim 1～7, it is characterized in that,

Described emitter (22) is made of piezoelectric, antiferroelectric dielectric material or electrostriction material.

9. as any described light source of claim 1～8, it is characterized in that,

Have and between described first electrode (18) and described second electrode (20), apply the unit (16A, 16B) that is used for making at least a portion generation polarization reversal of described emitter (22) or changes the alternating-current pulse of polarization;

From described emitter (22) emitting electrons discontinuously.

10. light source as claimed in claim 9 is characterized in that,

Before launching the luminous delustring that causes, electronics once carries out electronics emission next time, thus luminous continuously.

11. any described light source as claim 1～10 is characterized in that,

Have a plurality of described electronic emission elements (12A, 12B), these a plurality of electronic emission elements (12A, 12B) are two-dimensionally arranged.

12. light source as claimed in claim 11 is characterized in that,

Have unit (50), this unit,

(12A, 12B) is divided into two groups described a plurality of electronic emission elements,

When the electronic emission element (12A, 12B) in being included in first group is luminous, is included in second group of interior electronic emission element (12A, 12B) and reclaims the power that is included in the electronic emission element (12A, 12B) in described first group,

Be included in described electronic emission element (12A, 12B) in second group when luminous, the electronic emission element (12A, 12B) in being included in first group reclaims the electronic emission element that is included in described second group

The power of (12A, 12B).

13. any described light source as claim 1～12 is characterized in that,

Have the unit (60) that carries out light modulation, the electron emission amount that described driving voltage (Va) is controlled described electronic emission element (12A, 12B) is modulated according to control signal (Sh) in this unit, carries out light modulation thus.

14. any described light source as claim 1～10 is characterized in that,

Has (the Z1～Z6) of the above area source portion of two or its;

(Z1～Z6) have a plurality of electronic emission elements (12A, 12B), these a plurality of electronic emission elements (12A, 12B) are two-dimensionally arranged in described each area source portion.

15. light source as claimed in claim 14 is characterized in that,

Have a kind of unit, this unit,

Be included in described each area source portion (the described a plurality of electronic emission elements (12A, 12B) in the Z1～Z6) are divided into two groups respectively,

Be included in described electronic emission element (12A, 12B) in second group when luminous, the electronic emission element (12A, 12B) in being included in first group reclaims the power that is included in the electronic emission element (12A, 12B) in described second group.

16. light source as claimed in claim 14 is characterized in that,

Have a kind of unit, this unit,

The above area source portion of described two or its (Z1～Z6) be divided into two groups,

17. any described light source as claim 14～16 is characterized in that,

Have and carry out described each area source portion (unit of the light modulation of Z1～Z6), this unit is for (the Z1～Z6) of described each area source portion, control signal (Sh) according to correspondence is modulated the driving voltage (Va) that is applied to respectively on the electronic emission element (12A, 12B), control the electron emission amount of described electronic emission element (12A, 12B), carry out (the light modulation of Z1～Z6) of each area source portion thus.