WO2002089523A1 - Dispositif de detection des fluctuations de la pression, dispositif d'affichage, dispositif d'enregistrement et de reproduction des sons - Google Patents

Dispositif de detection des fluctuations de la pression, dispositif d'affichage, dispositif d'enregistrement et de reproduction des sons Download PDF

Info

Publication number
WO2002089523A1
WO2002089523A1 PCT/IB2002/001459 IB0201459W WO02089523A1 WO 2002089523 A1 WO2002089523 A1 WO 2002089523A1 IB 0201459 W IB0201459 W IB 0201459W WO 02089523 A1 WO02089523 A1 WO 02089523A1
Authority
WO
WIPO (PCT)
Prior art keywords
optical waveguide
light
substrate
pressure fluctuations
photosensitive element
Prior art date
Application number
PCT/IB2002/001459
Other languages
English (en)
Inventor
Fransiscus G. C. Verweg
Roel H. L. Kusters
Vincent J. J. Van Montfort
Edward J. P. M. Reijnen
Original Assignee
Koninklijke Philips Electronics N.V.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Koninklijke Philips Electronics N.V. filed Critical Koninklijke Philips Electronics N.V.
Publication of WO2002089523A1 publication Critical patent/WO2002089523A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R23/00—Transducers other than those covered by groups H04R9/00 - H04R21/00
    • H04R23/008—Transducers other than those covered by groups H04R9/00 - H04R21/00 using optical signals for detecting or generating sound

Definitions

  • the invention relates to a device for detecting pressure fluctuations, notably for picking up sound signals (microphone), the device comprising a first optical waveguide of an optically transparent material having an entrance portion for light and an exit portion for light opposite a body of a deformable material, a second optical waveguide of an optically transparent material having an entrance portion for light opposite the body of deformable material and an exit portion for light, and a photosensitive element.
  • the invention particularly relates to a microphone for use in a (portable) display device.
  • display devices find an increasingly wider application in, for example, mobile telephones.
  • the invention may also be used in other display devices such as organizers, laptop computers and the like. Due to the increasing miniaturization, the demand for integration of the display screen with the recording function, but also, for example, with the keyboard is increasing.
  • the device for detecting pressure fluctuations is applicable in, for example, dictation apparatus, sound recording apparatus and other recording devices, but also, for example, in a sound reproduction system.
  • USP 5,771,091 describes an optical microphone comprising two different fibers with a membrane spaced apart from an exit portion for light from the first fiber and an entrance portion for light from the second fiber. Light from the first fiber is modulated by motions of the membrane. The modulated light is detected via the second fiber and a photosensitive element.
  • a drawback of this construction is that the fibers and the membrane must be arranged very accurately with respect to each other so that bulk manufacture is substantially impossible. Notably, the fibers must be positioned at a given angle with respect to the membrane so as to obtain a satisfactory operation.
  • the ultimate product is also very sensitive to sudden shocks (dropping) so that use in portable apparatus, notably in mobile telephones, is substantially excluded. It is an object of the invention to solve this problem by means of a method in which integration of said components, or at least parts thereof, is realized as much as possible and, to this end, provides a device for detecting pressure fluctuations, the device comprising a first optical waveguide of an optically transparent material having a first surface, an entrance portion for light along a first part of an edge of the optical waveguide in a plane transverse to the first surface, and an exit portion for light at least at the area of a part of the first surface opposite a body of a deformable material, a second optical waveguide of an optically transparent material having an entrance portion for light opposite the body of deformable material and an exit portion for light along a part of an edge of the second optical waveguide in a plane transverse to the first surface, and a photosensitive element.
  • the invention is based on the recognition that the provision of the exit portion for light from the first optical waveguide and the entrance portion for light from the second optical waveguide in one and the same plane leads to a considerably simpler construction.
  • the optical waveguides can now be implemented in one substrate (for example, molded) so that this simplifies the production.
  • this substrate may form part of a larger assembly in which other functions have been realized.
  • the optical waveguide preferably comprises a substrate or a sub-substrate with sides transverse to the first surface, at least one of which has an entrance face for light, while light from the light source can be coupled in on said side. Due to the possible integration in a larger assembly, said side does not need to be physically present, but "a side transverse to the surface” may alternatively be understood to be a (partial) cross-section transverse to the surface of the substrate.
  • the photosensitive element is then advantageously situated at the location of a further side transverse to the first surface opposite said first side.
  • Said optical waveguide may form part of a larger assembly, for example, a substrate in which also further operating elements for the relevant apparatus (for example, a mobile phone) have been realized.
  • a second optical waveguide may be realized at another location in or on the substrate, which second optical waveguide operates as a waveguide for a light source (backlight or front light) of, for example, a liquid crystal display device.
  • the microphone may of course also be integrated in other apparatus, for example recording devices for recording pressure fluctuations or sound (dictation apparatus) or sound reproduction systems (rings), etc.
  • Fig. 1 is a plan view of a mobile phone comprising a microphone according to the invention.
  • Fig. 2 is a cross-section taken on the line II-II in Fig. 1, while Fig. 3 is a plan view of a part of a substrate in which the microphone has been realized, and
  • Fig. 4 is a cross-section taken on the line IV-IV in Fig. 3.
  • the drawings are diagrammatic and not drawn to scale. Corresponding components are generally denoted by the same reference numerals.
  • Fig. 1 shows a device 1 according to the invention, in this case a mobile phone comprising the customary keys 2, a display 3 and a microphone 4 in a housing 5.
  • the display is a liquid crystal display device with a layer of liquid crystal material (not shown) between two substrates 6, 7.
  • the display 3 may be of the active (AMLCD) or the passive type.
  • the display 3 is fixed in this example on a transparent support (substrate) 8 (Fig. 2) having recesses 9 at the area of the keys 2. If desired, means for detecting pressure on the keys are present at the area of the recesses 9.
  • the substrate 8 (the support) is, for example, made of a synthetic resin material and has an aperture 10 in which a microphone has been realized.
  • the aperture 10 (see Figs. 3, 4) accommodates a first optical waveguide 11 of an optically transparent material having a first surface 12 and an entrance portion 13 for light along a first part of an edge of the optical waveguide in a plane transverse to the first surface.
  • this plane (and more generally a plane perpendicular to a main surface through which light enters a part of the optical waveguide) is considered to be the entrance portion in the further description.
  • the light is generated by a LED 14 in a further recess 15 in the substrate 8.
  • the light may also be generated at other areas and then be guided towards the entrance portion (plane) 13 by means of mirrors or other optical elements.
  • the optical waveguide further has an exit portion 12' for light at least at the area of a part of the first surface 12. To couple out the light towards the exit portion 12', the optical waveguide has a chamfer or slant 16.
  • the aperture 10 accommodates a second optical waveguide 17 of an optically transparent material having a first surface 18 comprising an entrance portion for light 18'.
  • the optical waveguide 17 has an exit face 19 along a first part of an edge of the optical waveguide in a plane transverse to the first surface. Although light does not immediately need to be detected near this exit face 19, this face (and more generally a face perpendicular to a main surface through which light exits from a part of the optical waveguide) is considered to be the exit portion in the further description.
  • the optical waveguide has a chamfer or slant 20 at the area of the entrance portion.
  • the surfaces 12, 18 are formed as one face.
  • a membrane 21 of a deformable material, for example, of metal is present opposite this face, which membrane is entirely or partly reflective on the side of the optical waveguides 11, 19.
  • the membrane is fixed to supports 22.
  • an aperture 26 accommodates a photodiode 25 or another photosensitive element in the device described.
  • the extent to which the light from the optical waveguide is reflected changes with this deformation.
  • the variation of exiting light is detected by means of a photosensitive element, in this example the photodiode 25.
  • the surfaces 12, 18 of the optical waveguides 11, 17 are formed as one face, a simpler construction is provided which, moreover, can be obtained in a very efficient manner, for example, by means of molding.
  • the problems as regards accuracy when positioning the membrane with respect to the optical waveguides no longer exist either.
  • the variation of exiting light is detected by means of the photosensitive element, in this example the photodiode 25.
  • the light may also be detected at other locations after it has been guided from the face 19 to a suitable location by means of mirrors or other optical elements.
  • the display device is formed with amorphous (or polycrystalline) TFT transistors in a matrix configuration, the matrix can be extended by extra TFT transistors which are specially arranged for detection and, if necessary, optimized for this purpose. This notably applies when the substrate 6 is omitted and the substrate 8 is also used as an LCD substrate.
  • the LED 14 may emit light pulse-wise at a frequency which strongly deviates from the frequency of the (sound) waves to be recorded so that detection is possible through frequency separation.
  • the invention is of course not limited to the examples described hereinbefore.
  • light sources other than LEDs may be used.
  • liquid crystal display device other display devices may be used alternatively such as those that are based on electrophoresis, electroluminescence, P(O)LEDs and, for example, mechanical mirrors.
  • the device for detecting pressure fluctuations is also applicable in completely different fields, for example, in dictation apparatus or other recording apparatus in which such a recording device has, for example, a memory function (for example, as tape recording apparatus, semiconductor memories or a recording function for writable ROMs). More generally, the microphone is applicable in a sound reproduction system comprising at least an amplifier and a loudspeaker.
  • the slanted sides 16, 20 may be omitted, for example, by filling a V-shaped groove (denoted by broken lines 27 in Fig. 4) with a material having a lower refractive index.
  • the grooves are filled, for example, with a suitable monomer and are subsequently polymerized by means of, for example, UV radiation. Variations of the refractive index are also possible to introduce suitable light paths.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)

Abstract

Dans un microphone optique, la membrane (21) est fixée à un corps comprenant un moyen de couplage d'entrée (11) et un moyen de couplage de sortie (17) pour un faisceau lumineux (23, 24), dont l'intensité est influencée par les vibrations de la membrane.
PCT/IB2002/001459 2001-04-26 2002-04-22 Dispositif de detection des fluctuations de la pression, dispositif d'affichage, dispositif d'enregistrement et de reproduction des sons WO2002089523A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP01201521.0 2001-04-26
EP01201521 2001-04-26

Publications (1)

Publication Number Publication Date
WO2002089523A1 true WO2002089523A1 (fr) 2002-11-07

Family

ID=8180208

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2002/001459 WO2002089523A1 (fr) 2001-04-26 2002-04-22 Dispositif de detection des fluctuations de la pression, dispositif d'affichage, dispositif d'enregistrement et de reproduction des sons

Country Status (1)

Country Link
WO (1) WO2002089523A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5857898A (ja) * 1981-09-30 1983-04-06 Matsushita Electric Works Ltd マイクロホン
FR2685961A1 (fr) * 1992-01-06 1993-07-09 Silec Liaisons Elec Capteur optique de vibrations.
EP1139071A1 (fr) * 2000-03-27 2001-10-04 Phone-Or Ltd Capteur optique plat ( microphone ) avec des coins réflectifs

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5857898A (ja) * 1981-09-30 1983-04-06 Matsushita Electric Works Ltd マイクロホン
FR2685961A1 (fr) * 1992-01-06 1993-07-09 Silec Liaisons Elec Capteur optique de vibrations.
EP1139071A1 (fr) * 2000-03-27 2001-10-04 Phone-Or Ltd Capteur optique plat ( microphone ) avec des coins réflectifs

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 007, no. 144 (E - 183) 23 June 1983 (1983-06-23) *

Similar Documents

Publication Publication Date Title
US20200234024A1 (en) Under-screen fingerprint recognition system, liquid crystal display fingerprint recognition apparatus and electronic device
EP2350791B1 (fr) Dispositif tactile utilisant des réseaux optiques
CN108418918B (zh) 电子设备
US7668322B2 (en) Device for detecting pressure fluctuations, display device, recording device and sound reproduction system
US20120212456A1 (en) Apparatus and method for a folded optical element waveguide for use with light based touch screens
KR20200088313A (ko) 감지 도파로의 박막형 커플러 및 리플렉터
US20070041005A1 (en) Fingerprint sensor using microlens
CN111476218A (zh) 一种显示装置
US20070041701A1 (en) Light guide plate and a backlight system
US10712493B2 (en) Display apparatus
US20040136637A1 (en) Sensor,display device and recording device
JP4023979B2 (ja) 光デジタイザ
WO2002089523A1 (fr) Dispositif de detection des fluctuations de la pression, dispositif d'affichage, dispositif d'enregistrement et de reproduction des sons
JP4637884B2 (ja) 光デジタイザ
US11574496B2 (en) Fingerprint recognition device
US6865335B2 (en) Optical microphone for communication and other devices
WO2022056843A1 (fr) Construction optique
US20080074579A1 (en) Backlight module with reflective plate and liquid crystal display employing same
US11238265B1 (en) Electronic device with fingerprint sensing function and fingerprint sensing module
US20070103616A1 (en) Liquid crystal display with frame stopper blocking liquid crystal panel
CN221175022U (zh) 具有背光的感测器模组
CN111708226B (zh) 一种背光模组和显示装置
KR101409677B1 (ko) 백라이트 유닛
WO2004001970A2 (fr) Dispositif de detection et dispositif d'affichage
JPH01113706A (ja) 光回路

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CN JP KR US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP