Light valve device

• US 6,304,243 B1
• Filed: 10/06/1993
• Issued: 10/16/2001
• Est. Priority Date: 10/12/1992
• Status: Expired due to Fees

• Current Assignee: Seiko Instruments Incorporated (Seiko Group)
• Original Assignee: Seiko Instruments Incorporated (Seiko Group)
• Inventors: Takasu, Hiroaki, Sakurai, Atsushi, Takahashi, Kunihiro, Kondo, Kenichi, Yamazaki, Tsuneo
• Primary Examiner(s): Mengistu, Amare
• Application Number:
  US08/132,692
• Time in Patent Office: 2,932 Days
• Field of Search: 345/87, 345/90, 345/92, 345/94, 345/98, 345/100, 345/102, 345/103, 345/205, 345/206, 359/54, 359/55-61
• US Class Current: 345/100
• CPC Class Codes: G02F 1/133354 Arrangements for aligning or assembling substrates
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/135 Liquid crystal cells structurally associated with a photoconducting or a ferro-electric layer, the properties of which can be optically or electrically varied G02F1/133348 takes precedence
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 2202/105 single crystal Si
• CPC Class Codes: G09G 2310/027 Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/30107 Inductance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H04N 13/158 : Switching image signals
• CPC Class Codes: H04N 13/189 : Recording image signals; Reproducing recorded image signals
• CPC Class Codes: H04N 13/194 : Transmission of image signals
• CPC Class Codes: H04N 13/239 : using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/324 : Colour aspects
• CPC Class Codes: H04N 13/363 : using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 13/398 : Synchronisation thereof; Control thereof

Abstract

A highly integrated light valve is formed with a composite substrate formed of a quartz substrate and a monocrystalline silicon thin film layer bonded to the quartz substrate, in which an X driving circuit and a Y driving circuit are integrated utilizing very large scale integration processing. Driving electrodes are arranged in a matrix format on the composite substrate for providing signals output from the X driving circuit and the Y driving circuit to respective transistors and display pixel electrodes arranged at each intersection of the driving electrodes in the matrix. A control circuit for supplying timing signals to the X driving circuit and the Y driving circuit and a display data generating circuit for generating display data in order to display an image are also integrated on the composite substrate. A light source element driving circuit for driving a light source element is provided thereon for projecting a displayed image. A liquid crystal layer is sealed in a gap between the composite substrate and a second, opposed substrate with a sealing agent. The sealing agent is, for example, a resin which is stiffened by ultraviolet radiation and is supplied along a predetermined seal region. The present invention provides an improved structure for a light valve device having a high reliability, compact size, high pixel density and high resolution.

Claims

1. A light valve device comprising:

a composite substrate comprising a semiconductor monocrystalline thin film mounted on an electrically insulating substrate, the monocrystalline thin film comprising a thinned single crystal semiconductor wafer;

a second substrate opposed to and spaced from the composite substrate;

an electrooptic material interposed between the composite substrate and the second substrate;

a pixel section and a driving circuit section each being formed on the composite substrate, the driving circuit section being formed in the semiconductor monocrystalline thin film and the pixel section including an X electrode group, a Y electrode group crossing the X electrode group, and a thin film transistor formed in the monocrystalline thin film and a pixel electrode both disposed proximate each intersection of respective X electrodes and Y electrodes;

wherein the driving circuit section comprises an X electrode driving circuit for supplying display data signals to the X electrode group, a Y electrode driving circuit for supplying scanning signals to the Y electrode group, a control circuit for supplying timing signals to the X electrode driving circuit and the Y electrode driving circuit, and a display data generating circuit for generating display data signals in accordance with an input image signal and for supplying the display data signals to the X electrode driving circuit;

wherein the electrooptic material becomes excited when the display data signals and the scanning signals selectively energize the pixel electrodes by activation of respective thin film transistors; and

wherein the display data generating circuit comprises an RGB conversion circuit and a synchronization separation circuit, wherein the RGB conversion circuit is operable to receive the input image signal and to output RGB display signals to the X electrode driving circuit, and the synchronization separation circuit is operative to provide synchronization signals to the control circuit.

2. A light valve device as claimed in claim 1, wherein the display data generating circuit comprises an A/D conversion circuit for converting video signals contained in the input image signal into digital video signals and for supplying the digital video signals to the X electrode driving circuit, and wherein the driving circuit section further comprises a D/A conversion circuit for converting the digital video signals into analog display data signals.

3. A light valve device as claimed in claim 1;

wherein the display data generating circuit further comprises a timing pulse generating circuit and a video signal processing circuit, the timing pulse generating circuit being operative to generate synchronization signals and to apply the synchronization signals to the video signal processing circuit, and the video signal processing circuit being operative to receive input image signals from an image detecting means and to supply composite video signals to the RGB conversion circuit.

4. A light valve device comprising:

a composite substrate comprising a semiconductor monocrystalline thin film adhered to an electrically insulating substrate, the monocrystalline thin film comprising a thinned single crystal semiconductor wafer;

a second substrate opposed to and spaced from the composite substrates;

an electrooptic material interposed between the composite substrate and the second substrate;

a pixel section and a driving circuit section formed in the semiconductor monocrystalline thin film, the pixel section including an X electrode group, a Y electrode group crossing the X electrode group, and a thin film transistor and a pixel electrode both disposed proximate each intersection of respective X electrodes and Y electrodes, and the driving circuit section comprising an X electrode driving circuit for supplying display data signals to the X electrode group, and a Y electrode driving circuit for supplying scanning signals to the Y electrode group; and

a display data generating circuit formed on the composite substrate for generating display data signals in accordance with an input image signal and for supplying the display data signals to the X driving circuit, and comprising a color conversion circuit for providing color display signals to the X electrode driving circuit in accordance with an input image signal;

wherein the synchronization separation circuit outputs synchronization signals to the control circuit in accordance with the input image signal, and the control circuit outputs timing signals, to the driving circuit section.

5. A light valve device according to claim 4;

further comprising a control circuit formed on the composite substrate for providing timing signals to the driving circuit section.

6. A light valve device according to claim 4;

further comprising a light source formed on the composite substrate, and light source driving means for driving the light source.

7. A light valve device according to claim 4;

wherein the display data generating circuit further comprises analog-to-digital converting means for converting an input analog video signal into a digital video signal, and wherein the driving circuit section includes a digital-to-analog converting means for converting the digital video signal into an analog display data signal.

8. A light valve device according to claim 4;

wherein the composite substrate and the second substrate are affixed by means of a seal region to provide a predetermined spacing between the substrates, and the electrooptic material is sealed in the seal region, wherein the seal region overlaps at least part of the driving circuit section formed on the composite substrate.

9. A light valve device according to claim 4;

wherein the driving circuit section includes a pair of X electrode driving circuits disposed on opposite sides of the pixel section on the composite substrate.