Control system for display panels

• US 6,320,568 B1
• Filed: 12/27/1994
• Issued: 11/20/2001
• Est. Priority Date: 12/31/1990
• Status: Expired due to Term

• Current Assignee: Kopin Corporation
• Original Assignee: Kopin Corporation
• Inventors: Zavracky, Matthew
• Primary Examiner(s): WU, XIAO MIN
• Application Number:
  US08/364,070
• Time in Patent Office: 2,520 Days
• Field of Search: 345/98, 345/99, 345/100, 345/87, 345/89, 345/93, 345/96, 345/101, 345/102, 345/103, 345/207, 345/205, 345/204, 345/209, 359/54, 359/55, 348/792, 349/72
• US Class Current: 345/101
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 2027/0198 System for aligning or maintaining alignment of an image in a predetermined direction
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/13613 the semiconductor element being formed on a first substrate and thereafter transferred to the final cell substrate
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon
• CPC Class Codes: G06F 3/147 using display panels
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0259 with use of an analog or digital ramp generator in the column driver or in the pixel circuit
• CPC Class Codes: G09G 2310/0281 Arrangement of scan or data electrode driver circuits at the periphery of a panel not inherent to a split matrix structure
• CPC Class Codes: G09G 2320/0233 : Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/041 : Temperature compensation
• CPC Class Codes: G09G 2320/043 : Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2340/0464 : Positioning
• CPC Class Codes: G09G 2360/02 : Graphics controller able to handle multiple formats, e.g. input or output formats
• CPC Class Codes: G09G 2360/145 : the light originating from the display screen
• CPC Class Codes: G09G 2370/04 : Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 2370/042 : for monitor identification
• CPC Class Codes: G09G 3/006 : Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/2007 : Display of intermediate tones
• CPC Class Codes: G09G 3/2014 : by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/30 : using electroluminescent panels
• CPC Class Codes: G09G 3/36 : using liquid crystals
• CPC Class Codes: G09G 3/3607 : for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3614 : Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01L 21/8221 : Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 2221/68359 : used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 25/0756 : Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 27/0688 : Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/1214 : comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/156 : two-dimensional arrays
• CPC Class Codes: H01L 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78603 : characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78612 : for preventing the kink- or the snapback effect, e.g. discharging the minority carriers of the channel region for preventing bipolar effect
• CPC Class Codes: H01L 29/78618 : characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/78633 : with a light shield
• CPC Class Codes: H01L 29/78645 : with multiple gate
• 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 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0062 : for devices with an active region comprising only III-V compounds
• CPC Class Codes: H01S 5/423 : having a vertical cavity
• CPC Class Codes: H04N 3/127 : using liquid crystals
• CPC Class Codes: H04N 5/70 : Circuit details for electroluminescent devices
• CPC Class Codes: H04N 5/74 : Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 5/7441 : the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 5/7491 : of head mounted projectors
• CPC Class Codes: H04N 9/3105 : for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/312 : Driving therefor driving of electronic spatial light modulators in displays other than projection devices G09G3/34, G09G3/36; control of liquid crystal elements G02F1/133; control of micromechanical modulators G02B26/08
• CPC Class Codes: H04N 9/3141 : Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3182 : Colour adjustment, e.g. white balance, shading or gamut white balance per se H04N9/73; control of amplitude of colour signals H04N9/68; colour control circuits for displays in general G09G5/02, G09G3/2003, G09G3/3607
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces

Abstract

A control apparatus for an active matrix liquid crystal display device is fabricated with the active matrix as a single integrated SOI circuit. The control apparatus and the active matrix are lifted from a silicon substrate and transferred to a glass substrate as a single piece. The control apparatus comprises a video interface, a column driver, and dual row drivers. The video interface operates the active matrix as a multiple-frequency scanning display device. The column driver comprises dual shift register arrays, one array coupled to the even columns and the other array coupled to the odd columns. The even and odd columns operate at opposite polarities. The respective polarities are reversed on every frame by a polarity switch the polarity switch coupled to a video signal amplifier. The control apparatus further comprises sensors for generating a gray-scale feedback signal to adjust the amplifier gain. The sensors comprise a temperature sensor within the active matrix and a light sensor measuring light transmission through the liquid crystal material.

Claims

1. A control apparatus for driving an active matrix liquid crystal display in response to a stream of video signals from a video source, the display having an array of pixel transistors between a substrate and an opposing substrate, the array being addressed by a plurality of row lines and a plurality of column lines, the apparatus comprising:

an adhesive layer bonding a single crystal silicon layer to the substrate;

a video interface for converting a set of synchronization signals in the video signals to a group of control signals comprising a column control signal, a row control signal, and a polarity control signal;

a first select scanner and a second select scanner disposed within the single crystal silicon layer and coupled to the video interface and responsive to the row control signal, each select scanner coupled to each row line at opposite sides of the active matrix region with each select scanner generating a simultaneous select line drive signal to drive the pixel transistors addressed by the select row line wherein each addressed pixel transistor receives at least a portion of the simultaneous drive signal from each select scanner;

a video polarity circuit coupled to the video source and the video interface and responsive to the polarity control signal, the polarity circuit generating an intensity signal to be applied to the pixel transistors addressed by the select row line, the polarity of the intensity signal being reversed in response to the polarity control signal;

a data scanner disposed within the single crystal silicon layer and coupled to the video interface, the video polarity circuit and the column lines, the data scanner driving the pixel transistors with the intensity signal in response to the column control signal; and

a temperature sensor positioned between the substrate and the opposing substrate and formed with the single crystal silicon layer for sensing the temperature of the active matrix liquid crystal display.

2. The control apparatus of claim 1 wherein the data scanner comprises an odd column data scanner for driving the odd columns of the active matrix and an even column data scanner for driving the even columns of the active matrix.

3. The control apparatus of claim 1 further comprising an encoder coupled between the video source and the video polarity circuit, the encoder generating a superposed analog intensity signal from a video source RGB data signal.

4. The control apparatus of claim 3 wherein the encoder maps the RGB data signal to a superposed color analog signal.

5. The control apparatus of claim 3 wherein the encoder maps the RGB data signal to a gray-scale analog signal.

6. The control apparatus of claim 1 further comprising a temperature measurer coupled to the temperature sensor for generating a temperature feedback signal to adjust the intensity signal in response to the temperature data.

7. The control apparatus of claim 6 wherein the video polarity circuitry is coupled to the temperature measurer and comprises an amplifier, a gain of the amplifier being responsive to the temperature feedback signal.

8. The control apparatus of claim 5 further comprising at least one light sensor located between the substrates for signaling relative light transmission changes through the liquid crystal.

9. The control apparatus of claim 8 further comprising a light meter coupled to the light sensor for generating a light feedback signal to adjust the intensity signal in response to the light transmission change.

10. The control apparatus of claim 9 wherein the video polarity circuit is coupled to the light meter and comprises an amplifier, a gain of the amplifier being responsive to the light feedback signal.

11. The control apparatus of claim 1 wherein the video polarity circuit generates an odd column video signal for driving odd columns of the active matrix and an even column video signal for driving even columns of the active matrix, the odd column video signal and the even column video signal being of opposite polarities.

12. The control apparatus of claim 1 wherein the select scanners comprise respective shift registers, the shift registers being shifted to sequentially enable a select row line in response to the row control signal.

13. The control apparatus of claim 1 wherein the video interface comprises a phase-locked loop circuit for tracking changes in the synchronization signals.

14. The control apparatus of claim 1 wherein the active matrix region has at least 640 column lines and at least 480 row lines.

15. The control apparatus of claim 14 wherein the active matrix region has at least 1024 column lines and at least 768 row lines.

16. The control apparatus of claim 1 wherein the device layer is an SOI structure.

17. A control apparatus for adjusting a gray scale video signal of an active matrix liquid crystal display panel, the panel having an active matrix layer fabricated as a single crystal silicon layer of a silicon-on-insulator (SOI) structure, including a single crystal layer of silicon, comprising:

a sensor formed with the single crystal silicon layer of the SOI structure for sensing temperature and light, the sensor generating a data signal in response to the temperature of the active matrix and the light transmittance of the liquid crystal material;

a measurer for measuring the data signal from the sensor and generating a feedback signal in response to the data signal;

an amplifier coupled to the gray-scale video signal and the measurer, a gain of the amplifier being responsive to the feedback signal, the amplifier amplifying the video signal by the gain which is dependent on at least one property of the liquid crystal.

18. The control apparatus of claim 17 wherein the sensor comprises at least one real-time light sensor and at least one real-time temperature sensor.

19. The control apparatus of claim 18 further comprising at least one light sensor generating a signal representing the light transmittance through a black pixel and at least one light sensor generating a signal representing the light transmittance through a white pixel.

20. The control of apparatus of claim 17 wherein the amplifier gain is nonlinear.

21. A control apparatus for driving an active matrix liquid crystal display in response to a stream of video signals from a video source, the display having an array of pixel transistors in between a substrate and an opposing substrate, the array being in a single crystal silicon layer of a silicon-on-insulator (SOI) structure, the pixel transistors addressed by a plurality of row lines and column lines, the apparatus comprising:

an adhesive layer bonding the single crystal silicon layer to a substrate;

a first select scanner and a second select scanner in the single crystal silicon layer and coupled to the video source and the row lines for addressing a select row of pixel transistors, each select scanner coupled to each row line at opposite sides of the active matrix region with each select scanner generating a simultaneous drive signal on the selected row line wherein each pixel transistor on the selected row line receives a portion of the drive signal from each select scanner;

a data scanner in the single crystal silicon layer and coupled to the video source and the column line for driving the pixel transistors on the select row of pixel transistors in response to the video signals; and

a temperature sensor formed with the single crystal layer between the substrate and the opposing substrate for sensing the temperature of the active matrix liquid crystal display.

22. The control apparatus of claim 21 further comprising a video polarity circuit in the SOI layer and coupled to the video source and the data scanner for generating an intensity signal for actuating the pixels in response to the video signals, the polarity of the intensity signal being reversed at a periodic rate.

23. The control apparatus of claim 22 wherein the periodic rate is once every video frame.

24. The control apparatus of claim 22 wherein the video polarity circuit generates an odd column intensity signal and an even column intensity signal for driving alternate columns of pixels with reversed polarity intensity signals.

25. The control apparatus of claim 21 further comprising a temperature measurer coupled to the temperature sensor for generating a temperature feedback signal to modify the video signal in response to the temperature of the active matrix region.

26. The control apparatus of claim 21 further comprising a light sensor disposed between the substrate and the opposing substrate for signaling relative light transmission changes through the liquid crystal.

27. The control apparatus of claim 26 further comprising a light meter coupled to the light sensor for generating a light feedback signal to modify the video signal in response to the light transmission change.

28. The control apparatus of claim 21 wherein the select scanners comprise respective shift registers, the shift registers being shifted to sequentially address a select row line.

29. The control apparatus of claim 21 wherein the active matrix region includes an array of pixel electrodes registered to the array of pixel transistors, wherein the pixel electrodes are patterned to reduce transmission loss through the pixel electrode.

30. The control apparatus of claim 29 wherein the pixel electrode pattern is a grid pattern.

31. The control apparatus of claim 30 wherein the patterned pixel electrode is at least one strip of semiconductor material having a wide of about 3 microns.

34. The control apparatus of claim 26 further comprising a video polarity circuitry coupled to the temperature measurer and comprises an amplifier, a gain of the amplifier being responsive to the temperature feedback signal.

32. A control apparatus for driving an active matrix liquid crystal display in response to a stream of video signals from a video source, the display having an array of pixel transistors between a first substrate and a second substrate, the array being addressed by a plurality of row lines and a plurality of column lines, the apparatus comprising:

an adhesive layer bonding a semiconductor device layer to a substrate, the device layer including the liquid crystal between the first substrate and the second substrate;

a row driver;

a column driver; and

a temperature sensor between the first and the second substrates for sensing the temperature of the active matrix liquid crystal display.

33. The control apparatus of claim 32 further comprising a temperature measurer coupled to the temperature sensor for generating a temperature feedback signal to adjust the intensity signal in response to the temperature data.

35. The control apparatus of claim 32 further comprising at least one light sensor disposed between the first substrate and the second substrate for signaling relative light transmission changes through the liquid crystal and a light meter coupled to the light sensor for generating a light feedback signal to adjust the intensity signal in response to the light transmission change.

36. A control apparatus for adjusting a gray-scale video signal of an active matrix liquid crystal display panel, the panel having an active matrix layer fabricated with a single crystal layer of silicon of a silicon-on-insulator (SOI) structure, comprising:

a sensor formed with the single crystal silicon layer of the SOI structure that senses a property of the liquid crystal, the sensor generating a data signal in response to the property of the liquid crystal material;

a temperature measuring circuit that receives the data signal from the sensor and generates a feedback signal in response to the data signal; and

an amplifier coupled to the gray-scale video signal and the measuring circuit, a gain of the amplifier being responsive to the feedback signal, the amplifier amplifying the video signal by the gain.

37. The control apparatus of claim 36 wherein the sensor comprises at least one real-time temperature sensor.

38. The control apparatus of claim 36 wherein the sensor comprises at least one light sensor generating a signal representing the light transmittance through a black pixel and at least one light sensor generating a signal representing the light transmittance through a white pixel.