Display methods and apparatus

• US 20070195026A1
• Filed: 04/12/2007
• Published: 08/23/2007
• Est. Priority Date: 02/23/2005
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Barton, Roger, Lewis, Stephen, McAllister, Abraham, Hagood, Nesbitt
• Granted Patent: US 7,839,356 B2
• Time in Patent Office: Days
• US Class Current: 345/85
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 26/04 by periodically varying the intensity of light, e.g. using choppers shutters, diaphragms for cameras G03B9/00; devices for eliminating or reducing the effect of flicker in projection systems G03B21/40
• CPC Class Codes: G09G 2300/0814 used for selection purposes, e.g. logical AND for partial update
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/088 using a non-linear two-terminal element
• CPC Class Codes: G09G 2310/02 Addressing, scanning or driving the display screen or processing steps related thereto
• CPC Class Codes: G09G 2310/0218 with collection of electrodes in groups for n-dimensional addressing
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 2310/06 Details of flat display driving waveforms
• CPC Class Codes: G09G 2310/063 Waveforms for resetting the whole screen at once
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3433 using light modulating elements actuated by an electric field and being other than liquid crystal devices and electrochromic devices using liquid crystal devices G09G3/36; using electrochromic devices G09G3/38

Abstract

The invention relates to methods and apparatus for forming images on a display utilizing a control matrix to control the movement of MEMs-based light modulators.

Claims

1. A direct-view display comprising:

a transparent substrate;

an array of MEMS light modulators formed on the transparent substrate;

a control matrix formed on the transparent substrate for transmitting data to the array; and

a controller for controlling a state of each of the light modulators in the array including a timing controller for coordinating application of voltages to at least one lamp to illuminate the MEMS light modulators to display a first sub-frame image corresponding to a first color in an image frame for a first duration and to display a second sub-frame image corresponding to the first color of the same image frame for a second duration, wherein the first duration is different than the second duration.

2. The direct view display of claim 1, wherein the controller controls the intensity with which the at least one lamp illuminates the array.

3. The direct view display of claim 1, wherein the control matrix comprises a plurality of memory elements corresponding to respective MEMS light modulators.

4. The direct view display of claim 3, wherein the timing controller coordinates the application of voltages such that the at least one lamp remains on until addressing data is stored in the memory elements corresponding to each of the respective MEMS light modulators in the array.

5. The direct view display of claim 1, wherein the timing controller coordinates the application of voltages such that the at least one lamp remains off during actuation of the MEMS light modulators.

6. The direct view display of claim 1, wherein the timing controller coordinates the application of voltages such that sub-frame images are displayed according to a predetermined sequence.

7. The direct view display of claim 1, wherein the timing controller coordinates the application of voltages such that the at least one lamp remains off until addressing data is communicated to all MEMS light modulators in the array.

8. The direct view display of claim 1, comprising a global actuation driver in communication with the controller for substantially simultaneously applying a global actuation voltage to MEMS light modulators in multiple rows and multiple columns of the array.

9. The direct view display of claim 1, comprising a lamp driver in communication with the controller for providing a voltage sufficient to illuminate the at least one lamp.

10. The direct view display of claim 1, comprising a plurality of independently controlled lamp drivers in communication with the controller for providing voltages sufficient to illuminate corresponding ones of the at least one lamp.

11. The direct view display of claim 1, wherein the timing controller varies the duration for which the first and second sub-frame images is illuminated based on a respective significances associated with the first and second sub-frame images.

12. The direct view display of claim 1, comprising a scan driver in communication with the controller for applying a write enabling voltage to rows of MEMS light modulators in the array.

13. The direct view display of claim 1, wherein the timing controller coordinates a row addressing sequence governing the order in which rows in the array are addressed.

14. The direct view display of claim 13, wherein the row addressing sequence includes addressing rows in the array sequentially.

15. The direct view display of claim 13, wherein the row addressing sequence includes addressing the rows non-sequentially.

16. The direct-view display of claim 1, comprising a display interface for processing an incoming image signal into addressing data based on a gray scale process executed by the direct-view display.

17. The direct view display of claim 16, wherein the display interface processes an incoming image signal into addressing data based on a coded time division gray scale process.

18. The direct view display of claim 16, wherein the display interface processes an incoming image signal into addressing data based on a binary weighted coded time division gray scale process.

19. The direct view display of claim 16, wherein the display interface processes an incoming image signal into addressing data based on an illumination gray scale process.

20. The direct view display of claim 16, wherein the timing controller coordinates the application of voltages such that the at least one lamp remains off until all MEMS light modulators in the array actuate according to the addressing data.

21. The direct-view display of claim 1, wherein the display interface derives a plurality of sub-frame images, including the first and second sub-frame images, based on the image signal.

22. The direct view display of claim 1, wherein the timing controller coordinates applying data voltages to the control matrix with the application of voltages to the at least one lamp.

23. The direct view display of claim 22, comprising a data driver in communication with the controller for applying a first of the data voltages to a column of light modulators in the array.

24. The direct view display of claim 23, comprising a second data driver in communication with the controller for applying a second of the data voltages to the column of light modulators, wherein the voltage applied by the data driver drives at least one light modulator in the column into a first state and the second data voltage applied by the second data driver drives at least one light modulator in the column into a second, opposing state.

25. The direct view display of claim 23, comprising a frame buffer.

26. The direct view display of claim 25, wherein the controller feeds data to the data driver from the frame buffer.

27. The direct view display of claim 22, comprising an actuation driver in communication with the controller for applying actuation voltages to a plurality of MEMS light modulators in the array.

28. The direct view display of claim 27, wherein the actuation driver substantially simultaneously applies actuation voltages to MEMS light modulators in a multiple columns and multiple rows of the array.

29. The direct view display of claim 27, wherein the magnitude of the actuation voltage is at least four times the magnitude of the data voltages.