EFFICIENT SPATIAL MODULATOR SYSTEM

• US 20080231568A1
• Filed: 03/21/2007
• Published: 09/25/2008
• Est. Priority Date: 03/21/2007
• Status: Active Grant

• Current Assignee: Spatial Photonics Incorporated (Himax Technologies Incorporated)
• Original Assignee: Spatial Photonics Incorporated (Himax Technologies Incorporated)
• Inventors: Chen, Chih-Liang, Sun, Alex Hung-Pin
• Granted Patent: US 7,903,104 B2
• Time in Patent Office: Days
• US Class Current: 345/84
• CPC Class Codes: G09G 2300/0857 Static memory circuit, e.g. flip-flop
• CPC Class Codes: G09G 2310/0289 Details of voltage level shifters arranged for use in a driving circuit
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 3/2033 with splitting one or more sub-frames corresponding to the most significant bits into two or more sub-frames
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833

Abstract

A spatial light modulator system includes an array of pixel cells each that includes two static random access memory (SRAM) devices configured to store digital data and output a first voltage signal in response to the digital data, a level shifter configured to receive the first voltage signal from at least one of the two SRAM devices and output a second voltage signal and a spatial light modulator configured to output light in an on direction or an off direction in response to the second voltage signal.

Claims

4-1. The spatial light modulator system of claim 1, wherein the spatial light modulator includes a tiltable micro mirror plate supported by a substrate and one or more electrodes under the micro mirror plate.

15. A spatial light modulator system, comprising:

an array of pixel cells each comprising;

two static random access memory (SRAM) devices each configured to store digital data and output a first voltage signal in response to the digital data;

a level shifter configured to receive the first voltage signal from at least one of the two SRAM devices and output a second voltage signal; and

a tiltable micro mirror plate supported by a substrate and one or more electrodes under the micro mirror plate, wherein the one or more electrodes are configured to receive the second voltage signal from the level shifter, wherein the micro mirror plate is configured to tilt a predetermined position in response to the second voltage signal.

16. The spatial light modulator system of claim 15, wherein the first voltage signal is in the range of about 1.3 to 2.3 volts.

17. The spatial light modulator system of claim 15, wherein the second voltage signal is in the range of about 4 to 6 volts.

18. The spatial light modulator system of claim 15, wherein the micro mirror plate is configured to receive a third voltage signal and the micro mirror plate is configured to tilt in response to the a third voltage signal and the second voltage signal.

19. The spatial light modulator system of claim 15, wherein the third voltage signal is in the range of about 20 to 40 volts.

20. The spatial light modulator system of claim 15, further comprising a multiplexer configured to select one of the two SRAM devices in response to an external signal, wherein the selected one of the two SRAM devices is configured to write data to the level shifter.

21. A method for controlling an array of spatial light modulators (SLMs) in response to a digital image, comprising:

dividing a color field of the digital image into a plurality of bit planes including a first bit plane, a second bit plane, and a third bit plane;

displaying the first bit plane by controlling an SLM in the array to a predetermined position;

writing data associated with the second bit plane to a first static random access memory (SRAM) device and data associated with the third bit plane to a second SRAM device during the displaying of the first bit plane;

after the displaying of the first bit plane, displaying the second bit plane by controlling the SLM in the array to the predetermined position in accordance with the data written to the first SRAM device; and

after the displaying of the second bit plane, displaying the third bit plane by controlling the SLM in the array to the predetermined position in accordance with the data written to the second SRAM device.

22. The method of claim 21, wherein the first bit plane defines a first period of time that the SLM is to be controlled at the predetermined position and the second bit plane defines a second period of time that the SLM is to be controlled at the predetermined position.

23. The method of claim 22, wherein the first period of time is two times or longer than the second period of time.

24. The method of claim 23, wherein the first period of time is four times or longer than the second period of time.

25. The method of claim 21, further comprising:

sending a first voltage signal from the one of two SRAM devices to a level shifter in response to the data associated with the second bit plane; and

sending a second voltage signal from the level-shifter to the SLM in response to the first voltage signal to control the SLM to the predetermined position.

26. The method of claim 25, wherein the first voltage signal is in the range of about 1.3 to 2.3 volts.

27. The method of claim 25, wherein the second voltage signal is in the range of about 4 to 6 volts.

28. The method of claim 21, wherein the spatial light modulator includes a micro mirror tiltable about a hinge supported by a substrate and one or more electrodes under the micro mirror plate on the substrate.

29. The method of claim 28, further comprising:

sending a first voltage signal from the one of two SRAM devices to a level shifter coupled to the micro mirror in response to the data associated with the second bit plane; and

sending a second voltage signal from the level-shifter to the one or more electrodes in response to the first voltage signal to control the micro mirror to the predetermined position.

30. The method of claim 29, further comprising sending a third voltage signal to the micro mirror, wherein the third voltage signal is in the range of about 15 to 50 volts.

31. The method of claim 30, further comprising tilting the micro mirror in response to the third voltage signal or the second voltage signal.