Control of MEMS and light modulator arrays

• US 6,741,384 B1
• Filed: 04/30/2003
• Issued: 05/25/2004
• Est. Priority Date: 04/30/2003
• Status: Expired due to Term

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Ghozeil, Adam L, Piehl, Arthur, Fricke, Peter J., Martin, Eric T., Przybyla, James R.
• Primary Examiner(s): Sugarman, Scott J.
• Assistant Examiner(s): HANIG, RICHARD E
• Application Number:
  US10/429,144
• Time in Patent Office: 391 Days
• Field of Search: 359/291, 359/298, 359/315, 359/579, 359/584, 345/84, 345/85
• US Class Current: 359/291
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• 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 3/2011 by amplitude modulation
• 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

An array of MEMS devices having column lines and row lines, such as a light modulator array, is controlled in response to an input signal by providing a number of discrete voltages, multiplexing from the discrete voltages a selected voltage to be applied to each MEMS device of the array, and enabling application of the selected discrete voltage to each MEMS device of the array.

Claims

1. A method for controlling, in response to an input signal, an array of MEMS devices of the type having column lines and row lines for selecting a particular MEMS device of the array, the method comprising the steps of:

a) providing a number of discrete voltages; and

b) responsive to the input signal, multiplexing from the discrete voltages a selected discrete voltage to be applied to each MEMS device of the array; and

c) enabling application of the selected discrete voltage to each MEMS device of the array.

2. The method of claim 1, wherein the discrete voltages are analog reference voltages.

3. The method of claim 1, wherein each MEMS device of the array comprises a pixel cell of a light modulator.

4. A method for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the method comprising the steps of:

a) providing a number of discrete voltages; and

b) responsive to the input signal, multiplexing from the discrete voltages a selected discrete voltage to be applied to each pixel of the array; and

c) enabling application of the selected discrete voltage to each pixel of the array.

5. The method of claim 4, wherein the discrete voltages are analog reference voltages.

6. A method for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the method comprising the steps of:

a) providing a number of discrete voltages; and

for each pixel of the array,

b) selecting from the discrete voltages a voltage to be applied to the pixel;

c) applying the selected voltage to the column line of the pixel; and

d) enabling application of the selected voltage to the pixel by selecting the row line for the pixel.

7. The method of claim 6, wherein the discrete voltages are analog reference voltages.

8. The method of claim 6, wherein the voltage-selecting step b), the voltage-applying step c), and the enabling step d) are performed for all pixels of the light modulator array substantially simultaneously.

9. A method for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the method comprising the steps of:

a) providing a number of discrete voltages; and

for each pixel of the array,

b) selecting from the discrete voltages a voltage to be applied to the pixel;

c) applying the selected voltage to the row line of the pixel; and

d) enabling application of the selected voltage to the pixel by selecting the column line for the pixel.

10. The method of claim 9, wherein the discrete voltages are analog reference voltages.

11. The method of claim 9, wherein the voltage-selecting step b), the voltage-applying step c), and the enabling step d) are performed for all pixels of the light modulator array substantially simultaneously.

12. A method for controlling a light modulator array having pixel modulation elements adapted to be responsive to analog voltage signals, the method comprising the steps of:

a) providing a number of column lines and a number of row lines, each combination of a column line and a row line being adapted to select a pixel;

b) providing a number of discrete voltages; and

for each pixel of the array,

c) selecting from the discrete voltages a voltage to be applied to the pixel;

d) applying the selected voltage to the column line of the pixel; and

e) enabling application of the selected voltage to the pixel by selecting the row line for the pixel.

13. The method of claim 12, wherein the voltage-selecting step c), the voltage-applying step d), and the enabling step e) are performed for all pixels of the light modulator array substantially simultaneously.

14. The method of claim 12, wherein each discrete voltage corresponds to a gray level.

15. The method of claim 12, wherein each discrete voltage corresponds to a unique combination of hue, saturation, and intensity of color.

16. Apparatus for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the apparatus comprising:

a) a number of discrete voltage sources;

b) a multiplexer responsive to the input signal for multiplexing from the discrete voltage sources a selected voltage to be applied to each pixel of the array; and

c) one or more gates for enabling application of the selected discrete voltage to each pixel of the array.

17. The apparatus of claim 16, further comprising a capacitor coupled to the gate.

18. The apparatus of claim 16, wherein the gate is controlled by a row line.

19. The apparatus of claim 16, further comprising a plurality of voltage select blocks, each voltage select block being coupled to a column line.

20. The apparatus of claim 16, wherein the gate is controlled by a column line.

21. The apparatus of claim 16, further comprising a plurality of voltage select blocks, each voltage select block being coupled to a row line.

22. The apparatus of claim 16, wherein each discrete voltage source is a digital-to-analog converter (DAC).

23. Apparatus for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the apparatus comprising:

a) a number of discrete voltage sources;

b) a multiplexer responsive to the input signal for multiplexing from the discrete voltage sources a selected voltage to be applied to each pixel of the array, the multiplexer comprising a plurality of voltage select blocks, each voltage select block being coupled to a column line; and

c) a plurality of gates for enabling application of the selected discrete voltage to each pixel of the array, each gate being coupled to a row line.

24. Apparatus for controlling, in response to an input signal, a light modulator array of the type having column lines and row lines for selecting a pixel of the array, the apparatus comprising:

a) a number of discrete voltage sources;

b) a multiplexer responsive to the input signal for multiplexing from the discrete voltage sources a selected voltage to be applied to each pixel of the array, the multiplexer comprising a plurality of voltage select blocks, each voltage select block being coupled to a row line; and

c) a plurality of gates for enabling application of the selected discrete voltage to each pixel of the array, each gate being coupled to a column line.

25. A controller for a light-modulator array having a plurality of MEMS devices, the controller comprising:

a) means for providing a number of discrete analog voltages;

b) means for selecting from the discrete voltages an analog voltage to be applied to each MEMS device; and

c) means for applying the selected analog voltage to each MEMS device.

26. The controller of claim 25, further comprising:

d) means for gating application of the selected analog voltage to each MEMS device.

27. The controller of claim 25, wherein each MEMS device of the array comprises a pixel cell of a light modulator.