Circuits for controlling display apparatus

• US 9,177,523 B2
• Filed: 08/26/2013
• Issued: 11/03/2015
• Est. Priority Date: 02/23/2005
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Hagood, Nesbitt W., Lewis, Stephen R., McAllister, Abraham, Barton, Roger W.
• Primary Examiner(s): PHAM, VIET DAVID
• Application Number:
  US13/975,841
• Publication Number:
  US 20130342522A1
• Time in Patent Office: 799 Days
• Field of Search: 345/84, 345/108, 345/204, 359/290
• US Class Current: 1/1
• CPC Class Codes: G09G 2300/0838 with level shifting
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2300/0866 by means of changes in the pixel supply voltage
• CPC Class Codes: G09G 2300/0871 with level shifting
• 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 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833
• CPC Class Codes: G09G 5/001 Arbitration of resources in a display system, e.g. control of access to frame buffer by video controller and/or main processor

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 display apparatus comprising:

a substrate;

an array of pixels formed on the substrate including, for each pixel, a light modulator including a first movable electrostatic actuator; and

a voltage regulator that limits variation in a voltage across the first movable electrostatic actuator, wherein the variation in the voltage is caused by a movement of at least a portion of the first movable electrostatic actuator.

2. The display apparatus of claim 1, wherein the voltage regulator includes a display driver including a DC voltage source.

3. The display apparatus of claim 1, wherein the light modulators are controlled by active circuitry.

4. The display apparatus of claim 3, wherein the active circuitry includes at least one TFT.

5. The display of claim 4, wherein the active circuitry includes, for each pixel, a write-enabling interconnect for enabling the pixel to respond to a data voltage and a data voltage interconnect for applying the data voltage to a data switch, thereby controlling the state of the light modulator of the pixel.

6. The display apparatus of claim 5, comprising for a pixel, an actuation voltage interconnect, distinct from the data voltage interconnect, for connecting the first movable electrostatic actuator to the display driver.

7. The display apparatus of claim 6, comprising, for a pixel, a switch, other than the data switch, for controlling the application of the voltage output by the display driver to the first movable electrostatic actuator.

8. The display apparatus of claim 1, wherein each pixel includes a voltage regulator.

9. The display apparatus of claim 8, wherein the voltage regulator includes a capacitor in electrical communication with the first electrostatic actuator.

10. The display apparatus of claim 1, comprising a voltage inverter.

11. The display apparatus of claim 10, wherein the voltage inverter includes a CMOS circuit.

12. The display apparatus of claim 1, wherein each light modulator includes a second electrostatic actuator for applying a force opposing a force applied by the first actuator.

13. The display apparatus of claim 12, comprising, for a pixel, a flip-flop electrically coupling the first movable electrostatic actuator and the second electrostatic actuator.

14. The display apparatus of claim 13, comprising, for a pixel, a cross-coupled inverter electrically coupling the first movable electrostatic actuator and the second electrostatic actuator.

15. The display apparatus of claim 1, wherein the light modulators includes MEMS shutter-based light modulators.

16. A display apparatus comprising:

an array of pixels including for each pixel, a light modulator; and

active circuitry formed on a substrate for addressing the light modulators of the array, wherein for each pixel, the active circuitry includes a CMOS circuit comprising a flip-flop for controlling application of an actuation voltage to the light modulator.

17. The display apparatus of claim 16, wherein the active circuitry includes a control matrix having at least one TFT.

18. The display apparatus of claim 16, wherein the CMOS circuit includes at least one of a voltage inverter and a level shifting inverter.

19. The display apparatus of claim 16, wherein the flip-flop electrically couples opposing actuators of the light modulator.

20. The display apparatus of claim 16, wherein the light modulator includes at least one of a shutter-based light modulator, a light tap-based light modulator, and an electrowetting-based light modulator.