Display methods and apparatus

• US 20060187529A1
• Filed: 10/14/2005
• Published: 08/24/2006
• 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., Steyn, Jasper Lodewyk
• Granted Patent: US 7,304,785 B2
• Time in Patent Office: Days
• US Class Current: 359/298
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

The invention relates to light modulators for use in display apparatus. In particular, the invention relates to methods for supporting and support structures for light modulators to reduce unwanted motion.

Claims

1. A display apparatus, comprising:

a modulator for selectively interacting with light in an optical path to form an image on the display apparatus;

a controllable first actuator providing a first mechanical support providing a supportive connection from a first location on the modulator to a surface over which the modulator is supported; and

a second mechanical support providing a supportive connection from a second location on the modulator to the surface,

wherein the first actuator drives the shutter in a plane substantially parallel to the surface.

2. The display apparatus of claim 1, wherein the modulator comprises a shutter.

3. The display apparatus of claim 2, wherein the shutter comprises a plurality of shutter apertures for allowing light to pass through the shutter.

4. The display apparatus of claim 2, wherein the surface defines an aperture.

5. The display apparatus of claim of claim 1, wherein the first and second mechanical supports are configured to reduce movement of the modulator out of the plane.

6. The display apparatus of claim of claim 1, wherein the first actuator is connected to the surface in at least two locations to reduce rotational movement of the modulator.

7. The display apparatus of claim of claim 1, wherein the first actuator is sufficiently stiff to reduce movement of the modulator out of the plane.

8. The display apparatus of claim of claim 1, wherein the connection between the first actuator and the modulator is sufficiently thick to reduce movement of the modulator out of the plane.

9. The display apparatus of claim 1, wherein the first actuator is coupled to the modulator at a first side of the modulator, and the second mechanical support is coupled to the modulator at a second side of the modulator.

10. The display apparatus of claim 9, wherein the first side is substantially opposite the second side.

11. The display apparatus of claim 9, wherein the first actuator is coupled to about the middle of the first side and the second mechanical support is coupled to about the middle of the second side.

12. The display apparatus of claim 1, wherein the modulator comprises a color filter.

13. The display apparatus of claim 1, wherein the modulator comprises three color filters.

14. The display apparatus of claim 1, wherein the first actuator is controlled by a passive matrix array.

15. The display apparatus of claim 1, wherein the first actuator is controlled by an active matrix array.

16. The display apparatus of claim 1, wherein at least one of the first actuator and the second mechanical support is mechanically bi-stable.

17. The display apparatus of claim 1, wherein the first actuator and the second mechanical support are between about 0.5 μ

m and about 5 μ

m wide.

18. The display apparatus of claim 1, wherein the first actuator comprises a first compliant electrode.

19. The display apparatus of claim 18, wherein the first actuator comprises a second compliant electrode proximate to the first compliant electrode for attracting the first compliant electrode, thereby driving the shutter.

20. The display apparatus of claim 18, wherein the first actuator comprises a spring connecting the first compliant electrode to one of the modulator and an anchor connected to the surface.

21. The display apparatus of claim 18, wherein the first compliant electrode has a first stiffness at a first position along the length of the first compliant member and a greater stiffness at a second position along the length of the first compliant member.

22. The display apparatus of claim 19, wherein responsive to the first and second compliant electrodes being drawn together, the modulator is moved from a first position to a second position.

23. The display apparatus of claim 1, comprising a working fluid having a dielectric constant of at least about 1.5 disposed between the modulator and the surface.

24. The display apparatus of claim 1, wherein the first actuator and a second actuator, the second actuator including the second mechanical support, drive the modulator into at least two mechanically stable positions.

25. The display apparatus of claim 1, wherein the first actuator and a second actuator, the second actuator including the second mechanical support, drive the modulator into at least three mechanically stable positions.

26. A method of manufacturing a display apparatus, comprising:

etching a first surface to form a modulator for selectively interacting with light in an optical path;

etching an actuator in the first surface connecting the modulator and an anchor, wherein the anchor and the actuator serve as a first mechanical support, physically supporting the modulator over a second surface and the actuator is configured to drive the shutter in a plane substantially parallel to the second surface;

etching a second mechanical support into first surface connecting the modulator and a second anchor, the second mechanical support physically supporting the modulator over the second surface,

wherein the first anchor and the second anchor are connected to two distinct locations on the second surface.

27. The method of claim 26, wherein the modulator, actuator and second mechanical support are formed in a single etching step.

28. The method of claim 26, wherein the modulator, actuator and second mechanical support are formed from a single layer of material.