Micromirror and post arrangements on substrates

• US 7,362,493 B2
• Filed: 08/30/2005
• Issued: 04/22/2008
• Est. Priority Date: 10/30/2003
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Huibers, Andrew, Patel, Satyadev
• Primary Examiner(s): Mack; Ricky
• Assistant Examiner(s): Dinh; Jack
• Application Number:
  US11/216,930
• Publication Number:
  US 20060018003A1
• Time in Patent Office: 966 Days
• Field of Search: 329290-292, 329/295, 329/298
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A micromirror of a micromirror array of a spatial light modulator used in display systems comprises a mirror plate attached to a hinge that is supported by two posts formed on a substrate. Also the mirror plate is operable to rotate along a rotation axis that is parallel to but offset from a diagonal of the mirror plate when viewed from the top. An imaginary line connecting the two posts is not parallel to either diagonal of the mirror plate.

Claims

1. A spatial light modulator comprising:

a rectangular array of micromirrors on a substrate having four predominate sides that form a rectangular shape, each micromirror having four predominant sides, wherein each side is neither parallel nor perpendicular to the edges of the rectangular array; and

wherein each side of the micromirror is at an angle of from 5°

degrees to 25°

degrees to the two sides of the rectangular substrate.

2. The spatial light modulator of claim 1, wherein each micromirror is in a shape of a rectangle, square, trapezoid or rhombus.

3. The spatial light modulator of claim 2, wherein the micromirror is in a shape of square.

4. The spatial light modulator of claim 1, wherein the plurality of posts consists of two posts.

5. The spatial light modulator of claim 1, wherein the substrate has four predominant sides that form a rectangular shape;

and wherein each side of the micromirror is at an angle of from 10°

degrees to 20°

degrees to the two sides of the rectangular substrate.

6. The spatial light modulator of claim 5, wherein the micromirror further comprises:

an extension plate connected to the mirror plate.

7. The spatial light modulator of claim 6, wherein the extension plate is extended beyond the mirror plate and connected to the mirror plate via an extension-plate post;

and wherein the extension plate defines a second gap between the extension plate and the substrate to which the hinge support is connected.

8. The spatial light modulator of claim 6, wherein the extension plate is electrically conducting.

9. The spatial light modulator of claim 6, wherein the extension plate is dielectric with a dielectric constant larger than 1.0.

10. The spatial light modulator of claim 1, wherein each micromirror further comprises:

a hinge support held by the posts on the substrate and connected to the substrate via the posts;

a hinge affixed to the hinge support; and

a mirror plate attached to the hinge such that the mirror plate rotates along a rotation axis that is parallel to but offset from a diagonal of the mirror plate when viewed from the top of the substrate.

11. The spatial light modulator of claim 10, wherein the micromirror further comprises:

a first electrode placed proximate to the mirror plate such that a first electrical filed is established between the first electrode and the mirror plate, and the mirror plate rotates relative to the substrate in a first rotation direction in response to the first electrical field.

12. The spatial light modulator of claim 11, wherein the first and the second electrode are on a substrate other than the substrate to which the hinge support is connected.

13. The spatial light modulator of claim 11, wherein the first electrode is on a substrate other than the substrate to which the hinge support is connected;

and wherein the second electrode is on the substrate to which the hinge support is connected.

14. The spatial light modulator of claim 12, wherein the second electrode is an electrode film on a surface of the substrate to which the hinge support is connected.

15. The spatial light modulator of claim 14, wherein the extension plate is connected to the mirror plate via an extension-plate post and the extension plate defines a first gap between the extension and the mirror plate.

16. The spatial light modulator of claim 10, wherein the micromirror further comprises:

a second electrode placed proximate to the mirror plate such that a second electrical field is established between the second electrode and the mirror plate, and the mirror plate rotates relative to the substrate in a second rotation direction in response to the first electrical field, wherein the second rotation direction is opposite to the first rotation direction.

17. The spatial light modulator of claim 10, wherein the micromirror further comprises:

a first stop for stopping the rotation of the mirror plate when the mirror plate rotates to an ON state angle.

18. The spatial light modulator of claim 17, wherein the first stop is disposed on the hinge support.

19. The spatial light modulator of claim 10, wherein the micromirror further comprises:

a second stop for stopping the rotation of the mirror plate when the mirror plate rotates to an OFF state.

20. The spatial light modulator of claim 19, wherein second stop is disposed on the hinge support.

21. The spatial light modulator of claim 1, wherein the substrate has an anti-reflection film on a surface of the substrate.

22. A spatial light modulator comprising:

an array of micromirrors, wherein imaginary lines connecting centers of each micromirror in the array form an imaginary grid of rows and columns orthogonal to each other, and wherein the edges of the micromirrors are not parallel to either the rows or columns in the imaginary grid, wherein the mirror plates are formed on a rectangular substrate; and

wherein each side of the micromirror is at an angle of from 5°

degrees to 25°

degrees to the two sides of the rectangular substrate.

23. The spatial light modulator of claim 22, wherein the micromirrors are rectangular or square.

24. The spatial light modulator of claim 22, wherein the substrate is in a rectangular shape;

and wherein each side of the micromirror is at an angle of from 10°

degrees to 20°

degrees to the two sides of the rectangular substrate.

25. The spatial light modulator of claim 22, wherein each micromirror further comprises:

a hinge support held by the posts on the substrate and connected to the substrate via the posts;

a hinge affixed to the hinge support; and

a mirror plate attached to the hinge such that the mirror plate rotates along a rotation axis that is parallel to but offset from a diagonal of the mirror plate when viewed from the top of the substrate.

26. The spatial light modulator of claim 25, wherein the micromirror further comprises:

a first electrode placed proximate to the mirror plate such that a first electrical filed is established between the first electrode and the mirror plate, and the mirror plate rotates relative to the substrate in a first rotation direction in response to the first electrical field; and

a second electrode placed proximate to the mirror plate such that a second electrical field is established between the second electrode and the mirror plate, and the mirror plate rotates relative to the substrate in a second rotation direction in response to the first electrical field, wherein the second rotation direction is opposite to the first rotation direction.

27. The spatial light modulator of claim 26, wherein the second electrode is an electrode film on a surface of the substrate to which the hinge support is connected.

28. The spatial light modulator of claim 26, wherein the micromirror further comprises:

an extension plate connected to the mirror plate.

29. The spatial light modulator of claim 28, wherein the extension plate is connected to the mirror plate via an extension-plate post and the extension plate defines a first gap between the extension and the mirror plate.

30. The spatial light modulator of claim 28, wherein the extension plate is extended beyond the mirror plate and connected to the mirror plate via an extension-plate post;

and wherein the extension plate defines a second gap between the extension plate and the substrate to which the hinge support is connected.

31. The spatial light modulator of claim 30, wherein the micromirror further comprises:

a first stop for stopping the rotation of the mirror plate when the mirror plate rotates to an ON state angle.

32. The spatial light modulator of claim 31, wherein the micromirror further comprises:

a second stop for stopping the rotation of the mirror plate when the mirror plate rotates to an OFF state.