Spatial light modulator with perforated hinge

• US 20070019278A1
• Filed: 07/19/2006
• Published: 01/25/2007
• Est. Priority Date: 07/25/2005
• Status: Active Grant

• Current Assignee: Jonathan Mohn
• Original Assignee: Jonathan Mohn
• Inventors: Mohn, Jonathan
• Granted Patent: US 7,355,781 B2
• Time in Patent Office: Days
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A spatial light modulator (SLM) is disclosed that increases speed and efficiency of an SLM through the use of a perforated hinge. The hinge may take many forms, but generally includes an elongated body having holes therein along its longitudinal direction. One or more electrodes are charged with a predetermined voltage in order rotate a reflecting surface towards the electrodes through electrostatic attraction. The perforations within the hinge results in the hinge being made from less material so that it is less sensitive to hinge thickness variations that can occur during the manufacturing process. Consequently, the perforated hinge allows for more stable, uniform mirror rotation.

Claims

1. A spatial light modulator, comprising:

a reflecting surface;

one or more electrodes; and

a perforated hinge coupled to the reflecting surface to allow rotation of the reflecting surface towards at least one of the electrodes.

2. The spatial light modulator of claim 1, wherein the perforated hinge includes an elongated body having holes therein.

3. The spatial light modulator of claim 2, wherein the holes are at least 10% of a width of the elongated body.

4. The spatial light modulator of claim 2, wherein the holes are a geometric shape including one or more of the following:

parallelograms, hexagons, squares, circles, or rectangles.

5. The spatial light modulator of claim 1, further comprising:

a spatial light modulator body having the one or more electrodes and opposing supports mounted thereto, the perforated hinge mounted to the opposing supports.

6. The spatial light modulator of claim 1, further including one or more spring fingers positioned between the surface and the electrodes to prevent contact there between.

7. The spatial light modulator of claim 1, wherein the one or more electrodes are single level or double level.

8. The spatial light modulator of claim 1, wherein the perforated hinge includes at lest two, spaced-apart longitudinal members parallel to the axis of rotation of the reflecting surface.

9. The spatial light modulator of claim 1, wherein the perforated hinge includes at least three, spaced-apart, longitudinal members parallel to the axis of rotation of the reflecting surface.

10. The spatial light modulator of claim 8 including at least one cross member positioned between the longitudinal members.

11. The spatial light modulator of claim 1, wherein the perforated hinge includes two longitudinal sidewalls with two or more geometrical perforations positioned between the sidewalls.

12. The spatial light modulator of claim 1, wherein the perforated hinge includes two, equal-length longitudinal sidewalls forming a width there between of the perforated hinge, wherein the width of the hinge varies along its length.

13. The spatial light modulator of claim 1, wherein the perforated hinge is made of material whose fatigue lifetime exceeds 1.0e⁹ hinge deflection cycles.

14. The spatial light modulator of claim 13, wherein the material includes one of the following or a combination thereof:

copper, copper alloy, aluminum, aluminium alloy, single crystal silicon, amorphous silicon, polysilicon, silicon nitride, titanium, and titanium alloy.

15. The spatial light modulator of claim 1, wherein the perforated hinge is mounted to the reflecting surface along an edge of the reflecting surface or below the reflecting surface.

16. The spatial light modulator of claim 1, wherein the reflecting surface is mounted to the perforated hinge using one or more support posts.

17. A spatial light modulator comprising:

a perforated hinge including a body having a length (L) and a width (W), the body having two side walls defining the width with at least two holes positioned therein between the two side walls;

at least one support post coupled to the perforated hinge; and

a reflecting surface mounted on the support post.

18. The spatial light modulator of claim 17 wherein the holes have a width greater than 10% the width of the body.

19. The spatial light modulator of claim 17, wherein the spatial light modulator is included in an array of spatial light modulators within a display.

20. A spatial light modulator, comprising:

a perforated hinge member having an elongated body with geometrically-shaped holes extending through the elongated body; and

a reflecting surface coupled to the perforated hinge.