Micromirror array device and a method for making the same
View Patent ↗The spatial light modulator of the present invention comprises an array of micromirrors, each of which has a reflective deflectable mirror plate. A set of posts are provided for holding the mirror plates on a substrate, but not all micromirrors of the micromirror array have posts.
1. A device comprising:
a substrate;
an array of reflective mirror plates held on the substrate, each of which is attached to a deformable hinge that is connected to a hinge support, wherein the hinge supports in the array are interconnected in first and second directions in a grid parallel to the substrate; and
an array of electrodes for addressing and electrostatically deflecting the mirror plates.
2. The device of claim 1 , wherein the first and second directions are perpendicular to each other.
3. The device of claim 1 , wherein the first and second directions are not perpendicular to each other.
4. The device of claim 1 , wherein the first or second direction is parallel to an edge of the mirror plate array.
5. The device of claim 1 , wherein the first direction is parallel to an edge of the mirror plate array; and the second direction is parallel to another edge of the mirror plate array.
6. The device of claim 1 , wherein the hinge supports are connected into a hinge support frame.
7. The device of claim 1 , wherein only a portion of the hinge supports are interconnected.
8. The device of claim 1 , wherein all of the hinge supports are interconnected.
9. The device of claim 1 , further comprising a number of posts that connect the hinge supports to the substrate, wherein at least one of the hinge support is not directly connected to one of the number of posts.
10. The device of claim 1 , further comprising a number of posts that connect the hinge supports to the substrate, wherein a ratio of the total number of posts and total number N of mirror plates in the array is less than (N+1)/N.
11. The device of claim 1 , wherein the deformable hinges and reflective mirror plates are in separate planes parallel to the substrate.
12. The device of claim 1 , wherein the interconnected hinge supports and reflective mirror plates are in separate planes parallel to the substrate.
13. The device of claim 1 , wherein the mirror plate is attached to the deformable hinge at an attachment point that is substantially away from the center of the mirror plate such that the mirror plate is capable of rotating asymmetrically.
14. The device of claim 1 , wherein the mirror plate is attached to the deformable hinge at an attachment point that is substantially at the center of the mirror plate such that the mirror plate is capable of rotating symmetrically.
15. The device of claim 1 , wherein the substrate is transmissive to visible light.
16. The device of claim 15 , wherein the substrate is glass, quartz, or sapphire.
17. The device of claim 15 , wherein the substrate is glass.
18. The device of claim 17 , wherein the electrode is formed on a semiconductor substrate.
19. The device of claim 1 , wherein the substrate is a semiconductor substrate on which the electrode is formed.
20. A projection system, comprising:
an illumination system providing illumination light;
a spatial light modulator comprising the device of claim 1 for modulating the illumination light; and
a projection lens for projecting the modulated light onto a screen.
21. The projection system of claim 20 , wherein the illumination system comprises an arc lamp, a lightpipe, and a color wheel.
22. The projection system of claim 21 , wherein the color wheel is positioned between the arc lamp and the lightpipe along a propagation path of the illumination light.
23. The projection system of claim 21 , wherein the color wheel is positioned after the arc lamp and the lightpipe along a propagation path of the illumination light.