METHOD AND POST STRUCTURES FOR INTERFEROMETRIC MODULATION

• US 20080180777A1
• Filed: 02/25/2008
• Published: 07/31/2008
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Tung, Ming-Hau, Sethuraman, Srinivasan
• Granted Patent: US 7,719,747 B2
• Time in Patent Office: Days
• US Class Current: 359/224
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26

Abstract

An interferometric modulator includes a post structure comprising an optical element. In a preferred embodiment, the optical element in the post structure is a reflective element, e.g., a mirror. In another embodiment, the optical element in the post structure is an etalon, e.g., a dark etalon. The optical element in the post structure may decrease the amount of light that would otherwise be retroreflected from the post structure. In various embodiments, the optical element in the post structure increases the brightness of the interferometric modulator by redirecting light into the interferometric cavity. For example, in certain embodiments, the optical element in the post structure increases the backlighting of the interferometric modulator.

Claims

1. An interferometric modulator comprising:

a substrate;

a first reflective surface over the substrate, the first reflective surface being at least partially reflective and at least partially transparent to light;

a second reflective surface over the first reflective surface, the second reflective surface movable with respect to the first reflective surface; and

a support structure configured to at least partially support the second reflective surface, the support structure comprising an optical element.

2. The interferometric modulator of claim 1, wherein the optical element comprises a lens.

3. The interferometric modulator of claim 2, wherein surfaces of the lens are spherical.

4. The interferometric modulator of claim 2, wherein surfaces of the lens are parabolic.

5. The interferometric modulator of claim 2, wherein surfaces of the lens are concave.

6. The interferometric modulator of claim 2, wherein surfaces of the lens are convex.

7. The interferometric modulator of claim 1, wherein the optical element comprises a prism.

8. The interferometric modulator of claim 7, wherein surfaces of the prism are inclined with respect to the post structure.

9. The interferometric modulator of claim 7, wherein surfaces of the prism are declined with respect to the post structure.

10. The interferometric modulator of claim 1, wherein surfaces of the optical element are symmetrical.

11. The interferometric modulator of claim 1, wherein surfaces of the optical element are asymmetrical.

12. The interferometric modulator of claim 1, wherein surfaces of the optical element are smooth.

13. The interferometric modulator of claim 1, wherein surfaces of the optical element are rough.

14. The interferometric modulator of claim 1, wherein the optical element is configured to specularly reflect light.

15. The interferometric modulator of claim 1, wherein the optical element is configured to diffusely reflect light.

16. The interferometric modulator of claim 1, wherein the optical element is disposed off-center from the post structure.

17. An interferometric modulator array comprising:

a first reflective surface over a substrate;

a plurality of second reflective surfaces over the first reflective surface, each of the second reflective surfaces movable with respect to the first reflective surface; and

a plurality of support structures configured to at least partially support the second reflective surfaces, wherein at least some of the plurality of support structures comprise an optical element.

18. The interferometric modulator array of claim 17, wherein some of the optical elements are different from others of the optical elements.

19. The interferometric modulator array of claim 18, wherein a height of the some of the optical elements are different from a height of the other of the optical elements.

20. The interferometric modulator array of claim 17, wherein some of the optical elements comprise an etalon.