Anti-reflective coatings for spatial light modulators

• US 6,282,010 B1
• Filed: 05/06/1999
• Issued: 08/28/2001
• Est. Priority Date: 05/14/1998
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Trombley, Henry W., Sulzbach, Frank C., Huang, Austin L., Ray, Brian L., Sreenivas, G., Huffman, James D., Carter, Duane E.
• Primary Examiner(s): MAI, HUY KIM
• Application Number:
  US09/306,271
• Time in Patent Office: 845 Days
• Field of Search: 359/290, 359/291, 359/292, 359/297, 359/245, 359/247, 359/248, 359/249, 359/321, 349/137
• US Class Current: 359/249
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers

Abstract

A spatial light modulator with an anti-reflective coating (ARC) 100 integrated into its structure. The manufacturing of the device is altered to include deposition of an ARC 100, and any necessary patterning and etching to allow the elements of the array to operate properly. The ARC could reside in several places of the element structure including over the addressing circuitry 26, over a middle layer 32 or on the underside of the reflective structure 10. Micromechanical spatial light modulators, as well as non-moving modulators, such as reflective and transmissive LCD modulators can use the invention.

Claims

1. A spatial light modulator having an array of individually addressable elements, each said element comprising:

an active component selectively operable to reflect light from a reflective surface to an imaging system when activated;

addressing circuitry to activate said active component;

an anti-reflective coating placed to prevent light not reaching said reflective surface from entering said imaging system.

2. The spatial light modulator of claim 1, wherein said anti-reflective coating is placed over said addressing circuitry.

3. The spatial light modulator of claim 1, said active component having an underside surface opposite said reflective surface, wherein said anti-reflective coating is placed on said underside surface of said active component.

4. The spatial light modulator of claim 1, wherein said element further comprises a middle layer of said element, and said middle layer has an anti-reflective coating.

5. The spatial light modulator of claim 1, wherein said anti-reflective coating comprises TiN.

6. The spatial light modulator of claim 5, wherein said anti-reflective coating further comprises SiO₂.

7. The spatial light modulator of claim 1, wherein said anti-reflective coating is comprised of diamond-like carbon.

8. The spatial light modulator of claim 1, wherein said anti-reflective coating is comprised of dark resin.

9. A method of manufacturing a spatial light modulator having an array of individually addressable elements, said method including the steps of:

forming addressing circuitry on a substrate;

providing an array of active components on said addressing circuitry, said active components comprising a reflective surface, wherein said addressing circuitry activates said active components to cause said reflective surfaces to reflect light to an imaging system; and

wherein at least one of said forming and providing steps includes the step of depositing an anti-reflective coating positioned to prevent light not reaching said reflective surface from entering said imaging system.

10. The method of claim 9, wherein said method further comprises the steps of:

building an intermediate structure on said addressing circuitry, upon which said active components reside, wherein said intermediate structure has an anti-reflective coating.

11. The method of claim 9 wherein said anti-reflective coating is comprised of TiN.

12. The method of claim 11 wherein said anti-reflective coating further comprises a layer of SiO₂.

13. The method of claim 9 wherein said anti-reflective coating is comprised of diamond-like carbon.

14. The method of claim 9 wherein said anti-reflective coating is comprised of dark resin.