SYSTEM AND METHOD OF ILLUMINATING INTERFEROMETRIC MODULATORS USING BACKLIGHTING

• US 20090225394A1
• Filed: 02/25/2008
• Published: 09/10/2009
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Chui, Clarence, Tung, Ming-Hau
• Granted Patent: US 8,040,588 B2
• Time in Patent Office: Days
• US Class Current: 359/290
• 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
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3466 based on interferometric effect
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]
• CPC Class Codes: H04W 52/027 by controlling a display operation or backlight unit
• CPC Class Codes: Y02D 30/70 in wireless communication networks
• CPC Class Codes: Y10S 359/90 Methods

Abstract

An interferometric modulator array device with backlighting is disclosed. The interferometric modulator array device comprises a plurality of interferometric modulator elements, wherein each of the interferometric modulator elements comprises an optical cavity. The interferometric modulator array includes an optical aperture region, and at least one reflecting element is positioned so as to receive light passing through the optical aperture region and reflect at least a portion of the received light to the cavities of the interferometric modulator elements. In some embodiments, the interferometric modulator elements may be separated from each other such that an optical aperture region is formed between adjacent interferometric modulator elements.

Claims

1. A light-modulating array comprising:

a first light-modulating element comprising a first reflective surface disposed on a substrate and a second reflective surface spaced from the first reflective surface of the first light-modulating element;

a second light-modulating element comprising a first reflective surface disposed on the substrate and a second reflective surface spaced from the first reflective surface of the second light-modulating element;

a light source disposed on a side of the first and second light-modulating elements opposite to a side from which the light-modulating array is configured to be viewed;

an optical aperture region between the first light-modulating element and the second light-modulating element, light propagating from the light source configured to pass through the optical aperture region; and

a reflecting element configured to reflect at least a portion of the passed light towards at least one of the first and second light-modulating elements.

2. The light-modulating array of claim 1, wherein the light source is uncollimated.

3. The light-modulating array of claim 2, wherein a width of the reflecting element is greater than a width of the optical aperture region.

4. The light-modulating array of claim 2, wherein a width of the reflecting element is at least about three times greater than a width of the optical aperture region.

5. The light-modulating array of claim 2, wherein a width of the reflecting element extends beyond each side of the optical aperture region by a width of the optical aperture region.

6. The light-modulating array of claim 2, further comprising a collimating optic between the light source and the reflecting element.

7. The light-modulating array of claim 6, wherein the collimating optic comprises a lens.

8. The light-modulating array of claim 6, wherein a width of the reflecting element is no greater than a width of the optical aperture region.

9. The light-modulating array of claim 2, further comprising an optical film between the light source and the reflecting element, the optical film configured to eliminate light propagating from the light source at extreme angles.

10. The light-modulating array of claim 9, wherein the optical film comprises a filter.

11. The light-modulating array of claim 9, wherein a width of the reflecting element is no greater than a width of the optical aperture region.

12. The light-modulating array of claim 1, wherein the light source is collimated.

13. The light-modulating array of claim 12, wherein a width of the reflecting element is no greater than a width of the optical aperture region.

14. The light-modulating array of claim 1, wherein the reflecting element has a width between about 1 μ

m and about 10 μ

m.

15. The light-modulating array of claim 1, wherein the reflecting element has a height between about 200 Å

and about 1000 Å

.

16. The light-modulating array of claim 1, wherein the reflecting element is configured to reflect at least a portion of the passed light towards both the first and second light-modulating elements.

17. The light-modulating array of claim 1, further comprising at least one additional reflecting element, each of the reflecting elements configured to reflect at least a portion of the passed light towards at least one of the first and second light-modulating elements.

18. The light-modulating array of claim 17, wherein each of the reflecting elements configured to reflect at least a portion of the passed light towards one of the first and second light-modulating elements.

19. The light-modulating array of claim 1, wherein the first and second modulating elements comprise spatial light modulators.

20. The light-modulating array of claim 1, wherein the first and second modulating elements comprise interferometric modulators.