SYSTEMS AND METHODS USING INTERFEROMETRIC OPTICAL MODULATORS AND DIFFUSERS

• US 20100165443A1
• Filed: 10/28/2009
• Published: 07/01/2010
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Chui, Clarence
• Granted Patent: US 7,944,602 B2
• Time in Patent Office: Days
• US Class Current: 359/291
• 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: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

Various embodiments include interferometric optical modulators comprising a substrate layer having a thickness between about 0.1 mm to about 0.45 mm thick and a method for manufacturing the same. The interferometric modulator can be integrated together with a diffuser in a display device. The thin substrate permits use of a thicker diffuser. The thinner substrate may increase resolution and reduce overall thickness of the inteferometric modulator. The thicker diffuser may provide increased diffusion and durability.

Claims

1. A spatial light modulator comprising:

a substrate having a first side and a second side;

a plurality of pixels disposed on the first side of the substrate, the plurality of pixels spaced on the first side of the substrate with a pitch, each of the plurality of pixels comprising an interferometric light modulator configured to be individually actuated to modulate light in response to an electrical signal; and

a diffuser disposed on the second side of the substrate,

wherein the substrate has a thickness between the first side and the second side that is less than approximately the pitch of the plurality of pixels.

2. The spatial light modulator of claim 1, wherein the thickness of the substrate is such that the spatial light modulator achieves a contrast greater than about 5 to 1 for a displayed test pattern of alternating white and black lines having a spatial period of approximately the pitch of the plurality of pixels.

3. The spatial light modulator of claim 1, wherein the thickness of the substrate is sufficiently small that light incident on a first portion of the diffuser disposed over a first pixel of the plurality of pixels is not scattered into a second pixel of the plurality of pixels, the second pixel adjacent the first pixel.

4. A method of forming a spatial light modulator, the method comprising:

forming a plurality of interferometric light modulating elements having a spatial pitch;

forming a diffuser spaced apart from the plurality of interferometric light modulating elements by less than approximately the spatial pitch; and

patterning electrodes configured to allow individual electrical actuation of the interferometric light modulating elements.

5. The method of claim 4, wherein forming the plurality of interferometric light modulating elements comprises forming the plurality of interferometric light modulating elements on a first side of a substantially transparent substrate and forming the diffuser comprises forming the diffuser on a second side of the substantially transparent substrate.