Methods and apparatus for spatial light modulation

• US 7,742,215 B2
• Filed: 10/30/2007
• Issued: 06/22/2010
• Est. Priority Date: 02/23/2005
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Hagood, Nesbitt W. IV
• Primary Examiner(s): Choi; William C
• Application Number:
  US11/981,168
• Publication Number:
  US 20080062500A1
• Time in Patent Office: 966 Days
• Field of Search: 359/198, 359/214, 359/224, 359/290, 359/295, 359/198.1, 359/199.2, 359/199.4, 359/200.6, 359/200.8, 359/224.1, 359/230, 359/233
• US Class Current: 359/233
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0078 Side-by-side arrangements, e.g. for large area displays

Abstract

The invention relates to methods and apparatus for forming images on a display utilizing a control matrix to control the movement of MEMs-based light modulators.

Claims

1. A projection display comprising:

a transparent substrate;

a plurality of shutter-based MEMS light modulators disposed on a surface of the transparent substrate, wherein the shutter-based light modulators each include an actuator for driving a shutter, wherein the actuators include first and second compliant beams, which, in response to application of a voltage across the first and second compliant beams, deform towards one another; and

projection optics for projecting light modulated by the shutter-based MEMS light modulators onto a display surface to form an image.

2. The projection display of claim 1, wherein the first compliant beam is free at one end to move towards the second compliant beam in response to the application of the voltage.

3. The projection display of claim 1, wherein the second beam is coupled to the shutter and the transparent substrate.

4. The projection display of claim 1, wherein the first compliant beam has a dimension parallel to the surface of the transparent substrate that is less than about 2.0 microns.

5. The projection display of claim 1, comprising a color wheel for generating a sequence of colors of light for modulation by the shutter-based MEMS light modulators.

6. The projection display of claim 1, wherein the first and second compliant beams are compliant in a direction parallel to the surface of the transparent substrate and are substantially rigid in a direction normal to the transparent substrate.

7. A projection display comprising:

a transparent substrate;

a plurality of shutter-based MEMS light modulators disposed on a surface of the transparent substrate, wherein one of the shutter-based light modulators includes a shutter configured for motion limited substantially to a plane that is parallel to the surface of transparent substrate, wherein the shutter includes mechanical supports coupled to the shutter for limiting motion of the shutter in a direction normal to the plane of the surface of the transparent substrate and at least one of the mechanical supports is anchored to the transparent substrate in at least two locations to reduce rotational movement of the shutter; and

projection optics for projecting light modulated by the shutter-based MEMS light modulators onto a display surface to form an image.