Tir light valve

• US 20090116099A1
• Filed: 01/02/2009
• Published: 05/07/2009
• Est. Priority Date: 12/09/2005
• Status: Active Grant

• Current Assignee: Rambus Delaware LLC (Rambus Inc.)
• Original Assignee: Rambus International Ltd (Rambus Inc.)
• Inventors: Richardson, Brian Edward
• Granted Patent: US 7,808,697 B2
• Time in Patent Office: Days
• US Class Current: 359/320
• CPC Class Codes: G02B 26/0875 by means of one or more refracting elements
• CPC Class Codes: G02B 26/0883 the refracting element being a prism

Abstract

An array of light valves switch light by enabling and disabling total internal reflection (TIR) on a surface of the light valve. The disabling of the TIR is accomplished by putting another optical element in contact with the surface and then diffusing or changing the direction of the light. The mechanical mechanism to move the optical element is a simple one in that it only moves the optical element a small distance to change the valve from a first position to a second position.

Claims

1. A light valve comprising:

an array of functionally equivalent light valves, each said light valve comprising;

a means for bending light, said means for bending light having an index of refraction much greater than an index of refraction of a surrounding area, so that light projected onto a first surface of said means for bending light is reflected off a second surface of said means for bending light,

a switching element comprising a reflecting surface, and

a means for moving said reflecting surface of said switching element relative to said second surface of said means for bending light;

wherein

when said switching means is in a first position, light passing through said first surface of said means for bending light reflects off of said second surface of said means for bending light and passes through an output surface of said means for bending light, and

when said switching means is in a second position, said reflecting surface is moved to a position touching or in close proximity to said second surface of said means for bending light, so that light passing through said first surface of said means for bending light is not reflected off said second surface, but rather continues on to a surface of said switching means, and

said switching means redirects the light in a direction not substantially parallel to a direction of said light passing through said first surface of said means for bending light.

2. The light valve of claim 1 wherein:

light is reflected off a serrated surface of each said switch element when said switch array is in said second position.

3. The light valve of claim 1 wherein:

light is absorbed by said switch elements comprising said array when said switch array is in said second position.

4. The light valve of claim 1 wherein:

light is diffused by each said switch element when said switch array is in said second position.

5. The light valve of claim 1 wherein:

at least one of said switch elements has a diffuse topography.

6. The light valve of claim 1 wherein:

said means for bending light is a prism.

7. The light valve of claim 1 wherein:

at least one surface of said means for bending light is coated with an elastic material.

8. The light valve of claim 1 wherein:

at least one surface of said switching means is coated with an elastic material.

9. The light valve of claim 1 wherein:

at least one of said switching means is moved between said first position and said second position by an electrostatic force.

10. The light valve of claim 1 wherein:

at least one of said switching means is moved between said first position and said second position by a spring force.