Method and apparatus for increasing microdisplay black state in light management systems and flexibility to utilize polarized or unpolarized input light

• US 20040008418A1
• Filed: 03/05/2003
• Published: 01/15/2004
• Est. Priority Date: 03/05/2002
• Status: Active Grant

• Current Assignee: Lightmaster Systems Incorporated
• Original Assignee: Lightmaster Systems Incorporated
• Inventors: Berman, Arthur
• Granted Patent: US 7,280,281 B2
• Time in Patent Office: Days
• US Class Current: 359/634
• CPC Class Codes: G02B 27/1013 for colour or multispectral image sensors, e.g. splitting an image into monochromatic image components on respective sensors spectral imaging systems G01J
• CPC Class Codes: G02B 27/1026 for use with reflective spatial light modulators
• CPC Class Codes: G02B 27/145 having sequential partially reflecting surfaces
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 2203/02 reflective
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 3/002 to project the image of a two-dimensional display, such as an array of light emitting or modulating elements or a CRT
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/3167 for polarizing the light beam polarizing optical systems per se G02B27/28
• CPC Class Codes: H04N 9/3191 Testing thereof testing of displays in general G09G3/006

Abstract

A dichroic is positioned to separate color beams of polarized input light. The color beams are directed to microdisplays that contain correspondingly colored content in a kernel of a Light Management System (LMS). Adjustment of a voltage amplitude of the microdisplays is set to produce a maximum black state of the LMS. In one embodiment, a passive nematic liquid crystal device is utilized as a quarter waveplate. A thickness of a liquid crystal layer (d) is matched to a birefringence (Δn) of the nematic such that retardation dΔn=¼λ.

Claims

1. A kernel, comprising:

an input face configured to receive input polarized light;

a beam separating dichroic arranged on a diagonal to the input polarized light and configured to separate the input polarized light into a first color beam and a second color beam.

2. The kernel according to claim 1, wherein the beam separating dichroic is configured to reflect the first color beam and pass the second color beam.

3. The kernel according to claim 1, wherein the beam separating dichroic is sensitive to S polarized light.

4. The kernel according to claim 1, wherein the beam separating dichroic is sensitive to P polarized light.

5. The kernel according to claim 1, wherein the first color beam is green, and the second color beam is red and blue.

6. The kernel according to claim 1, wherein the first color beam is red, and the second color beam is green and blue.

7. The kernel according to claim 1, wherein the first color beam is blue, and the second color beam is red and green.

8. The kernel according to claim 1, wherein the kernel is a quad style kernel.

9. The kernel according to claim 1, wherein the kernel is a style other than a quad style kernel.

10. A quality control method, comprising the steps of:

producing a display device having at least one microdisplay; and

setting a voltage amplitude on a microdisplay to produce a highest black state of the display device.

11. The quality control method according to claim 10, wherein the display device comprises multiple microdisplays;

and

said step of setting comprises individually setting a voltage amplitude on each microdisplay to produce a highest possible black sate of the display.

12. The quality control method according to claim 10, wherein:

said at least one microdisplay

said step of producing comprises producing a display device having a set of channels each comprising a light path for a specific band of light interacting with a microdisplay device having a waveplate that compensates

13. The quality control method according to claim 10, wherein:

said display device comprises a kernel, comprising,

an input face configured to receive input polarized light, and

a beam separating dichroic arranged on a diagonal to the input polarized light and configured to separate the input polarized light into a first color beam and a second color beam.