Adaptive illumination modulator

• US 6,857,751 B2
• Filed: 12/20/2002
• Issued: 02/22/2005
• Est. Priority Date: 12/20/2002
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Bartlett, Terry, Penn, Steven M., Dewald, Duane S.
• Primary Examiner(s): MAHONEY, CHRISTOPHER E
• Application Number:
  US10/326,237
• Publication Number:
  US 20040119950A1
• Time in Patent Office: 795 Days
• Field of Search: 353/97, 353/88, 353/122, 359738-740
• US Class Current: 353/97
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 5/005 Diaphragms for cameras G03B9/02
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]
• CPC Class Codes: H04N 9/3114 by using a sequential colour filter producing one colour at a time
• CPC Class Codes: H04N 9/315 Modulator illumination systems general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20

Abstract

An image display system includes a light source capable of generating an illumination light beam along an illumination path. The system also includes a modulator operable to receive at least a portion of the illumination light beam and to selectively communicate at least some of the illumination light beam received by the modulator along a projection light path. The system further includes at least one adjustable illumination aperture operable to selectively control an amount of the at least a portion of the illumination light beam received by the modulator based at least in part on image data.

Claims

1. An image display system, comprising:

a light source capable of generating an illumination light beam along an illumination path;

a spatial light modulator comprised of an array of elements operable to deflect about an axis, said elements operable receive at least a portion of the illumination light beam and to communicate at least some of the illumination light beam received by the modulator along a projection light path;

at least one adjustable illumination aperture having an opening larger in a direction parallel to the axis than in a direction perpendicular to the axis and operable to selectively control an amount of the at least a portion of the illumination light beam received by the modulator; and

at least one adjustable projection aperture having an opening larger in a direction parallel to the axis than in a direction perpendicular to the axis and operable to selectively control an amount of the light communicated along the projection light path.

2. The system of claim 1, wherein the modulator comprises a device selected from a group consisting of a digital micromirror device, a reflective liquid crystal modulator, and a light emitting diode modulator.

3. The system of claim 1, wherein the at least one adjustable illumination aperture comprises a device selected from a group consisting of a translating aperture, a rotating aperture, a sliding gate aperture, and a rotating vane aperture.

4. The system of claim 1, wherein the at least one adjustable illumination aperture selectively controls the amount of the illumination beam based at least in part on image data.

5. The system of claim 4, wherein the image data comprises data selected from a group consisting of an image content of an image frame, a color content of an image frame, an integrated intensity of an image frame, a peak-to-peak intensity value of an image frame, and subjectively weighted area.

6. The system of claim 1, wherein the at least one adjustable illumination aperture selectively controls the amount of the illumination light beam based at least in part on image data and an ambient room environment.

7. The system of claim 1, further comprising:

a control module operable to generate a control signal based at least in part on an image intensity algorithm;

a feedback loop operable to communicate the image data from a processor to the control module for use in the image intensity algorithm; and

a servo-motor operable to position the at least one adjustable illumination aperture based at least in part the control signal generated by the control module.

8. The system of claim 7, wherein the image intensity algorithm is based at least in part on an ambient environment.

9. The system of claim 1, wherein the at least one adjustable projection aperture comprises a device selected from a group consisting of a translating aperture, a rotating aperture, a sliding gate aperture, and a rotating vane aperture.

10. The system of claim 1, wherein the at least one adjustable projection aperture selectively controls the amount of the illumination light beam based at least in part on image data and an ambient room environment.

11. The system of claim 10, wherein the image data comprises data selected from a group consisting of an image content of an image fame, a color content of an image frame, an integrated intensity of an image frame, a peak-to-peak intensity value of an image frame, and subjectively weighted area.

12. A method of displaying an image, comprising:

generating an illumination light beam along an illumination path;

receiving at least a portion of the illumination light beam at a spatial light modulator;

selectively communicating at least some of the illumination light beam received by the modulator along a projection light path using an array of elements operable to rotate about an axis;

selectively controlling an amount of the illumination light beam communicated along said projection light path using at least one illumination aperture having an opening larger in a direction parallel to the axis than in a direction perpendicular to the axis and at least one projection aperture having an opening larger in a direction parallel to the axis than in a direction perpendicular to the axis;

wherein the selectively controlling step is in response to data from a group consisting of image data and an ambient room environment.

13. The method of claim 12, wherein the selectively controlling step is performed at least on a frame-by-frame basis of display data.

14. The method of claim 12, wherein the selectively controlling step is performed at a modulation rate faster than a modulation rate of the spatial light modulator.

15. The method of claim 12, wherein the selectively controlling step to selectively vary an intensity of the illumination light beam, while substantially maintaining a constant contrast ratio.

16. The method of claim 12, wherein the image data comprises data selected from a group consisting of an image content of an image frame, a color content of an image frame, an integrated intensity of an image frame, a peak-to-peak intensity value of an image frame, and subjectively weighted area.

17. The method of claim 12, wherein the selectively controlling step is performed by changing the size of an opening created by at least one said at least one aperture.

18. The method of claim 12, wherein the selectively controlling step is performed by rotating at least one said at least one aperture relative to a cone of light.