Projector/camera system

• US 20080094588A1
• Filed: 10/06/2006
• Published: 04/24/2008
• Est. Priority Date: 10/06/2006
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Mandigo, Lonnie D., Cole, James R., Bronstein, Kenneth H.
• Granted Patent: US 7,690,795 B2
• Time in Patent Office: Days
• US Class Current: 353/122
• CPC Class Codes: G03B 17/48 adapted for combination with other photographic or optical apparatus
• CPC Class Codes: G03B 21/00 Projectors or projection-type viewers; Accessories therefor devices for changing pictures G03B23/00

Abstract

A projector/camera system includes a projector, configured to project a sequenced image to a projection location, and a camera, located at the projection location and oriented to take an image of a region including the projector. The camera is configured to capture a sequenced image that is synchronized and out of phase with the sequenced image of the projector, thereby to minimize light interference from the projector.

Claims

1. A projector/camera system, comprising:

a projector, configured to project a sequenced image to a projection location; and

a camera, located at the projection location and oriented to take an image of a region including the projector, the camera being configured to capture a sequenced image that is synchronized and out of phase with the sequenced image of the projector, thereby to minimize light interference from the projector.

2. A system in accordance with claim 1, wherein the camera and projector are chromatically out of phase.

3. A system in accordance with claim 2, wherein the camera and projector each include a rotating color wheel having corresponding color filter segments, the rotation of the color wheel of the projector being synchronized and out of phase with the rotation of the color wheel of the camera.

4. A system in accordance with claim 3, wherein the color wheels in the camera and projector each include red, green, and blue filter segments

5. A system in accordance with claim 3, wherein the color wheel in the projector includes red, green, blue and white filter segments, and the color wheel in the camera includes red, green, blue and black filter segments.

6. A system in accordance with claim 1, wherein the camera and projector are out of phase in a manner selected from the group consisting of temporally out of phase and spatially out of phase.

7. A system in accordance with claim 1, wherein the projection location comprises a transparent or semi-transparent front projection screen, the projector being located in front of the screen, and the camera being located behind the screen.

8. A system in accordance with claim 1, wherein the projection location comprises a transparent or semi-transparent rear projection screen, and the projector and camera are both located behind the screen.

9. A system in accordance with claim 1, further comprising:

a remote projector, configured to receive an image signal from the camera, and to project an image based upon the image signal to a remote projection location; and

a remote camera, configured to provide an image to the projector.

10. A system in accordance with claim 9, wherein the remote projector is configured to project a sequenced image to the remote projection location, and the remote camera is oriented to take an image of a region including the remote projector, the remote camera being configured to capture and provide a sequenced image that is out of phase with the sequenced image of the remote projector, thereby to minimize light interference from the remote projector.

11. A video conferencing system, comprising:

a first projector, configured to project a sequenced image to a first projection location;

a first camera, located at the first projection location and oriented to take an image of a region including the projector, the camera being configured to capture a sequenced image that is synchronized and out of phase with the sequenced image of the projector, thereby to minimize light interference from the projector;

a second projector, configured to receive an image signal from the first camera, and to project an image based upon the image signal to a second projection location; and

a second camera, configured to provide an image to the first projector.

12. A video conferencing system in accordance with claim 11, wherein the first camera and first projector are out of phase in a manner selected from the group consisting of chromatically out of phase, temporally out of phase, and spatially out of phase.

13. A video conferencing system in accordance with claim 12, wherein the first camera and first projector are chromatically out of phase and each include a rotating color wheel having corresponding color filter segments, the rotation of the color wheel of the first projector being synchronized and out of phase with the rotation of the color wheel of the first camera.

14. A video conferencing system in accordance with claim 11, wherein the second projector is configured to project a sequenced image to the second projection location, and the second camera is oriented to take an image of a region including the second projector, the second camera being configured to capture and provide a sequenced image that is synchronized and out of phase with the sequenced image of the second projector, thereby to minimize light interference from the second projector.

15. A video conferencing system in accordance with claim 11, wherein the first projection location comprises a transparent or semi-transparent front projection screen, the first projector being located in front of the screen, and the first camera being located behind the screen.

16. A method for reducing light interference in a system having a projector, configured to project an image to a projection location, and a camera, located at the projection location and oriented to take an image of a region including the projector, comprising the steps of:

projecting a sequenced image with the projector; and

capturing a sequenced image with the camera, the sequenced image of the camera being synchronized and out of phase with the sequenced image of the projector, such that light interference from the projector to the camera is reduced.

17. A method in accordance with claim 16, wherein the sequenced image is captured by the camera is out of phase with the projector in a manner selected from the group consisting of chromatically out of phase, temporally out of phase, and spatially out of phase.

18. A method in accordance with claim 16, wherein the step of projecting a sequenced image with the projector comprises projecting a series of component images through a series of color filter segments of a rotating projector color wheel, and the step of capturing a sequenced image with the camera comprises capturing a series of component images through a series of color filter segments of a rotating camera color wheel, and further comprising the step of

synchronizing the rotation of the projector color wheel and the camera color wheel so that the color wheels rotate at a common frequency and out of phase, such that light projected by the projector is substantially not detected by the camera.

19. A method in accordance with claim 16, further comprising the steps of:

transmitting a camera image signal from the camera to a remote projector at a remote projection location; and

receiving a projector image signal from the remote projection location, and causing the projector to project an image based upon the projector image signal.

20. A method in accordance with claim 16, further comprising the step of placing the camera behind a transparent or semi-transparent front projection screen toward which the projector is oriented.