Integrated front projection system with shaped imager and associated method

• US 20020021417A1
• Filed: 05/01/2001
• Published: 02/21/2002
• Est. Priority Date: 03/03/1999
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: DeLuca, Patricia H., Rodriguez, Ernesto M. Jr., Carls, Joseph C.
• Granted Patent: US 6,568,814 B2
• Time in Patent Office: Days
• US Class Current: 353/69
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• CPC Class Codes: G03B 21/147 Optical correction of image distortions, e.g. keystone
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14

Abstract

A front image projection device and corresponding method are disclosed that utilize a shaped imager component to pre-distort an input image and thereby compensate for the distortion expected in a screen image. The front projection device includes projection components, image generating components, and illumination components. The shaped image component may compensate at least in part for distortion introduced due to the components of the projection system. The physical configuration for the shaped imager may be determined through a modeled or actual ray trace through the projection system, and the resulting physical configuration may be a geometric shape having a curved top, a curved bottom and curved sides.

Claims

1. A front image projection device, comprising:

projection components operable to project an input image onto a projection screen to produce a screen image;

illumination components coupled to the projection components; and

image generating components operable to generate the input image, the image generating components comprising a shaped imager component physically configured to pre-distort the input image to compensate at least in part for distortion in the displayed screen image, the physical configuration being determined at least in part from a ray trace.

2. The front image projection device of claim 1, wherein the ray trace comprises an actual ray trace through the projection device.

3. The front image projection device of claim 1, wherein the ray trace comprises a modeled ray trace through the projection device.

4. The front image projection device of claim 1, wherein the projection screen is coupled to and integrated with the projection device.

5. The front image projection device of claim 1, wherein the projection components comprise off-axis optics, and wherein a throw-to-screen diagonal ratio is at most 1.

6. The front image projection device of claim 1, wherein the projection components produce optical and geometric distortion in the screen image with respect to the input image.

7. The front image projection device of claim 6, wherein the shaped imager component has a geometric shape configured to compensate for the optical and geometric distortion of the projection components.

8. The front projection system of claim 7, wherein the geometric shape comprises a curved top, a curved bottom and curved sides.

9. The front projection system of claim 8, wherein the shaped imager component has a plurality of rows of pixels.

10. The front image projection system of claim 9, wherein the number of pixels per row are the same and wherein the spacing between each pixel within a given row is different for different rows of pixels.

11. An integrated front image projection system, comprising:

a front projection screen;

a movable arm coupled to the front projection screen, the arm having a storage position and a projection position;

a front projection head coupled to the arm distal the front projection screen;

projection components housed within the front projection head, the projection components operable to project an input image onto a projection screen thereby displaying a screen image;

illumination components coupled to the projection components; and

image generating components operable to generate the input image, the image generating components comprising a shaped imager component physically configured to pre-distort the input image to compensate at least in part for distortion in the displayed screen image, the physical configuration comprising a geometric shape having a curved top, a curved bottom and curved sides.

12. The integrated front image projection system of claim 11, wherein the geometric shape is determined at least in part from a ray trace.

13. The integrated front projection system of claim 11, wherein the projection components comprise off-axis optics, and wherein a throw-to-screen diagonal ratio of at most 1.

14. The integrated front projection system of claim 11, wherein the projection components produce optical and geometric distortion in the screen image with respect to the input image.

16. The method of claim 15, further comprising determining the geometric shape at least in part from a ray trace.

17. The method of claim 15, further comprising projecting the input image with the front projection device to form a screen image that has distortion corrected by the shaped imager.

18. The method of claim 17, wherein the projecting is accomplished using projection components that comprise off-axis optics, and wherein a throw-to-screen diagonal ratio of at most 1.

19. The method of claim 15, wherein the distortion is optical and geometric distortion in the screen image with respect to the input image.

20. The method of claim 15, wherein the shaped imager component comprises a plurality of rows of pixels.

21. The method of claim 20, wherein the number of pixels in each row is constant and wherein the spacing between each pixel in a given row is different for different rows of pixels.

15. A method for projecting a corrected screen image with a front projection device, comprising:

providing a front projection device configured to project an input image onto a projection screen thereby displaying a screen image; and

compensating for distortion in the screen image caused by components of the front projection device at least in part by utilizing a shaped imager component physically configured to pre-distort an input image, the physical configuration comprising a geometric shape having a curved top, a curved bottom and curved sides.

22. An imager for a projection system comprising a shaped imager component physically configured with a curved top, a curved bottom and curved sides to pre-distort an input image to compensate at least in part for expected distortion in a projected image.

23. The imager of claim 22, wherein the shaped imager component has a plurality of rows of pixels.

24. The imager of claim 23, wherein the number of pixels per row are the same and wherein the spacing between each pixel within a given row is different for different rows of pixels.

25. The imager of claim 22, wherein the physical configuration comprises features determined from a modeled or actual ray trace through the projection system.

27. The method of claim 26, wherein the conducting step comprises modeling the projection system to conduct the ray trace.

28. The method of claim 26, wherein the conducting step comprises conducting an actual ray trace through the projection system.

26. A method for determining a physical configuration for a shaped imager to provide distortion correction in a projected image, comprising:

determining optical projection parameters for the projection system including projection angle and throw ratio;

conducting a ray trace of the projection system to determine distortion in a projected image; and

utilizing the ray trace to physically configure a shaped imager to correct at least in part for the distortion of the projected image.