Multi-mode color filter

• US 7,557,992 B2
• Filed: 11/02/2004
• Issued: 07/07/2009
• Est. Priority Date: 12/31/2001
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Davis, Michael T.
• Primary Examiner(s): MAI, HUY KIM
• Application Number:
  US10/979,430
• Publication Number:
  US 20050063082A1
• Time in Patent Office: 1,708 Days
• Field of Search: 359/634, 359887-891, 349/104, 349/106, 348268-271, 348/273, 348276-280, 348/742, 348/743
• US Class Current: 359/634
• CPC Class Codes: G02B 26/008 in the form of devices for effecting sequential colour changes, e.g. colour wheels
• CPC Class Codes: H04N 9/3114 by using a sequential colour filter producing one colour at a time
• CPC Class Codes: H04N 9/3117 by using a sequential colour filter producing two or more colours simultaneously, e.g. by creating scrolling colour bands

Abstract

A multi-mode color filter 400 having an inner hub region 402 used to mount the color filter 400 to a motor shaft. A first track 404 and a second track 406 of color filter segments are formed on the color filter, as is an optional clear track 406. The first and second tracks each have a different set of color filters. One set of filters is chosen to improve image brightness, another set is selected to improve color saturation. Typically, the set of filters used to improve brightness includes one or more clear segments, while the set of filters selected to improve color saturation does not. Depending on the image being projected, the user or the display controller moves the color wheel to select a particular filter set.

Claims

1. A color filter comprising:

a rotatable substrate;

at least two tracks of color filters;

at least one of said tracks of color filters comprising a plurality of curved filter segments.

2. The color filter of claim 1, at least one of said tracks of filters comprising primary color filters.

3. The color filter of claim 1, at least one of said tracks of filters comprising primary color filters and a clear filter.

4. The color filter of claim 1, comprising a clear track.

5. The color filter of claim 1, at least one of said color filters comprising a dichroic filter deposited on a substrate.

6. The color filter of claim 1, at least two of said color filters comprising dichroic filters deposited on a common substrate.

7. The color filter of claim 1, said rotatable substrate having a drum shape.

8. A display system comprising:

a light source producing a beam of light;

a color filter receiving said beam of light and producing a filtered beam of light, said color filter comprising;

a rotatable substrate;

at least two tracks of color filters;

at least one of said tracks of color filters comprising a plurality of curved filter segments; and

a spatial light modulator receiving said filtered beam of light and selectively modulating said filtered beam of light in response to electronic image data.

9. The display system of claim 8, comprising:

a projection lens receiving said modulated light beam and focusing said modulated light beam on an image plane.

10. The display system of claim 8, at least one of said tracks of filters comprising primary color filters.

11. The display system of claim 8, at least one of said tracks of filters comprising primary color filters and a clear filter.

12. The display system of claim 8, comprising a clear track.

13. The display system of claim 8, at least one of said color filters comprising a dichroic filter deposited on a substrate.

14. The display system of claim 8, at least two of said color filters comprising dichroic filters deposited on a common substrate.

15. The display system of claim 8, said rotatable substrate having a drum shape.

16. A method of producing a color image, comprising:

providing a beam of white light;

providing a drum shape color filter having at least two tracks of color filters;

moving said color filter to position one of said first and second tracks in said beam of light;

spinning said color filter to sequentially filter said beam of light;

selectively modulating said filtered beam of light in response to electronic image data; and

focusing said selectively modulated beam of light onto an image plane.

17. The method of claim 16, said providing a color filter having at least two tracks of color filters comprising:

providing a color filter having at least one track comprised of primary color filters.

18. The method of claim 16, said providing a color filter having at least two tracks of color filters comprising:

providing a color filter having at least one track of color filters comprised of a clear filter.

19. The method of claim 16, said providing a color filter having at least two tracks of color filters comprising:

providing a color filter having a clear track.

20. The method of claim 16, said step of providing a color filter comprising providing a drum shaped color filter having at least two tracks of color filter segments, at least one of said track comprised of color filter segments curved in a direction parallel to an axis of said drum.