Color permuting light projector

• US 7,543,943 B1
• Filed: 10/28/2005
• Issued: 06/09/2009
• Est. Priority Date: 10/28/2005
• Status: Active Grant

• Current Assignee: Dolby International AB (Dolby Laboratories Incorporated)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Hubby, Laurence Meade Jr.
• Primary Examiner(s): BLACKMAN, ROCHELLE ANN J
• Application Number:
  US11/261,323
• Time in Patent Office: 1,320 Days
• Field of Search: 353/84, 353 30- 33, 353/37, 353/38, 353/81, 353/98, 353/99, 353/102, 359/196, 359/197, 359/204, 359/205, 359/209, 359/210, 359/216, 359/226, 359/227, 359/230, 359/235, 359/618, 359/634, 359/636, 359638-640, 348/739, 348/742, 348/743, 348/744, 348757-759, 348/771, 362/257, 362/268, 362/269, 362/271, 362/272, 362/277, 362/279, 362282-284, 362/307, 362/317, 362/321, 362/324, 362/326, 362/330, 362/332, 362/333, 362/335, 349/5, 349/7
• US Class Current: 353/84
• CPC Class Codes: G02B 26/008 in the form of devices for effecting sequential colour changes, e.g. colour wheels
• CPC Class Codes: G02B 27/1033 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/126 The splitting element being a prism or prismatic array, including systems based on total internal reflection
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• 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 light projector includes a light source configured to output a light beam, a display screen configured to display a color image containing pixels, and a color filter positioned between the light source and the projection screen. The light projector also includes a device for sequentially permuting colors of the pixels for a plurality of frames. The device includes at least one of a device for shifting a position of the color filter with respect to the light beam and a device for shifting a path of the light beam that passes through the color filter.

Claims

1. A light projector comprising:

a light source configured to output a light beam;

a display screen configured to display a color image containing pixels;

a color filter positioned between the light source and the projection screen, said color filter comprising a mosaic of tiles having one of “

n”

number of colors, wherein “

n”

is equal to the number of color components used to display the color image on the display screen, and wherein the tiles are arranged in a spatially intermixed color pattern;

a device for sequentially permuting colors of the pixels for a plurality of frames, said device comprising a mechanical device for shifting the position of the color filter; and

a light valve positioned between the light source and the color filter, such that, the light beam from the light source impinges upon the light valve prior to passing through the color filter.

2. The light projector according to claim 1, wherein the tiles are arranged along successive rows of the spatially intermixed color pattern such that each row contains tiles having sequentially arranged colors such that “

n”

number of tiles have different colors.

3. The light projector according to claim 1, wherein the light valve comprises a digital micromirror device.

4. The light projector according to claim 1, wherein the mechanical device comprises a piezoelectric bimorph translator configured to shift the position of the color filter based upon the received level of voltage.

5. The light projector according to claim 1, wherein the device for sequentially permuting colors further comprises a wobble plate configured to vary the sideways position of the path at which the light beam exits the wobble plate, wherein the sideways positions of the light beam depend upon the angle of the wobble plate, and wherein the sideway positions of the light beam are varied for the plurality of frames.

6. A method for permuting colors in a color image having pixels, said method comprising:

positioning a light valve in a light beam path;

positioning a color filter having spatially intermixed colors per pixel downstream of the light valve along the light beam path; and

sequentially permuting colors of the pixels for a plurality of frames to display the color image by shifting the position of the color filter using a mechanical device, wherein the step of shifting the position of the color filter further comprises;

shifting the color filter to a first position to display a first color at a first pixel location during a first frame;

shifting the color filter to a second position to display a second color at the first pixel location during a second frame; and

shifting the color filter to a third position to display a third color at the first pixel location during a third frame.

7. The method according to claim 6, wherein the step of sequentially permuting the colors further comprises sequentially permuting the colors for a number of times equal to the number of colors used to display the color image, wherein the color filter is configured to display each of the number of colors in the pixels following performance of a sequential permutation.

8. The method according to claim 6, wherein the mechanical device comprises a piezoelectric bimorph translator, wherein the step of shifting the position of the color filter comprises varying a voltage supplied to the piezoelectric bimorph translator to shift the position of the color filter.

9. The method according to claim 6, further comprising:

positioning a wobble plate to vary the sideways position of the path at which the light beam exits the wobble plate; and

wherein the step of shifting the light beam path comprises varying the sideways position of the wobble plate to vary the sideway positions at which the light beam that passes through the color filter are displayed during the plurality of frames.

10. A system for permuting colors in a color image having pixels, said system comprising:

means for filtering a light beam supplied from a light valve into a plurality of colors; and

means for sequentially permuting the colors of the pixels, said means for sequentially permuting comprising a mechanical device for shifting the position of the means for filtering, wherein the means for sequentially permuting the colors of the pixels is configured to;

shift the means for filtering to a first position to display a first color at a first pixel location during a first frame;

shift the means for filtering to a second position to display a second color at the first pixel location during a second frame; and

shift the means for filtering to a third position to display a third color at the first pixel location during a third frame.

11. A computer readable storage medium on which is embedded one or more computer programs, said one or more computer programs implementing a method for permuting colors in a color image having pixels, wherein the color image is displayed through a light valve positioned in a light beam path and a color filter having spatially intermixed colors per pixel positioned downstream of the light valve along the light beam path, said one or more computer programs comprising a set of instructions for:

shifting the position of the color filter using a mechanical device to sequentially permute colors of the pixels for a plurality of frames to display the color image, wherein the step of shifting the position of the color filter further comprises;

shifting the color filter to a first position to display a first color at a first pixel location during a first frame;

shifting the color filter to a second position to display a second color at the first pixel location during a second frame; and

shifting the color filter to a third position to display a third color at the first pixel location during a third frame.