NON-COLLINEAR LIGHT ENGINE FOR COLOR IMAGING SYSTEMS

• US 20040145703A1
• Filed: 01/24/2003
• Published: 07/29/2004
• Est. Priority Date: 01/24/2003
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Salsman, Kenneth E., OʼConnor, Michael
• Granted Patent: US 6,779,893 B2
• Time in Patent Office: Days
• US Class Current: 353/20
• CPC Class Codes: G03B 21/005 Projectors using an electronic spatial light modulator but not peculiar thereto
• CPC Class Codes: G03B 33/08 Sequential recording or projection G03B33/02, G03B33/04, G03B33/06 take precedence
• CPC Class Codes: G03B 33/14 using lenticular screens integral with film G03C
• CPC Class Codes: H04N 9/3102 using two-dimensional electronic spatial light modulators micromechanical modulators as such G02B26/0833; liquid crystal modulators as such G02F1/13
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/3111 for displaying the colours sequentially, e.g. by using sequentially activated light sources sequential projection in colour photography G03B33/08
• CPC Class Codes: H04N 9/3167 for polarizing the light beam polarizing optical systems per se G02B27/28

Abstract

For use with a color imaging system, a projection light engine may be configured in a way such that an output axis of the projection light engine may be in a non-collinear relationship with an input axis of an imaging kernel that provides image data processing to project a display. Undesired polarizations and colors may be dumped out of a critical optical path, using at least two or more ports. As a result, filters and other optical components may be optimized, significantly improving contrast ratios in a projection display system including a color imaging system with at least two panels.

Claims

1. An apparatus comprising:

a light engine having an output axis in a first orientation to provide a light source for a color imaging system having at least two or more panels; and

an imaging kernel optically couplable to the light engine to project a display based on an image data, said imaging kernel having an input axis in a second orientation substantially non-collinear to the first orientation.

2. The apparatus of claim 1 wherein the first orientation and the second orientation are substantially perpendicular to each other to reduce incorrectly polarized light and leakage thereof from said light source.

3. The apparatus of claim 1 wherein the light engine having a dump port.

4. The apparatus of claim 1 wherein the light engine having at least two dump ports.

5. The apparatus of claim 1 wherein the imaging kernel includes a first and a second spatial light modulator coupled to a polarization beam splitter.

6. The apparatus of claim 5, further comprising:

a polarizer coupled in the output axis of the light engine to receive from the light engine said light source in a red, green, and blue light color format.

7. The apparatus of claim 1, further comprising:

a color switch coupled to the light engine to provide phase switching of at least one of red, green and blue light of the red, green, and blue light color format based on an arrangement of one or more filters.

8. An apparatus comprising:

a light engine having an output axis in a first orientation, said light engine including a light source for a color imaging system having at least two or more panels;

a first polarization beam splitter coupled in the output axis to receive a light beam from the light source;

a color switch coupled to receive light reflected by the input polarization beam splitter;

a turn-around polarizer coupled to reflect light incident from the color switch back to the color switch; and

an imaging kernel having an input axis in a second orientation in a substantially non-collinear relationship with the first orientation, said imaging kernel including,

a second polarization beam splitter having a first, a second, a third, and a fourth side coupled to receive light from the light engine through the first side, and

a first spatial light modulator coupled to one of the second and third sides, wherein the imaging kernel to provide a content-modulated output beam through the fourth side.

9. The apparatus of claim 8 wherein the imaging kernel further includes:

a second spatial light modulator coupled to another of the second and third sides.

10. The apparatus of claim 9 wherein the light engine further includes:

a light pipe homogenizer; and

a lens.

11. The apparatus of claim 8 wherein the imaging kernel further includes:

a filter disposed between the first side of the second polarization beam splitter and the first polarization beam splitter;

a first quarter-wave retarder disposed between the second polarization beam splitter and the first spatial light modulator; and

a filter and a projection lens disposed in a path of the content-modulated output beam.

12. A color imaging system comprising:

a light pipe homogenizer located in a first axis to receive light from a light source;

a lens disposed in the first axis after the light pipe homogenizer;

an input polarization beam splitter disposed in the first axis after the lens;

a first dump port oriented in the first axis after the input polarization beam splitter for dumping light of a first polarization;

a color switch coupled to receive light of a second polarization from the input polarization beam splitter in the first axis;

a first quarter-wave retarder coupled to receive light from the color switch in the first axis;

a turn-around polarizer coupled to receive light from and reflect light back through the first quarter-wave retarder and the color switch in the first axis;

a polarization beam splitter having a first side perpendicular to a second axis, wherein the second axis is in a different orientation than the first axis;

a second dump port oriented in the second axis after the turn-around polarizer;

a second quarter-wave retarder and a first spatial light modulator coupled to one of a second side and a third side of the polarization beam splitter; and

an output port located at a fourth side of the polarization beam splitter.

13. The color imaging system of claim 12 wherein the second axis is in a non-collinear relationship with the first axis.

14. The color imaging system of claim 13 wherein the second axis is substantially perpendicular to the first axis.

15. The color imaging system of claim 14 further comprising:

a third quarter-wave retarder disposed in the second axis between the first side of the polarization beam splitter and the input polarization beam splitter;

a fourth quarter-wave retarder at the output port;

a brightness controller at the output port;

a clean-up polarizer at the output port; and

a projection lens in the output port.

16. The color imaging system of claim 14 further comprising:

a fourth quarter-wave retarder and a second spatial light modulator coupled to another of the second side and the third side of the polarization beam splitter.

17. The color imaging system of claim 14 wherein the color switch switches at least one of blue and green light and the first spatial light modulator comprises a blue/green spatial light modulator.

18. The color imaging system of claim 17, wherein the color switch switches blue, red, and green light and the first spatial light modulator comprises a blue/red/green spatial light modulator.

19. The color imaging system of claim 17, wherein the color switch passes red light and the apparatus further comprises:

a fourth quarter-wave retarder and a second spatial light modulator coupled to another of the second side and the third side of the polarization beam splitter.

20. A method comprising:

receiving a light beam from a light engine having an output axis of a first orientation in a panel-based color imaging system to project a display based on an image data; and

providing a color switch in a second orientation for an imaging kernel having an input axis collinear with the second orientation, wherein the first and second orientations are in a substantially non-collinear relationship.

21. The method of claim 20 including forming an optical circuit between the light engine and a projection lens that receives an output beam corresponding to the light beam passing through the color switch and the imaging kernel.

22. The method of claim 21 including:

creating a path to remove at least one of green and blue light from the optical circuit based on an incorrect polarization; and

reducing leakage of the at least one of green and blue light to increase contrast ratio.

23. A method comprising:

configuring a light engine in a first orientation for a color imaging system having at least two or more panels; and

optically coupling to the light engine a color switch in a second orientation being in a non-collinear relationship with the first orientation to project a display based on an image data.

24. The method of claim 23 including coupling to the color switch an imaging kernel having an input axis collinear with the second orientation.

25. The method of claim 24 including forming an optical circuit incorporating one or more intervening optical components between the light engine and a projection lens.

26. The method of claim 25 including:

reducing at least one of green and blue light from the optical circuit based on an incorrect polarization; and

reducing leakage of the at least one of green and blue light.

27. The method of claim 26 including providing an output beam onto the projection lens to form said display from the image data with a significantly increased contrast relative to a collinearly configured the first and second orientations.

28. The method of claim 23 including configuring the color switch to cause a light beam to pass at least twice therethrough.

29. The method of claim 23 including providing a polarizer in the optical circuit that performs both a pre-polarization before the color switch and a clean-up polarization after the color switch of the light beam.

30. The method of claim 23 including providing independent optimization of a color polarization filter, an imaging pre-filter and an imaging post-filter by reducing leakage of at least one of green and blue light.