Illumination system with integrated heat dissipation device for use in display systems employing spatial light modulators

• US 7,434,946 B2
• Filed: 06/17/2005
• Issued: 10/14/2008
• Est. Priority Date: 06/17/2005
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Huibers, Andrew
• Primary Examiner(s): BLACKMAN, ROCHELLE ANN J
• Application Number:
  US11/156,123
• Publication Number:
  US 20060285083A1
• Time in Patent Office: 1,215 Days
• Field of Search: 353/84, 353/20, 353/30, 353/31, 353/37, 353/52, 353/56, 353/98, 353/99, 353/119, 353/122, 353/102, 348/742, 348/743, 348/744, 348/748, 348/759, 348/771, 349 5- 9, 349/161, 362/257, 362/264, 362/294, 362/317, 362/341, 362/373, 362/345, 362/551, 362/560, 362/561, 362/600, 362/615, 362/623, 362/624, 362/580, 358/15, 358/34, 358/133
• US Class Current: 353/102
• CPC Class Codes: G03B 21/16 Cooling; Preventing overheating
• CPC Class Codes: G03B 21/208 Homogenising, shaping of the illumination light

Abstract

Disclosed herein is an illumination system for use in display systems employing spatial light modulators. The illumination system comprises a fastening mechanism for securing the bonding of the walls of the light integrator of the illumination system. A heat dissipation mechanism can be alternatively provided for reducing the temperature of the illumination system by dissipating the heat thereof.

Claims

1. A light integrator for use in a display system employing a spatial light modulator, comprising:

a plurality of walls each having a reflective surface, wherein the walls are bonded together to form a tunnel whose interior surfaces are the reflective surfaces;

a fastening mechanism comprising a bonding agent that bonds the plurality of walls together and has a melting temperature 150°

C. or higher, wherein the bonding agent is a metal solder or a glass frit; and

a heat dissipation mechanism directly attached to or integrated in at least one of the plurality of walls of the light integrator for reducing the temperature of the walls by dissipating the heat thereof.

2. The light integrator of claim 1, wherein the fastening mechanism comprises a clamp.

3. The light integrator of claim 1, wherein the bonding agent has a melting temperature that is 200°

C. or higher.

4. The light integrator of claim 3, wherein the bonding agent has a melting temperature that is 250°

C. or higher.

5. The light integrator of claim 1, wherein the heat dissipation mechanism comprises a heat sink attached to the light integrator.

6. The light integrator of claim 1, wherein the heat dissipation mechanism comprises a heat fin attached to one of the walls.

7. The light integrator of claim 1, wherein the heat dissipation mechanism comprises a heat dissipation duct in one of the walls.

8. The light integrator of claim 1, wherein the heat dissipation duct is a hole whose one end is disposed close to the reflective surface of one of the walls but not penetrating through the reflective surface and the other end is opened.

9. The light integrator of claim 1, wherein the walls further comprise a light blocking film on a major exterior surface thereof.

10. The light integrator of claim 1, wherein one of the reflective surfaces comprises a movable portion having at least two non-parallel operation positions.

11. An illumination system comprising a source-pipe integrator that comprises:

a thermal light source producing white light; and

a light integrator of claim 1, wherein the light integrator has an entrance aperture that is directly bonded to the exit aperture of the thermal light source.

12. The illumination system of claim 11, wherein the thermal light source is an arc lamp.

13. The illumination system of claim 11, further comprising:

a color filter having a set of primary color segments.

14. The illumination system of claim 13, wherein the light integrator has an exit aperture facing a segment of the color filter.

15. A projection system, comprising:

an illumination system of claim 11 producing an illumination light beam;

a spatial light modulator for modulating the illumination light beam; and

a display target on which the modulated illumination light beam is projected.

16. The projection system of claim 15, wherein the spatial light modulator is a liquid crystal.

17. The projection system of claim 15, wherein the spatial light modulator is a liquid crystal on silicon.

18. The projection system of claim 15, wherein the spatial light modulator comprises an array of reflective deflectable micromirrors.

19. A light integrator comprising:

a plurality of walls each having a reflective surface bonded together forming a tunnel with a substantially rectangular cross section, wherein the walls are connected to each other at end surfaces thereof with a bonding agent that is a metal solder or glass fit; and

a heat dissipation mechanism directly attached to or integrated in at least one of the plurality of walls of the light integrator for reducing the temperature of the walls by dissipating the heat thereof.

20. The light integrator of claim 19, further comprising:

a fastening mechanism that comprises a clamp.

21. The light integrator of claim 19, wherein the bonding agent has a melting temperature that is 150°

C. or higher.

22. The light integrator of claim 19, wherein the bonding agent has a melting temperature that is 200°

C. or higher.

23. The light integrator of claim 19, wherein the heat dissipation mechanism comprises a heat sink attached to the light integrator.

24. The light integrator of claim 19, wherein the heat dissipation mechanism comprises a heat fin attached to one of the walls.

25. The light integrator of claim 19, wherein the heat dissipation mechanism comprises a heat dissipation duct in one of the walls.

26. The light integrator of claim 25, wherein the heat dissipation duct is a hole whose one end is disposed close to the reflective surface of one of the walls but not penetrating through the reflective surface and the other end is opened.

27. The light integrator of claim 19, wherein the walls further comprise a light blocking film on a major exterior surface thereof.

28. A projection system comprising:

a light source for providing a beam of light;

a light pipe capable of changing a cross-section of the beam of light;

a color wheel for providing light of different colors;

a spatial light modulator upon which is incident the light of different colors; and

projection optics for directing light onto a target,

wherein the light pipe has four reflective walls bonded together with a substantially rectangular cross section, wherein the four walls are connected to each other at end surfaces thereof with a bonding agent that is a metal solder or glass frit, and wherein the light pipe has a heat dissipation mechanism directly attached to or integrated in at least one of the walls for reducing the temperature of the walls by dissipating the heat thereof.

29. The system of claim 28, wherein the color wheel is positioned between the light pipe and the spatial light modulator.