TILED ILLUMINATION ASSEMBLY AND RELATED METHODS

• US 20080205080A1
• Filed: 06/04/2007
• Published: 08/28/2008
• Est. Priority Date: 02/23/2007
• Status: Active Grant

• Current Assignee: Rambus Delaware LLC (Rambus Inc.)
• Original Assignee: Luminus Devices Incorporated (Sanan Optoelectronics Company Limited)
• Inventors: Erchak, Alexei A., Joffe, Michael A., Doyle, David, Hoepfner, Christian, Karlicek, Robert F., Taraschi, Gianni
• Granted Patent: US 8,092,064 B2
• Time in Patent Office: Days
• US Class Current: 362/613
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0085 Means for removing heat created by the light source from the package heat extraction or cooling elements for semiconductor light sources in general H01L33/64
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133628 with cooling means
• CPC Class Codes: G02F 2201/36 Airflow channels, e.g. constructional arrangements facilitating the flow of air
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

Illumination assemblies, components, and related methods are described. An illumination assembly is provided that comprises a plurality of illumination tiles each having a light emission surface. The plurality of illumination tiles are arranged in a two-dimensional array. The illumination tiles are constructed and arranged so as to provide a substantially contiguous illumination surface comprising the light emission surfaces of the plurality of the illumination tiles. Each illumination tile is illuminated by at least one solid state light-emitting device. A method of local dimming an illumination assembly of a display (e.g., LCD) backlight unit is also provided.

Claims

1. An illumination assembly comprising:

a plurality of illumination tiles each having a light emission surface, wherein the plurality of illumination tiles are arranged in a two-dimensional array, the illumination tiles being constructed and arranged so as to provide a substantially contiguous illumination surface comprising the light emission surfaces of the plurality of the illumination tiles; and

a plurality of solid state light-emitting devices, wherein each illumination tile is illuminated by at least one of the solid state light-emitting devices.

2. The assembly of claim 1, wherein the plurality of illumination tiles are constructed and arranged such that light from one illumination tile does not couple into adjacent illumination tiles.

3. The assembly of claim 1, wherein the two-dimensional array is defined by a first axis and a second axis with at least two illumination tiles aligned along the first axis and at least two illumination tiles aligned along the second axis.

4. The assembly of claim 1, wherein each of the light-emitting devices is arranged to illuminate a single illumination tile.

5. The assembly of claim 1, wherein a single light-emitting device illuminates a single illumination tile.

6. The assembly of claim 1, wherein the plurality of illumination tiles are edge-lit by the one or more light-emitting devices.

7. The assembly of claim 1, wherein the plurality of illumination tiles are back-lit by the one or more light-emitting devices.

8. The assembly of claim 1, wherein the solid state light-emitting devices illuminating each illumination tile are disposed under the light emission surface of the illumination tile.

9. The assembly of claim 1, wherein the number of light-emitting devices per unit area of the contiguous illumination surface is less than or equal to 300.

10. The assembly of claim 1, wherein the number of light-emitting devices per illumination tile is less than or equal to 12.

11. The assembly of claim 1, further comprising members configured to align the plurality of illumination tiles.

12. The assembly of claim 1, wherein light intensity across the light emission surface of each of the plurality of illumination tiles is substantially uniform.

13. The assembly of claim 1, wherein the light intensity provided by each of the plurality of illumination tiles is individually controllable

14. The assembly of claim 1, wherein the two-dimensional array comprises a two-dimensional rectangular arrangement.

15. The assembly of claim 1, wherein the plurality of illumination tiles comprise a plurality of light guides.

16. The assembly of claim 1, wherein the plurality of illumination units comprise wavelength converting material.

17. The assembly of claim 1, wherein the illumination assembly is configured to serve as at least part of a display backlight unit.

18. An illumination assembly comprising:

a plurality of illumination tiles each having a light emission surface, wherein the plurality of illumination tiles are arranged in a two-dimensional array, the illumination tiles being constructed and arranged so as to provide an illumination surface comprising the light emission surface of the plurality of the illumination tiles; and

a plurality of solid state light-emitting devices, wherein each illumination tile is illuminated by at least one of the solid state light-emitting devices,

wherein the output light intensity varies by less than 50% across the illumination surface.

19. A method of local dimming of a display backlight unit for a plurality of pixel light valves, the method comprising:

(A) providing the display backlight unit comprising a plurality of illumination tiles each having a light emission surface, wherein the plurality of illumination tiles are arranged in a two-dimensional array, the display backlight unit further comprising a plurality of solid state light-emitting devices, wherein each illumination tile is illuminated by at least one of the solid state light emitting device;

(B) for each illumination tile of the plurality of illumination tiles, determining a highest desired brightness for light to be outputted by the pixel light valves illuminated by the illumination tile; and

(C) controlling light emission from the one or more light-emitting devices such that light output from the light emission surface of the illumination tile provides a light input to a pixel light valve set to a desired level of transmission such that the light outputted by the pixel light valve has the highest desired brightness.

20. The method of claim 19, wherein the two-dimensional array is defined by a first axis and a second axis with at least two illumination tiles aligned along the first axis and at least two illumination tiles aligned along the second axis.

21. The method of claim 19, wherein the illumination tiles are constructed and arranged so as to provide a substantially contiguous illumination surface comprising the light emission surfaces of the plurality of the illumination tiles.

22. The method of claim 19, wherein each of the light-emitting devices is arranged to illuminate a single illumination tile.

23. The method of claim 19, wherein a single light-emitting device illuminates a single illumination tile.

24. The method of claim 19, wherein (C) is performed separately for a plurality of colors.

25. The method of claim 19, wherein (C) is performed simultaneously for a plurality of colors.

26. The method of claim 19, wherein the light-emitting devices comprise light-emitting diodes.

27. A method of forming an illumination assembly, the method comprising:

providing a plurality of illumination tiles each having a light emission surface, wherein the plurality of illumination tiles are arranged in a two-dimensional array, the illumination tiles being constructed and arranged so as to provide a substantially contiguous illumination surface comprising the light emission surfaces of the plurality of the illumination tiles; and

providing a plurality of solid state light-emitting devices, wherein each illumination tile is illuminated by at least one of the solid state light-emitting devices.