LIGHT SOURCE ARRANGEMENT FOR BACKLIGHTING DISPLAY DEVICES

• US 20080106512A1
• Filed: 10/24/2007
• Published: 05/08/2008
• Est. Priority Date: 04/30/2005
• Status: Abandoned Application

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Schwab, Axel
• Application Number:
  US11/877,959
• Publication Number:
  US 20080106512A1
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix

Abstract

A light source arrangement for backlighting a display device, comprising a plurality of light sources and a controller that adjusts the luminous intensity of the light sources to the information to be reproduced, and a display device including said light source arrangement.

Claims

1. A light source arrangement for backlighting a display device, comprising a plurality of light sources and a controller that adjusts the luminous intensity of individual light sources or of groups of light sources based on information to be reproduced.

2. The light source arrangement as in claim 1, wherein said light sources include at least one radiation-emitting semiconductor component.

3. The light source arrangement as in claim 2, wherein each said light source includes a plurality of radiation-emitting semiconductor components.

4. The light source arrangement as in claim 1, which contains a light valve arrangement particularly comprising a plurality of light valves.

5. The light source arrangement as in claim 4, wherein one of the light sources backlights a region with a plurality of light valves.

6. The light source arrangement as in claim 1, wherein said controller controls the luminous intensity of said light sources by clocking the power supply.

7. The light source arrangement as in claim 1, wherein said controller controls the luminous intensity of said light sources by varying their operating current.

8. The light source arrangement as in claim 1, wherein said light sources are arranged in rows and columns.

9. The light source arrangement as in claim 8, wherein said controller controls the luminous intensity of said light sources by rows and columns.

10. The light source arrangement as in claim 1, wherein said light sources are arranged according to a regular grid.

11. The light source arrangement as in claim 10, wherein said grid has rectangular, parallelogrammatic, hexagonal or rhombic basic units.

12. The light source arrangement as in claim 1, wherein at least one diffuser is disposed after said light sources in the radiation direction.

13. The light source arrangement as in claim 1, wherein a homogenizing element and/or a light guide is disposed after said light sources in the radiation direction.

14. The light source arrangement as in claim 1, wherein a BEF (brightness enhancement film) is disposed after said light sources in the radiation direction.

15. The light source arrangement as in claim 1, wherein said light sources are disposed on a common carrier.

16. The light source arrangement as in claim 1, wherein said controller is configured to operate at different luminous intensities, at the same times, light sources that backlight different regions of said display device.

17. The light source arrangement as in claim 1, wherein said controller is adapted to influence the luminous intensities of said light sources in dependence on at least one of the following input variables:

contrast values within the backlit region of a said light source,

contrast values of the backlit regions of adjacent said light sources,

contrast values of the information reproduced by said display device,

ambient brightness.

18. The light source arrangement as in claim 1, wherein in the case of the reproduction of an image sequence said controller is configured to vary the luminous intensity of the individual light sources or groups of light sources in dependence on the contrast values of one image or plural images in said image sequence.

19. The light source arrangement as in claim 1, where said controller additionally drives said light valve arrangement in order to adjust the graphic resolution of the reproduced information.

20. The light source arrangement as in claim 1, wherein in the case of direct backlighting, said controller is configured to account for overlap of the emissions from adjacent light sources when adjusting the luminous intensity of the individual light sources.

21. A display device comprising a light source arrangement as in claim 1.

22. The display device as in claim 21, comprising an LCD or TFT screen.

23. The light source arrangement of claim 15, wherein the common carrier is a circuit board.