Illumination module for sectional illumination

• US 8,421,952 B2
• Filed: 12/03/2007
• Issued: 04/16/2013
• Est. Priority Date: 12/03/2007
• Status: Expired due to Fees

• Current Assignee: Philips Lumileds Lighting Company LLC (Apollo Global Management, Inc.)
• Original Assignee: Philips Lumileds Lighting Company LLC (Apollo Global Management, Inc.)
• Inventors: Harbers, Gerard, Yagi, Takaaki, Smitt, Johannes W. H. S., Bierhuizen, Serge J.
• Primary Examiner(s): Healy, Brian
• Assistant Examiner(s): EL SHAMMAA, MARY A
• Application Number:
  US11/949,697
• Publication Number:
  US 20090141212A1
• Time in Patent Office: 1,961 Days
• Field of Search: 349 61- 64, 349/68, 349/69, 349/56, 349/113, 362/97.1, 362/97.2
• US Class Current: 349/61
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light

Abstract

A backlight for a display includes a plurality of illumination modules, each illumination module including a light source and a reflective member. A portion of the reflective member is disposed over the light source. A liquid crystal display panel is disposed over the plurality of illumination modules. The reflective member is configured such that a majority of light from the light source is directed parallel to the liquid crystal display panel, to provide uniform illumination of the liquid crystal display panel. In some embodiments, the light source is at least one semiconductor light emitting diode.

Claims

1. A structure comprising:

a plurality of illumination modules, each illumination module comprising;

a light source;

a first reflective member that reflects light emitted from the light source; and

a second reflective member that includes a reflective surface that includes a first portion and a second portion, wherein each portion reflects light that is reflected from the first reflective member, the first portion being more specular reflecting than the second portion and the second portion being more diffuse reflecting than the first portion; and

a liquid crystal display panel disposed over the plurality of illumination modules.

2. The structure of claim 1 wherein the light source is disposed in a corner of the illumination module.

3. The structure of claim 1 wherein the light source is disposed on an edge of the illumination module.

4. The structure of claim 1 wherein the light source comprises at least one semiconductor light emitting diode.

5. The structure of claim 1 wherein the light source comprises at least one red-emitting semiconductor light emitting diode, at least one green-emitting semiconductor light emitting diode, and at least one blue-emitting semiconductor light emitting diode.

6. The structure of claim 1 wherein each illumination module in the structure has the same size and shape.

7. The structure of claim 1 wherein:

a first illumination module is located proximate a center of the liquid crystal display panel;

a second illumination module is located proximate an edge of the liquid crystal display panel; and

the first illumination module has a smaller area than the second illumination module.

8. The structure of claim 1 wherein at least one illumination module is substantially square and between 50 and 100 mm long on a side of the square.

9. The structure of claim 1 wherein each illumination module has a thickness less than 20 mm.

10. The structure of claim 1 wherein the reflective member is curved.

11. The structure of claim 1 wherein the first portion is disposed between the light source and the second portion.

12. The structure of claim 1 further comprising a wavelength-converting material disposed on at least a portion of the reflective member.

13. The structure of claim 1 further comprising a wavelength-converting material spaced apart from the plurality of illumination modules.

14. The structure of claim 1 wherein:

a first portion of the liquid crystal display panel is aligned over a first illumination module;

a second portion of the liquid crystal display panel is aligned over a second illumination module; and

the first illumination module is configured such that a portion of light emitted from the light source of the first illumination module is incident on the second portion of the liquid crystal display panel.

15. The structure of claim 14 wherein the plurality of illumination modules are configured such that between 5% and 60% of light incident on the first portion of the liquid crystal display panel is emitted from light sources other than the light source of the first illumination module.

16. The structure of claim 1 further comprising a diffuser disposed between the plurality of illumination modules and the liquid crystal display panel.

17. The structure of claim 16 wherein the diffuser is spaced between 0.5 to 10 mm from the plurality of illumination modules.

18. The structure of claim 16 wherein the diffuser is patterned.

19. A structure comprising:

a plurality of illumination modules, each illumination module comprising;

a light source;

a first reflective member that reflects light from the light source; and

a second reflective member that includes a reflective surface that includes a first portion and a second portion wherein each portion reflects light from the light source that is reflected by the first reflective member, wherein the first portion is more specular reflecting than the second portion and the second portion is more diffuse reflecting than the first portion; and

a liquid crystal display panel disposed over the plurality of illumination modules.

20. The structure of claim 19 wherein:

a first portion of the liquid crystal display panel is aligned over a first illumination module;

a second portion of the liquid crystal display panel is aligned over a second illumination module; and

the first illumination module is configured such that a portion of light emitted from the light source of the first illumination module is incident on the second portion of the liquid crystal display panel.

21. A structure comprising:

a plurality of illumination modules, each illumination module including;

a light source;

a first reflective member that reflects light emitted from the light source in a first direction; and

a second reflective member that includes a reflective surface that includes a first portion and a second portion, wherein each portion reflects the light from the first reflective member in a second direction that differs substantially from the first direction, the first portion being more specular reflecting than the second portion and the second portion being more diffuse reflecting than the first portion; and

a liquid crystal display panel disposed over the plurality of illumination modules.

22. The structure of claim 21, wherein the first direction is toward the liquid crystal display panel.

23. The structure of claim 21, wherein the first portion is closer to the first light source than the second portion.

24. The structure of claim 21, wherein the second portion includes a printed diffusion pattern.

25. The structure of claim 21, wherein the second portion includes a corrugated diffusion pattern.