Backlight module and method of making the module

• US 20070263408A1
• Filed: 05/09/2006
• Published: 11/15/2007
• Est. Priority Date: 05/09/2006
• Status: Abandoned Application

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Chua, Janet Bee
• Application Number:
  US11/430,694
• Publication Number:
  US 20070263408A1
• Time in Patent Office: Days
• US Class Current: 362/612
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence

Abstract

A backlight module and method of making the module uses a light panel and a light source device. The light source device includes a substrate on which light-emitting dies are mounted and an encapsulation plate with depressions, which is attached to the substrate such that the depressions are positioned over the light-emitting dies.

Claims

1. A backlight module comprising:

a light panel; and

a light source device optically coupled to said light panel to transmit light into said light panel, said light source device comprising;

a substrate;

a plurality of light-emitting dies mounted on said substrate, said light-emitting dies being configured to generate original light; and

a transparent encapsulation plate over said substrate to encapsulate said light-emitting dies, said encapsulation plate including depressions on a surface facing said light-emitting dies, each of said depressions being positioned over at least one of said light-emitting dies.

2. The backlight module of claim 1 further comprising at least one wavelength-conversion region optically coupled to said light-emitting dies mounted on said substrate, said wavelength-conversion region including a photoluminescent material having a property to convert at least some of said original light into converted light.

3. The backlight module of claim 2 wherein said wavelength-conversion region is a layer of materials on a surface of one of said depressions.

4. The backlight module of claim 2 wherein said wavelength-conversion region is a portion of said encapsulation plate.

5. The backlight module of claim 2 wherein said photoluminescent material of said wavelength-conversion region includes at least one type of phosphor.

6. The backlight module of claim 1 wherein said depressions on said surface of said encapsulation plate include semispherical depressions.

7. The backlight module of claim 1 wherein said depressions on said surface of said encapsulation plate include conical depressions.

8. The backlight module of claim 1 wherein said depressions on said surface of said encapsulation plate include frusto-conical depressions.

9. The backlight module of claim 8 wherein said frusto-conical depressions includes grooves on surfaces of said frusto-conical depressions.

10. The backlight module of claim 8 wherein said frusto-conical depressions include facets on surfaces of said frusto-conical depressions.

11. The backlight module of claim 1 further comprising at least one of a diffusion plate and a Brightness Enhancement Film.

12. The backlight module of claim 1 wherein said light source device is positioned adjacent to a major surface of said light panel.

13. The backlight module of claim 1 wherein said light source device is positioned adjacent to a side surface of said light panel.

14. A method of making a backlight module, said method comprising:

forming a transparent encapsulation plate with depressions on a major surface of said transparent encapsulation plate;

mounting light-emitting dies on a substrate;

attaching said transparent encapsulation plate to said substrate such that said depressions are positioned over said light-emitting dies mounted on the substrate to form a light source device of said backlight module; and

assembling said backlight module with at least one optical component to produce said backlight module.

15. The method of claim 14 wherein said forming said transparent encapsulation plate includes creating at least one wavelength-conversion region, said wavelength-conversion region including a photoluminescent material.

16. The method of claim 15 wherein said creating said at least one wavelength-conversion region includes depositing a layer of materials on a surface of one of said depressions.

17. The method of claim 15 wherein said creating said at least one wavelength-conversion region includes embedding said photoluminescent material into said encapsulation plate.

18. The method of claim 14 wherein said forming said transparent encapsulating plate includes forming said transparent encapsulation plate with semispherical depressions, conical depressions or frusto-conical depressions.

19. The method of claim 18 wherein said frusto-conical depressions include grooves or facets on surfaces of said frusto-conical depressions.

20. The method of claim 14 wherein said assembling includes assembling said light source device with at least one of a diffusion plate and a Brightness Enhancement Film to produce said backlight module.