Light emitting device package and backlight unit using the same

• US 8,911,160 B2
• Filed: 09/26/2006
• Issued: 12/16/2014
• Est. Priority Date: 09/27/2005
• Status: Active Grant

• Current Assignee: LG ELECTRONICS INC. AND LG INNOTEK CO., LTD, Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Electronics, Inc. (LG Corporation), LG Innotek Company Limited (LG Corporation)
• Inventors: Seo, Jung Hoon, Jang, Jun Ho
• Primary Examiner(s): Peng, Charlie
• Assistant Examiner(s): LAM, HUNG Q
• Application Number:
  US11/526,686
• Publication Number:
  US 20070070530A1
• Time in Patent Office: 3,003 Days
• Field of Search: 385/93, 385/88, 385/14, 385/33, 385/36, 362/612, 362/240, 362/241, 362/247, 362/255, 362/327, 362/329, 362/615, 362/619, 362/620, 362/623, 362/626, 359/642, 359/652, 359/811, 359/819, 359/831
• US Class Current: 385/93
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133611 including means for improving the brightness uniformity
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

An light emitting device package and a backlight unit using the same are disclosed, wherein light advancing upward from the light emitting device package can be refracted by a lens to enable the light having a uniform intensity to be emitted upwards to the advantage of efficiency and power consumption, even with a small number of light emitting devices.

Claims

1. A light emitting device package, comprising:

a substrate;

a light emitting device on the substrate; and

an optical lens over the light emitting device,

wherein the optical lens includes;

a top surface of the optical lens;

a recessed surface centrally disposed on the top surface;

a first bottom surface, wherein the first bottom surface is disposed below the recessed surface;

a second bottom surface connected to the first bottom surface, wherein the first bottom surface is centrally disposed with respect to the second bottom surface; and

a third bottom surface connected to the second bottom surface, wherein the third bottom surface is closer to the substrate than the first and second bottom surfaces,

wherein the first, second and third bottom surfaces delimit a hollow portion into or under which the light emitting device is disposed,

wherein the recessed surface converges towards a center of the recessed surface, and the first bottom surface converges towards a center of the first bottom surface,

wherein the centers of the recessed surface and the first bottom surface substantially lie on a central axis of the light emitting device, and

wherein at least one of the second and third bottom surfaces includes a curved or slanting shape.

2. The light emitting device package of claim 1, wherein the recessed surface is part of the entire top surface of the optical lens.

3. The light emitting device package of claim 1, wherein the optical lens further includes another recessed surface adjacent to the recessed surface on the top surface of the optical lens.

4. The light emitting device package of claim 3, wherein the second bottom surface is disposed below the another recessed surface.

5. The light emitting device package of claim 3, wherein the optical lens further includes a round surface adjacent to the another recessed surface on the top surface of the optical lens.

6. The light emitting device package of claim 5, wherein the third bottom surface is disposed below the round surface.

7. The light emitting device package of claim 1, wherein the optical lens further includes a first portion laterally extending in a first direction substantially perpendicular to the central axis of the light emitting device, and a second portion extending towards the substrate in a second direction substantially parallel with the central axis of the light emitting device.

8. The light emitting device package of claim 7, wherein the first portion includes the laterally outermost surface of the respective optical lens.

9. The light emitting device package of claim 7, wherein the first portion is spaced apart from the substrate.

10. The light emitting device package of claim 7, wherein the first portion is directly connected to the second portion.

11. The light emitting device package of claim 7, wherein the second portion includes the bottommost surface of the optical lens.

12. The light emitting device package of claim 7, wherein at least one of the first portion and the second portion is disposed in a lower region of the optical lens with respect to the central axis of the light emitting device.

13. The light emitting device package of claim 7, wherein the first and second portions are integral with the optical lens.

14. The light emitting device package of claim 5, wherein the another recessed surface is connected to a circumference of the round surface.

15. The light emitting device package of claim 1, wherein the recessed surface includes a curved or slanting shape.

16. The light emitting device package of claim 3, wherein the another recessed surface includes a curved or slanting shape.

17. The light emitting device package of claim 1, wherein the first bottom surface includes a curved or slanting shape.

18. The light emitting device package of claim 1, wherein the optical lens has a substantially uniform thickness.