Light emitting device, backlight unit, liquid crystal display apparatus, and lighting apparatus

• US 8,450,929 B2
• Filed: 06/24/2011
• Issued: 05/28/2013
• Est. Priority Date: 06/28/2010
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Ishimori, Atsuyoshi, Ueno, Yasuharu, Kobashi, Kazuyuki, Kanayama, Yoshihiko
• Primary Examiner(s): Williams, Joseph L
• Application Number:
  US13/394,351
• Publication Number:
  US 20120169968A1
• Time in Patent Office: 704 Days
• Field of Search: 313/512, 313504-506, 257/79, 445 23- 25
• US Class Current: 313/512
• CPC Class Codes: G02B 6/0023 provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/009 of the light source in the package G02B6/0021 takes precedence
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• 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

Provided is a light-emitting device which can reduce grainy texture, suppress color unevenness and luminance unevenness. A light-emitting device according to the present invention includes: a board; a plurality of light-emitting parts each of which includes (i) a LED chip mounted on the board and (ii) a phosphor-containing resin including a light wavelength converter and covering the LED chip. Further, the light-emitting device includes a light-guiding member provided on the board, between the light-emitting parts which are adjacent to each other. Furthermore, the light-guiding member is formed to cover part of the phosphor-containing resin.

Claims

1. A light-emitting device comprising:

a board;

a plurality of light-emitting parts each of which includes (i) a semiconductor light-emitting element mounted on said board and (ii) a wavelength conversion layer including a light wavelength converter and covering said semiconductor light-emitting element; and

a plurality of light-guiding members each of which is provided on said board, between said light-emitting parts which are adjacent to each other,

wherein each of said light-guiding members is formed to cover part of said wavelength conversion layer included in said light-emitting part.

2. The light-emitting device according to claim 1,

wherein said light-guiding member is adjacent to said wavelength conversion layer.

3. The light-emitting device according to claim 1,

wherein at least an end portion of said light-guiding member on a side of said semiconductor light-emitting element is on a side of said semiconductor light-emitting element with respect to a normal that extends from an intersection between said board and one of (i) an outline of said light-emitting part and (ii) an extension of the outline.

4. The light-emitting device according to claim 1,

wherein said light-guiding member connects said light-emitting parts which are adjacent to each other.

5. The light-emitting device according to claim 1,

wherein said light-guiding member has a function of diffusing light that is guided in said light-guiding member.

6. The light-emitting device according to claim 5,

wherein said light-guiding member includes a diffusion material.

7. The light-emitting device according to claim 6,

wherein density of said diffusion material in said light-guiding member is higher as a distance from said semiconductor light-emitting element is greater.

8. The light-emitting device according to claim 1,

wherein

n1≦

n2

is satisfied, when a refractive index of said wavelength conversion layer is denoted by n1 and a refractive index of said light-guiding member is denoted by n2.

9. The light-emitting device according to claim 1,

wherein said light-guiding member is a transparent resin.

10. The light-emitting device according to claim 1,

wherein said wavelength conversion layer is a phosphor layer including a phosphor which is excited by light of said semiconductor light-emitting element.

11. The light-emitting device according to claim 1,

wherein said wavelength conversion layer is dome-shaped.

12. The light-emitting device according to claim 4,

wherein said board is elongated, and

said light-emitting parts and said light-guiding member are arranged linearly in a row along a longer direction of said board.

13. The light-emitting device according to claim 12,

wherein

0≦

D1/L1≦

L1/2n

is satisfied, when a distance between said light-guiding members which are adjacent to each other is denoted by D1, a length of said board in the longer direction is denoted by L1, and the number of said semiconductor light-emitting elements is denoted by n.

14. The light-emitting device according to claim 1,

wherein

10≦

L1/L2

is satisfied, when a length of said board in a longer direction is denoted by L1, and a length of said board in a shorter direction is denoted by L2.

15. The light-emitting device according to claim 1,

wherein

0<

h2/h1≦

1

is satisfied, when a height of said light-emitting part is denoted by h1 and a height of said light-guiding member is denoted by h2.

16. The light-emitting device according to claim 1,

wherein a groove for regulating a position of an end portion of said light-guiding member is formed on said board.

17. A backlight unit comprising

the light-emitting device according to claim 1.

18. A liquid crystal display apparatus comprising:

the backlight unit according to claim 17; and

a liquid crystal panel provided on an optical path of light emitted from said backlight unit.

19. A lighting apparatus comprising

the light-emitting device according to claim 1.