Light emitting device and display comprising a plurality of light emitting components on mount

• US 8,610,147 B2
• Filed: 09/14/2009
• Issued: 12/17/2013
• Est. Priority Date: 07/29/1996
• Status: Expired due to Fees

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Shimizu, Yoshinori, Sakano, Kensho, Noguchi, Yasunobu, Moriguchi, Toshio
• Primary Examiner(s): Nguyen, Ha Tran T
• Assistant Examiner(s): Gupta, Raj R
• Application Number:
  US12/559,042
• Publication Number:
  US 20100001258A1
• Time in Patent Office: 1,555 Days
• Field of Search: 257/88, 257/89, 257/99
• US Class Current: 257/98
• CPC Class Codes: C09K 11/7767 Chalcogenides
• CPC Class Codes: C09K 11/7774 Aluminates
• 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 6/0025 Diffusing sheet or layer; Prismatic sheet or layer
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: H01J 29/20 characterised by the luminescent material
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45169 Platinum (Pt) as principal constituent
• 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 2224/48257 connecting the wire to a die 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 24/45 of an individual wire connector
• 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 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 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01021 : Scandium [Sc]
• CPC Class Codes: H01L 2924/01067 : Holmium [Ho]
• CPC Class Codes: H01L 2924/01068 : Erbium [Er]
• CPC Class Codes: H01L 2924/12036 : PN diode
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/15747 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/20751 : larger or equal to 10 microns less than 20 microns
• CPC Class Codes: H01L 2924/20752 : larger or equal to 20 microns less than 30 microns
• CPC Class Codes: H01L 2924/20753 : larger or equal to 30 microns less than 40 microns
• CPC Class Codes: H01L 2924/20754 : larger or equal to 40 microns less than 50 microns
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• 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 33/501 : characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/504 : Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H05B 33/14 : characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

A light emitting device containing a semiconductor light emitting component and a phosphor, the phosphor is capable of absorbing a part of light emitted by the light emitting component and emitting light of a wavelength different from that of the absorbed light, is provided. A straight line connecting a point of chromaticity corresponding to a spectrum generated by the light emitting component and a point of chromaticity corresponding to a spectrum generated by the phosphor is substantially along a black body radiation locus in a chromaticity diagram.

Claims

1. A light emitting device comprising:

a mount,

a plurality of light emitting chips mounted on said mount in a recess formed in said mount,

a transparent material directly covering said light emitting chips, said transparent material including a first region and a second region, wherein

said first region is in the vicinity of at least one of said light emitting chips, and

said second region is in the vicinity of the surface of said transparent material, closer to the surface of said transparent material than said first region, and

a phosphor contained in said transparent material and absorbing a part of light emitted by said light emitting chips and emitting light of wavelength different from that of the absorbed light,

wherein a concentration of said phosphor in said first region in said transparent material is larger than a concentration of said phosphor in said second region in said transparent material, wherein the concentration of said phosphor in said second region in said transparent material is larger than zero,

wherein the main emission peak of said light emitting chips is within the range from 400 nm to 530 nm, and

wherein said mount comprises a material which is one of iron, copper, copper-clad iron, copper-clad tin and metalized ceramic.

2. The light emitting device according to claim 1, wherein said mount comprises a metalized ceramic.

3. The light emitting device according to claim 1, wherein said phosphor comprises two or more kinds of fluorescent materials.

4. The light emitting device according to claim 1, wherein said phosphor comprises an yttrium-aluminum-garnet fluorescent material containing Y and Al.

5. The light emitting device according to claim 1, wherein said phosphor has a crystal structure.

6. The light emitting device according to claim 1, wherein said phosphor diffuses said light emitted from said light emitting chips.

7. The light emitting device according to claim 1, wherein said light emitting chips comprise a light emitting layer of single quantum well or multi quantum well structure.

8. The light emitting device according to claim 1, wherein said light emitting chips comprise InGaN.

9. The light emitting device according to claim 1, wherein said light emitting chips comprise a sapphire substrate.

10. The light emitting device according to claim 1, wherein said transparent material is selected from the group consisting of epoxy resin, urea resin, silicone resin and glass.

11. The light emitting device according to claim 1, wherein said transparent material contains a coloration agent.

12. The light emitting device according to claim 1, wherein said mount is plated with silver, copper or gold.

13. The light emitting device according to claim 1, wherein said transparent material contains a dispersant.

14. The light emitting device according to claim 13, wherein said dispersant is selected from the group consisting of barium titanate, titanium oxide, aluminum oxide and silicon dioxide.

15. The light emitting device according to claim 1, wherein said light emitting chips emit a light having a spectrum with a peak in the range from 420 to 490 nm, said phosphor emits light having a spectrum with a peak in the range from 510 to 600 nm and a tail continuing beyond 700 nm, and said spectrum of the light emitted from said phosphor and said spectrum of the light emitted from said light emitting chips overlap with each other to make a continuous combined spectrum.

16. The light emitting device according to claim 15, wherein said spectrum of the light emitted from said phosphor has a peak in the range from 530 to 570 nm and a tail continuing beyond 700 nm.

17. The light emitting device according to claim 15, wherein a color of said combined spectrum is white.

18. A light emitting device comprising:

a mount,

a plurality of light emitting chips mounted on said mount in a recess formed in said mount,

a transparent material directly covering said light emitting chips, said transparent material including a first region and a second region, wherein

said first region is in the vicinity of at least one of said light emitting chips, and

said second region is in the vicinity of the surface of said transparent material, closer to the surface of said transparent material than said first region, and

a phosphor contained in said transparent material and absorbing a part of light emitted by said light emitting chips and emitting light of wavelength different from that of the absorbed light,

wherein a concentration of said phosphor in said first region in said transparent material is larger than a concentration of said phosphor in said second region in said transparent material, wherein the concentration of said phosphor in said second region in said transparent material is larger than zero,

wherein the main emission peak of said light emitting chips is within the range from 400 nm to 530 nm, and

a thermal conductivity of said mount is not less than 0.01 cal/(s)(cm²)(°

C./cm).

19. The light emitting device according to claim 18, wherein said mount is plated with silver, copper or gold.

20. A light emitting device comprising:

a mount,

a plurality of light emitting chips mounted on said mount,

a plurality of inner leads electrically separated from said mount, each inner lead being connected to one of said light emitting chips,

a transparent material directly covering said light emitting chips, said transparent material including a first region and a second region, wherein

said first region is in the vicinity of at least one of said light emitting chips, and

said second region is in the vicinity of the surface of said transparent material, closer to the surface of said transparent material than said first region, and

a phosphor contained in said transparent material and absorbing a part of light emitted by said light emitting chips and emitting light of wavelength different from that of the absorbed light,

wherein a concentration of said phosphor in said first region in said transparent material is larger than a concentration of said phosphor in said second region in said transparent material, wherein the concentration of said phosphor in said second region in said transparent material is larger than zero,

wherein the main emission peak of said light emitting chips is within the range from 400 nm to 530 nm, and

wherein said mount comprises a material which is one of iron, copper, copper-clad iron, copper-clad tin and metalized ceramic.

21. A light emitting device comprising:

a mount,

a plurality of light emitting chips mounted on said mount, a plurality of inner leads electrically separated from said mount, each inner lead being connected to one of said light emitting chips,

a transparent material directly covering said light emitting chips, said transparent material including a first region and a second region, wherein

said first region is in the vicinity of at least one of said light emitting chips, and

said second region is in the vicinity of the surface of said transparent material, closer to the surface of said transparent material than said first region, and

a phosphor contained in said transparent material and absorbing a part of light emitted by said light emitting chips and emitting light of wavelength different from that of the absorbed light,

wherein a concentration of said phosphor in said first region in said transparent material is larger than a concentration of said phosphor in said second region in said transparent material, wherein the concentration of said phosphor in said second region in said transparent material is larger than zero,

wherein the main emission peak of said light emitting chips is within the range from 400 nm to 530 nm, and

a thermal conductivity of said mount is not less than 0.01 cal/(s)(cm²)(°

C./cm).