Light emitting device

• US 10,180,213 B2
• Filed: 08/02/2017
• Issued: 01/15/2019
• Est. Priority Date: 12/16/2005
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Tanda, Yuichiro, Matsushita, Toshio
• Primary Examiner(s): GRAMLING, SEAN P
• Application Number:
  US15/666,578
• Publication Number:
  US 20170328523A1
• Time in Patent Office: 531 Days
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/235 Details of bases or caps, i.e. the parts that connect the light source to a fitting; Arrangement of components within bases or caps F21K9/238 takes precedence
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 19/006 of point-like light sources, e.g. incandescent or halogen lamps, with screw-threaded or bayonet base of sources having contact pins, wires or blades F21V19/0005; of LEDs or sources mounted on printed-circuit board F21V19/001
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 31/005 Sealing arrangements therefor
• CPC Class Codes: F21V 9/30 Elements containing photoluminescent material distinct from or spaced from the light source shades F21V1/17; globes, bowls or cover glasses F21V3/08, F21V3/12; refractors F21V5/10; reflectors F21V7/26, F21V7/30; elements with provision for controlling the spectral properties or intensity F21V9/40
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: F21Y 2101/00 Point-like light sources
• CPC Class Codes: F21Y 2109/00 Light sources with light-generating elements disposed on transparent or translucent supports or substrates
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/30 Semiconductor lasers
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/48095 Kinked
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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 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 2924/01004 : Beryllium [Be]
• CPC Class Codes: H01L 2924/0102 : Calcium [Ca]
• CPC Class Codes: H01L 2924/01063 : Europium [Eu]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 33/501 : characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/505 : characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/507 : the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/508 : having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/54 : having a particular shape
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05B 33/04 : Sealing arrangements , e.g. against humidity

Abstract

A light emitting device including a transparent board elongated in a first direction and having a first surface and an opposite second surface. Light emitting elements are arranged in the first direction on the first surface side of the board. A transparent bulb houses the board and the elements. A base is connected to the bulb, and leads electrically connect the elements to the base. The leads have a first end portion connected to the base, and an opposite second end portion. Conductive members are respectively connected to the second end portions of the leads, and the conductive members are arranged at both side of the elements on the board in the first direction. A first wavelength converting member is provided on the first surface and seals the elements. The first wavelength converting member is elongated in the first direction. The second surface of the board faces the base.

Claims

1. A light emitting device comprising:

a transparent board having a first direction and a second direction which is perpendicular to the first direction, the transparent board being elongated longer in the first direction than in the second direction and having a first surface on a first surface side thereof and a second surface on a second surface side thereof that is opposite to the first surface side;

a plurality of light emitting elements arranged in the first direction on the first surface side of the transparent board in the manner that a number of the light emitting elements in the first direction is larger than that in the second direction;

a transparent bulb housing the transparent board and the plurality of light emitting elements;

a base connected to the transparent bulb, the base having terminals and configured to be threadedly engaged with a conventional socket for a light bulb;

conductive members arranged at both side of the plurality of light emitting elements on the transparent board in the first direction;

a plurality of leads electrically connecting the plurality of light emitting elements to the base, the plurality of leads respectively having;

an end portion connected to a respective conductive member of the conductive members; and

a lower portion extending from the end portion toward the base; and

a first wavelength converting member on the first surface of the transparent board, the first wavelength converting member sealing the plurality of light emitting elements, the first wavelength converting member elongated in the first direction,

wherein the second surface of the transparent board faces the base, and

wherein the plurality of leads are tilted such that a distance between the end portions is larger than a distance between the lower portions at locations adjacent to the base.

2. The light emitting device according to claim 1, wherein the first wavelength member on the first surface of the transparent board is disposed between the end portions of the plurality of leads.

3. The light emitting device according to claim 1, wherein the first wavelength conversion member is a phosphor.

4. The light emitting device according to claim 3, wherein the phosphor includes a YAG group phosphor activated by europium, zinc sulfide coactivated by silver and aluminum, a nitride group phosphor including alkaline-earth silicon-nitride phosphor, or an oxynitride group phosphor including alkaline-earth silicon oxynitride phosphor.

5. The light emitting device according to claim 4, wherein the phosphor includes CaSi₂O₂N₂:

Eu, SrSi₂O₂N₂;

Eu, (Sr,Ca)₅(PO₄)₃Cl;

Eu, or (Ca,Sr)₂Si₅N₈;

Eu.

6. The light emitting device according to claim 1, wherein the first wavelength converting member contains a resin.

7. The light emitting device according to claim 1, wherein at least one of the plurality of light emitting elements is a nitride semiconductor.

8. The light emitting device according to claim 7, wherein at least one of the plurality of light emitting elements is made of In_xAl_yGa_1-x-yN (0≤

x, 0≤

y, x+y≤

1).

9. The light emitting device according to claim 1, wherein at least one of the plurality of light emitting elements has a light emission wavelength of 360 nm to 550 nm.

10. The light emitting device according to claim 1, wherein the plurality of light emitting elements is mounted on the first surface of the transparent board in a manner allowing the light emitted from the plurality of light emitting elements to pass both upwardly away from the first surface of the transparent board through the transparent member and downwardly through the second surface of the transparent board so as to output light both upwardly and downwardly from the light emitting device.

11. The light emitting device according to claim 1, wherein the plurality of light emitting elements is arranged in a plurality of lines.

12. The light emitting device according to claim 11, wherein lines of the plurality of lines are parallel.

13. The light emitting device according to claim 12, wherein the lines of the plurality of lines are collinear.

14. The light emitting device according to claim 1, wherein the light emitting device produces white light having high color rendering.

15. The light emitting device according to claim 1, wherein each of the plurality of light emitting elements is a light emitting diode or a laser diode.

16. The light emitting device according to claim 1, wherein the second surface of the transparent board is a non-smooth surface.

17. The light emitting device according to claim 1, further comprising a second wavelength converting member respectively arranged between the transparent board and at least one of the plurality of light emitting elements.

18. The light emitting device according to claim 1, wherein the plurality of light emitting elements are linearly arranged between the end portions of the leads.

19. A light emitting device comprising:

a transparent board having a first direction and a second direction which is perpendicular to the first direction, the transparent board being elongated longer in the first direction than that in the second direction and having a first surface on a first surface side thereof and a second surface on a second surface side thereof that is opposite to the first surface side;

a plurality of light emitting elements arranged in the first direction on the first surface side of the transparent board;

a transparent bulb housing the transparent board and the plurality of light emitting elements;

a base connected to the transparent bulb, the base having terminals and an upper end portion, the base being configured to be threadedly engaged with a socket for a conventional light bulb;

conductive members arranged at both side of the plurality of light emitting elements on the transparent board in the first direction;

a plurality of leads electrically connecting the plurality of light emitting elements to the base, the plurality of leads respectively having;

an end portion connected to a respective conductive member of the conductive members; and

a lower portion extending from the end portion toward the base; and

a first wavelength converting member on the first surface of the transparent board, the first wavelength converting member sealing the plurality of light emitting elements, the first wavelength converting member elongated in the first direction,

wherein the second surface of the transparent board faces the base, and

wherein the plurality of leads are tilted in the manner that a distance between the end portions is larger than a distance between the lower portions at locations adjacent to the upper end portion of the base.

20. The light emitting device according to claim 19, wherein the first wavelength member on the first surface of the transparent board is disposed between the end portions of the plurality of leads.

21. The light emitting device according to claim 19, wherein the plurality of light emitting elements are linearly arranged between the end portions of the leads.