LIGHT EMITTING DEVICE

• US 20130193462A1
• Filed: 03/13/2013
• Published: 08/01/2013
• Est. Priority Date: 01/22/2010
• Status: Active Grant

• Current Assignee: Heavy Duty Lighting LLC (Ni, Wang & Massand, PLLC)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ishizaki, Shinya, Agatani, Makoto, Nada, Tomokazu, Hata, Toshio
• Granted Patent: US 8,723,195 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• 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 9/238 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 5/048 the lens being a simple lens adapted to cooperate with a point-like source for emitting mainly in one direction and having an axis coincident with the main light transmission direction, e.g. convergent or divergent lenses, plano-concave or plano-convex lenses
• CPC Class Codes: F21V 5/10 comprising photoluminescent material
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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 2924/3011 Impedance
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/483 Containers
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• 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 33/52 Encapsulations
• 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 33/60 : Reflective elements
• 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

Abstract

A light emitting device includes: a ceramic substrate; a plurality of LED chips; a printed resistor(s) connected in parallel with the plurality of LED chips; a dam resin made of a resin having a low optical transmittance; a fluorescent-material-containing resin layer; and an anode-side electrode and a cathode-side electrode, (a) which are provided on a primary surface of the ceramic substrate so as to face each other along a first direction on the primary surface and (b) which are disposed below at least one of the dam resin and the fluorescent-material-containing resin layer. With the configuration in which a plurality of LEDs, which are connected in a series-parallel connection, are provided on a substrate, it is possible to provide a light emitting device which can achieve restraining of luminance unevenness and an improvement in luminous efficiency.

Claims

1. A light emitting device comprising:

a substrate having a rectangular outer shape in a top view;

a plurality of light emitting elements positioned around a center of a primary surface of the substrate, the plurality of light emitting elements being LED chips;

an electrode wiring pattern including a first light emitting element connection electrode and a second light emitting element connection electrode, the first light emitting element connection electrode and the second light emitting element connection electrode being an anode electrode and a cathode electrode, respectively; and

an anode-side electrode land and a cathode-side electrode land which are electrodes connected to an external voltage supply of said light emitting device, the anode-side electrode land and the cathode-side electrode land being provided near corners of the primary surface of the substrate, and

the electrode wiring pattern being a wiring pattern provided between the anode-side electrode land and the cathode-side electrode land so as to electrically connect the plurality of light emitting elements to the anode-side electrode land and the cathode-side electrode land.

2. The light emitting device as set forth in claim 1, wherein:

the cathode-side electrode land is provided near a corner of the primary surface of the substrate, which corner is diagonally opposite a corner where the anode-side electrode land is provided.

3. The light emitting device as set forth in claim 1, wherein:

the anode-side electrode land and the cathode-side electrode land are disposed diagonally on the primary surface of the substrate.

4. a light emitting device as set forth in claim 1, further comprising:

a resin frame which is provided annularly so as to surround a mounting area in which the plurality of light emitting elements are provided.

5. A light emitting device as set forth in claim 4, further comprising:

a wire for electrically connecting the plurality of light emitting elements with each other, and

a fluorescent-material-containing resin layer provided adjacent to an inner side of the resin frame so as to cover the plurality of light emitting elements and the wire.

6. The light emitting device as set forth in claim 5, wherein:

The fluorescent-material-containing resin layer is provided along a shape of the resin frame so as to have a circular shape in the top view.

7. The light emitting device as set forth in claim 4, wherein:

the resin frame is made of resin that has light reflectivity.

8. A light emitting device as set forth in claim 1, further comprising:

at least one of a protective element and a Zener diode, which is connected in parallel with the plurality of light emitting elements.

9. The light emitting device as set forth in claim 1, wherein:

said light emitting device includes no protective element connected in parallel with the plurality of light emitting elements.