Radiation emitter device having an integral micro-groove lens

• US 6,670,207 B1
• Filed: 02/19/2002
• Issued: 12/30/2003
• Est. Priority Date: 03/15/1999
• Status: Expired due to Term

• Current Assignee: Everlight Electronics Company Limited
• Original Assignee: Gentex Corporation
• Inventors: Roberts, John K.
• Primary Examiner(s): FOURSON III, GEORGE R
• Application Number:
  US10/078,906
• Time in Patent Office: 679 Days
• Field of Search: 438/26, 438/27, 438/28, 438/35, 438/FOR.416, 264/242.17, 257/E33.059
• US Class Current: 438/27
• CPC Class Codes: B60Q 1/2665 on rear-view mirrors lighting devices for vehicle interior on or for rear-view mirrors B60Q3/258
• CPC Class Codes: B60Q 1/2696 Mounting of devices using LEDs
• CPC Class Codes: B60Q 3/258 Rear-view mirrors
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: F21S 41/155 Surface emitters, e.g. organic light emitting diodes [OLED]
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/235 Light guides
• CPC Class Codes: F21V 5/02 of prismatic shape F21V5/04 takes precedence
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• 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 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/49562 for devices being provided for in H01L29/00
• CPC Class Codes: H01L 24/48 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 2924/00015 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed as prior art
• CPC Class Codes: H01L 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01077 : Iridium [Ir]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/1815 : Shape
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• 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 33/54 : 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: H01L 33/64 : Heat extraction or cooling elements
• CPC Class Codes: H01L 33/642 : characterized by the shape
• CPC Class Codes: H05B 45/40 : Details of LED load circuits
• CPC Class Codes: H10K 50/84 : Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/85 : Arrangements for extracting light from the devices
• CPC Class Codes: H10K 50/87 : Arrangements for heating or cooling
• CPC Class Codes: H10K 59/87 : Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 59/875 : Arrangements for extracting light from the devices
• CPC Class Codes: H10K 59/8794 : Arrangements for heating and cooling

Abstract

The radiation emitter device of the present invention includes at least two radiation emitters emitting radiation of different wavelengths, first and second electrical leads electrically coupled to at least one of the radiation emitters, and an encapsulant configured to encapsulate the radiation emitters and a portion of the first and second electrical leads. The encapsulant is further configured to have a surface defining an optical lens including a plurality of concentric circular grooves. The optical lens is preferably a divergent lens. Preferably, the lens is a multi-faceted Fresnel lens structure having a plurality of risers and Fresnel facets defining the plurality of concentric circular grooves. The radiation emitter device may further include a secondary reflective cup, preferably a parabolic or elliptical reflective cup, disposed proximate the encapsulant about the periphery of the Fresnel lens structure.

Claims

1. A discrete radiation emitter device comprising:

at least two radiation emitters emitting radiation of different wavelengths;

a leadframe including a heat extraction member in thermal contact with at least one of said radiation emitters, said leadframe further including first and second electrical leads electrically coupled to at least one of said radiation emitters; and

an encapsulant configured to encapsulate said radiation emitters and a portion of said first and second electrical leads, said heat extraction member extending out from said encapsulant to provide a first thermal path from at least one of said radiation emitters, said first thermal path being separate from a second thermal path provided by said first and second electrical leads, said encapsulant further configured to have a surface defining an optical lens including a plurality of concentric circular grooves, wherein said optical lens is a divergent lens;

and

wherein said first thermal path provided by said heat extraction member has a lower thermal resistance than said second thermal path provided by said electrical leads.

2. The radiation emitter device of claim 1, wherein said lens is a multi-faceted Fresnel lens structure having a plurality of risers and Fresnel facets defining the plurality of concentric circular grooves.

3. The radiation emitter device of claim 1, wherein said radiation emitters are LED chips.

17. The radiation emitter device of claim 1, where at least one of said radiation emitters is an LED chip.

4. A radiation emitter assembly comprising:

at least one discrete radiation emitter device comprising;

at least two radiation emitters emitting radiation of different wavelengths;

a leadframe including a heat extraction member in thermal contact with at least one of said radiation emitters, said leadframe further including first and second electrical leads electrically coupled to at least one of said radiation emitters; and

an encapsulant configured to encapsulate said radiation emitters and a portion of said first and second electrical leads, said heat extraction member extending out from said encapsulant to provide a first thermal path from at least one of said radiation emitters, said first thermal path being separate from a second thermal path provided by said first and second electrical leads, said encapsulant further configured to have a surface defining a divergent optical lens; and

a secondary reflective cup disposed proximate said divergent optical lens of said radiation emitter device;

and

wherein said first thermal path provided by said heat extraction member has a lower thermal resistance than said second thermal path provided by said electrical leads.

5. The radiation emitter assembly of claim 4, wherein said secondary reflective cup is positioned about the periphery of said divergent optical lens such that said reflective cup reflects radiation emitted from said divergent optical lens.

6. The radiation emitter assembly of claim 4, wherein said divergent optical lens includes a plurality of concentric circular grooves.

7. The radiation emitter assembly of claim 4, wherein said secondary reflective cup is parabolic.

8. The radiation emitter assembly of claim 4, wherein said secondary reflective cup is elliptical.

9. The radiation emitter assembly of claim 4 and further including a secondary lens disposed at an opposite end of said secondary reflective cup from said discrete radiation emitter device.

10. The radiation emitter assembly of claim 4, wherein said radiation emitter assembly is a vehicle lamp assembly, which further comprises a mounting mechanism for mounting the vehicle lamp assembly to a component of a vehicle.

11. A map lamp assembly for a vehicle rearview mirror, said map lamp assembly comprising:

at least one discrete radiation emitter device comprising;

at least two radiation emitters emitting radiation of different wavelengths;

a leadframe including a heat extraction member in thermal contact with at least one of said radiation emitters, said leadframe further including first and second electrical leads electrically coupled to at least one of said radiation emitters; and

an encapsulant configured to encapsulate said radiation emitters and a portion of said first and second electrical leads, said heat extraction member extending out from said encapsulant to provide a first thermal path from at least one of said radiation emitters, said first thermal path being separate from a second thermal path provided by said first and second electrical leads, said encapsulant further configured to have a surface defining a divergent optical lens; and

a secondary reflective cup disposed proximate said divergent optical lens of said radiation emitter device;

and

wherein said first thermal path provided by said heat extraction member has a lower thermal resistance than said second thermal path provided by said electrical leads.

12. The map lamp assembly of claim 11, wherein said secondary reflective cup is positioned about the periphery of said divergent optical lens such that said reflective cup reflects radiation emitted from said divergent optical lens.

13. The map lamp assembly of claim 11, wherein said divergent optical lens includes a plurality of concentric circular grooves.

14. The map lamp assembly of claim 11, wherein said secondary reflective cup is parabolic.

15. The map lamp assembly of claim 11, wherein said secondary reflective cup is elliptical.

16. The map lamp assembly of claim 11 and further including a secondary lens disposed at an opposite end of said secondary reflective cup from said discrete radiation emitter device.