Light emitting device package with frame and optically transmissive element

• US 7,906,794 B2
• Filed: 07/04/2007
• Issued: 03/15/2011
• Est. Priority Date: 07/05/2006
• Status: Expired due to Fees

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Schick, Philippe, Speier, Ingo, Harrah, Shane
• Primary Examiner(s): Vu; Hung
• Assistant Examiner(s): Webb; Vernon P
• Application Number:
  US11/773,426
• Publication Number:
  US 20080054288A1
• Time in Patent Office: 1,350 Days
• Field of Search: 257/98, 257/99, 257/100, 257/434, 257/E23.066, 257/E23.087
• US Class Current: 257/99
• 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 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements

Abstract

The present invention provides a lighting device package with one or more light-emitting elements operatively coupled to a substrate and a frame disposed at least in part around the one or more light-emitting elements. The frame and substrate define a cavity in which the one or more light-emitting elements are positioned, wherein this cavity can be substantially enclosed by an optically transmissive system. At least a portion of the cavity can be filled with an encapsulation material. The frame defines one or more passageways, wherein each passageway interconnects the cavity with the outside through an outside port. For example, the outside port can be accessible from the ambient when the lighting device package is in an assembled state, thereby enabling fluidic movement of the encapsulation material into and/or out of the cavity.

Claims

1. A lighting device package comprising:

a) a substrate;

b) a frame disposed on the substrate and having at least one passageway defined therein;

c) one or more light-emitting elements operatively disposed within the cavity; and

d) an optically transmissive system disposed on the frame and optically coupled to the one or more light-emitting elements;

wherein the frame has an inside surface that extends from a bottom surface of the optically transmissive system to a top surface of the substrate, and wherein the inside surface of the frame together with the bottom surface of the optically transmissive system and the top surface of the substrate define a cavity,

wherein the cavity is at least in part filled with a light transmissive encapsulation material,

wherein the passageway defined in the frame extends through the frame from the cavity to an associated outside port provided on a surface of the frame facing away from the substrate, and

wherein the passageway enables fluidic movement of the encapsulation material between the cavity and the associated outside port.

2. The lighting device package according to claim 1, wherein the inner surface is optically reflective.

3. The lighting device package according to claim 2, wherein the inner surface is coated with a specular reflective material.

4. The lighting device package according to claim 2, wherein the encapsulation material has a first index of refraction and the inner surface has a second index of refraction which is lower than the first index of refraction.

5. The lighting device package according to claim 2, wherein the inner surface has a surface shape selected from the group comprising;

ellipsoid, paraboloid and polyhedral.

6. The lighting device package according to claim 1, wherein the frame comprises a support structure configured to support and mechanically retain the optically transmissive system in a desired location.

7. The lighting device package according to claim 1, wherein the frame and the optically transmissive system are integrally formed.

8. The lighting device package according to claim 7, wherein the frame is formed from a first material and the optically transmissive system is formed from a second material.

9. The lighting device package according to claim 1, wherein the frame comprises two or more attachment devices configured to mechanically interconnect with respective mating attachment regions associated with the substrate.

10. The lighting device package according to claim 1, wherein the frame is electrically isolated from the substrate.

11. The lighting device package according to claim 1, wherein the frame and the substrate are integrally formed.

12. The lighting device package according to claim 1, wherein the passageway is configured to have a shape selected from the group comprising:

linear, curvilinear, segmented linear and segmented curvilinear.

13. The lighting device package according to claim 1, wherein the passageway has a cross section selected from the group comprising:

circular, square, rectangular, elliptical, oval and octagonal.

14. The lighting device package according to claim 1, wherein the passageway has a cross section and a length, wherein the cross section varies along the length so as to have a narrower cross-section where the passageway interfaces with the cavity and a greater cross-section where the passageway interfaces with the outside port.

15. The lighting device package according to claim 1, wherein the frame defines a second passageway fluidically coupling the cavity to a second associated outside port, wherein one or more of the two passageways are configured to enable gas to escape from the cavity.

16. The lighting device package according to claim 1, wherein the inner surface of the frame forms an angle of about 135 degrees with the top surface of the substrate.

17. The lighting device package of claim 1, wherein the encapsulation material has a first index of refraction and the one or more light-emitting elements have a second index of refraction which is greater than the first index of refraction.

18. The lighting device package of claim 1, wherein the encapsulation material has a first index of refraction and the optically transmissive system has a second index of refraction which is not less than the first index of refraction.

19. The lighting device package of claim 1, wherein the inner surface has mixed diffuse and specular reflective characteristics.

20. A lighting device package comprising:

a) a substrate;

b) a frame disposed on the substrate and defining a cavity, the frame comprising one or more passageways defined therein, each of said one or more passageways fluidically coupling the cavity to an associated outside port;

c) one or more light-emitting elements operatively disposed within the cavity; and

d) an optically transmissive system disposed on the frame and optically coupled to the one or more light-emitting elements;

wherein the cavity is at least in part filled with a light transmissive encapsulation material and wherein said one or more passageways enable fluidic movement of the encapsulation material,

wherein the frame includes an inner surface facing the cavity, wherein the inner surface is optically reflective, and

wherein the inner surface has mixed diffuse and specular reflective characteristics.