LED DEVICES WITH REDUCED REFLECTION AND AN LED DISPLAY INCLUDING SAME

• US 20140346545A1
• Filed: 06/05/2014
• Published: 11/27/2014
• Est. Priority Date: 01/05/2012
• Status: Active Grant

• Current Assignee: Cree Huizhou Solid State Lighting Company Limited (Smart Global Holdings Incorporated)
• Original Assignee: Cree Huizhou Solid State Lighting Company Limited (Smart Global Holdings Incorporated)
• Inventors: CHAN, Chi Keung, FEI, Xiang
• Granted Patent: US 9,461,217 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• 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 2224/73265 Layer and wire connectors
• 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 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 33/58 Optical field-shaping elements

Abstract

LED devices are provided including an LED package including an LED and an optical element in an optical receiving relationship with the LED. The optical element has a higher light absorbing property at an exit surface away from the LED than at a bottom surface proximal to the LED. The optical element may include different epoxies, dye, and opaque particles. Methods for producing disclosed LED devices are also disclosed.

Claims

1. A light emitting diode (LED) package comprising:

an LED; and

an optical element in an optical receiving relationship with the LED, wherein the optical element has a higher light absorbing property at an exit surface away from the LED than at a bottom surface proximal to the LED.

2. The LED package of claim 1, wherein the optical element comprises opaque particles having a graded particle density, such that a particle density in proximity to the exit surface is greater than the particle density in proximity to the LED.

3. The LED package of claim 1, wherein the optical element comprises a semi-transparent portion comprising opaque particles, and wherein the exit surface has a rough exterior surface.

4. The LED package of claim 3, wherein the rough exterior surface has irregular patterns that scatter light originating from outside the LED package and freely transmit light emitted from the LED.

5. The LED package of claim 4, wherein the irregular patterns have a maximum height of less than about 2.0 um.

6. The LED package of claim 4, wherein the irregular patterns have a maximum height of less than about 1.5 um.

7. The LED package of claim 3, wherein the opaque particles have diameters less than about 0.03 mm.

8. The LED package of claim 7, wherein the semi-transparent portion further comprises epoxy A, epoxy B, and opaque particles.

9. The LED package of claim 8, wherein the epoxy A and the epoxy B have similar compositional weight and the opaque particles comprise less than about 0.03% of a total weight of the epoxy A and the epoxy B.

10. The LED package of claim 8, wherein the epoxy A and the epoxy B have similar compositional weight and the opaque particles comprise less than about 0.007% of a total weight of the epoxy A and the epoxy B.

11. The LED package of claim 8, wherein the epoxy A and the epoxy B have similar compositional weight and the opaque particles comprise less than about 0.003% of a total weight of the epoxy A and the epoxy B.

12. The LED package of claim 9, wherein the semi-transparent portion reduces a luminous intensity from the LED by less than about 10.0%.

13. The LED package of claim 12, wherein the semi-transparent portion reduces a luminous intensity from the LED by less than about 5.0%.

14. A light emitting diode (LED) package comprising:

an LED; and

an optical element in an optical receiving relationship with the LED, wherein the optical element comprises a transparent portion and a semi-transparent portion, and wherein the semi-transparent portion has a higher light absorbing property than the transparent portion.

15. The LED package of claim 14, wherein the semi-transparent portion comprises opaque particles having diameters less than about 0.03 mm.

16. The LED package of claim 14, wherein the semi-transparent portion has a profile thickness less than about 0.4 mm.

17. The LED package of claim 14, wherein the semi-transparent portion has an increasing light absorbing property along a light path emitted from the LED, and the semi-transparent portion has a thinner profile thickness than the transparent portion.

18. The LED package of claim 14, wherein the semi-transparent portion has a rough exterior surface away from the LED.

19. The LED package of claim 18, wherein the rough exterior surface has irregular patterns that scatter light from outside and freely transmit light emitted from the LED.

20. The LED package of claim 19, wherein the irregular patterns has a maximum height of less than about 2.0 um.

21. The LED package of claim 19, wherein the irregular patterns has a maximum height of less than about 1.5 um.

22. The LED package of claim 20, wherein the semi-transparent portion further comprises epoxy A, epoxy B, and opaque particles, the opaque particles comprise less than about 0.03% of a total weight of the epoxy A and the epoxy B.

23. The LED package of claim 20, wherein the semi-transparent portion further comprises epoxy A, epoxy B, and opaque particles, the opaque particles comprise less than about 0.007% of a total weight of the epoxy A and the epoxy B.

24. The LED package of claim 20, wherein the semi-transparent portion further comprises epoxy A, epoxy B, and opaque particles, the opaque particles comprise less than about 0.003% of a total weight of the epoxy A and the epoxy B.

25. The LED package of claim 22, wherein the semi-transparent portion reduces a luminous intensity from the LED by less than about 10.0%.

26. The LED package of claim 22, wherein the semi-transparent portion reduces a luminous intensity from the LED by less than about 5.0%.