LED package, backlight unit and illumination device including same, and liquid crystal display including backlight unit

Patent metadata

Field	Value
Publication number	US-10627672-B2
Application number	US-201615271902-A
Country	US
Kind code	B2
Filing date	Sep 21, 2016
Priority date	Sep 22, 2015
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A light emitting diode (LED) package includes: an LED; a stack structure including a light-scattering structure spaced apart from the LED, and a light conversion layer disposed on at least one surface selected from an inner surface and an outer surface of the light-scattering structure and configured to convert light emitted from the LED into white light, wherein the light conversion layer includes a semiconductor nanocrystal; and an organic barrier layer disposed on a surface of the light conversion layer.

First claim

What is claimed is:

1. A light emitting diode package comprising:
a light emitting diode;
a stack structure comprising,
a light-scattering structure spaced apart from the light emitting diode, and
a light conversion layer disposed on an outer surface of the light-scattering structure and configured to convert light emitted from the light emitting diode into white light, wherein the light conversion layer comprises a semiconductor nanocrystal;

an unoccupied space between the light-emitting diode and the stack structure; and
an organic barrier layer disposed on a surface of the light conversion layer,
wherein the light-scattering structure is directly adjacent to the space and the light-scattering structure does not comprise a semiconductor nanocrystal,
wherein refractive indexes of the light-scattering structure, the light conversion layer, and the organic barrier layer decrease sequentially as a distance between each layer increases from the light emitting diode, such that the refractive index of the light-scattering structure is greater than the refractive index of the light conversion layer, and the refractive index of the light conversion layer is greater than the refractive index of the barrier layer, and
wherein the organic barrier layer has an oxygen transmission rate of greater than or equal to about 10 −3 cubic centimeters per square meter per day and less than or equal to about 10 −1 cubic centimeters per square meter per day.

2. The light emitting diode package of claim 1 , wherein the light emitting diode is a blue light source or an ultraviolet light source.

3. The light emitting diode package of claim 1 , wherein the light-scattering structure has a structure in a shape of a lens.

4. The light emitting diode package of claim 3 , wherein the structure has a concave lens shape or a convex lens shape.

5. The light emitting diode package of claim 1 , wherein the light-scattering structure consists of the polymer, and the polymer is selected from polymethyl(meth)acrylate, polycarbonate, polyvinyl alcohol, an epoxy-containing polymer, a silicone polymer, or a combination thereof.

6. The light emitting diode package of claim 1 , wherein the light-scattering structure has transmittance of greater than or equal to about 80%.

7. The light emitting diode package of claim 1 , wherein the light-scattering structure consists of a polymer having a glass transition temperature of greater than or equal to about 85° C.

8. The light emitting diode package of claim 1 , wherein the light-scattering structure has a refractive index of greater than or equal to about 1.4.

9. The light emitting diode package of claim 1 , wherein the light-scattering structure has a concavo-convex shape.

10. The light emitting diode package of claim 1 , wherein the light-scattering structure is spaced apart from the LED by a distance of less than or equal to about 5 millimeters.

11. The light emitting diode package of claim 1 , wherein the light conversion layer comprises the semiconductor nanocrystal and a matrix.

12. The light emitting diode package of claim 11 , wherein the matrix comprises a material selected from a silicone resin, an epoxy resin, a thiol-ene polymer, a (meth)acrylate-polymer, silica, alumina, zinc oxide, zirconia, titania, and a combination thereof.

13. The light emitting diode package of claim 1 , wherein the semiconductor nanocrystal has a full width at half maximum of less than or equal to about 45 nanometers in a photoluminance wavelength spectrum.

14. The light emitting diode package of claim 1 , wherein the semiconductor nanocrystal is coated with a polymer comprising a carboxyl group or a salt thereof.

15. The light emitting diode package of claim 14 , wherein the polymer including a carboxyl group or a salt thereof is selected from poly(alkylene-co-acrylic acid), poly(alkylene-co-methacrylic acid), a salt thereof, or a mixture thereof.

16. The light emitting diode package of claim 1 , wherein the semiconductor nanocrystal is further coated with a polymer having a carboxylate anion group capable of binding to a surface of the semiconductor nanocrystal and a metal cation capable of binding the carboxylate anion group,
wherein a metal of the metal cation is different from a metal of the semiconductor nanocrystal.

17. The light emitting diode package of claim 1 , wherein the light conversion layer comprises a yellow semiconductor nanocrystal or a mixture of a red semiconductor nanocrystal and a green semiconductor nanocrystal.

18. The light emitting diode package of claim 1 , wherein the light conversion layer further comprises an inorganic oxide particle.

19. The light emitting diode package of claim 18 , wherein the inorganic oxide particle is selected from silica, alumina, zinc oxide, zirconia, titania, and a combination thereof.

20. The light emitting diode package of claim 1 , further comprising a transparent polymer filling a space inside of the light-scattering structure.

21. The light emitting diode package of claim 20 , wherein the LED package further includes a first inorganic barrier layer between the light conversion layer and the organic barrier layer.

22. The light emitting diode package of claim 20 , wherein the light emitting diode package further comprises an organic barrier layer or an inorganic barrier layer on the outer surface of the light-scattering structure.

23. The light emitting diode package of claim 20 , wherein the light emitting diode package further comprises a glass plate under the organic barrier layer.

24. The light emitting diode package of claim 1 , wherein the light emitting diode package further comprises a metal pattern on at least one of an outer surface of the organic barrier layer and the outer surface of the light conversion layer.

25. The light emitting diode package of claim 24 , wherein the metal pattern comprises a metal selected from aluminum, nickel, silver, gold, titanium, iron, copper, platinum, palladium, tungsten, and a combination thereof.

26. The light emitting diode package of claim 1 , wherein the light emitting diode package further comprises a first inorganic barrier layer between the organic barrier layer and the light conversion layer.

27. The light emitting diode package of claim 26 , wherein the first inorganic barrier layer comprises a material selected from an inorganic oxide, an inorganic polymer, an organic/inorganic hybrid polymer, a polymer comprising a first monomer having at least two thiol groups at a terminal end and a second monomer or oligomer comprising a siloxane and having at least two carbon-carbon unsaturated bonds at a terminal end, and a combination thereof.

28. The light emitting diode package of claim 1 , wherein the light emitting diode package further comprises a second inorganic barrier layer between the light-scattering structure and the light conversion layer.

29. The light emitting diode package of claim 28 , wherein the second inorganic barrier layer comprises at least one material selected from an inorganic oxide, an inorganic polymer, an organic/inorganic hybrid polymer, a polymer comprising a first monomer having at least two thiol groups at a terminal end and a second monomer or oligomer comprising siloxane and having at least two carbon-carbon unsaturated bonds at a terminal end, and a combination thereof.

30. The light emi

Assignees

• Samsung Electronics Co Ltd

Inventors

• Jang Eun Joo
• Kang Hyun A
• Jun Shin Ae
• Cho Oul

Classifications

• G02F1/133603 Primary

  with LEDs · CPC title

• C09K11/70

  containing phosphorus · CPC title

• H05B45/00

  Circuit arrangements for operating light-emitting diodes [LED] · CPC title

• G02B6/0073

  Light emitting diode [LED] · CPC title

• C09K11/883

  with zinc or cadmium · CPC title