Optical lens module and backlight unit

Patent metadata

Field	Value
Publication number	US-2015029692-A1
Application number	US-201314107727-A
Country	US
Kind code	A1
Filing date	Dec 16, 2013
Priority date	Jul 24, 2013
Publication date	Jan 29, 2015
Grant date	—

Abstract

A backlight unit which provides light to a liquid crystal display panel of a liquid crystal display. The backlight unit includes an optical lens module including an optical lens disposed above a point light source and configured to refract light output from the point light source, and a reflective polarization layer disposed directly on the optical lens and configured to separate polarization components of the light to transmit one polarization component and reflect another polarization component.

First claim

What is claimed is:

1 . An optical lens module, comprising:
a point light source; an optical lens disposed above the point light source and configured to refract light output from the point light source; and a reflective polarization layer disposed on the optical lens and configured to transmit a first polarization component of the refracted light and reflect a second polarization component of the refracted light.

2 . The optical lens module of claim 1 , wherein the reflective polarization layer is directly formed on an upper surface of the optical lens.

3 . The optical lens module of claim 1 , wherein the reflective polarization layer is attached to an upper surface of the optical lens.

4 . The optical lens module of claim 1 , wherein the reflective polarization layer is spaced apart from an upper surface of the optical lens.

5 . The optical lens module of claim 1 , wherein the reflective polarization layer entirely covers an upper surface of the optical lens.

6 . The optical lens module of claim 1 , wherein the reflective polarization layer comprises a multi-layered optical film structure having refractive anisotropy.

7 . The optical lens module of claim 1 , wherein the reflective polarization layer comprises a wire grid structure.

8 . The optical lens module of claim 1 , wherein:
the reflective polarization layer comprises a cholesteric liquid crystal layer, and the cholesteric liquid crystal has refractive indices that differ in different directions.

9 . A direct-type backlight unit, comprising:
a point light source mounted on a substrate; an optical lens disposed above the point light source and configured to refract light output from the point light source; a reflective polarization layer disposed on the optical lens and configured to transmit a first polarization component of the refracted light and to reflect a second polarization component of the refracted light; and a reflective layer disposed below the optical lens and configured to reflect the second polarization component.

10 . The direct-type backlight unit of claim 9 , wherein the reflective polarization layer is formed directly on an upper surface of the optical lens.

11 . The direct-type backlight unit of claim 9 , wherein the reflective polarization layer is attached to an upper surface of the optical lens.

12 . The direct-type backlight unit of claim 9 , wherein the reflective polarization layer is spaced apart from an upper surface of the optical lens.

13 . The direct-type backlight unit of claim 9 , wherein the reflective polarization layer entirely covers an upper surface of the optical lens.

14 . The direct-type backlight unit of claim 9 , wherein the reflective layer has a reflectance of at least 95%.

15 . The direct-type backlight unit of claim 9 , wherein the reflective layer is attached to an upper surface of the substrate.

16 . The direct-type backlight unit of claim 9 , wherein the reflective layer is formed on a diffuse reflective sheet.

17 . The direct-type backlight unit of claim 9 , wherein the reflective layer has an area that is equal to or greater than the area of the optical lens.

18 . The direct-type backlight unit of claim 9 , further comprising at least one isotropic optical sheet disposed above the reflective polarization layer.

19 . The direct-type backlight unit of claim 18 , wherein the isotropic optical sheet comprises an isotropic diffuser sheet and an isotropic prism sheet.

20 . The direct-type backlight unit of claim 19 , wherein the optical sheet comprises an isotropic material having reflective indexes in x-axis, y-axis, and z-axis directions which differ from each other by 0.1 or less.

21 . The direct-type backlight unit of claim 9 , wherein the point light source comprises at least one light emitting diode (LED).

Assignees

• Samsung Display Co Ltd

Inventors

• Chung Seung Hwan
• Yeom Dong-Yeol
• Kim Joong Hyun
• Bang Jin Sook
• Ha Sang Woo

Classifications

• G02B5/3016

  involving passive liquid crystal elements (optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528) · CPC title

• F21V13/04 Primary

  the elements being reflectors and refractors {(for vehicle rear lights F21S43/40)} · CPC title

• G02F1/133606 Primary

  including a specially adapted diffusing, scattering or light controlling members · CPC title

• G02F1/133603

  with LEDs · CPC title

• G02F1/133607

  the light controlling member including light directing or refracting elements, e.g. prisms or lenses · CPC title