Backlight unit and display apparatus including the same

Patent metadata

Field	Value
Publication number	US-9746709-B2
Application number	US-201514819842-A
Country	US
Kind code	B2
Filing date	Aug 6, 2015
Priority date	Feb 11, 2015
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Provided are a backlight unit and a display apparatus including the same. An optical lens of an optical unit has a shape asymmetrical with respect to a plane that bisectionally divides a center of an optical package. A plurality of reflectors each of which has an embossed or engraved shape are disposed on a top surface of the reflection sheet.

First claim

What is claimed is:

1. A backlight unit comprising:
an optical sheet;
a reflection sheet below the optical sheet, wherein the reflection sheet includes a reflection layer; and
at least one light source configured to emit light toward a space between the optical sheet and the reflection sheet, the at least one light source including a light source package on a surface and an optical lens over the light source package,
wherein the reflection sheet includes a plurality of reflectors extending from the reflection layer toward the optical sheet to reflect light from the light source package toward the optical sheet,
wherein each reflector includes:
an inclined surface that is inclined with respect to the reflection layer to reflect light from the light source package toward the optical sheet; and
a support surface,
wherein the plurality of reflectors includes a first reflector, second reflector, and a third reflector provided in a sequential order along the reflection layer, wherein the inclined surface of the third reflector steeper than the inclined surface of the second reflector, and the inclined surface of the second reflector is steeper than the inclined surface of the first reflector,
wherein the optical lens has an asymmetrical shape with respect to a place that bisectionally divides the light source package,
wherein the plane is parallel to the optical sheet or the reflection sheet, and
wherein the optical lens includes:
a first lens part having a first side and a first end; and
a second lens part having a second side and a second end, the second end of the second lens part being closer to the reflection sheet than the first end of the first lens part, wherein the second end of the second lens part is further from the surface than the first end of the first lens part.

2. The backlight unit according to claim 1 , wherein a distance between the third reflector and the second reflector is less than a distance between the second reflector and the first reflector.

3. The backlight unit according to claim 1 , wherein the support surface is a back surface, and wherein a height of the third reflector is greater than a height of the second reflector, and the height of the second reflector is greater than a height of the first reflector.

4. The backlight unit according to claim 3 , wherein the height of the first reflector is at least 50 nm.

5. The backlight unit according to claim 1 , wherein the reflector is smoothly rounded.

6. The backlight unit according to claim 1 , wherein the reflection sheet is curved between each of the plurality of reflectors and the reflection layer.

7. The backlight unit according to claim 1 , wherein the reflection sheet is formed of a white resin material.

8. A backlight unit comprising:
an optical sheet;
a reflection sheet below the optical sheet, wherein the reflection sheet includes a reflection layer; and
at least one light source configured to emit light toward a space between the optical sheet and the reflection sheet, the at least one light source including a light source package on a surface and an optical lens over the light source package,
wherein the reflection sheet includes a plurality of recesses to reflect light from the light source package toward the optical sheet,
wherein each recess includes:
an inclined surface that is inclined with respect to the reflection layer; and
a support surface connecting an end of the inclined surface to a surface of the reflection layer,
wherein the plurality of recesses includes a first recess, a second recess, and a third recess, wherein the inclined surface of the third recess is steeper than the inclined surface of the second recess, and the inclined surface of the second recess is steeper than the inclined surface of the first recess,
wherein the optical lens has an asymmetrical shape with respect to a plane that bisectionally divides the light source package,
wherein the plane is parallel to the optical sheet or the reflection sheet, and
wherein the optical lens includes:
a first lens part having a first side and a first end; and
a second lens part having a second side and a second end, the second end of the second lens part being closer to the reflection sheet than the first end of the first lens part, wherein the second end of the second lens part is further from the surface than the first end of the first lens part.

9. The backlight unit according to claim 8 , wherein the plurality of recesses have a same recessed depth.

10. The backlight unit according to claim 8 , wherein the reflection layer is formed of a transparent resin, and the reflection sheet includes a sheet base formed of a white resin.

11. The backlight unit according to claim 10 , wherein light from the light source package penetrates the reflection layer and is reflected at the sheet base toward the inclined surface of one of the recesses, and a first portion of the light at the inclined surface is directed toward the optical sheet, and a second portion of the light is directed toward the sheet base.

12. The backlight unit according to claim 10 , wherein the reflection layer has a thickness of at least 200 um, and each recess has a recessed depth of at least 50 um.

13. A display apparatus comprising:
a bottom cover including:
a bottom part; and
first and second side surface parts that are respectively bent upward from both ends of the bottom part;
a display panel on upper ends of the first and second side surface parts of the bottom cover; and
the backlight unit according to claim 1 , the backlight unit being between the bottom cover and the display panel.

14. The display apparatus according to claim 13 , wherein the light source is at the first side surface part to provide light towards the second side surface part.

15. The display apparatus according to claim 13 , wherein the reflection sheet includes:
a first end at a first point of the first side surface part; and
a second end at a second point of the second side surface part, wherein a contact portion of the reflection sheet contacts the bottom cover, and wherein a distance between the second point and the bottom cover is greater than a distance between the first point and the bottom cover.

16. The display apparatus according to claim 15 , wherein the reflection sheer is curved between the first end and the second end, and the contact portion of the reflection sheet is closer to the first side surface part than the second side surface part.

17. The backlight unit according to claim 1 , wherein the third reflector is located farther from the light source than the second reflector, and the second reflector is located farther from the light source than the first reflector.

18. The backlight unit according to claim 17 , wherein the inclined surface faces the light source.

Assignees

• Lg Electronics Inc

Inventors

• KIM Geunhwan
• Han Jongho
• Joung Juyoung
• Kee Wondo
• Kim Minho

Classifications

• G02F1/133606 Primary

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

• G02F1/133605

  including specially adapted reflectors · CPC title

• G02F1/133308

  Support structures for LCD panels, e.g. frames or bezels · CPC title

• G02B6/0096

  the lights guides being of the hollow type · CPC title

• G02B6/0058

  varying in density, size, shape or depth along the light guide · CPC title