Backlight assembly and display apparatus

Patent metadata

Field	Value
Publication number	US-12189166-B2
Application number	US-202218015723-A
Country	US
Kind code	B2
Filing date	Feb 14, 2022
Priority date	Feb 14, 2022
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

Disclosed is a backlight assembly, including first and second light guide plates, and first and second light sources; light emitted by the first light source can be emitted from a surface of the first light guide plate facing the second light guide plate at a first set emitting angle, after being incident into the first light guide plate and reflected by a plurality of first microstructures disposed on a surface of the first light guide plate facing away from the second light guide plate; light emitted by the second light source can be emitted from a surface of the second light guide plate facing away from the first light guide plate at a second set emitting angle, after being incident into the second light guide plate and reflected by a plurality of second microstructures disposed on a surface of the second light guide plate facing the first light guide plate.

First claim

The invention claimed is:

1. A backlight assembly, comprising a first light guide plate and a second light guide plate disposed in parallel and opposite to each other, a first light source disposed on a side of the first light guide plate, and a second light source disposed on a side of the second light guide plate, wherein the first light source and the second light source are located on opposite sides of the backlight assembly, and the second light guide plate is disposed on a light emitting side of the first light guide plate;
a plurality of first microstructures are disposed on a surface of the first light guide plate facing away from the second light guide plate, and light emitted by the first light source is able to be emitted from a surface of the first light guide plate facing the second light guide plate at a first set emitting angle, after being incident into the first light guide plate and reflected by the plurality of first microstructures;
a plurality of second microstructures are disposed on a surface of the second light guide plate facing the first light guide plate, and light emitted by the second light source is able to be emitted from a surface of the second light guide plate facing away from the first light guide plate at a second set emitting angle, after being incident into the second light guide plate and reflected by the plurality of second microstructures;
taking a plane perpendicular to a light emitting surface of the backlight assembly as a reference plane, in the reference plane, the first set emitting angle is biased to one side compared with a front viewing angle direction of the light emitting surface of the backlight assembly, and the second set emitting angle is biased to the other side compared with the front viewing angle direction of the light emitting surface of the backlight assembly;
the first light source and the second light source are under a same current, and a luminous intensity of the first light source is greater than a luminous intensity of the second light source.

2. The backlight assembly according to claim 1 , wherein light emitted by the first light source is incident into the first light guide plate and is totally reflected at a position where a first microstructure is not disposed and is then incident into the first microstructures, and the light incident into the first microstructures is able to be totally reflected at the first microstructures, and then emitted from the surface of the first light guide plate facing the second light guide plate at the first set emitting angle;
or/and, light emitted by the second light source is incident into the second light guide plate and is totally reflected at a position where a second microstructure is not disposed and is then incident into the second microstructures, and the light incident into the second microstructures is able to be totally reflected at the second microstructures, and then emitted from the surface of the second light guide plate facing away from the first light guide plate at the second set emitting angle.

3. The backlight assembly according to claim 1 , wherein a first microstructure is a wedge-shaped protrusion having a triangular cross section; or a first microstructure is a V-shaped groove.

4. The backlight assembly according to claim 3 , wherein the first microstructure is a wedge-shaped protrusion having a triangular cross section; the first microstructure comprises a first surface away from the first light source and a second surface close to the first light source, an acute angle between the first surface and the surface of the first light guide plate facing away from the second light guide plate is α,and an acute angle between the second surface and the surface of the first light guide plate facing away from the second light guide plate is β1, wherein α1>β1; and after the light emitted by the first light source is incident into the first light guide plate, the light is able to be totally reflected on the second surface of the first microstructure.

5. The backlight assembly according to claim 3 , wherein the first microstructure is a V-shaped groove; the first microstructure comprises a first surface away from the first light source and a second surface close to the first light source, an acute angle between the first surface and the surface of the first light guide plate facing away from the second light guide plate is α1, and an acute angle between the second surface and the surface of the first light guide plate facing away from the second light guide plate is β1, wherein α1<β1;
and after the light emitted by the first light source is incident into the first light guide plate, the light is able to be totally reflected on the first surface of the first microstructure.

6. The backlight assembly according to claim 1 , wherein a second microstructure is a wedge-shaped protrusion having a triangular cross section; or a second microstructure is a V-shaped groove.

7. The backlight assembly according to claim 6 , wherein the second microstructure is a wedge-shaped protrusion having a triangular cross section, the second microstructure comprises a first surface away from the second light source and a second surface close to the second light source, an acute angle between the first surface and the surface of the second light guide plate facing the first light guide plate is α,and an acute angle between the second surface and the surface of the second light guide plate facing the first light guide plate is β2, wherein α2>β2; and after the light emitted by the second light source is incident into the second light guide plate, the light is able to be totally reflected on the second surface of the second microstructure.

8. The backlight assembly according to claim 6 , wherein the second microstructure is a V-shaped groove, the second microstructure comprises a first surface away from the second light source and a second surface close to the second light source, an acute angle between the first surface and the surface of the second light guide plate facing the first light guide plate is α2, and an acute angle between the second surface and the surface of the second light guide plate facing the first light guide plate is β2, wherein α2<β2; and after the light emitted by the second light source is incident into the second light guide plate, the light is able to be totally reflected on the first surface of the second microstructure.

9. The backlight assembly according to claim 1 , wherein an arrangement density of the first microstructures gradually increases along a direction of the first light guide plate away from the first light source;
or/and, an arrangement density of the second microstructures gradually increases along a direction of the second light guide plate away from the second light source.

10. The backlight assembly according to claim 1 , wherein sizes of the first microstructures gradually increase along a direction of the first light guide plate away from the first light source;
or/and, sizes of the second microstructures gradually increase along a direction of the second light guide plate away from the second light source.

11. The backlight assembly according to claim 1 , wherein the plurality of first microstructures are randomly arranged or regularly arranged on the first light guide plate;
or/and, the plurality of second microstructures are randomly arranged or regularly arranged on the second light guide plate.

12. The backlight assembly according to claim 1 , wherein a numerical value of the first set emitting angle is taken as a positive value, and a numerical value of the second set emitting angle is taken as a negative value; absolute values of the first se

Assignees

• Beijing Boe Display Tech Co
• Boe Technology Group Co Ltd

Inventors

• Qi yongle
• Han Rui
• Ma Qing
• Yoon Daekeun
• Cui Dong
• Zhang Zhipeng
• Zhu Yuanyuan
• Chi Weining
• Wang Fengping
• Leng Shouyang
• Li Wenyang
• Zhai Yue

Classifications

• G02B6/0076

  Stacked arrangements of multiple light guides of the same or different cross-sectional area · CPC title

• G02B6/0068

  Arrangements of plural sources, e.g. multi-colour light sources · CPC title

• G02B6/0058

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

• G02F1/1336

  Illuminating devices · CPC title

• G02B6/004 Primary

  Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles · CPC title