Backlight module including privacy structure with triangular prism structure and display apparatus including the same

Patent metadata

Field	Value
Publication number	US-12158641-B2
Application number	US-202117781188-A
Country	US
Kind code	B2
Filing date	Apr 21, 2021
Priority date	Apr 21, 2021
Publication date	Dec 3, 2024
Grant date	Dec 3, 2024

Abstract

A backlight module, including: a surface light source; a first light guide plate laminated with the surface light source in a thickness direction, wherein the first light guide plate is on a light-exiting side of the surface light source, and a side of the first light guide plate proximal to the surface light source comprises a plurality of first networks; and a first light source on a side surface of the first light guide plate, in which an orthographic projection of the first light source onto a plane, where a light-exiting surface of the surface light source is located, does not overlap with that of the first light guide plate onto the plane.

First claim

What is claimed is:

1. A backlight module, comprising:
a surface light source;
a first light guide plate laminated with the surface light source in a thickness direction, wherein the first light guide plate is on a light-exiting side of the surface light source, and a side of the first light guide plate proximal to the surface light source comprises a plurality of first prism structures; and
a first light source on a side surface of the first light guide plate, wherein an orthographic projection of the first light source onto a plane, where a light-exiting surface of the surface light source is located, does not overlap with that of the first light guide plate onto the plane;
wherein the surface light source is a collimation surface light source, the collimation surface light source comprises a privacy structure and a second light guide plate that are laminated in the thickness direction;
the second light guide plate is on a side of the privacy structure distal from the first light guide plate, and a side of the second light guide plate distal from the privacy structure comprises a plurality of second prism structures; and
the collimation surface light source further comprises a second light source on a side surface of the second light guide plate, and an orthographic projection of the second light source onto a plane, where a light-exiting surface of the collimation surface light source is located, does not overlap with that of the second light guide plate onto the plane.

2. The backlight module according to claim 1 , wherein
the first light source is a strip-shaped light source;
the first prism structure is of a prism structure, and a length direction of the first prism structure is parallel to an extending direction of a light source strip of the first light source; and
the first prism structure is of a triangular prism structure; the first prism structure comprises a first side surface in contact with the first light guide plate, and a second side surface and a third side surface which are connected to the first side surface; a first angle exists between the first side surface and the second side surface; a second angle exists between the first side surface and the third side surface; and a third angle exists between the second side surface and the third side surface.

3. The backlight module according to claim 2 , wherein a width of the first side surface in the length direction of the first prism structure ranges from 35 μm to 100 μm, and a width of the first side surface in a direction perpendicular to the length direction of the first prism structure ranges from 20 μm to 100 μm.

4. The backlight module according to claim 2 , wherein the first angle ranges from 20° to 70°, and the second angle is less than or equal to 20°.

5. The backlight module according to claim 1 , wherein
the privacy structure comprises a first substrate, and a plurality of strip-shaped first prisms on the first substrate, and the plurality of first prisms are on a side of the first substrate proximal to the second light guide plate; and
the second light source is a strip-shaped light source, and an extending direction of a light source strip of the second light source is the same as that of the light source strip of the first light source; and
length directions of the plurality of first prisms are parallel to the extending direction of the light source strip of the second light source.

6. The backlight module according to claim 5 , wherein
the first prism is of a triangular prism structure, and comprises a fourth side surface in contact with the first substrate, and a fifth side surface and a sixth side surface which are connected to the fourth side surface; and
a fourth angle between the fourth side surface and the fifth side surface is greater than or equal to a fifth angle between the fourth side surface and the sixth side surface, and the fourth side surface of the first prism is closer to the second light source than the fifth side surface.

7. The backlight module according to claim 6 , wherein the fourth angle ranges from 45° to 90°, and the fifth angle ranges from 45° to 70°.

8. The backlight module according to claim 6 , wherein
the fourth angle ranges from 60° to 72°, and the fifth angle ranges from 53° to 57°.

9. The backlight module according to claim 5 , wherein
the second prism structure is of a triangular prism structure, and a length direction of the second prism structure is parallel to the extending direction of the light source strip of the second light source;
the second prism structure comprises a seventh side surface in contact with the second light guide plate, and an eighth side surface and a ninth side surface which are connected to the seventh side surface; and
a seventh angle exists between the seventh side surface and the eighth side surface, an eighth angle exists between the seventh side surface and the ninth side surface, and a ninth angle exists between the eighth side surface and the ninth side surface.

10. The backlight module according to claim 9 , wherein
a width of the seventh side surface in the length direction of the second prism structure ranges from 35 μm to 100 μm, and a width of the seventh side surface in a direction perpendicular to the length direction of the second prism structure ranges from 20 μm to 100 μm.

11. The backlight module according to claim 9 , wherein
the seventh angle is greater than the eighth angle, and the eighth side surface of the second prism structure is closer to the second light source than the ninth side surface.

12. The backlight module according to claim 11 , wherein
the seventh angle ranges from 10° to 90°, and the eighth angle is less than or equal to 30°.

13. The backlight module according to claim 12 , wherein
the seventh angle ranges from 26° to 30°, and the eighth angle is less than or equal to 5°.

14. The backlight module according to claim 9 , wherein
a chamfer exists at the ninth angle between the eighth side surface and the ninth side surface, and the chamfer is a circular arc with a radius less than or equal to 30 μm.

15. The backlight module according to claim 14 , wherein the radius of the circular arc is less than or equal to 5 μm.

16. The backlight module according to claim 1 , wherein
the collimation surface light source further comprises a reflector on a side of the second light guide plate distal from the privacy structure; and
the collimation surface light source further comprises a second substrate between the second light guide plate and the reflector, and a plurality of strip-shaped second prisms on the second substrate, the second prisms are on a side of the second substrate proximal to the second light guide plate, and length directions of the plurality of second prisms are perpendicular to the extending direction of the light source strip of the second light source.

17. The backlight module according to claim 1 , wherein
the collimation surface light source further comprises a reflector on a side of the second light guide plate distal from the privacy structure; and
a side of the first light guide plate distal from the plurality of first prism structures comprises a plurality of strip-shaped third prisms, and/or a side of the second light guide plate distal from the plurality of second prism structures comprises a plurality of strip-shaped fourth prisms; and
length directions of the plurality of third prisms and length directions of the plurality of fourth prisms are perpendicular to the extending direction of the light source strip of the second light source.

Assignees

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

Inventors

• Zhu Heling
• Zhai Yue
• Sang Jian
• Han Rui
• Cui Dong
• Zhang Zhipeng

Classifications

• G02B6/0088

  of the light guide or other optical sheets in the package · CPC title

• 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

• G02B6/0055

  Reflecting element, sheet or layer · CPC title

• G02B6/0053

  Prismatic sheet or layer; Brightness enhancement element, sheet or layer · CPC title