LIGHT GUIDING FILM, DIRECT TYPE BACKLIGHT MODULE AND DISPLAY DEVICE

• US 20190324326A1
• Filed: 01/08/2019
• Published: 10/24/2019
• Est. Priority Date: 04/18/2018
• Status: Active Grant

• Current Assignee: Beijing BOE Optoelectronics Technology Co Ltd. (BOE Technology Group Co., Ltd.), BOE Technology Group Co., Ltd.
• Original Assignee: Beijing BOE Optoelectronics Technology Co Ltd. (BOE Technology Group Co., Ltd.), BOE Technology Group Co., Ltd.
• Inventors: Chen, Yinwei, Xiao, Liang, Tan, Yezhou, Cai, Jie
• Granted Patent: US 10,670,916 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses

Abstract

The present disclosure relates to the field of display technology, and provides a light guiding film. The light guiding film includes a plurality of prism bodies arranged as an array. Each of the plurality of prism bodies has a first surface and a second surface oppositely disposed. The first surface is a light exiting surface. A space is disposed between two adjacent prism bodies. The prism body is configured to refract light incident into the space to form refracted light, such that the refracted light is totally reflected in the prism body to form total reflection light.

Claims

1. A light guiding film, comprising:

a plurality of prism bodies arranged in array, and having a first surface and a second surface oppositely disposed;

wherein the first surface is a light exiting surface, and a respective space is disposed between two adjacent ones of the plurality of prism bodies, each of the plurality of prism bodies is configured to refract light incident into the respective space to form refracted light, such that the refracted light is totally reflected in each of the plurality of prism bodies to form total reflection light.

2. The light guiding film according to claim 1, wherein a cross-sectional of the respective space taken along a surface perpendicular to the second surface has a shape of an isosceles acute triangle.

3. The light guiding film of claim 2, wherein an apex angle of the isosceles acute triangle is greater than 0 degree and less than or equal to 20 degrees.

4. The light guiding film according to claim 1, wherein a cross-sectional of the respective space taken along a surface perpendicular to the second surface has a shape of an isosceles acute triangle, and an apex angle of the isosceles acute triangle is rounded.

5. The light guiding film according to claim 1, wherein a cross-sectional of the respective space taken along a surface perpendicular to the second surface has a shape of a pentagon, and wherein an apex angle of the pentagon is an acute angle and the pentagon has an axisymmetric structure along a bisector of the acute angle.

6. The light guiding film according to claim 5, wherein each of the plurality of prism bodies further comprises:

a convex portion disposed on the first surface and configured to totally reflect the light incident thereon.

7. The light guiding film according to claim 6, wherein the apex angle of the pentagon is greater than or equal to 30 degrees and less than 90 degrees, and the convex portion is located at a first position on the first surface, wherein the light refracted at a light incident surface of each of the plurality of prism bodies is incident at the first position.

8. The light guiding film according to claim 1, wherein the plurality of prism bodies, arranged as an array, are formed in an integrated structure.

9. The light guiding film according to claim 1, wherein each of the plurality of prism bodies further comprises:

a reflective dot layer disposed on the second surface and configured to reflect the total reflection light such that the total reflection light is emitted through the first surface.

10. The light guiding film according to claim 1, wherein the space is one or more of a pyramid shape, a conical shape, and a prism shape extending along the second surface.

11. A direct type backlight module, comprising:

a substrate;

a light source disposed on the substrate; and

a light guiding film disposed on the substrate, the light guiding film comprising a plurality of prism bodies arranged as an array, and having a first surface and a second surface oppositely disposed;

wherein the first surface is a light exiting surface, and a respective space is disposed between two adjacent one of the plurality of prism bodies, each of the plurality of prism bodies is configured to refract light incident into the respective space to form refracted light, such that the refracted light is totally reflected in each of the plurality of prism bodies to form total reflection light,

wherein the light source is located in the space.

12. The direct type backlight module according to claim 11, wherein a cross-sectional of the space taken along a surface perpendicular to the second surface has a shape of an isosceles acute triangle.

13. The direct type backlight module according to claim 11, wherein a cross-sectional of the space taken along a surface perpendicular to the second surface has a shape of an isosceles acute triangle, and an apex angle of the isosceles acute triangle is rounded.

14. The direct type backlight module according to claim 11, wherein a cross-sectional of the space taken along a surface perpendicular to the second surface has a shape of a pentagon, and wherein an apex angle of the pentagon is an acute angle and the pentagon has an axisymmetric structure along a bisector of the acute angle.

15. The direct type backlight module according to claim 14, wherein each of the plurality prism bodies further comprises:

a convex portion disposed on the first surface and configured to totally reflect the light incident thereon.

16. The direct type backlight module according to claim 15, wherein the apex angle of the pentagon is greater than or equal to 30 degrees and less than 90 degrees, and the convex portion is located at a first position on the first surface, wherein the light refracted at a light incident surface of each of the plurality of prism bodies is incident on the first position.

17. The direct type backlight module according to claim 11, wherein each of the plurality of prism bodies further comprises:

a reflective dot layer disposed on the second surface and configured to reflect the total reflection light such that the total reflection light is emitted through the first surface.

18. The direct type backlight module according to claim 17, wherein the reflective dot layer is bonded to the substrate.

19. The direct type backlight module according to claim 11, wherein the direct type backlight module comprises:

a first brightness enhancement film disposed on the first surface;

a diffusion film disposed on a side of the first brightness enhancement film away from the light guiding film; and

a second brightness enhancement film disposed between the first brightness enhancement film and the diffusion film;

wherein a second prism body on the second brightness enhancement film and a first prism body on the first brightness enhancement film are disposed perpendicular to each other.

20. A display device, comprising:

a direct type backlight module according to claim 11.