Backlight module and display device

Patent metadata

Field	Value
Publication number	US-11762235-B2
Application number	US-202017265061-A
Country	US
Kind code	B2
Filing date	Mar 30, 2020
Priority date	Mar 30, 2020
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A backlight module and a display device are disclosed. The backlight module includes a light emitting element array including a plurality of light emitting elements that emit blue light; a quantum dot film disposed on a light-emergent side of the light emitting element array and having a middle area and an edge area, the edge area surrounding the middle area; and a light conversion layer disposed on the light-emergent side of the light emitting element array, wherein an orthographic projection of the light conversion layer on the quantum dot film is located in the edge area of the quantum dot film, a material of the light conversion layer includes a first light conversion material configured to emit red light under excitation of light from the light emitting element and a second light conversion material configured to emit green light under excitation of light from the light emitting element.

First claim

The invention claimed is:

1. A backlight module, comprising:
a light emitting element array comprising a plurality of light emitting elements that emit blue light;
a quantum dot film disposed on a light-emergent side of the light emitting element array and having a middle area and an edge area, the edge area surrounding the middle area; and
a light conversion layer disposed on the light-emergent side of the light emitting element array, wherein an orthographic projection of the light conversion layer on the quantum dot film is in the edge area of the quantum dot film, a material of the light conversion layer comprises a first light conversion material configured to emit red light under excitation of light from the light emitting element and a second light conversion material configured to emit green light under excitation of light from the light emitting element,
wherein the light conversion layer comprises a plurality of light conversion units spaced apart from each other, a material of each of the plurality of light conversion units comprises the first light conversion material and the second light conversion material, and
a distribution density of the plurality of light conversion units is gradually increased along a direction from a center to an edge of the quantum dot film.

2. The backlight module of claim 1 , wherein a dimension of each of the plurality of light conversion unit in a width direction of the quantum dot film are both between 5 μm and 100 μm; and a thickness of the light conversion unit is between 4 μm and 30 μm.

3. The backlight module of claim 1 , wherein the plurality of light conversion units are formed by screen printing.

4. The backlight module of claim 1 , wherein the orthographic projection of the light conversion layer on the quantum dot film completely covers the edge area of the quantum dot film.

5. The backlight module of claim 1 , wherein both the first light conversion material and the second light conversion material are quantum dot materials; or
both the first light conversion material and the second light conversion material are phosphor materials.

6. The backlight module of claim 1 , wherein a distance between any two adjacent light emitting elements is between 1 mm and 1.5 mm, both a length and a width of each light emitting element are between 100 μm and 500 μm, a light emitting angle of each light emitting element is between 130° and 150°, a width of the edge area of the quantum dot film is between 3 mm and 5 mm, and the orthographic projection of the light conversion layer on the quantum dot film is in contact with each side edge of the middle area and in contact with each side edge of the quantum dot film.

7. The backlight module of claim 1 , wherein the quantum dot film comprises: a first barrier film layer, a second barrier film layer and a quantum dot layer between the first barrier film layer and the second barrier film layer, and a material of the quantum dot layer comprises a red quantum dot material configured to emit red light under excitation of light from the light emitting element and a green quantum dot material configured to emit green light under excitation of light from the light emitting element.

8. The backlight module of claim 1 , wherein the light emitting element is a light emitting diode.

9. A display device comprising: a backlight module and a liquid crystal display panel on a light-emergent side of the backlight module, wherein the backlight module is the backlight module of claim 1 .

10. The display device of claim 9 , wherein the liquid crystal display panel comprises: a liquid crystal cell and a polarizer between the liquid crystal cell and the backlight module,
the backlight module further comprises:
a diffuser on the light-emergent side of the light emitting element array; and
a prism sheet on a side of the quantum dot film away from the light emitting element array, the diffuser being between the light emitting element array and the prism sheet;
wherein the light conversion layer is on any one of the polarizer, the diffuser, the quantum dot film, and the prism sheet.

11. A backlight module, comprising:
a light emitting element array comprising a plurality of light emitting elements that emit blue light;
a quantum dot film disposed on a light-emergent side of the light emitting element array and having a middle area and an edge area, the edge area surrounding the middle area; and
a light conversion layer disposed on the light-emergent side of the light emitting element array, wherein an orthographic projection of the light conversion layer on the quantum dot film is in the edge area of the quantum dot film, a material of the light conversion layer comprises a first light conversion material configured to emit red light under excitation of light from the light emitting element and a second light conversion material configured to emit green light under excitation of light from the light emitting element,
wherein the light conversion layer comprises a plurality of light conversion units spaced apart from each other, a material of each of the plurality of light conversion units comprises the first light conversion material and the second light conversion material, and
volumes of the plurality of light conversion units are gradually increased along the direction from the center to the edge of the quantum dot film.

12. The backlight module of claim 1 , wherein the light conversion layer comprises a plurality of light conversion units spaced apart from each other, a material of each of the plurality of light conversion units comprises the first light conversion material and the second light conversion material, wherein volumes of the plurality of light conversion units are gradually increased along the direction from the center to the edge of the quantum dot film.

13. The backlight module of claim 11 , wherein a dimension of each of the plurality of light conversion units in a length direction of the quantum dot film and a dimension of the light conversion unit in a width direction of the quantum dot film are both between 5 μm and 100 μm; and a thickness of the light conversion unit is between 5 μm and 30 μm.

14. The backlight module of claim 12 , wherein a dimension of each of the plurality of light conversion units in a length direction of the quantum dot film and a dimension of the light conversion unit in a width direction of the quantum dot film are both between 5 μm and 100 μm; and a thickness of the light conversion unit is between 5 μm and 30 μm.

15. The backlight module of claim 12 , wherein both the first light conversion material and the second light conversion material are quantum dot materials; or
both the first light conversion material and the second light conversion material are phosphor materials.

16. The backlight module of claim 12 , wherein a distance between any two adjacent light emitting elements is between 1 mm and 1.5 mm, both a length and a width of each light emitting element are between 100 μm and 500 μm, a light emitting angle of each light emitting element is between 130° and 150°, a width of the edge area of the quantum dot film is between 3 mm and 5 mm, and the orthographic projection of the light conversion layer on the quantum dot film is in contact with each side edge of the middle area and in contact with each side edge of the quantum dot film.

17. The backlight module of claim 12 , wherein the quantum dot film comprises: a first barrier film layer, a second barrier film layer and a quantum dot layer between the first barrier film layer and the second barrier film layer, a

Assignees

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

Inventors

• Wang Zhiqiang
• Song Fangyu
• Ma Xin
• Wang Qiuli
• Yao Jianfeng
• Sun Chuan

Classifications

• G02F1/01791 Primary

  Quantum boxes or quantum dots · CPC title

• G02F1/133603 Primary

  with LEDs · CPC title

• G02F1/133614

  using photoluminescence, e.g. phosphors illuminated by UV or blue light · CPC title

• G02F1/133607

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