COMPOSITE DIFFUSER AND ULTRA-THIN DIRECT TYPE BACKLIGHT MODULE

• US 20200132890A1
• Filed: 01/19/2018
• Published: 04/30/2020
• Est. Priority Date: 12/26/2017
• Status: Active Grant

• Current Assignee: Huizhou China Star Optoelectronics Technology Co., Ltd.
• Original Assignee: Huizhou China Star Optoelectronics Technology Co., Ltd.
• Inventors: FU, Linlin, HE, Xiaoyu
• Granted Patent: US 10,775,535 B2
• Time in Patent Office: Days
• CPC Class Codes: F21S 2/005 of modular construction
• CPC Class Codes: F21V 5/00 Refractors for light sources characterised by cooling arrangements F21V29/504
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 3/0068 arranged in a single integral body or plate, e.g. laminates or hybrid structures with other optical elements G02B5/1885, G02B17/002, G02B30/27 take precedence
• CPC Class Codes: G02B 3/0087 with index gradient
• CPC Class Codes: G02B 5/02 Diffusing elements; Afocal elements
• CPC Class Codes: G02B 5/0215 the surface having a regular structure
• CPC Class Codes: G02B 6/0025 Diffusing sheet or layer; Prismatic sheet or layer
• CPC Class Codes: G02F 1/1335 Structural association of cells with optical devices, e.g. polarisers or reflectors
• CPC Class Codes: G02F 1/133603 with LEDs
• 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

This invention provides a composite diffuser plate comprising a light-emitting layer for emitting light, a middle layer for guiding light, and a light-entering layer for entering light, being sequentially stacked downwardly. At least one surface of the middle layer is provided with an array of curved protrusions. Refractive indexes of the light-emitting layer, the middle layer and the light-entering layer are gradually increased. This invention further provides an ultra-thin direct type backlight module. In the composite diffuser plate of this invention, in addition to a gradual increase in refractive indexes of the light-emitting layer, the middle layer and the light-entering layer, the middle layer is provided with a microstructure having curved protrusions, which further enhances diverging effect of emitting angle. The direct-light TV can increase a light-emitting area with a small OD value, and thus improves a LED Mura problem, realizing a slim direct-light TV and enhancing market competitiveness.

Claims

1. A composite diffuser plate comprising a light-emitting layer for emitting light, a middle layer for guiding light, and a light-entering layer for entering light, which are sequentially stacked from top to bottom, wherein at least one surface of the middle layer is provided with an array of curved protrusions, and refractive indexes of the light-emitting layer, the middle layer and the light-entering layer are gradually increased.

2. The composite diffuser plate as claimed in claim 1, wherein the light-emitting layer and the light-entering layer are fully adhered to the middle layer respectively.

3. The composite diffuser plate as claimed in claim 2, wherein both surfaces of the middle layer are provided with curved protrusions in an array respectively.

4. The composite diffuser plate as claimed in claim 3, wherein a surface of the curved protrusion is a part of a spherical surface.

5. The composite diffuser plate as claimed in claim 2, wherein a surface of the curved protrusion is a part of an ellipsoidal surface, and the curved protrusion is a spindle body.

6. The composite diffuser plate as claimed in claim 4, wherein each of the curved protrusions has a height smaller than a width thereof.

7. The composite diffuser plate as claimed in claim 6, wherein each of the curved protrusions has a width smaller than a diameter of the spherical surface of the curved protrusion.

8. The composite diffuser plate as claimed in claim 1, wherein there is a gap in every two adjacent curved protrusions.

9. The composite diffuser plate as claimed in claim 8, wherein each of the curved protrusions is same to the others, and gaps in respective two adjacent curved protrusions have a same width.

10. The composite diffuser plate as claimed in claim 7, wherein there is a gap in every two adjacent curved protrusions.

11. The composite diffuser plate as claimed in claim 10, wherein each of the curved protrusions is same to the others, and gaps in respective two adjacent curved protrusions have a same width.

12. An ultra-thin direct type backlight module comprising an LED light source and a composite diffuser plate, wherein the LED light source emits light toward the composite diffuser plate and is disposed adjacent to the composite diffuser plate with Interval, wherein the composite diffuser plate comprises a light-emitting layer for emitting light, a middle layer for guiding light, and a light-entering layer for entering light, which are sequentially stacked from top to bottom, and wherein at least one surface of the middle layer is provided with an array of curved protrusions, and refractive indexes of the light-emitting layer, the middle layer and the light-entering layer are gradually increased.

13. The composite diffuser plate as claimed in claim 12, wherein the light-emitting layer and the light-entering layer are fully adhered to the middle layer respectively.

14. The composite diffuser plate as claimed in claim 13, wherein both surfaces of the middle layer are provided with curved protrusions in an array respectively.

15. The composite diffuser plate as claimed in claim 14, wherein a surface of the curved protrusion is a part of a spherical surface.

16. The composite diffuser plate as claimed in claim 13, wherein a surface of the curved protrusion is a part of an ellipsoidal surface, and the curved protrusion is a spindle body.

17. The composite diffuser plate as claimed in claim 15, wherein each of the curved protrusions has a height smaller than a width thereof.

18. The composite diffuser plate as claimed in claim 17, wherein each of the curved protrusions has a width smaller than a diameter of the spherical surface of the curved protrusion.

19. The composite diffuser plate as claimed in claim 18, wherein there is a gap in every two adjacent curved protrusions, each of the curved protrusions is same to the others, and gaps in respective two adjacent curved protrusions have a same width.

20. An ultra-thin direct type backlight module comprising an LED light source and a composite diffuser plate, wherein the LED light source emits light toward the composite diffuser plate and is disposed adjacent to the composite diffuser plate with Interval, wherein the composite diffuser plate comprises a light-emitting layer for emitting light, a middle layer for guiding light, and a light-entering layer for entering light, which are sequentially stacked from top to bottom, and wherein at least one surface of the middle layer is provided with an array of curved protrusions, refractive indexes of the light-emitting layer, the middle layer and the light-entering layer are gradually increased, there is a gap in every two adjacent curved protrusions, each of the curved protrusions is same to the others, and gaps in respective two adjacent curved protrusions have a same width.