# US 11,309,293 B2 · Backlight module and manufacturing method thereof, and display device

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- Number: US 11,309,293 B2
- Document ID: US11309293B2
- Status: Granted
- Kind: B2
- Application number: 16/638,760
- Filed: 2019-11-15
- Published: 2021-03-18
- Granted: 2022-04-19
- Earliest claimed: 2019-11-15
- Assignees: Wuhan China Star Optoelectronics Technology Co., Ltd.
- Applicants: Wuhan China Star Optoelectronics Technology Co., Ltd
- Inventors: Yong Yang
- Web page: https://patentgrep.com/patent/US11309293B2

## CPC

- H10W 90/00: Package configurations
- H10H 20/853: characterised by their shape
- H10H 20/854: characterised by their material, e.g. epoxy or silicone resins
- H10H 20/855: Optical field-shaping means, e.g. lenses
- H10H 20/0362: {of encapsulations}
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
- H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS

## Abstract

The present disclosure provides a backlight module, a manufacturing method thereof, and a display device. The backlight module including a substrate, a plurality of LED chips disposed on the substrate, a plurality of encapsulation units encapsulating the LED chips in a one-to-one correspondence; each of the encapsulation units includes at least two encapsulation layers, an innermost one of the encapsulation layers completely covers the LED chip, and a refractive index of an encapsulation layer far from the LED chip is less than a refractive index of an encapsulation layer near the LED chip.

## Claims

### Claim 1

A backlight module, comprising:
a substrate;
a plurality of LED chips disposed on the substrate; and
a plurality of encapsulation units encapsulating the LED chips in a one-to-one correspondence, each of the encapsulation units comprises at least two encapsulation layers, wherein an innermost one of the encapsulation layers completely covers the LED chip, and a refractive index of the encapsulation layer far from the LED chip is less than a refractive index of the encapsulation layer near the LED chip;
wherein the encapsulation layer comprises a light-exiting surface, the light-exiting surface is a curved surface; and
in two adjacent encapsulation layers, an outer one of the two adjacent encapsulation layers covers the light-exiting surface of an inner one of the two adjacent encapsulation layers, wherein a radian of the light-exiting surface of the inner one of the encapsulation layers is greater than a radian of curvature of the light-exiting surface of the outer one of the encapsulation layers.

### Claim 2 (depends on 1)

The backlight module as claimed in claim 1, wherein a radius of curvature of the light-exiting surface of the inner one of the encapsulation layers is less than a radius of curvature of the light-exiting surface of the outer one of the encapsulation layers.

### Claim 3 (depends on 1)

The backlight module as claimed in claim 1, wherein
adjacent encapsulation units are not in contact with each other.

### Claim 4 (depends on 1)

The backlight module as claimed in claim 1, wherein
a refractive index of the innermost one of the encapsulation layers is less than or equal to 1.6.

### Claim 5 (depends on 1)

The backlight module as claimed in claim 1, wherein
a material of the encapsulation layers includes transparent silicone or epoxy resin.

### Claim 6 (depends on 1)

The backlight module as claimed in claim 1, wherein
a number of encapsulation layers of each of the encapsulation units is N, wherein N satisfies 2≤N≤5.

### Claim 7 (depends on 1)

The backlight module as claimed in claim 1, further comprising:
a diffusion layer disposed on a side of the encapsulation units away from the substrate;
a gap reserved between the diffusion layer and the encapsulation units; and
a light enhancement layer disposed on the diffusion layer.

### Claim 8 (depends on 1)

A display device, comprising the backlight module as claimed in claim 1.

### Claim 9

A method of manufacturing a backlight module, comprising:
providing a substrate;
arranging a plurality of LED chips on the substrate; and
forming encapsulation units on the LED chips by dispensing, spraying, or coating; wherein each of the encapsulation units individually encapsulates a corresponding LED chip, at least two encapsulation layers are sequentially formed on each of the LED chips from an inside to an outside, and a refractive index of the encapsulation layer far from the LED chip is less than a refractive index of the encapsulation layer near the LED chip;
wherein the encapsulation layer comprises a light-exiting surface, the light-exiting surface is a curved surface; and
in two adjacent encapsulation layers, an outer one of the two adjacent encapsulation layers covers the light-exiting surface of an inner one of the two adjacent encapsulation layers, wherein a radian of the light-exiting surface of the inner one of the encapsulation layers is greater than a radian of curvature of the light-exiting surface of the outer one of the encapsulation layers.

### Claim 10 (depends on 9)

The method of manufacturing the backlight module as claimed in claim 9, wherein
in the step of forming the encapsulation units, a material concentration of the encapsulation layer far from the LED chip is less than a material concentration of the encapsulation layer near the LED chip; and
a material viscosity of the encapsulation layer far from the LED chip is less than a material viscosity of the encapsulation layer near the LED chip.