LED BACKLIGHT MODULE, DISPLAY SCREEN AND DETECTION METHOD OF LED BACKLIGHT MODULE

• US 20200133069A1
• Filed: 09/30/2019
• Published: 04/30/2020
• Est. Priority Date: 10/26/2018
• Status: Active Grant

• Current Assignee: Foshan Nationstar Optoelectronics Company Limited
• Original Assignee: Foshan Nationstar Optoelectronics Company Limited
• Inventors: ZHAO, Qiang, LIU, Chuanbiao, QIN, Kuai, GUO, Heng, WANG, Changqi, XIE, Zongxian, FAN, Kailiang, JIANG, Chungan
• Granted Patent: US 11,314,125 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133612 Electrical details
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 2201/36 Airflow channels, e.g. constructional arrangements facilitating the flow of air
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light

Abstract

Provided is a LED backlight module, display screen and detection method of a LED backlight module. The LED backlight module includes a substrate and multiple LED chips arranged on the substrate, one first detection group is arranged on the substrate for each LED chip of more than one LED chip arranged at an interval of N LED chips connected in series, where N is greater than or equal to 0, the first detection group includes a first positive electrode detection point and a first negative electrode detection point, the first positive electrode detection point and the first negative electrode detection point of the first detection group are respectively connected to a positive electrode and a negative electrode of the each LED chip.

Claims

1. A LED backlight module, comprising a substrate and a plurality of LED chips arranged on the substrate, wherein one first detection group is arranged on the substrate for each LED chip of more than one LED chip arranged at an interval of N LED chips connected in series, N is greater than or equal to 0, wherein the first detection group comprises a first positive electrode detection point and a first negative electrode detection point, the first positive electrode detection point and the first negative electrode detection point of the first detection group are respectively connected to a positive electrode and a negative electrode of the each LED chip.

2. The LED backlight module according to claim 1, wherein a plurality of partitions are arranged on the substrate, and each partition of the plurality of partitions is provided with at least two LED chips connected in series or parallel, wherein the LED backlight module further comprises a second detection group capable of independently detecting the each partition, wherein the second detection group comprises a second positive electrode detection point and a second negative electrode detection point, the second positive electrode detection point and the second negative electrode detection point of the second detection group are respectively connected to a positive electrode and a negative electrode of the each partition.

3. The LED backlight module according to claim 2, wherein a number of the plurality of partitions is M, and a sum of a number of second positive electrode detection points and a number of second negative electrode detection points is at least M+1.

4. The LED backlight module according to claim 1, wherein the substrate has a first surface, the plurality of LED chips and the first detection group are arranged on the first surface.

5. The LED backlight module according to claim 1, wherein the substrate has a first surface and a second surface opposite to the first surface, wherein the plurality of LED chips is arranged on the first surface, the first detection group is arranged on the second surface, a through via is formed through the substrate, a conductive element is disposed in the through via, each conductive element is separately connected to one of the first detection group or the each LED chip.

6. The LED backlight module according to claim 1, wherein a positive electrode bonding pad, a negative electrode bonding pad, a conductive wire for connecting the positive electrode bonding pad to another negative electrode bonding pad adjacent to the positive electrode bonding pad and a conductive wire for connecting the negative electrode bonding pad to another positive electrode bonding pad adjacent to the negative electrode bonding pad are arranged on the substrate corresponding to the each LED chip, wherein the first positive electrode detection point is arranged on a conductive wire connected to the positive electrode bonding pad of the each LED chip, and the first negative electrode detection point is connected to a conductive wire connected to the negative electrode bonding pad of the each LED chip.

7. The LED backlight module according to claim 1, wherein the substrate has a first surface, the plurality of LED chips is arranged on the first surface, wherein the first surface is coated with an insulating reflective layer, and the reflective layer is provided with a hollowed-out partition for exposing the first positive electrode detection point, the first negative electrode detection point and a plurality of bonding pads of the plurality of LED chips.

8. The LED backlight module according to claim 7, wherein the reflective layer is a white ink layer with high temperature resistance, wherein the white ink layer has light reflectance greater than 80%.

9. The LED backlight module according to claim 7, wherein a first protective layer is disposed on the first positive detection point and the first negative detection point;

and/or,

a second protective layer is disposed on the plurality of bonding pads.

10. The LED backlight module according to claim 9, wherein the first protective layer and the second protective layer are made of a same material.

11. The LED backlight module according to claim 9, wherein each of the first protective layer and the second protective layer is an OSP film or a metal plating layer.

12. The LED backlight module according to claim 1, wherein each of the plurality of LED chips has a beam angle greater than 120°

.

13. The LED backlight module according to claim 1, wherein the plurality of LED chips has a wavelength span equal to or less than 2.5 nm;

and/or

the plurality of LED chips has a voltage drop span equal to or less than 0.1 V; and

/or

the plurality of LED chips has an optical power span equal to or less than 0.2 mW.

14. The LED backlight module according to claim 1, wherein the plurality of LED chips is packaged on the substrate by a packaging colloid.

15. The LED backlight module according to claim 14, wherein a groove is formed on a surface of the packaging colloid, wherein the groove is unconnected to a cavity of the packaging colloid for packaging the plurality of LED chips.

16. The LED backlight module according to claim 14, wherein the packaging colloid is one of a transparent packaging colloid, a YAG fluorescent powder colloid, KSF fluoride fluorescent powder or a quantum dot protective film.

17. The LED backlight module according to claim 1, wherein the substrate has a first surface and a second surface opposite to the first surface, the plurality of LED chips is arranged on the first surface, a heat dissipation layer is disposed on the second surface.

18. The LED backlight module according to claim 17, wherein the heat dissipation layer is a heat dissipation copper layer in a form of mesh spots.

19. A display screen, comprising a LED backlight module,

wherein the LED backlight module comprises a substrate and a plurality of LED chips arranged on the substrate, wherein one first detection group is arranged on the substrate for each LED chip of more than one LED chip arranged at an interval of N LED chips connected in series, N is greater than or equal to 0, wherein the first detection group comprises a first positive electrode detection point and a first negative electrode detection point, the first positive electrode detection point and the first negative electrode detection point of the first detection group are respectively connected to a positive electrode and a negative electrode of the each LED chip.

20. A detection method of a LED backlight module, comprising:

connecting, by a detection tool, to at least one second detection group on the LED backlight module to light up all LED chips in a designated partition of the LED backlight module, determining a brightness value of the designated partition with all LED chips light up, comparing the brightness value of the designated partition with a preset brightness value, and determining all LED chips in the designated partition to be qualified in response to determining that the brightness value is greater than the preset brightness value, or determining existence of an unqualified LED chip in the designated partition in response to determining that the brightness value is less than or equal to the preset brightness value; and

in response to determining that the existence of the unqualified LED chip in the designated partition, connecting, by the detection tool, to a first detection group in the partition to light up all LED chips in the designated partition one by one, and determining a position of the unqualified LED chip.