Display device including ultrasonic fingerprint sensor

Patent metadata

Field	Value
Publication number	US-11080502-B2
Application number	US-201916563126-A
Country	US
Kind code	B2
Filing date	Sep 6, 2019
Priority date	Oct 29, 2018
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

A display device includes a flexible display panel, an ultrasonic fingerprint sensor which is disposed below a rear surface of an active area of the flexible display panel and has a first thickness and a first width, a cushion structure which is disposed below the rear surface of the flexible display panel, surrounds the periphery of the ultrasonic fingerprint sensor, and has a second thickness larger than the first thickness, and a circuit board which is electrically connected to the ultrasonic fingerprint sensor and has a second width larger than the first width.

First claim

What is claimed is:

1. A display device, comprising:
a flexible display panel including an active area for emitting light;
an ultrasonic fingerprint sensor disposed below the active area of the flexible display panel, the ultrasonic fingerprint sensor spaced apart from a rear surface of the flexible display panel in a first direction;
a cushion structure disposed below the flexible display panel, and disposed adjacent the ultrasonic fingerprint sensor in a second direction different from the first direction; and
a circuit board electrically connected to the ultrasonic fingerprint sensor, wherein the cushion structure includes a heat dissipation layer; and wherein the circuit board contacts and is electrically connected with the heat dissipation layer.

2. The display device of claim 1 ,
wherein the flexible display panel has a first thickness along the first direction and a first width along the second direction, wherein the circuit board has a second width along the second direction larger than the first width.

3. The display device of claim 1 ,
wherein an area of the circuit board is larger than an area of the ultrasonic fingerprint sensor, and wherein the circuit board is disposed below at least a part of the cushion structure.

4. The display device of claim 1 ,
wherein the ultrasonic fingerprint sensor is mounted to the circuit board such that the ultrasonic fingerprint sensor does not directly contact the flexible display panel.

5. The display device of claim 1 ,
further comprising:
an adhesive layer disposed between the ultrasonic fingerprint sensor and the flexible display panel.

6. The display device of claim 5 ,
wherein a thickness of the adhesive layer along the first direction is 3 μm or more.

7. The display device of claim 1 ,
wherein the ultrasonic fingerprint sensor is spaced apart from at least a part of the cushion structure in the second direction to provide a separation space between the ultrasonic fingerprint sensor and the part of the cushion structure.

8. The display device of claim 7 ,
wherein at least another part of the cushion structure is disposed on a top surface of the ultrasonic fingerprint sensor and covers the separation space.

9. The display device of claim 8 ,
wherein the cushion structure includes a black layer disposed between the flexible display panel and the ultrasonic fingerprint sensor, and wherein at least a part of the black layer covers the separation space.

10. The display device of claim 7 ,
wherein the circuit board is disposed below the ultrasonic fingerprint sensor, and covers the separation space from a rear surface of the ultrasonic fingerprint sensor.

11. The display device of claim 7 ,
wherein the cushion structure includes a shock absorbing layer, and wherein at least a part of the shock absorbing layer is spaced apart from the ultrasonic fingerprint sensor.

12. The display device of claim 11 ,
wherein the cushion structure further includes an adhesive layer disposed on the shock absorbing layer,
wherein the adhesive layer overlaps with the shock absorbing layer and is disposed on the ultrasonic fingerprint sensor to adhere to the ultrasonic fingerprint sensor.

13. The display device of claim 1 ,
wherein the heat dissipation layer is electrically grounded.

14. A display device, comprising:
a flexible display panel including an active area for emitting light;
an ultrasonic fingerprint sensor disposed below the active area of the flexible display panel, the ultrasonic fingerprint sensor spaced apart from a rear surface of the flexible display panel in a first direction;
a cushion structure disposed below the flexible display panel, and disposed adjacent the ultrasonic fingerprint sensor in a second direction different from the first direction;
a circuit board electrically connected to the ultrasonic fingerprint sensor; and
a shielding layer disposed between the ultrasonic fingerprint sensor and the flexible display panel, the shielding layer formed of metal and configured to block interference between a signal generated from the flexible display panel and a signal generated from the ultrasonic fingerprint sensor, wherein the cushion structure includes a heat dissipation layer; and wherein the circuit board contacts and is electrically connected with the heat dissipation layer.

15. The display device of claim 14 ,
wherein the shielding layer is electrically connected to the heat dissipation layer.

16. A display device, comprising: a flexible display panel including an active area for emitting light;
an ultrasonic fingerprint sensor disposed below the active area of the flexible display panel;
a cushion structure disposed below the flexible display panel in a first direction, and disposed adjacent the ultrasonic fingerprint sensor in a second direction different from the first direction; and
a circuit board electrically connected to the ultrasonic fingerprint sensor, wherein the cushion structure includes a heat dissipation layer; and wherein the circuit board contacts and is electrically connected with the heat dissipation layer.

17. The display device of claim 16 ,
wherein the cushion structure is formed with an opening area, and wherein the ultrasonic fingerprint sensor is disposed within the opening area of the cushion structure.

18. The display device of claim 17 ,
wherein the circuit board is disposed below the ultrasonic fingerprint sensor and configured to cover the opening area from a rear surface of the ultrasonic fingerprint sensor.

Assignees

• Lg Display Co Ltd

Inventors

• Lee Youngsoo
• Gong Namyong
• Lee Namseok
• Kim Jinyeol
• Choi Sungpil
• Min Hyunjun

Classifications

• G06V40/1306 Primary

  non-optical, e.g. ultrasonic or capacitive sensing · CPC title

• G06F1/1652

  the display being flexible, e.g. mimicking a sheet of paper, or rollable · CPC title

• H05K1/0278

  Rigid circuit boards or rigid supports of circuit boards locally made bendable, e.g. by removal or replacement of material · CPC title

• G06F1/1626 Primary

  with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs] · CPC title

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title