Fingerprint sensor under thin face-sheet with aperture layer

• US 9,959,444 B2
• Filed: 09/01/2016
• Issued: 05/01/2018
• Est. Priority Date: 09/02/2015
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Young, Hong G., Chin, Raymond, Jones, Eric, Fong, Kelvin
• Primary Examiner(s): Edun, Muhammad N
• Application Number:
  US15/255,037
• Publication Number:
  US 20170061193A1
• Time in Patent Office: 607 Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing

Abstract

An input device for fingerprint sensing and proximity sensing includes a cover layer, where a top surface of the cover layer is configured to provide an input surface for a finger, a substrate having a cavity disposed below the cover layer, and a fingerprint sensor disposed below the cover layer and in the cavity of the substrate. A first adhesive layer is disposed between a top surface of the fingerprint sensor and a bottom surface of the cover layer in a fingerprint sensing area. A second adhesive layer is disposed between a top surface of the substrate and the bottom surface of the cover layer in a proximity sensing area.

Claims

1. An input device for fingerprint sensing and proximity sensing, the input device comprising:

a glass cover layer, wherein a top surface of the glass cover layer is configured to provide an input surface for a finger;

a printed circuit board disposed below the glass cover layer, the printed circuit board comprising a cavity;

a fingerprint sensor disposed below the glass cover layer and disposed in the cavity of the printed circuit board layer;

a first adhesive layer disposed between a top surface of the fingerprint sensor and a bottom surface of the glass cover layer, the first adhesive layer being disposed in a fingerprint sensing area that is within an area of the cavity; and

a second adhesive layer disposed between a top surface of the printed circuit board and the bottom surface of the glass cover layer, the second adhesive layer being disposed in a proximity sensing area that is outside of the area of the cavity.

2. The input device of claim 1, wherein the second adhesive layer has a Young'"'"'s modulus greater than about 250 MPa.

3. The input device of claim 2, wherein the second adhesive layer comprises an optically clear liquid epoxy adhesive having a Young'"'"'s modulus greater than 250 MPa.

4. The input device of claim 1, wherein the second adhesive layer comprises a liquid adhesive, and wherein the first adhesive layer comprises a thin film adhesive or a liquid adhesive.

5. The input device of claim 1, wherein the first adhesive layer disposed in the fingerprint sensing area is thinner than the second adhesive layer disposed in the proximity sensing area.

6. The input device of claim 1, wherein the second adhesive layer comprises an aperture in the fingerprint sensing area, wherein the first adhesive layer is disposed in the aperture of the second adhesive layer.

7. The input device of claim 1, further comprising:

an ink layer disposed between the bottom surface of the glass cover layer and the top surface of the printed circuit board.

8. The input device of claim 7, wherein the ink layer is disposed between the bottom surface of the glass cover layer and the second adhesive layer.

9. The input device of claim 7, wherein the second adhesive layer is disposed between the bottom surface of the glass cover layer and the ink layer.

10. The input device of claim 7, wherein the ink layer is disposed on the bottom surface of the glass cover layer.

11. The input device of claim 7, wherein the ink layer is disposed in the proximity sensing area and the fingerprint sensing area.

12. The input device of claim 7, wherein the ink layer is disposed in the proximity sensing area, and wherein the fingerprint sensing area is free of the ink layer.

13. The input device of claim 1, wherein the printed circuit board comprises an array of touch sensor electrodes.

14. The input device of claim 1, wherein the glass cover layer has a thickness between 0.10 millimeters and 0.30 millimeters.

15. The input device of claim 1,

wherein the second adhesive layer comprises a liquid adhesive having a Young'"'"'s modulus greater than 250 MPa;

wherein the first adhesive layer comprises a liquid adhesive;

wherein the first adhesive layer is thinner than the second adhesive layer; and

wherein the glass cover layer has a thickness between 0.10 millimeters and 0.30 millimeters.

16. The input device of claim 1,

wherein the first adhesive layer and the second adhesive layer are adhered to a bottom surface of the glass cover layer and have a Young'"'"'s modulus greater than 250 MPa;

and

wherein the first adhesive layer is thinner than the second adhesive layer.

17. An input device for fingerprint sensing and proximity sensing, the input device comprising:

a cover layer, wherein a top surface of the cover layer is configured to provide an input surface for a finger;

a substrate disposed below the cover layer, the substrate comprising a cavity;

a fingerprint sensor disposed below the cover layer and disposed in the cavity of the substrate;

a first adhesive layer disposed between a top surface of the fingerprint sensor and a bottom surface of the cover layer, the first adhesive layer being disposed in a fingerprint sensing area that is within an area of the cavity; and

a second adhesive layer disposed between a top surface of the substrate and the bottom surface of the cover layer, the second adhesive layer being disposed in a proximity sensing area that is outside of the area of the cavity.

18. The input device of claim 17, wherein the substrate comprises a PET film.

19. The input device of claim 17, further comprising:

a display device disposed below the substrate,

wherein the substrate comprises a film, wherein a first area of the film is disposed in an active area of the display device, and wherein the first area of the film is optically clear.

20. The input device of claim 19, wherein a second area of the film is disposed outside of the active area of the display device, wherein the second area of the film is opaque.

21. The input device of claim 19, wherein the fingerprint sensor is disposed outside of the active area of the display device.

22. The input device of claim 17, wherein the first adhesive layer extends across the fingerprint sensing area and the proximity sensing area, wherein the second adhesive layer extends across the proximity sensing area, and wherein the fingerprint sensing area is free of the second adhesive layer.

23. The input device of claim 17, wherein the first adhesive layer extends across the fingerprint sensing area, wherein the proximity sensing area is free of the first adhesive layer, wherein the second adhesive layer extends across the proximity sensing area, and wherein the fingerprint sensing area is free of the second adhesive layer.

24. The input device of claim 17, wherein the first adhesive layer disposed in the fingerprint sensing area is thinner than the second adhesive layer disposed in the proximity sensing area.

25. The input device of claim 17,

wherein the first adhesive layer and the second adhesive layer are adhered to a bottom surface of the cover layer and have a Young'"'"'s modulus greater than 250 MPa;

and

wherein the first adhesive layer is thinner than the second adhesive layer.