Biometric image sensing

• US 8,866,347 B2
• Filed: 05/27/2011
• Issued: 10/21/2014
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: IDEX Biometrics ASA
• Original Assignee: Idex ASA
• Inventors: Benkley, Fred G. III
• Primary Examiner(s): Deberadinis, Robert L.
• Application Number:
  US13/118,243
• Publication Number:
  US 20120134549A1
• Time in Patent Office: 1,243 Days
• Field of Search: 307/116
• US Class Current: 307/116
• CPC Class Codes: G01N 27/04 by investigating resistance
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger

Abstract

An novel sensor is provided having a plurality of substantially parallel drive lines configured to transmit a signal into a surface of a proximally located object, and also a plurality of substantially parallel pickup lines oriented proximate the drive lines and electrically separated from the pickup lines to form intrinsic electrode pairs that are impedance sensitive at each of the drive and pickup proximal locations.

Claims

1. An impedance sensor, comprising:

a plurality of substantially parallel drive lines configured to transmit a signal to a proximally located object; and

a plurality of substantially parallel pickup lines oriented substantially perpendicular to the drive lines and separated from the pickup lines by a dielectric to form intrinsic electrode pairs that are impedance sensitive at each drive and pickup crossover location.

2. The impedance sensor according to claim 1, where the plurality of substantially parallel pickup lines have variable pitch.

3. The impedance sensor according to claim 1, where the plurality of substantially parallel pickup lines have variable line width.

4. The impedance sensor according to claim 1, where the plurality of substantially parallel pickup lines operate with a duty cycle different from fifty percent.

5. The impedance sensor according to claim 1, where the plurality of substantially parallel pickup lines operate with a duty cycle that is about fifty percent.

6. The impedance sensor according to claim 1, where the plurality of substantially parallel drive lines have variable pitch.

7. The impedance sensor according to claim 1, where the plurality of substantially parallel drive lines have variable line width.

8. The impedance sensor according to claim 1, where the plurality of substantially perpendicular drive lines operate with a duty cycle different from fifty percent.

9. The impedance sensor according to claim 1, where the plurality of substantially parallel pickup lines operate with a duty cycle of about fifty percent.

10. The impedance sensor according to claim 1, wherein the dielectric is a flexible substrate having both the drive lines located proximate one side of the dielectric and the pickup lines located proximate an opposite side of the dielectric.

11. The impedance sensor according to claim 1, wherein the dielectric is a rigid substrate having both the drive lines located proximate one side of the dielectric and the pickup lines located proximate an opposite side of the dielectric.

12. The impedance sensor according to claim 1, further comprising a first substrate having the drive lines located proximate one surface of the first substrate and a second substrate having the pickup lines located proximate one surface of the second substrate.

13. The impedance sensor according to claim 12, wherein the first and second substrates have individual electrical connections.

14. The impedance sensor according to claim 12, wherein the first and second substrates have individual electrical connections connected to separate control processors.

15. The impedance sensor according to claim 12, wherein the first and second substrates have individual electrical connections connected to a common control processor with additional electrical connections between the first and second substrates.

16. The impedance sensor according to claim 12, wherein the first and second substrates are flexible substrates with individual input and/or output connections.

17. The impedance sensor according to claim 12, wherein the first and second substrates include one flexible substrate and one rigid substrate having individual input and/or output connections.

18. The impedance sensor according to claim 1, wherein the drive and pickup lines include a substantially transparent conductor material and the dielectric is made from a substantially transparent dielectric material.

19. The impedance sensor according to claim 1, wherein the drive and pickup lines include a substantially transparent conductor material and the dielectric is made from a substantially transparent dielectric material.

20. The impedance sensor according to claim 19, wherein the drive and pickup lines have individual electrical connections.

21. A fingerprint sensing system, comprising:

a layered planar fingerprint sensor array configured to receive a static fingerprint image; and

a switch embedded within the layered fingerprint sensor array in a manner that allows a user to contact the switch simultaneously while contacting the sensor array.

22. The system according to claim 21, wherein the switch is further configured to allow a user to actuate the embedded switch simultaneously while contacting the sensor.

23. The system according to claim 21, wherein the switch is further configured to allow a user to depress a second switch simultaneously while contacting the sensor.

24. The system according to claim 21, wherein the switch and fingerprint sensor array are configured to allow a user to contact the switch to provide power to the sensor and to initiate a user validation sequence that authenticates the user fingerprint against one or more previously stored in memory before granting user access to the device.

25. The system according to claim 21, wherein the switch and fingerprint sensor array are configured to allow a user to contact the embedded switch to provide power to the sensor and to simultaneously initiate a user validation sequence that authenticates the user fingerprint against one or more previously stored in memory before granting user access to the device.

26. The system according to claim 21, wherein the layered planar fingerprint sensor includes a first layered substrate having drive lines with electrical connections layered on a second layered substrate having pickup lines and electrical connections.

27. The system according to claim 21, wherein the layered planar fingerprint sensor includes a first layered substrate having drive lines with electrical connections for connecting to a digital circuit that is layered on a second layered substrate having pickup lines and electrical connections to be connected to an analog circuit.

28. The system according to claim 21, wherein the layered planar fingerprint sensor includes a first layered substrate having drive lines with electrical connections to a multifunction host processor circuit and a second layered substrate having pickup lines and electrical connections to be connected to an analog processing circuit that sends signal back to the host processor.

29. The system according to claim 22, wherein the layered planar fingerprint sensor includes a first layered substrate having drive lines with electrical connections to a multi-function host processor circuit and a second layered substrate having pickup lines and electrical connections to be connected to an analog processing circuit that is also located inside the multifunction host processor.

30. An impedance sensor, comprising:

a first substrate having a plurality of substantially parallel drive lines configured to transmit a signal to a proximally located object; and

a second substrate substantially parallel with the first substrate and having plurality of substantially parallel pickup lines oriented substantially perpendicular to the drive lines to form an impedance sensitivity pair at each drive and pickup crossover location.

31. The system according to claim 30, wherein the drive lines have electrical connections for communicating with a digital circuit and wherein the pickup lines for communicating with electrical connections to be connected to an analog circuit.

32. The impedance sensor according to claim 30, wherein the first and second substrates have individual electrical connections connected to separate control processors.

33. The impedance sensor according to claim 30, wherein the first and second substrates are flexible substrates with individual input and/or output connections.

34. The impedance sensor according to claim 30, wherein the first and second substrates include one flexible substrate and one rigid substrate having individual input and/or output connections.

35. A sensor, comprising:

a plurality of drive lines configured to transmit a signal to a proximally located object; and

a plurality of pickup lines that cross over and are electrically separated from the drive lines to form impedance sensitive electrode pairs at each drive and pickup crossover location.

36. An impedance sensor, comprising:

a rigid substrate;

a plurality of drive lines mounted on the rigid substrate;

a flexible substrate located above the rigid substrate;

a plurality of pickup lines mounted on the flexible substrate; and

an insulating layer separating the plurality of drive lines and the plurality of pickup lines.

37. The impedance sensor of claim 36, wherein the plurality of pickup lines are mounted on a lower side of the flexible substrate.

38. The impedance sensor of claim 37, further comprising:

a drive circuit mounted on the rigid substrate and electrically connected to the plurality of drive lines, wherein the drive circuit is configured to apply a drive signal to one or more of the plurality of drive lines;

a pickup circuit mounted on the lower side of the flexible substrate and electrically connected to the plurality of pickup lines, wherein the pickup circuit is configured to process signals from the plurality of pickup lines.

39. The impedance sensor of claim 38, wherein the rigid substrate forms a cutout, and wherein the pickup circuit is partially enclosed by cutout.

40. The impedance sensor of claim 39, wherein the cutout is formed as a via that extends through the base substrate.

41. The impedance sensor of claim 38, wherein the pickup circuit comprises conductive pads on its upper surface, and wherein the conductive pads are arranged to substantially correspond with the plurality of the pickup lines.

42. An impedance sensor, comprising:

a rigid substrate;

a first flexible substrate located above the rigid substrate;

a plurality of drive lines mounted on the first flexible substrate;

a second flexible substrate located above the rigid substrate;

a plurality of pickup lines mounted on the second flexible substrate, wherein the second flexible substrate electrically insulates the plurality of drive lines from the plurality of pickup lines.

43. The impedance sensor of claim 42, further comprising:

a drive circuit mounted on the first flexible substrate and electrically connected to the plurality of drive lines, wherein the drive circuit is configured to apply a drive signal to one or more of the plurality of drive lines;

a pickup circuit mounted on the second flexible substrate and electrically connected to the plurality of pickup lines, wherein the pickup circuit is configured to process signals from the plurality of pickup lines.

44. The impedance sensor of claim 43, wherein the drive circuit is mounted on a lower side of the first flexible substrate and the pickup circuit is mounted on a lower side of the second flexible substrate.

45. The impedance sensor of claim 44,

wherein the rigid substrate forms a first cutout, and wherein the drive circuit is partially enclosed by the first cutout, and

wherein the rigid substrate forms a second cutout, and wherein the pickup circuit is partially enclosed by the second cutout.