Biometric image sensing
A 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 drive lines to form intrinsic electrode pairs that are impedance sensitive at each of the drive and pickup proximal locations. A switch is integrated with the sensor.
1. An assembly combining a fingerprint sensor with a switch, the assembly comprising:
a flexible fingerprint sensor comprising:
a flexible dielectric substrate,
a plurality of drive lines configured to transmit a signal, and
a plurality of pickup lines configured to receive at least a portion of the signal transmitted by the drive lines, wherein the pickup lines are oriented transversely to the drive lines and are physically separated from the drive lines by the flexible dielectric substrate to form a sensing area having a two dimensional array of electrode pairs that are impedance sensitive to detect ridge and valley features of a finger proximally located with respect to at least a portion of the sensing area; and
a sensor switch assembly comprising:
a base having a top surface, wherein the sensing area of the flexible fingerprint sensor is disposed over the top surface of the base, and
a switch below the sensing area,
wherein the flexible fingerprint sensor and the sensor switch assembly are constructed and arranged to allow a user to contact the switch by placing a finger on the sensing area over the switch.
2. The assembly of claim 1 , wherein the base includes an opening formed therein and the switch is disposed within the opening of the base.
3. The assembly of claim 2 , wherein a top surface of the switch is flush with the top surface of the base.
4. The assembly of claim 2 , wherein a top surface of the switch is recessed with respect to the base in the opening formed in the base.
5. The assembly of claim 1 , wherein the flexible fingerprint sensor further comprises a processor attached to the flexible dielectric substrate and connected to the drive lines and to the pickup lines.
6. The assembly of claim 1 , wherein the flexible fingerprint sensor is at least partially folded about the base.
7. The assembly of claim 6 , wherein the drive lines and the pickup lines are disposed on different portions of a first side of the flexible dielectric substrate, and wherein the flexible fingerprint sensor is folded over the base so that the portions of the flexible dielectric substrate on which the drive lines and pickup lines are disposed overlap each other on the top side of the base.
8. The assembly of claim 1 , wherein the switch comprises a switch base and a plunger.
9. The assembly of claim 1 , wherein the switch is a dome switch.
10. The assembly of claim 1 , wherein the switch comprises a plunger and wherein the flexible fingerprint sensor and the sensor switch assembly are constructed and arranged so that a finger placed on the sensing area will simultaneously depress the plunger.
11. The assembly of claim 1 , wherein the drive lines are parallel to one another and the pickup lines are parallel to one another.
12. The assembly of claim 1 , wherein the switch is a mechanical switch, and the sensor switch assembly is constructed and arranged to allow the user to actuate the switch by placing a finger on the sensing area over the switch.
13. The assembly of claim 1 , further comprising a host device, wherein the flexible fingerprint sensor and the sensor switch assembly are integrated into the host device and the switch is operatively connected to the host device to enable the switch to control an operation of the host device.
14. The assembly of claim 13 , wherein the host device is a mobile telephone or a smart phone.
15. The assembly of claim 13 , wherein the switch is configured to function as one or more of a power switch, a selector switch, or a navigation switch of the host device.
16. The assembly of claim 13 , wherein the flexible fingerprint sensor is configured to authenticate a user to enable the switch to control an operation of the host device.
17. The assembly of claim 13 , wherein the host device comprises a case, a portion of which is disposed over the top surface of the base.
18. The assembly of claim 17 , wherein an opening is formed in the case and is positioned over the sensing area of the flexible fingerprint sensor, and the opening is surrounded by a bezel.
19. A sensing module, comprising:
a fingerprint sensor assembly, comprising:
a rigid base having a top surface; and
a folded flexible sensor covering the top surface of the rigid base and at least partially wrapped around the rigid base to form a sensing surface, and
a switch disposed beneath the sensing surface, wherein the fingerprint sensor assembly and the switch are constructed and arranged to enable a finger placed on the sensing surface to activate the switch.
20. The sensing module of claim 19 , wherein a cutout is formed in the rigid base, and the switch is disposed within the cutout formed in the rigid base.