CAPACITIVE FINGERPRINT SENSOR, FINGERPRINT SENSING DEVICE, AND IDENTIFICATION CONTROL METHOD FOR SAME

摘要

A capacitive fingerprint sensor, fingerprint sensing device, and identification control method for the same. The sensor comprises a substrate, a dielectric layer (2), a patterned conductor layer (4), a capacitive sensing conductor layer (6), a readout circuit (7), and a processing control unit (8). Accurate capacitance sensing in a vertical direction is achieved by means of an internal electric field channel formed by the dielectric layer (2) and having a first dielectric constant and a second dielectric constant, and an electrostatic lens constructed via the patterned conductor layer (4) according to a predetermined voltage to change a focus of an electric field. In this way, the present invention achieves accuracy of sensed capacitance by means of improving initial sensing conversion, and preventing signal aliasing caused by a source sensing parameter, thereby essentially solving the existing problems of inaccuracy of sensed capacitive information, a poor fingerprint resolution, and insufficient fingerprint information that cause poor fingerprint authentication performance.