Patent ID: 9747489
Date: 2017-08-29
CPC Classifications: G06K

Claim:
1. An electric field type fingerprint identification apparatus comprising a signal acquisition module and a signal processing module; wherein, the signal acquisition module comprises at least two signal acquisition units, all of the signal acquisition units fill up an entire finger touch region and form a signal acquisition unit array, and each of the signal acquisition units comprises a sensing capacitor; the signal processing module comprises a measuring state signal processing unit and a to-be-measured state signal processing unit, the measuring state signal processing unit is configured to acquire capacitance change quantities respectively caused by convex and concave textures of fingerprints from the signal acquisition unit by charging and discharging the sensing capacitor, the to-be-measured state signal processing unit is configured to only charge and discharge the sensing capacitor of the signal acquisition unit, and the measuring state signal processing unit and the to-be measured state signal processing unit are electrically connected to the signal acquisition units controlledly; and in a case that the measuring state signal processing unit is electrically connected to at least one of the signal acquisition units and makes the at least one of the signal acquisition units be in a measuring state, the to-be-measured state signal processing unit is at least electrically connected to at least one of the signal acquisition units at the periphery of the signal acquisition unit in the measuring state and makes the at least one of the signal acquisition units be in a to-be-measured state, and charging and discharging quantities of a parasitic capacitor between the signal acquisition unit in the measuring state and the signal acquisition unit in the to-be-measured state are restrained by controlling the measuring state signal processing unit and the to-be-measured state signal processing unit to coordinate charging and discharging processes of the sensing capacitors electrically connected to the measuring state signal processing unit and the to-be-measured state signal processing unit.