Electric field fingerprint recognition device, state control method thereof and prosthesis identification method

Abstract

The invention provides an electric field fingerprint recognition device, a state control method thereof and a prosthesis identification method. The electric field fingerprint recognition device comprises a signal acquisition module and a signal processing module. When a measurement state signal processing unit is electrically connected with a signal acquisition unit, a to-be-measured state signal processing unit is at least electrically connected with at least one signal collection unit at the periphery of the measurement state signal processing unit. The charging and discharging processes of a sensing capacitor which is electrically connected to the measurement state signal processing unit and the to-be-measured state signal processing unit, and the charging and discharging quantity of electricity of a parasitic capacitor between the measurement state signal processing unit and the to-be-measured state signal processing unit is inhibited. The device and the methods have the advantages of simple structure and saving of device cost, a problem of mutual interference between signal collection units is avoided, the fingerprint recognition device can be suitable for various application requirements, a prosthesis finger fingerprint can be judged, and the safety and the reliability of the fingerprint identification device are improved.

Description

technical field [0001] The invention relates to a fingerprint identification device and a data processing method thereof, in particular to an electric field type fingerprint identification device and a data processing method thereof. Background technique [0002] Prior art electric field type fingerprint recognition device, such as Figure 13 As shown, at least one fingerprint identification basic unit is included. The fingerprint identification basic unit includes an electrode plate 71 , a first transistor 72 as a controlled switching device, a second transistor 73 as another controlled switching device, and a charge amplifier 74 . In the process of fingerprint identification, at first turn on the first transistor 72, charge the electrode plate 71, and complete the reset of the charge amplifier 74; then turn off the first transistor 72, turn on the second transistor 73, and transfer the charge on the electrode plate 71 The output terminal of the charge amplifier 74 determi...

AI Technical Summary

Problems solved by technology

[0003] 1. Two transistors as controlled switching devices are used to realize the basic fingerprint recognition function. The structure of the basic unit of fingerprint recognition is relatively complicated, and the cost of the device is relatively high;

[0004] 2. The circuit structure is single, and it cannot form a variety of design schemes according to application requirements;

[0005] 3. There is a problem of electric field mutual interference between the fingerprint recognition basic units; there is a parasitic capacitance between the fingerprint recognition basic units, and the parasitic capacitance also participates in the charge change process during the charging and discharging process of the electrode plate, and because of The amount of charge change caused by parasitic capacitance is unpredictable, which causes the mutual interference of electric fields between the basic units of fingerprint identification and affects the accurate measurement of charge change, which in turn affects the results and accuracy of fingerprint identification;

[0006] 4. The prior art fingerprint identification device cannot judge and distinguish the fingerprints of prosthetic fingers

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