Fingerprint identification structure and method and display device

Abstract

The invention provides a fingerprint identification structure, a fingerprint identification method and a display device, belongs to the technical field of fingerprint identification, and can solve the problems of the exiting fingerprint identification method of low signal-to-noise ratio of an induction signal and poor fingerprint recognition accuracy. The fingerprint identification structure disclosed by the invention comprises a light emitting unit for emitting light to a finger, a light sensing unit arranged at the positions that light reflected by the finger and emitted by the light emitting unit can be received and used for generating the induction signal according to the intensity of the received light, a modulating signal generating unit for generating a modulating signal with modulation frequency and controlling the light emitting unit by the modulating signal to flicker by the modulation frequency, and a demodulation unit which is connected with the light sensing unit and used for demodulating the induction signal.

Description

technical field [0001] The invention belongs to the technical field of fingerprint identification, and in particular relates to a fingerprint identification structure and method, and a display device. Background technique [0002] With the development of technology, many display devices such as mobile phones and tablet computers begin to have a fingerprint recognition function. An existing fingerprint identification method such as figure 1 As shown, the display panel (take the liquid crystal display panel 71 as an example, a backlight unit 72 is provided outside the light incident surface) is provided with a plurality of photosensitive units 1, when the finger is pressed on the display panel, the light emitted by the display panel can be The light is reflected back to each photosensitive unit 1, and the valley 91 and ridge 92 of the fingerprint reflect light differently, so the induction signals (such as photocurrent) generated by the photosensitive unit 1 corresponding to ...

AI Technical Summary

Problems solved by technology

[0003] However, due to the limitation of the size and performance of the photosensitive device in the photosensitive unit, the induced signal (photocurrent) generated by it is generally very small; in contrast, the noise signal generated by ambient light, leakage current, parasitic capacitance, circuit interference, etc. Stronger

Therefore, the signal-to-noise ratio of the actual sensing signal is low, and the noise signal is difficult to remove, resulting in low accuracy of fingerprint recognition.

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