Fingerprint reading device and control module of same

Abstract

The application discloses a fingerprint reading device and a control module of the same, wherein the fingerprint reading device comprises a packaging device and a fingerprint sensor, and the control module comprises a baseplate, an optical signal sending unit, an optical signal receiving unit and a processing chip; when an infrared light signal sent by the optical signal sending unit is reflected by a finger, the infrared light signal received by the optical signal receiving unit will be strengthened, and an electric signal amplitude converted by the optical signal receiving unit will exist a preset amplitude value; and when the amplitude value of the electric signal detected by the processing chip exceeds the preset amplitude value, sending frequency of the infrared light signal of the optical signal sending unit will be increased and the fingerprint sensor will be started. Electromagnetic field interference existing in the environment will not make the amplitude value of the electric signal exceed the preset amplitude value, so that the problem about wrong starting of the fingerprint reading device caused by the electromagnetic field interference can be avoided, and working stability of the fingerprint reading device is enhanced.

Description

technical field [0001] The invention belongs to the field of automatic control, and more specifically relates to a fingerprint reading device and a control module thereof. Background technique [0002] As a biological characteristic of human beings, fingerprints are irreplaceable, non-replicable and unique. Therefore, using fingerprint as a person's identification feature has a wide application prospect. [0003] The fingerprint reading device that carries out fingerprint reading in the prior art is as figure 1 As shown, it includes: packaging device 100, copper foil 200, backlight device 300, fingerprint sensor 400, optical prism 500 and first processing chip 600; wherein, the fingerprint sensor 400 includes optical lens 401, sensor chip 402 and second Process the chip 403; the packaging device 100 has a through hole; the optical prism 500 is embedded in the through hole of the packaging device 100; the copper foil 200 is attached to the side of the optical prism 500; the...

AI Technical Summary

Problems solved by technology

For the consideration of anti-riot performance, the thickness of the optical prism 500 is relatively large. When the finger touches the optical prism 500, the change of the surface charge of the copper foil 200 is very small, so the processing chip 300 detects the A small change in the surface charge of the copper foil 200 will turn on the backlight device 300 for illumination; however, when there is electromagnetic field interference in the use environment on the surface of the fingerprint reading device, it is easy to cause a small change in the surface charge of the copper foil 200, As a result, the first processing chip 600 falsely activates the backlight device 300, reducing the working stability of the fingerprint reading device.

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