UART Fingerprint Reader Serial Module for Arduino Locks, Secure Your Project with Biometrics Make adding fingerprint detection and verification super simple onboard processor STM32F205, commercial fingerprinting algorithm, optical sensor Applications: Fingerprint lock/ Fingerprint safe deposit box/Access control system/Person identification/ Authority management etc Typically used in safes - there's a high powered DSP chip that does the image rendering, calculation, feature-finding and searching.