BILL VALIDATORS (Bank note acceptors)
Contemporary bill validator is a electro mechanical device that optically scans bank note to determine authenticity and denomination. Top of the art sensors and complex recognition algorithms are used to ensure very high security. Accepted notes are routed and stacked within the removable, lockable, cassette. Whole process is controlled by embedded microcontroller that communicates with host device such as vending machine or gaming machine to facilitate purchase of goods or funds transfer.

Validator at work
Once inserted, bank note is scanned by a set of optical and magnetic sensors that analyze variuos properties such as: ink colour, paper quality and magnetic presence as well as other security features embedded in the banknote. Collected data is then compared to a database of notes preprogrammed in the memory. Once match is achieved, decision wheather to accept or rejected the note is made by a host controller.