Currency discriminator and authenticator

摘要

A method of detecting counterfeit bills includes the steps of determining the denomination of the bill being evaluated, generating data corresponding to the concentration of magnetic ink on the bill and comparing this data to the expected concentration of magnetic ink on a genuine bill of the same denomination. The bill is considered genuine if the data is within an acceptable range of the expected value. An apparatus for detecting counterfeit currency employs a microprocessor to control an optical scanning operation of the bill being evaluated and to generate image data that is compared to stored images corresponding to genuine denominations of currency. The denomination of the bill is determined by evaluating the correspondence between the image data and the stored images. The microprocessor also controls measurement of the concentration of magnetic ink on the bill and determines the genuineness of the bill by comparing the measured concentration of magnetic ink to the expected concentration for a bill of the same denomination. A signal indicative of whether the bill is genuine or counterfeit is generated by the microprocessor depending on whether the data is within a predetermined range of the expected value.