摘要 |
A device for sensing and digitizing a fingerprint from a subject finger comprising a prism, a pixilated illuminating radiation source such as a surface-emitting laser or a radiation source and a LCD affixed to the bottom surface of the prism and providing for the internal illumination, with a plurality of sub-beams, of the contact surface where the finger of the subject is pressed and the top surface of the prism, and a photoelectric sensor to detect the sub-beam radiation reflected from the fingerprint valley points. The fingerprint ridge contact points do not reflect incident sub-beam radiation. A computer can provide for sequential emission of the sub-beams so that a single cell photoelectric sensor can be used to detect the reflected sub-beams or a multiple cell photoelectric sensor can be used, with each cell corresponding to a particular sub-beam. Reflected sub-beam radiation corresponds to a fingerprint valley point. Non-reflected sub-beam radiation corresponds to a fingerprint ridge point. The fingerprint is converted to a set of binary codes that can be used for imaging or identification purposes.
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