Patent ID: 6885017

Claim:
An apparatus for discriminating a latent fingerprint residual from that of a biomass on an imaging surface of a fingerprint input apparatus, which acquires a fingerprint image by a backlight illuminated onto a fingerprint and reflected therefrom, the apparatus comprising: a backlight control means for controlling switching on and off of the backlight; an image acquisition means for acquiring a fingerprint image without illuminating the backlight onto the imaging surface; a fingerprint detection means for detecting an existence of a fingerprint from the image acquired by the image acquisition means; a main control unit consisted of a calculating means for calculating a value between gray levels of adjacent pixels of the acquired image and a comparing means for comparing the calculated value with a pre-set reference value; and a fingerprint discriminating for means whether the fingerprint detected by the fingerprint detection means is said latent fingerprint residual due to an external light, or discriminating the detected fingerprint to be a biomass fingerprint.