Patent ID: 8885895

Claim:
A fingerprint authentication device comprising: a fingerprint sensor that scans or images a fingerprint and acquires fingerprint image data; a processor comprising a fingerprint image correction section that generates a histogram of pixel values on the basis of the fingerprint image data acquired by the fingerprint sensor, and corrects a pixel value of each pixel by using a correction coefficient for making a first pixel value, that relates to the brightest pixel in a group of pixels at which an integrated value of a number of pixels at a dark portion side in the histogram becomes a predetermined proportion with respect to an integrated value of a number of all pixels, be a second pixel value that is brighter than the first pixel value, and a spectral data generation section that, from fingerprint image data corrected by the fingerprint image correction section, generates a spectral data matrix of which components are directions of ridges of the fingerprint and a frequency of the fingerprint; a memory that archives a registered spectral data matrix that is referred to at a time of fingerprint authentication, the processor further comprising a fingerprint verification section that verifies the spectral data matrix that has been generated at the spectral data generation section, and the registered spectral data matrix that is archived in the memory; and an output device that outputs results of authentication by the fingerprint verification section, wherein the fingerprint image correction section carries out image correction on a region of the imaged fingerprint in which a thickness of a portion corresponding to a ridge of the fingerprint is greater than a predetermined threshold value, the portion corresponding to the ridge of the fingerprint is calculated from coordinates of a pixel at which a computed edge intensity is a minimum and coordinates of a pixel at which the computed edge intensity is a maximum.