Method and device for recording a fingerprint, with authenticity identification

摘要

The disclosure relates to a method for recording a fingerprint, with authenticity identification, using a fingerprint recording device which is connected to a data processing instrument and has a prism body with a contact face, an illumination unit for illuminating a finger disposed on the contact face, and a first camera sensor for recording a fingerprint image.

主权项

1. A method for recording a fingerprint, with authenticity identification, comprising:
using a fingerprint recording device which is connected to a data processing instrument and has a prism body with a contact face, an illumination unit for illuminating a finger disposed on the contact face and a first camera sensor, which are configured and arranged such that the camera sensor can record a fingerprint image either according to the principle of frustrated total internal reflection (FTIR) or according to the principle of total internal reflection (TIR), wherein a spectrometer with a slit-shaped stop running along a first direction for cutting out a slit-shaped region of the light reflected by the finger disposed on the contact face, brings about spectral spread in a second direction which differs from the first direction and, with a second camera sensor, records a multiplicity of spectra corresponding to a multiplicity of successive pixels, to which spatial data is assigned along the first direction of the stop, cutting out, in the recorded fingerprint image of the first camera sensor, a region corresponding to the region defined by the stop of the spectrometer, identifying epidermal ridges and troughs situated therebetween in this region, and determining the spatial data thereof along the first direction of the stop, wherein the spatial data relating to the ridges and troughs in the fingerprint image is used to combine those spectra from the multiplicity of spectra which, according to the spatial data thereof, are situated in ridges determined in the fingerprint image so as to form a ridge spectrum and to combine the spectra from the multiplicity of spectra which, according to the spatial data thereof, are situated in the troughs so as to form a trough spectrum, the ridge spectrum and the trough spectrum are normalized to the same overall intensity and these are subtracted from one another in order to form a difference spectrum, and examining the difference spectrum for features indicating the presence of covering materials foreign to the body and rejecting the authenticity if these are present.