Biological backgroundFinger image recognition is perhaps the biometric feature, which is most likely associated with biometrics. The fine afford or relief on the finger berries (also called Tastballen, Latin torulus tactilis; than finger Berry called the fat pads and particularly numerous Meissner Tastk�¶rperchen-equipped, kapillarenreiche beugeseitige Vorw�¶lbung of Fingerendglieds) spreading lines or papillae (also Papillarlinien) , also at the appropriate places in the toes appear, are increases on the skin surface. These increases are determined by the intermediate grooves or depressions furchenartigen deferred. The Papillarlinien have a width of between 100 m and 300 �¼m and exhibit a nearly constant line density of approximately 500 �¼ m on the entire fingerprint. The elevation distance between a groove and a valley is between one and 20 microns. Points where these lines en verzweig or end, Minuzien called, the type and distribution of pores in addition to detection purposes. Besides the Papillarlinien are on a fingerprint about 6 pore / mm �². The smallest pores have a surface area of 60 �¼ m on, it would require a resolution of about 800 DPI for a presuppose recognition. The average wavelength is 9 pixels at a resolution of 500 DPI between two valleys or two mountains. The grooves are generally 450 �¼ m wide. The pores are about 40 �¼ m wide, which is why a sensor resolution of approximately 1,000 dpi would be required. The Papillarlinienmuster history and the people are at any time and from the ground and from various irregularities caused by the growth processes of embryonic finger skin. Several fingers have different fingerprints - even in monozygotic twins. The route, is similar to the stripes on the skin of a zebra.
(Quelle: v.Graevenitz (2006): Erfolgskritieren und Absatzchancen biometrischer Identifikationsverfahren, Lit Verlag, S. 58-62) |