The Effect of Employing Plain and Rolled Fingerprints Together on Hit Performance

Authorized agencies routinely collect both rolled and plain fingerprints, since these two types of fingerprints complement each other. Rolled fingerprints are of larger size and contain more minutiae, while plain fingerprints are less affected by distortion and have clearer ridge structures. Searching both rolled and plain fingerprints can improve the accuracy of latent matching. It is assumed that searching in this way may increase the hit rates of AFIS (automated fingerprint identification systems), as latent matching is the most problematic part in AFIS technology. In this study, both rolled and plain fingerprints of all the ten fingers of 105 individuals - 2100 single fingerprints - were collected and recorded to AFIS. Then 7243 latents produced in AFIS known to be part of collected rolled or plain fingerprints.Produced latents from core, delta, upper, lateral (left/right) and lower parts of the original fingerprints are searched within the known tenprints database, and hit and non-hit rates of latents are found. As a result, a 1.925% increase in hit rate, on average, for a latent-tenprint database search is obtained.