Can contactless fingerprints be compared to existing database?

The major development of fingerprint technology in the form of wet-ink fingerprinting was initiated and improved for forensic applications by Scotland Yard about 100 years ago. In recent years, new fingerprinting methods such as live scan and contactless methods were developed and continue to evolve. Now-a-days, compatibility between three fingerprinting libraries, namely wet-ink, live-scan and contactless becomes to be a critical problem. The large numbers of people travelling and crossing the borders are subjected to fingerprinting. The database of travelers is much larger than criminal one. In this environment, the need to produce speedy comparison results starts to be problematic because it is done by human operator to provide reliable judgment. From the technical standpoint, fingerprinting methods have improved rapidly to an extent where wet-ink fingerprinting has now been replaced by computer scanner generated images of finger, i.e. digital imaging, and recently developed contactless line scan. In current study, we developed certain steps which will make contactless fingerprints comparable to fingerprints in the other two libraries. The proposed steps are applicable to any contactless fingerprinting technique. The rate of success in comparing these three libraries is 82%. The somewhat low accuracy is introduced by the fact that in the contactless methods the position of the finger is free and not necessarily repeatable. To the contrary, contact based wet-ink and digital imaging do handle a finger in the same repeatable position. Therefore, improving designs of holders for examined fingers in contactless setting should improve the rate of success.