A contactless fingerprint sensor provides deformation-free, high-quality fingerprint images and offers users a cleaner and
more comfortable measurement environment. Here we propose and design an innovative prototype optical, contactless,
compact, fingerprint sensor that quickly produces high-quality, high-contrast interoperable fingerprint images. A proofof-
concept contactless, aliveness-testing (CAT) fingerprint sensor, which is connected to a PC via a firewire cable, was
constructed and is currently operating in our laboratory. The CAT sensor affords a more user-friendly interface
compared to existing contactless fingerprint sensors and also provides robust aliveness testing and spoof detection. In
this paper, we present the imaging system design concepts, finger aliveness detection techniques, and the user-friendly
interface approach. Various fingerprint matching results using the CAT sensor device are also presented and discussed.