It is important to point out that file stored in the chip card is NOT a picture of your fingerprint, it can NOT be extracted back from the card and can NOT be reverse engineered to create a fingerprint image. It is actually a special mathematical algorithm produced by fingerprint image and software in the fingerprint reader. During process of validation that algorithm is compared with actual finger presented on the reader and it takes all but under one second to prove a positive or negative match.
This biometric feature is used for many years all over the world, it is not intrusive and is widely accepted concept that every person has different fingerprint. It can't be copied or faked unlike PIN or similar type of validation.