Biometrics..


It can be defined as the technique of studying the physical characteristics of humans to establish identity.

The increased need for security, and it is also convenient to simply place finger on to a scanner instead of remembering a complex password.

The concept is simple. Pre-stored database is used to compare your finger impression with a record already in database. When a match is found, access is granted. A fingerprint is like waves with ridges and valleys, they are scanned to verify the authenticity.

An optical (CCD) scanner similar to the ones used in digital cameras is used for scanning. It is an array of light sensitive diodes .When they come in contact with light, they generate an electrical signal.An ADC system that converts electrical signal into digital. The scanner will also have a light source to illuminate the finger.

But before checking with the database, it checks for contrast, sharpness and sheer quality of the image captured. If the image quality seems correct enough, the scanner compares the captured fingerprint with those in the database to find any match.

Scanning and matching the entire finger surely consumes a lot of processing. Instead, the scanners could compare specific features of the fingerprint, called as minutiae. They are points where ridge lines end or bifurcation occurs.

A specific number of minutiae is matched for the print to be accepted. But it is being proved that it is possible to fool by using fake prints.