Hand geometry

Hand geometry is a biometric that identifies users from the shape of their hands. Hand geometry readers measure a user's hand along many dimensions and compare those measurements to measurements stored in a file.

Geometry of a hand and some examples of measurements that can be taken by hand geometry reading devices.[1]

A hand geometry reading device with pegs to control the placement of the hand. Angled mirror on the left reflects the side view image of the hand to the camera. A CCD camera is beneath the keypad to take the top view image of the hand and the mirror image.[2]

Viable hand geometry devices have been manufactured since the early 1980s, making hand geometry the first biometric to find widespread computerized use.[3] It remains popular; common applications include access control and time-and-attendance operations.

Since hand geometry is not thought to be as unique as fingerprints, palm veins or irises, fingerprinting, and iris recognition remain the preferred technology for high-security applications. Hand geometry is very reliable when combined with other forms of identification, such as identification cards or personal identification numbers. In large populations, hand geometry is not suitable for so-called one-to-many applications, in which a user is identified from his biometric without any other identification.