An Introduction to Biometrics - Hand Geometry Recognition

What is hand recognition?
The geometric features of the hand such as the lengths of fingers and the width of the hand are measured to identify an individual.

How does it work?
The hand geometry scanner looks for unique features in the structure of the hand. These unique features include the finger thickness, length, and width, the distances between finger joints, the hand’s overall bone structure, etc.

The user first places his or her hand onto a platen. This platen consists of 5 pegs which help the user position their fingers properly in order to insure quality enrolment and verification templates. The hand geometry scanner consists of a charged couple device camera (CCD), as well as various reflectors and mirrors in order to capture various black and white pictures of the hand. Two basic types of pictures of the hand are captured: (1) An image of the top of the hand; and (2) An image of the side of the hand.

In the enrolment phase, the user is prompted by the hand geometry scanner to place their hand on the platen three different times, so that three images can be captured and then averaged. The resulting image forms the basis for the enrolment template, which is then stored in the database of the hand geometry scanner. The enrolment phase can be accomplished in just five seconds.

In the verification phase, the user is prompted to place their hand only once on the platen. An image is captured, and forms the basis for the verification template. The verification template is compared against the enrolment template, in the same fashion as fingerprint recognition. The verification phase can be accomplished in just under one second.

In the enrolment and verification phases, the hand geometry scanner takes 96 measurements of the hand. The enrolment and verification templates are only 9 bytes.

Applications
There are numerous types of applications for which hand geometry recognition is utilized. The most recognized use for this technology is in physical access entry applications, because the system is user friendly to configure. In fact, this was the first application that this technology was used for when it first came onto the market. Another application gaining popularity for hand geometry recognition is time and attendance. Hand geometry recognition is also used for point of sale applications. Examples of this include subsidized school lunch programs and luxury hotels. All of these involve the use of the hand geometry scanner to deduct or debit money from a user’s fund account when a purchase is made. Hand geometry recognition is also utilized in the Immigration and Naturalization Service Passenger Accelerated Service System (INSPASS). With this system, frequent international business travelers can simply use their hand geometry to enter the United States, rather than waiting in immigration lines at the airport. Finally, hand geometry recognition is making a presence in the financial sector; a number of banks (in particular the Bank of America and the Nevada State Bank) are planning to adopt this technology to give customers easier and timely access to their safe deposit vaults.

Standards

Standards under development:

INCITS PN-1643-D: Information Technology-Hand Geometry Format for Data Interchange
ISO/IEC NP 19794-10: Information Technology-Biometric Data Interchange Formats-Part 10: Hand Geometry Silhouette Data

Further information

Das, R, HTG Advance Systems, An Application of Biometric Technology: Hand Geometry Recognition

Manufacturers/suppliers of hand recognition technologies:

Human Recognition Systems
IR Security & Safety
NEC
Recognition Systems

Acknowledgement

The information contained in this section was collected from the following source:

Ravi Das, HTG Advance Systems, An Application of Biometric Technology: Hand Geometry Recognition