Hand Geometry
Introduction
Hand geometry is a field of biometrics that involves the measurement and statistical analysis of the physical characteristics of an individual's hand. These characteristics include the width of the hand, the length and width of the fingers, and the angle between the fingers. Hand geometry is used in a variety of applications, including access control, time and attendance tracking, and identity verification.
History
The use of hand geometry for identification purposes dates back to the 19th century. However, the first commercial hand geometry system was not developed until the 1970s. This system, known as the Identimat, was used by the New York Police Department for access control. Since then, hand geometry has been used in a variety of applications, from airport security to employee time and attendance tracking.
Principles of Hand Geometry
Hand geometry involves the measurement of various physical characteristics of the hand. These measurements are then used to create a unique biometric template for each individual. The most commonly measured characteristics include the length and width of the fingers, the width of the hand, and the angle between the fingers. Other characteristics, such as the curvature of the fingers, can also be measured.
Measurement Techniques
There are several techniques for measuring hand geometry. The most common technique involves the use of a hand geometry reader. This device uses a light source and a camera to capture an image of the hand. The image is then processed to extract the relevant measurements. Other techniques involve the use of touch-sensitive plates or pressure sensors.
Applications
Hand geometry is used in a variety of applications. One of the most common applications is access control. In this context, hand geometry is used to verify the identity of an individual before granting them access to a secure area. Other applications include time and attendance tracking, where hand geometry is used to verify the identity of an employee when they clock in or out, and identity verification, where hand geometry is used to verify the identity of an individual for purposes such as voting or obtaining a driver's license.
Advantages and Disadvantages
Hand geometry has several advantages over other forms of biometrics. One of the main advantages is that it is non-intrusive. Unlike other forms of biometrics, such as fingerprint or iris recognition, hand geometry does not require physical contact with the individual. This makes it more acceptable to many people. Another advantage is that hand geometry is relatively easy to measure. Unlike other forms of biometrics, such as facial recognition, hand geometry does not require complex image processing techniques.
However, hand geometry also has several disadvantages. One of the main disadvantages is that it is not as accurate as other forms of biometrics. This is because the physical characteristics of the hand can change over time due to factors such as aging or injury. Another disadvantage is that hand geometry requires a relatively large sensor, which can make it impractical for use in some applications.
Future Developments
The field of hand geometry is constantly evolving, with new measurement techniques and applications being developed all the time. One of the most promising areas of research involves the use of 3D imaging techniques to capture more detailed measurements of the hand. This could potentially improve the accuracy of hand geometry and open up new applications.
