Introduction

Vascular Pattern Recognition, also commonly referred to as Vein Pattern Authentication, is a fairly new biometric in terms of installed systems. Using near-infrared light, reflected or transmitted images of blood vessels of a hand or finger are derived and used for personal recognition. Different vendors use different parts of the hand, palms, or fingers, but rely on a similar methodology. Researchers have determined that the vascular pattern of the human body is unique to a specific individual and does not change as people age. Claims for the technology include that it:

• Is difficult to forge — Vascular patterns are difficult to recreate because they are inside the hand and, for some approaches; blood needs to flow to register an image.
• Is contact-less — Users do not touch the sensing surface, which addresses hygiene concerns and improves user acceptance.
• Has many and varied uses — It is deployed in ATMs, hospitals, and universities in Japan. Applications include ID verification, high security physical access control, high security network data access, and POS access control.
• Is capable of 1:1 and 1: many matching — Users’ vascular patterns are matched against personalized ID cards/smart cards or against a database of many scanned vascular patterns.

APPROACH

Vascular pattern in the back of hands

Near-infrared rays generated from a bank of light emitting diodes (LEDs) penetrate the skin of the back of the hand. Due to the difference in absorbance of blood vessels and other tissues, the reflected near-infrared rays produce an image on the sensor. The image is digitized and further processed by image processing techniques producing the extracted vascular pattern. From the extracted vascular pattern, various feature data such as vessel branching points, vessel thickness, and branching angles are extracted and stored as the template.

Vascular pattern in fingers

The basic principle of this technology is shown in Figures 1 & 2. Near-infrared rays generated from a bank of LEDs penetrate the finger or hand and are absorbed by the hemoglobin in the blood. The areas in which the rays are absorbed (i.e., veins) appear as dark areas similar to a shadow in an image taken by a Charge-Coupled Device (CCD) camera. Image processing can then construct a vein pattern from the captured image. Next this pattern is digitized and compressed so that it can be registered as a template.

Conclusion

Biometrics is a powerful tool to secure our networks such as banks, offices and personal data. It provides high security and reduces the incidence of unauthorized access in sensitive areas. But as no technology is foolproof there are some loop holes in this technology which have yet to be covered.

Some people object to biometrics for cultural or religious reasons. Others imagine a world in which cameras identify and track them as they walk down the street, following their activities and buying patterns without their consent. They wonder whether companies will sell biometric data the way they sell email addresses and phone numbers. People may also wonder whether a huge database will exist somewhere that contains vital information about everyone in the world, and whether that information would be safe there.

At this point, however, biometric systems don't have the capability to store and catalog information about everyone in the world. Most store a minimal amount of information about a relatively small number of users. They don't generally store a recording or real-life representation of a person's traits -- they convert the data into a code. Most systems also work in only in the one specific place where they're located, like an office building or hospital. The information in one system isn't necessarily compatible with others, although several organizations are trying to standardize biometric data.

However above all these advantages and disadvantages this technology will be creating ripples in the field of security and privacy.