Biometric modality: Vascular – what is it?
Vascular recognition is a comparatively recent biometric technology. The arrangement of veins in fingers and hands form a unique pattern that can be used to identify an individual. This pattern of veins is captured by shining a near-infrared (IR) light source through the finger/hand or reflecting it off the surface of the skin and recording the image on a charged couple device (CCD) camera. The blood in the veins and capillaries absorbs the IR light differently to the surrounding muscle tissue and transmits a clear outline of the structures back to the camera. This scanning process is typically fast (reportedly just seconds in some applications). The features are extracted from the image and stored as a digital template. The process for enrolment and verification is the same and requires the cooperation of the individual although no contact is necessary with the IR scanner or CCD camera. Vascular biometrics are used predominantly in one-to-one (1:1) verification applications. See also Eyes: Retina and Eyes: Scleral vein.