Palm vein authentication technology and its applications

This paper discusses the contactless palm vein authentication device that uses blood vessel patterns as a personal identifying factor. The vein information is hard to duplicate since veins are internal to the human body. The palm vein authentication technology offers a high level of accuracy, and delivers the following results: a false rejection rate (FRR) of 0.01%, and a false acceptance rate (FAR) of 0.00008% or lower, based on Fujitsu research using the data of 140,000 palms. Several banks in Japan have used the palm vein authentication technology for customer identification since July 2004. In addition, Fujitsu has integrated the technology into the access control of electronic door lock systems. Fujitsu plans to further expand applications for this technology by downsizing the sensor and improving the verification speed. 1. Palm vein authentication Palm vein authentication uses the vascular patterns of an individual’s palm as personal identification data. Compared with a finger [1] or the back of a hand, a palm has a broader and more complicated vascular pattern and thus contains a wealth of differentiating features for personal identification. The palm is an ideal part of the body for this technology; it normally does not have hair which can be an obstacle for photographing the blood vessel pattern, and it is less susceptible to a change in skin color, unlike a finger or the back of a hand. The deoxidized hemoglobin in the vein vessels absorb light having a wavelength of about 7.6 x 10 -4 mm within the near-infrared area [2]. When the infrared ray image is captured, unlike the image seen in Fig.1, only the blood vessel pattern containing the deoxidized hemoglobin is visible as a series of dark lines (Fig.2). Based on this feature, the vein authentication device translates the black lines of the infrared ray image as the blood vessel pattern of the palm (Fig. 3), and then matches it with the previously registered blood vessel pattern of the individual. 2. Implementation of contactless palm vein authentication The contactless palm vein authentication technology consists of image sensing and software technology. The palm vein sensor (Fig.4) captures an infrared ray image of the user’s palm. The lighting of the infrared ray is controlled depending on the illumination around the sensor, and the sensor is able to capture the palm image regardless of the position and movement of the palm. The software then matches the translated vein pattern with the registered pattern, while measuring the position and orientation of the palm by a pattern matching method.