Fingerprint Authentication Using Optical Characteristics in a Finger

Fingerprint is widely used in various personal authentication applications. It is because that fingerprints can achieve the best balance among authentication performance, cost, size of device, and ease of use. However, most of current fingerprint sensors have some problems to be solved. Those are that captured fingerprint images are easily affected by the condition of the finger surface and the manner of finger pressing due to the sensing principle, and it can degrade authentication performance. To solve these problems, we have developed a new fingerprint sensor that has a novel sensing principle. This sensor forms a fingerprint image based on optical characteristics of a finger's interior by scattered transmission light. Therefore, the images so obtained are not easily affected by the condition of the finger surface such as wet, wrinkled, and so on, and enable stable authentication. In this paper, we describe the operating principle of the new fingerprint sensor using optical characteristics in a finger, and show the effectiveness of the sensor by illustrating obtained fingerprint images