Title :
A 600-dpi capacitive fingerprint sensor chip and image-synthesis technique
Author :
Lee, Jeong-Woo ; Min, Dong-Jin ; Kim, Jiyoun ; Kim, Wonchan
Author_Institution :
Integrated Syst. Lab., Seoul Nat. Univ., South Korea
fDate :
4/1/1999 12:00:00 AM
Abstract :
This paper examines the possibility of a low-cost, high-resolution fingerprint sensor chip. The test chip is composed of 64×256 sensing cells (chip size: 2.7×10.8 mm2). A new detection circuit of charge sharing is proposed, which eliminates the influences of internal parasitic capacitances. Thus, the reduced sensing-capacitor size enables a high resolution of 600 dpi, even using a conventional 0.6 μm CMOS process. The partial fingerprint images captured are synthesized into a full fingerprint image with an image-synthesis algorithm. The problems and possibilities of this image-synthesis technique are also analyzed and discussed
Keywords :
CMOS image sensors; capacitive sensors; fingerprint identification; 0.6 micron; CMOS process; capacitive fingerprint sensor chip; charge sharing; chip size; detection circuit; image-synthesis technique; internal parasitic capacitances; partial fingerprint images; resolution; Capacitance; Capacitive sensors; Capacitors; Circuit synthesis; Costs; Electrodes; Fingerprint recognition; Image matching; Image sensors; Skin;
Journal_Title :
Solid-State Circuits, IEEE Journal of
