| 摘要 |
PURPOSE:To refuse the collation of a fingerprint by a replica by providing a noise superposition part whose oscillation is stopped when the input by the finger of an organism is performed and oscillating when the input by the replica is performed at the electrical system of a fingerprint sensor. CONSTITUTION:The noise superposition part 13 performs oscillation with high frequency ordinarily, and it is comprised so that the oscillation of a circuit can be stopped by the dielectric constant and the equivalent electrostatic capacitance, etc., of the finger when the finger of the organism approaches. As a result, a CCD 12 outputs a fingerprint image without a noise on the finger 14. Contrary to this, when the replica 15 approaches, the noise superposition part 13 continues the oscillation. As a result, the noise is superimposed on the output of the CCD 12, and unsharp fingerprint image is outputted, and noncoincidence is always obtained as the result of pattern matching with a dictionary. Thereby, it is possible to refuse the collation of the fingerprint when the input by the replica is performed. |
