| 摘要 |
PROBLEM TO BE SOLVED: To improve a detecting accuracy of a surface shape recognition circuit by providing an amplifier circuit for amplifying a level of a signal by a signal generating means (detecting element) to produce an output to an output circuit. SOLUTION: The surface shape recognition sensor circuit recognizes a surface shape having a fine protrusion and recess pattern such as a person's fingerprint, an animal's muzzle pattern or the like. In a detecting element 10 in which an electric amount is changed according to a finger's contact with an object to be recognized, a finger's skin brought into contact with a passivation film 17 functions as an electrode, and an electrostatic capacity is formed between the electrode and a sensor electrode 16. This capacity alters according to the finger's protrusion and recess pattern for forming the fingerprint. After an output signal of the element 10 is level amplified by an amplifier 30, the signal is converted into a desired signal, and output from each sensing unit. The signal output from the each unit is a signal for reflecting the protrusion and recess pattern of the fingerprint. Accordingly, a fingerprint pattern can be detected based on the signals.
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