SOLID-STATE IMAGING DEVICE, AND FINGER PRINT COLLATING DEVICE USING IT

摘要

PROBLEM TO BE SOLVED: To provide a solid-state imaging device capable of exercising the imaging capacity more than that of a conventional device. SOLUTION: A sensor array 1 comprises photoelectric conversion cells disposed in a matrix. An X scanner and a Y scanner 3 scan each photoelectric conversion cell. A VGA 5 amplifies the output voltage of each photoelectric conversion cell. An ADC 6 converts the output of the VGA 5 into digital data. An average calculation unit 11 operates the average value of the output voltage of each photoelectric conversion cell in a predetermined range R of the sensor array 1. A divider 9 divides the reference value by the average value, and outputs the result to a multiplier 30. The multiplier 30 multiplies the output of a register 31 in which the gain control signal of a front frame is stored by the output of the divider 9, and outputs the result to the VGA 5 as the gain control signal. Since the gain of the VGA 5 is controlled by the average value of the output of the photoelectric conversion cell in the specified range, the gain can be adjusted correctly.