| 摘要 |
PURPOSE:To compensate the temperature dependency of a dark current by providing a stand-by light-shielded photodiode array for dark current detection on the opposite side to the photodiode array of a horizontal scanning circuit. CONSTITUTION:On the right-hand side of the horizontal scanning circuit 6, an additional scanning circuit 7 is porvided and on the opposite side to the photodetection part 4 of the circuit 6, a stand-by photodiode array 8 is provided. This array 8 is exactly the same as the photodiode array of a photodetection part 4 and covered with a light-shielding material. Therefore, the array 8 for detecting dark current necessary for a compensating circuit has the same temperature fluctuations that the photodetection part 4 has and also has the same characteristics and their noise, specially false signals are the same. Thus, the perfect compensation of dark current is performed. |
