| 摘要 |
PURPOSE:To improve the S/N by providing a circuit extracting an element output of one horizontal line by n-times in the speed being n-times that of a horizontal synchronizing pulse and a circuit adding outputs of the extracting circuit by n-times in a camera using a solid-state image pickup element as an image sensor. CONSTITUTION:An electric charge of an element output of the same horizontal line generated in response to the strength of irradiated light is extracted repetitively in a period being 1/n of one horizontal time in response to the electric charge storage time of a sensor 1 in a signal processing circuit 2. The extracted signal is A/D-converted by an A/D converter 3, added by an adder circuit 4, read by taking one horizontal period as the period and D/A-converted by a D/A converter 6. The element output of the next horizontal line is extracted similarly during the D/A conversion and the output is added by S-times at an adder circuit 5. The video image added by n-times is obtained as an output of the D/A converter 6 by repeating the similar operations to decrease random noise to 1/n<1/2>. |
