Patent ID: 7956925

Claim:
An image sensor readout method for reading out signal charges from an area sensor where a plurality of image pickup elements are arranged in matrix, the signal charges being accumulated in said plurality of image pickup elements, wherein: a first exposure time and second exposure time different in time length from each other are set, and thereafter each of said first exposure time and said second exposure time is then allocated individually to each line of said area sensor; said first exposure time and said second exposure time within one field is set based on a readout timing signal for each line generated by shifting a readout timing reference signal by a first shift register and a reset timing signal for each line generated by shifting a charge sweep-out pulse signal by a second shift register, wherein said first exposure time and said second exposure time set for each one line within one field is made different in time length depending on whether or not said reset timing signal for said each line is masked; said signal charges accumulated in said image pickup elements in said allocated first exposure time and second exposure time are read out more than once in a cycle of said readout timing reference signal per line of said area sensor in accordance with said readout timing reference signal; an OB component, which is read out along with said signal charges from an optical black pixel arranged in each line of said area sensor, is computed; and said computed result of said OB component is subtracted from said signal charges being read out or from a computed result of said signal charges, and the subtracted result is synthesized per screen of said area sensor.