| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a solid state image pickup device capable of correcting noise in lateral streak shape without enlarging the circuit scale and deteriorating the dynamic range. <P>SOLUTION: A solid state image pickup device includes: a clamp calculation circuit 190 for calculating a clamp value that indicates an optical black level from a digital signal in a unit pixel converted from a plurality of AD conversion parts in a prescribed time interval; a control unit for converting a digital signal in a pixel unit of a column corresponding to a column AD conversion unit 120, into a digital signal excluding an offset signal component based on the clamp value. When the difference between the clamp value and a past clamp value calculated immediately before is equal to or less than a prescribed lower limit value, the clamp calculation circuit 190 calculates a next clamp value of the clamp value by extending the prescribed time interval, and when the difference between the clamp value and the past clamp value is equal to or more than a prescribed upper limit value, the clamp calculation circuit 190 calculates the next clamp value of the clamp value by shortening the prescribed time interval. <P>COPYRIGHT: (C)2012,JPO&INPIT |
