Patent ID: 8169498

Claim:
An image pickup device comprising: an image sensor having a plurality of analog-to-digital converters for converting an analog signal to a digital signal through at least two separate steps; a first correction unit which has a correction factor for correcting nonlinear errors of the plurality of analog-to-digital converters so as to adapt to the analog-to-digital converters and corrects a nonlinear error of a digital signal output from respective analog-to-digital converters based on a correction factor corresponding to respective analog-to-digital converters, wherein the first correction unit corrects the nonlinear errors after converting the digital signals from the plurality of analog-to-digital converters into a serial output, and the first correction unit corrects the nonlinear errors for each column, based on a correction factor of an analog-to-digital converter in a corresponding column of correction factors of the same quantity as those of the analog-to-digital converters in each column.