An image processing device comprising: first A/D converters that receive output signals of respective columns of a plurality of pixels arranged in a matrix form, convert the output signals into first digital signals, and output the first digital signals; a second A/D converter that receives a correction signal, converts the correction signal into a second digital signal, and outputs the second digital signal; a first correction calculation unit that produces a first correction formula; a second correction calculation unit that produces a second correction formula based on the second digital signal; a determination unit that compares a coefficient of the second correction formula and a coefficient of a second correction formula produced before the second correction formula, and determines whether or not to produce the first correction formula based on the comparison result; and a signal output unit that outputs an update signal when it is determined to produce the first correction formula.