Patent ID: 8803976

Claim:
An image pickup apparatus, comprising: an image pickup element having a plurality of pixels; and a radiation/shielding portion configured to radiate/shield an electromagnetic wave for said image pickup element in such a way that a partial pixel selective radiation state in which the electromagnetic wave is radiated to a part of said pixels in said image pickup element and the electromagnetic wave is shielded for the pixels other than the part of said pixels is obtained in a time division manner while the part of said pixels to each of which the electromagnetic wave is radiated is successively changed, wherein said radiation/shielding portion carries out the radiation/shielding of the electromagnetic wave for said image pickup element by reciprocating a shielding member having opening portions formed therein; and an image signal acquiring portion configured to acquire values of luminances obtained from the pixels each held in a radiation state of the electromagnetic wave by said radiation/shielding portion in a time division manner, and obtain a captured image signal for one frame based on the values thus acquired, wherein said plurality of pixels in said image pickup element are classified into at least two kinds of first pixels and second pixels; and said image signal acquiring portion calculates differences between peak values of luminances from said first pixels and peak values of luminances from said second pixels when each of said first pixels is set in the radiation state and each of said second pixels is set in the shielding state by said radiation/shielding portion as first difference values, calculates differences between peak values of luminances from said first pixels and peak values of luminances from said second pixels when each of said first pixels is set in the shielding state and each of said second pixels is set in the radiation state by said radiation/shielding portion as second difference values, and obtains the captured image signal for one frame based on the first difference values and the second difference values.