To reduce moire and false color even in both photographic modes for still image and moving image, and to achieve higher accuracy and further reduction in size.

In the optical low pass filter, a first separation element and a second separation element are arranged in order in the traveling direction of light, and a rotation drive section for rotating the optical axis of the light 180° around the center is provided. The first separation element separates incident light into the light of a first polarization component and the light of a second polarization component, orthogonal to the light of the first polarization component such that they are apart from each other by a separation distance L1(>0). The second separation element separates incident light into the light of a first polarization component and the light of a second polarization component such that they are apart from each other by a separation distance L2(>0). By rotating the second separation element with respect to the first separation element by use of the rotation drive section, the separation distance between the light of the first polarization component and the light of the second polarization component, emitted from the second separation element, is switched between LM and LS.