An imaging unit causes each exposure corresponding to one frame period of respective second image signals in a first mode, and causes each exposure in divided sections of one frame period of the respective second image signals under different imaging conditions in a second mode. An image processing unit generates frames of respective first image signals based on each imaging signal read out in such a manner as to correspond to each exposure corresponding to one frame period in the first mode, and generates frames of the respective first image signals based on each imaging signal read out in such a manner as to correspond to each exposure of the divided sections in the second mode. An image output unit sequentially outputs frames of the second image signals set to a signal format common to the first mode and the second mode.