An electronic cassette that is equipped with a drive mechanism capable of accommodating a radiation detection section respectively in two casings and that is capable of changing the surface area of the radiation detection section to be externally exposed and the exposure position on the radiation detection section. Deterioration of the radiation detection section from radiation can be distributed due to control such that the same exposure position is not repeatedly employed. An electronic cassette is accordingly provided that does not suffer from uneven effects of deterioration from radiation within a single sheet radiation detection section even with repeated use.
