To detect accelerated phosphorescence emission light according to the radiation energy in a wide dynamic range, to obtain a reproduction image having high sharpness, and at the same time to nearly completely erase radiation energy that remains at a phosphor sheet by an appropriate quantity of irradiation light of erasure light, in a method and an apparatus using a line sensor for reading radiation images.

While the move in a Y direction is made by the distance of one pixel by a scanning belt, a line sensor 17 accumulates charge in a plurality of different accumulation time, and the output of the line sensor 17 is read for each accumulation time. Additionally, erasure light is applied to the phosphor sheet 1 for erasing an image that remains on the phosphor sheet 1 by the quantity of irradiation light that is controlled based on the output of the line sensor 17 that is read in accumulation time, where the accumulation is not saturated after applying excitation light to the phosphor sheet 1.