PROBLEM TO BE SOLVED: To prevent occurrence of failure by using a buffer material attachable to and detachable from the outside of an electric cassette.SOLUTION: An electronic cassette comprises: a scintillator 41 for converting irradiated X-rays into light a TFT substrate 42 that is photoelectric conversion means for converting light emitted from the scintillator 41 into electric signals and in which a light detection surface, provided with a photo diode for performing photoelectric conversion and a TFT for performing readout, is disposed facing the scintillator 41 a housing 31 that houses the scintillator 41 and the TFT substrate 42 a carbon plate 33b that is made of a material transmitting X-rays, is disposed in an aperture provided on a surface of the housing 31 irradiated with X-rays and constitutes an interior surface of the housing 31 and a buffer material 33a that is made of a material transmitting X-rays, is provided on a front surface side of the carbon plate 33b so as to be exposed on the surface of the housing 31 and absorbs an impact applied to the carbon plate 33b.COPYRIGHT: (C)2012,JPO&INPIT【課題】電子カセッテの外部から着脱自在な緩衝材により、不具合が生じることを防止する。【解決手段】照射されたX線を光に変換するシンチレータ41と、シンチレータ41から放射された光を電気信号に変換する光電変換手段であり、光電変換を行うフォトダイオード及び読み出しを行うためのTFTが設けられた光検出面をシンチレータ41に向けて配置されるTFT基板42と、シンチレータ41及びTFT基板42を収容する筐体31と、X線を透過する材料からなり、X線が照射される筐体31の表面に設けられた開口に配置されるとともに、筐体31の内面を構成するカーボン板33bと、X線を透過する材料からなり、筐体31の表面に露呈するようにカーボン板33bの前面側に設けられ、カーボン板33bに加わる衝撃を吸収する緩衝材33aと、を備える。【選択図】図3