An object of the present invention is to provide a technique for detecting a radiation amount incident on a radiation imaging apparatus with higher accuracy. A plurality of first pixels arranged in an imaging area for acquiring a radiation image, a second pixel for acquiring an incident radiation dose during irradiation of radiation, and a plurality of first pixels are provided. A control unit that controls the pixel and the second pixel, the control unit accumulating charges corresponding to the radiation dose in the plurality of first pixels, and based on radiation irradiation information before radiation irradiation. While operating the second pixel at the determined radiation detection cycle, the incident radiation dose is acquired for each detection cycle, and the acquired radiation dose is obtained according to the noise amount of the noise output by the second pixel operating at the detection cycle. Is corrected, the irradiation of the radiation is stopped based on the total value of the corrected radiation dose, and the charges accumulated in the plurality of first pixels are read out after the irradiation of the radiation. [Selection diagram] Fig. 1【課題】放射線撮像装置に入射する放射線量を、より高い精度で検出する技術を提供する。【解決手段】放射線画像を取得するために撮像領域に配された複数の第１の画素と、入射する放射線量を放射線の照射中に取得するための第２の画素と、複数の第１の画素及び第２の画素を制御する制御部と、を含み、制御部は、複数の第１の画素に放射線量に応じた電荷を蓄積させるとともに、放射線の照射前に放射線の照射情報に基づいて決定した放射線の検出周期で第２の画素を動作させながら、入射した放射線量を検出周期ごとに取得し、検出周期で動作する第２の画素が出力するノイズのノイズ量に従って、取得した放射線量を補正し、補正後の放射線量の累計値に基づいて放射線の照射を停止させ、放射線の照射後に、複数の第１の画素に蓄積された電荷を読み出す。【選択図】図１
