Patent ID: 7541591

Claim:
A radiation imaging apparatus comprising: a conversion unit wherein a plurality of conversion elements for converting radiation into an electric signal are arranged in rows and columns; a drive circuit unit for driving said conversion unit; a signal processing circuit unit for reading the electric signal from said conversion unit; a radiation detecting unit for detecting irradiation or non-irradiation of said radiation; and a controller for controlling operation of said drive circuit unit and operation of said signal processing circuit unit, wherein said controller selectively carries out a first read operation of reading an electric signal based on the radiation from said conversion unit and a second read operation of reading an electric signal not based on the radiation from said conversion unit, and controls operation of said drive circuit unit and said signal processing circuit unit such that, when the irradiation of the radiation is detected by said radiation detecting unit during the second read operation, the second read operation is stopped, and when the non-irradiation of the radiation is detected by said radiation detecting unit, the first read operation is started.