Image sensing apparatus and method using radiation

A radiation image sensing apparatus for sensing a radiation by a sensing unit and outputting an electric signal corresponding to the sensed radiation, said sensing unit comprising:

• an insulating substrate;
• a conversion section arranged over the insulating substrate and, configured to have a first semiconductor conversion element for converting the radiation into an electrical signal and a switch element connected to the first semiconductor conversion element;
• a second semiconductor conversion element arranged over the insulating substrate, configured to convert the radiation into an electrical signal for detecting a dose of the radiation incident on said conversion section;
• and
• a bias line which is connected to a first electrode arranged for said first semiconductor conversion element and a second electrode arranged for said second semiconductor conversion element, and at least one of the first electrode and the second electrode includes a transparent electrode layer,
• wherein a first pixel region, which includes the first semiconductor conversion element and the second semiconductor conversion element, and a second pixel region, which includes the first semiconductor conversion element and no second semiconductor conversion element, are arranged on the insulating substrate,
• the size of the first pixel region is substantially equal to that of the second pixel region, and
• a light-receiving area of the first semiconductor conversion element in the first pixel region is smaller than that of the first semiconductor conversion element in the second pixel region.