Sensitivity is freely changeable to another one in correspondence to a
photographing mode, and both still image photographing and moving image
photographing for example which are largely different from each other in
dosage of exposure to radiation and which are also different from each
other in required sensitivity are carried out so as to meet that request.
A source or drain electrode of a TFT 21 is connected to a signal output
circuit 3 through a signal line 14a and an IC 5. A source/drain of a TFT
23 is connected to the signal output circuit 3 through a signal line 14b
and the IC 5. Thus, in each pixel 6, any one of the signal lines 14a and
14b is freely selectable when a signal is read out.