Radiation image pickup apparatus, radiation image pickup system, their control method and their control program

A control method of a radiation image pickup apparatus for photographing a radiation image comprising:

• a first reading step of reading a first signal value from a detection unit with a reading circuit by driving the detection unit irradiated by radiation with a driving circuit, the detection unit including a plurality of conversion elements, which are two-dimensionally arranged and convert the radiation into charges;
• a second reading step of reading a second signal value from the detection unit with the reading circuit by driving the detection unit with the driving circuit without being irradiated by any radiation before said first reading step;
• a third reading step of reading a third signal value from the detection unit with the reading circuit by driving the detection unit with the driving circuit without being irradiated by any radiation after said first reading step;
• and
• a step of subtracting a signal value acquired by the second signal value and the third signal value from the first signal value with a signal processing unit processing the electric signal output from the reading circuit, wherein there is subtracted, from the first signal value, the signal value derived by adding together the second signal value and the third signal value with weighting according to a frame rate of the photographing.

A computer-readable storage medium encoding, in executable form, a program for making a computer control an operation of a radiation image pickup apparatus for photographing a radiation image provided with a detection unit in which a plurality of conversion elements converting a radiation into charges is two-dimensionally arranged, a driving circuit driving the detection unit, a reading circuit for reading an electric signal based on the charges from the detection unit, and a signal processing unit processing the electric signal output from the reading circuit, wherein

• said program makes the computer selectively execute a first reading procedure of reading a first signal value from the detection unit with the reading circuit by driving the detection unit irradiated by the radiation with the driving circuit, a second reading procedure of reading a second signal value from the detection unit with the reading circuit by driving the detection unit with the driving circuit without being irradiated by any radiations before said first reading procedure, and a third reading procedure of reading a third signal value from the detection unit with the reading circuit by driving the detection unit with the driving circuit without being irradiated by any radiations after said first reading procedure, and
• said program makes the computer execute a procedure of subtracting a signal value acquired by the second signal value and the third signal value from the first signal value with the signal processing unit, wherein the signal processing unit subtracts, from the first signal value, the signal value derived by adding together the second signal value and the third signal value with weighting according to a frame rate of the photographing.