Patent ID: 8624991

Claim:
An apparatus comprising: a signal processing unit electrically connected to a detection unit, wherein the detection unit includes a plurality of pixels arranged in a matrix, each of the plurality of pixels is configured to convert radiation or light into an analog signal, the plurality of pixels are divided into at least a first pixel group and a second pixel group, the signal processing unit includes a first readout circuit configured to read an analog signal output from the first pixel group, a second readout circuit configured to read an analog signal output from the second pixel group, a first A/D converter configured to convert an analog signal from the first readout circuit into a digital signal, and a second A/D converter configured to convert an analog signal from the second readout circuit into a digital signal; and a control unit configured to perform processing on an A/D conversion characteristic of the first A/D converter, the processing being different from processing on an A/D conversion characteristic of the second A/D converter, on the basis of information regarding nonlinearity of the first A/D converter and information regarding nonlinearity of the second A/D converter.