| 摘要 |
<p>An X-ray detector apparatus has an array of pixels arranged into a plurality of sub-arrays ( 40 ). The pixels in each sub-array ( 40 ) share a common output ( 42 ). The detector is operable in two modes, a dose sensing mode in which a switching arrangement ( 50 ) is turned off and charge flow in response to incident radiation is partially coupled through an off-capacitance of the switching arrangement ( 50 ) to the output, and a read out mode in which the switching arrangement is turned on to allow charge to flow between the charge storage element and the output ( 42 ) for measurement as a detection signal. The switching arrangement ( 50 ) is turned on by first and second control signals to enable a single pixel within the sub-array ( 40 ) to be selected. Thus, the resolution of normal read out is per-pixel whereas the resolution of dose sensing is per-sub-array.</p> |
