X-ray detector with photo-gates and dose control

摘要

The invention relates to a radiation detector apparatus ( 10 ) with an array ( 12 ) of detector pixels. Each pixel ( 20 ) of the detector comprises a photogate electrode ( 21 ) under which electrical charges produced by incident radiation (v, X) are collected. The change of these charges gives rise to displacement currents in photogate lines ( 32 ) connected to the photogate electrodes ( 21 ) which may be monitored by current sensors ( 40 ). Thus the charges collected by all photogate electrodes ( 21 ) connected to a photogate line ( 32 ) can be measured during an ongoing exposure, allowing for advanced dose control methods of the illumination.