X- or gamma-ray imaging method and apparatus with exposure time optimisation

摘要

The method involves using measurement pixels (11) to determine when the dose reaches a set value. Measurements on each pixel are halted and image pixels (10) are read to form the image. Charge collection is inhibited by deviating the electrons produced by sensor material (8) to an absorbent substrate so only the charges collected during the exposure time are stored. Alternatively the X-ray beam is stopped. An image is first created at a low dose value after which a second image is formed at the optimum dose value. When the final image is formed, the image is corrected for the missing pixels allocated for dose measurement.