Abstract: Row variable offsets in a large area solid state x-ray detector are compensated for. Initially, a calibration is performed to determine the row variable offsets. The calibration is achieved by measuring the average offset of each row. During normal operation, this offset is compensated for in a converting circuit. The required signal range of the converting circuit is consequently reduced.

Abstract: A brightness detector is used to control the x-ray exposure and the displayed image level in a diagnostic x-ray imaging system. Initially, a region of interest of an image is specified. The average pixel value within the specified region of interest of the image is then found, ignoring regions below a preselected low signal level threshold. Finally, the average pixel value is fed back to the x-ray generator to control the x-ray exposure. The average pixel value is also used to determine a scaling factor to be applied to the image in order to maintain an optimum brightness level when the desired x-ray exposure cannot be attained.