Abstract: Linear scanning x-ray apparatus generates a collimated fan beam which is moved together with a detector relative to a subject to generate a composite x-ray image of the subject. An adjustable collimator varies the width of the imaging beam in the scan direction. A control system responds to adjustment of the collimator to combine output signals of groups of two or more pixels in the detector, in order to optimize the contrast resolution of the image signals for a given spatial resolution. The invention provides a collimator for use in the apparatus.

Abstract: X-ray imaging apparatus is provided for generating a composite image of a subject by moving a radiation source (12) and a camera array (122) relative to the subject. A drive mechanism (22) generates clock signals which are used to synchronize the operation of the camera array with the movement thereof, and the composite image data which is generated is stored for display and further signal processing. Control means move the radiation source (12) and the camera array (122) according to the intensity of the imaging beam.