X-ray diagnostic apparatus for producing transverse layer images

Abstract

In an illustrated embodiment, a ring-shaped X-ray source is operative to supply a fan-shaped X-ray beam from an incremental region thereof, successive incremental regions being sequentially activated to change the angular relationship between the beam and the subject. By way of example, three incremental regions equally spaced about the source ring may be simultaneously activated and then shifted in synchronism with the rotation of a collimator ring such that openings in the collimator ring are continually aligned with the active source regions, and collimator blades are continuously aligned with the active source regions so as to supply transmitted rays from each source region to a series of stationary detector elements. In the illustrated embodiment, the X-ray source regions and a detector ring are laterally offset from each other, and a diaphragm arrangement directs each beam at a slight angle so as to laterally bypass the adjacent portion of the detector ring while impinging on the receiving detectors. Motion of the collimator ring may be utilized to control shifting of the X-ray beams, so that such shifting is precisely synchronized with the movement of the collimator ring.