X-RAY TRANSMISSION SCANNING SYSTEM AND METHOD AND ELECTRON BEAM X-RAY SCAN TUBE FOR USE THEREWITH

摘要

Disclosed is a multiple target scanning electron beam X-ray source for use in high speed multiple section computed-tomographic (CT) X-ray transmission scanners. The scanner uses a single electron beam tube. The electron beam is rotated by a magnetic deflection system. The electronic scanning system is much faster than mechanical scanners and requires no moving parts that require high precision and alignment. It also eliminates elaborate systems of sliding electrical contacts. The system includes an electron beam scan tube having a cylindrical end portion with an electron gun and a semi-circular portion. The electron beam is focussed and bent to direct it into the semicircular portion and scan it in a semi-circular over X-ray generating target rings. Collimators adjacent the target rings provide a fan-shaped X-ray beam which rotates as the electron beam is moved along the target rings.