Patent ID: 6282263
Filing Date: 2001-08-28
Classification: G21K,H01J

Abstract:
X-ray generator comprising an electron gun, an X-ray tube, an electron focusing means and a stigmator, said X-ray tube comprising a target adapted to have an X-ray source formed thereon and an X-ray exit window of a material of low X-ray absorption, characterised in that:the X-ray tube is evacuated and sealed;the X-ray tube has a narrow portion having a tubular side wall;the stigmator is positioned between the electron focusing means and the target;the electron focusing means is arranged outside the X-ray tube around the narrow portion of the X-ray tube and is adapted to focus electrons from the electron gun to produce a stationary X-ray source on the target having a spot or line focus with a respective diameter or width less than 100 .mu.m;the electron focusing means comprises an x-y deflection system for centring the X-ray source; andthe X-ray exit window is located in the tubular side wall adjacent to the target to allow close coupling of an X-ray focusing device outside the sealed X-ray tube adjacent to said window.