X-RAY TUBE AND ITS CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To provide an X-ray tube with a stable minute beam dimension and to provide its control method. SOLUTION: The X-ray tube includes; a cathode releasing an electron beam, an anode accelerating the electron by voltage applied between it and the cathode; a first control grid installed between the cathode and the anode and carrying out current-control of the electron beam; a second control grid installed between the first grid and the anode and carrying out focus-control of the electron beam; and a target connected electrically with the anode and generating X-ray by collision of the accelerated electron beams. Spacing between an end part on the anode side of the second control grid and the cathode is two times or more but three times or less than the spacing between the end part and the anode. COPYRIGHT: (C)2008,JPO&INPIT