X-RAY SYSTEM WITH FIELD EMITTERS AND ARC PROTECTION

To inhibit a field emitter from being deteriorated or broken by arcing in an x-ray tube.SOLUTION: An x-ray tube comprises: a field emitter including an emission surface; an anode; and a focus electrode disposed between the field emitter and the anode. The focus electrode includes: a first surface that is substantially perpendicular to the field emitter emission surface and nearest to the field emitter; a second surface that is axially nearest to the anode, where the field emitter and the anode form an axis; a third surface that extends between the first surface and the second surface; and a first location on the focus electrode between the first surface and the third surface, the first location being farther from the anode than a second location on the focus electrode between the third surface and the second surface.SELECTED DRAWING: None 【課題】Ｘ線管における、アーク放電による電界エミッタの劣化、破壊などを抑制する。【解決手段】ｘ線管は、放出面を有する電界エミッタ、アノード、及び電界エミッタとアノードとの間に配置される集束電極を含み、集束電極は、電界エミッタの放出面に実質的に垂直であり、電界エミッタに最も近い第一表面と、軸方向でアノードに最も近い第二表面であって、電界エミッタ及びアノードが軸を形成する、第二表面と、第一表面と第二表面との間に延在する第三表面と、第一表面と第三表面との間の集束電極上の第一位置であって、第三表面と第二表面との間の集束電極上の第二位置よりもアノードから遠い、第一位置とを含む。【選択図】なし