PROBLEM TO BE SOLVED: To improve reliability and performance of a radiation generation unit 21 by employing a radiation generation tube 1 capable of obtaining a stable sealed state and simultaneously preventing electric fields from being concentrated due to a conductive joint material 13 protruded from a gap between joint surfaces, when joining electrodes 2, 4 and a tubular member 6 constituting a vacuum container 8 of the radiation generation tube 1.SOLUTION: In a radiation generation tube 1 employed by a radiation generation unit 21, electrodes 2, 4 include annular extending parts 16 extending from edges of the electrodes 2, 4 to a side of a tubular member 6, and an end portion of the tubular member 6 is inserted inside of the extending parts 16. A conductive joint material 13 is held between an end face of the tubular member 6 and surfaces of the electrodes 2, 4 opposing the end face, thereby joining both the electrodes 2, 4 and the tubular member 6. The conductive joint material 13 also enters between base-side inner peripheral surfaces of the extending parts 16 and an outer peripheral surface of the end portion of the tubular member 6 opposing the base-side inner peripheral surfaces. On the other hand, a gap between top-side inner peripheral surfaces of the extending parts 16 and the outer peripheral surface of the end portion of the tubular member 6 opposing the top-side inner peripheral surfaces is left as a void 15 in which the conductive joint material 13 is not held.COPYRIGHT: (C)2014,JPO&INPIT【課題】放射線発生管1の真空容器8を構成する電極2,4と管状部材6の接合において、安定した密閉状態を得ると同時に、接合面の間からはみ出した導電性接合材13による電界集中を抑制できるようにした放射線発生管1を用いることで、放射線発生ユニット21の信頼性及び性能を向上させる。【解決手段】電極2,4に、この電極2,4の周縁から管状部材6側に延出した環状の延出部16を設け、延出部16の内側に前記管状部材6の端部を差し込み、管状部材6端面と、この端面と対向する電極2,4の表面との間に導電性接合材13を挟み込んで両者を接合すると共に、延出部16の基部側内周面と、この基部側内周面に対向する管状部材6の端部の外周面との間にも導電性接合材13が入り込んでいる一方、延出部16の先端側内周面と、この先端側内周面に対向する管状部材6の端部の外周面との間は導電性接合材13が挟み込まれていない空隙15として残した放射線発生管1を用いた放射線発生ユニット21とする。【選択図】図1
