Patent ID: 7298826

Claim:
An X-ray generator comprising: an X-ray tube comprising: a vacuum enclosure ( 20 ); an electron gun ( 23 ) provided in the vacuum enclosure ( 20 ) and emitting an electron beam in an electron beam direction; and an X-ray generating target ( 26 ) having an electron incident surface ( 27 ) onto which the electron beam emitted from the electron gun ( 23 ) enters; and an X-ray monitor ( 30 ) for receiving the X-rays to monitor the received X-rays, wherein the vacuum enclosure has first and second exit windows which constitute a part of the vacuum enclosure respectively, wherein the vacuum enclosure ( 20 ) has a metal housing ( 21 ) in which the first ( 31 ) and second ( 24 ) windows are independently and respectively provided on the metal housing ( 21 ), wherein the electron incident surface ( 27 ) of the X-ray generating target ( 26 ) is provided within the metal housing ( 21 ); wherein the first ( 31 ) and second ( 24 ) windows are separated through a part of the metal housing ( 21 ); wherein an X-ray exiting direction of the X-rays through the first window and an X-ray exiting direction of the X-rays through the second window intersect each other, and wherein the X-ray exiting portion of the second window and the X-ray monitor ( 30 ) are positioned so that the X-ray exiting portion of the second window ( 24 ) and the X-ray monitor are in the vacuum enclosure side with respect to a plane ( 31 a ) of an exit surface of the first window ( 31 ), wherein the electron incident surface of the X-ray generating target is supported in an inner space of the metal housing without contacting the metal housing by a target support, the metal housing ( 21 ) has an electron gun storing portion ( 21 b ) which projects from a main body ( 21 a ) of the metal housing ( 21 ), a stem plate ( 24 ) made of ceramics is provided at an edge portion of the electron gun storing portion ( 21 b ), a stem pin ( 25 ) holding the electron gun ( 23 ) passes through the stem plate ( 24 ), the stem pin ( 25 ) holds the stem plate ( 24 ), the stem plate ( 24 ) functions as the second window ( 24 ) and faces to the X-ray monitor, and the X-ray monitor is positioned so that the X-ray monitor is in the vacuum enclosure side with respect to the plane ( 31 a ) of an exit surface of the first window ( 31 ).