To provide an X-ray tube in which an outer surface of a transmissive target is prevented from being oxidized and extraneous matter is prevented from being burnt on and attached to the outer surface.
An X-ray tube 10 includes an electron gun 11 and a vacuum case 12. The vacuum case 12 includes a case body 15 that accommodates the electron gun 11 therein, a transmissive target 16 that also serves as an X-ray window provided on the case body 15, and a flange 17 that protrudes from an outer surface of the case body 15 around the transmissive target 16. To the flange 17, a cap 28 can be attached for maintaining the outer surface of the transmissive target 16 either in a vacuum atmosphere or in a rare-gas atmosphere at the time of bake-out processing in a manufacturing process.
AOKI NOBUTADA
TOSHIBA ELECTRON TUBES & DEVIC
Satoshi Kabazawa
Tetsuya Yamada