Abstract: An object of the invention is to provide a high-resolution transmission type X-ray tube. With an X-ray imaging device according to the present invention, electron lens forming part 100A includes a central axis part 131, which is formed at the interior of a yoke 130, and an outer peripheral part 133, which defines the outer periphery of yoke 130. A part of a front end part 135 of central axis part 131 becomes a magnetic pole 110 that is positioned at the side of an electron gun. A first opening 111 is defined by magnetic pole 110. A part of a front end part 137 of outer peripheral part 133 becomes a magnetic pole 120 that is positioned at the side of a target 300. A second opening 121 is defined by magnetic pole 120. The value of diameter d2 of second opening 121 is greater than the value of diameter d1 of first opening 111.

Abstract: An object of the invention is to provide a high-resolution transmission type X-ray tube. With an X-ray imaging device according to the present invention, electron lens forming part 100A includes a central axis part 131, which is formed at the interior of a yoke 130, and an outer peripheral part 133, which defines the outer periphery of yoke 130. A part of a front end part 135 of central axis part 131 becomes a magnetic pole 110 that is positioned at the side of an electron gun. A first opening 111 is defined by magnetic pole 110. A part of a front end part 137 of outer peripheral part 133 becomes a magnetic pole 120 that is positioned at the side of a target 300. A second opening 121 is defined by magnetic pole 120. The value of diameter d2 of second opening 121 is greater than the value of diameter d1 of first opening 111.

Abstract: A hood electrode attached to a tip portion of a target is provided with an electron passage port widening on the side opposite from an x-ray emitting window, so that electrons emitted from an electron gun are made incident on the front end face of a target at a position on the x-ray emission side, whereby the distance between the x-ray generating position and the x-ray emitting window can be shortened.

Abstract: In an image intensifier comprising an entrance faceplate, made of a material transparent to light, having a photoelectric surface, formed on a surface opposite to a light entrance surface, for photoelectrically converting incident light into an electron; and an optical fiber block, constituted by a plurality of optical fibers bundled together, having a phosphor face at an end face of each optical fiber on the light entrance side, for emitting light in response to the electron incident thereon; the photoelectric surface of the entrance faceplate and the phosphor face of the optical fiber block opposing each other, while a vacuum atmosphere being formed therebetween; the optical fiber block is provided with a pit in which an end face of a core portion of each optical fiber is recessed from an end face of a cladding portion thereof, the bottom of the pit is filled with a phosphor, the surface of this phosphor is provided with a metal back layer, the cladding portion projects from the surface of the phosphor towa