A radiation tube includes an enclosure having an opening portion, an electron source disposed inside the enclosure, a target unit configured to generate radiation by being bombarded with electrons emitted from the electron source, and a front shield disposed on the opening portion and joined to the target unit. The front shield has a slit-shaped opening that shields some of the radiation radiated from the target unit. The radiation is radiated through the opening in the shape of a fan beam.

A target for an x-ray tube can emit x-rays in response to impinging electrons. Some electrons rebound without interacting atomically to form x-rays. Problems of these non-interacting electrons include reduced x-ray flux, charging electrically-insulative components of the x-ray tube, and misdirecting the electron beam. The target can include an array of holes, an array of posts, or both. The holes/posts can increase electron interaction with material of the target. Consequently, a higher percentage of impinging electrons can form x-rays. The holes/posts can also allow the target to effectively generate x-rays of different energies by providing a target with multiple thicknesses. X-rays can be generated in thicker regions of the target with the x-ray tube operated at a larger voltage. X-rays can be generated in thinner regions of the target with the x-ray tube operated at a smaller voltage.

An X-ray tube with an anode assembly and specially designed heat transfer element is described. The anode assembly includes an X-ray producing target and a substantially cylindrical electrode that stops or inhibits electrons that may back-scatter from the target. At least one heat transfer element is positioned proximate the anode assembly and in the region between a conducting enclosure and a non-conducting hollow housing or tube. The heat transfer element is positioned to thermally couple the hot anode assembly to an air-cooled conducting enclosure while maintaining an electric isolation.

The X-ray analysis apparatus contains an X-ray generation unit. The X-ray generation unit includes a target plate having a target that is irradiated with an electron beam from an electron beam source and generates X-rays, X-ray convergence optics that converges X-rays generated from the target in conjunction with a movement of the target plate, and a driving unit that changes a position of the target plate or the X-ray convergence optics relative to the electron beam source.

Described herein is a medical linear accelerator including an accelerator target structure constructed of a material having a thickness of less than 0.2 radiation lengths, and an accelerator structure to receive an electromagnetic wave and generate an output therapy dose rate of electrons having a beam energy between 4-25 mega-electronvolts (MeV).

A target assembly for generating radiation may comprise a target, a substrate and a window. The target may be capable of generating first radiation when impinged by a beam. The window may be at least partially permeable to the beam. The window and the substrate may form at least part of a hermetically sealed chamber and the target may be positioned in the chamber. The chamber may be filled with air having a normal or reduced content of oxygen.

An x-ray tube includes an electron emitter to emit an electron beam; and a multilayer anode including a first anode layer facing the electron beam and a second anode layer facing away from the electron beam. The first anode layer includes a first anode material to generate a braking radiation via the electron beam and the second anode layer includes a second anode material to generate a further x-ray radiation via the braking radiation. The further x-ray radiation is relatively more monochromatic than the braking radiation and wherein the first anode layer and the second anode layer adjoin in a planar manner.

A method for imaging a sample by means of an X-ray detector is disclosed, including providing an electron beam interacting with a target to generate X-ray radiation emitted from an X-ray spot on the target, moving the sample relative to the target, deflecting the electron beam such that the X-ray spot is moved over the target simultaneously and in accordance with the movement of the sample, and detecting X-ray radiation emitted from the X-ray spot and interacting with the sample.

A planar filament 11.sub.f can include multiple materials to increase electron emission in desired directions and to suppress electron emission in undesired directions. The filament 11.sub.f can include a core-material CM between a top-material TM and a bottom-material BM. The top-material TM can have a lowest work function WF.sub.t; the bottom-material BM can have a highest work function WF.sub.b; and the core-material CM can have an intermediate work function WF.sub.c(WF.sub.t<WF.sub.c<WF.sub.b). A width W.sub.t of the filament 11.sub.f at a top-side 31.sub.t can be greater than its width W.sub.b at a bottom-side 31.sub.b (W.sub.t>W.sub.b). This shape makes it easier to coat the edges 31.sub.e with the bottom-material BM, because the edges 31.sub.e tilt toward and partially face the sputter target. This shape also helps direct more electrons to a center of the target 14, and reduce electron emission in undesired directions.

A monolithic housing for an x-ray source can wrap at least partially around a power supply and an x-ray tube. The monolithic housing can include Al, Ca, Cu, Fe, Mg, Mn, Ni, Si, Sr, Zn, or combinations thereof. Mg can be a major component of the monolithic housing. The monolithic housing can be formed by injection molding. The monolithic housing can provide one or more of the following advantages: (a) light weight (for easier transport), (b) high electrical conductivity (to protect the user from electrical shock), (c) high thermal conductivity (to remove heat generated during use), (d) corrosion resistance, (e) high strength, and (f) high electromagnetic interference shielding (to shield power supply components from external noise, to shield other electronic components from power supply noise, or both).