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An X-ray tube is a vacuum tube that converts electrical input power into X-rays. [1] The availability of this controllable source of X-rays created the field of radiography, the imaging of partly opaque objects with penetrating radiation. In contrast to other sources of ionizing radiation, X-rays are only produced as long as the X-ray tube is ...
The anode is the electrode at the bottom. A Crookes tube (also Crookes–Hittorf tube) [1] is an early experimental electrical discharge tube, with partial vacuum, invented by English physicist William Crookes [2] and others around 1869–1875, [3] in which cathode rays, streams of electrons, were discovered. [4]
Opacity is the measure of impenetrability to electromagnetic or other kinds of radiation, especially visible light. In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc. An opaque object is neither transparent (allowing all light to pass through ...
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Photomultiplier tubes ( photomultipliers or PMTs for short) are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. They are members of the class of vacuum tubes, more specifically vacuum phototubes. These detectors multiply the current produced by incident light by as ...
Cathode-ray tube. The only visible differences are the single electron gun, the uniform white phosphor coating, and the lack of a shadow mask. A cathode-ray tube ( CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. [2]
Electron beam computed tomography (EBCT) is a specific form of computed tomography (CT) in which the X-ray tube is not mechanically spun in order to rotate the source of X-ray photons. This different design was explicitly developed to better image heart structures that never stop moving, performing a complete cycle of movement with each heartbeat.
Especially when artificially produced, synchrotron radiation is notable for its: High brilliance, many orders of magnitude more than with X-rays produced in conventional X-ray tubes: 3rd-generation sources typically have a brilliance larger than 10 18 photons·s −1 ·mm −2 ·mrad −2 /(0.1%BW), where 0.1%BW denotes a bandwidth 10 −3 ω centered around the frequency ω.