Search results
Results from the WOW.Com Content Network
Solid-anode microfocus X-ray tubes are in principle very similar to the Coolidge tube, but with the important distinction that care has been taken to be able to focus the electron beam into a very small spot on the anode. Many microfocus X-ray sources operate with focus spots in the range 5-20 μm, but in the extreme cases spots smaller than 1 ...
An illustration of the heel effect in an x-ray tube. In X-ray tubes, the heel effect or, more precisely, the anode heel effect is a variation of the intensity of X-rays emitted by the anode depending on the direction of emission along the anode-cathode axis. X-rays emitted toward the anode are less intense than those emitted perpendicular to ...
The first commercially made electronic TV sets with cathode-ray tubes were manufactured by Telefunken in Germany in 1934. [32] [33] In 1947, the cathode-ray tube amusement device, the earliest known interactive electronic game as well as the first to incorporate a cathode-ray tube screen, was created. [34]
Natural color X-ray photogram of a wine scene. Note the edges of hollow cylinders as compared to the solid candle. William Coolidge explains medical imaging and X-rays.. An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays.
In general, an X-ray's beam intensity is not uniform. When it focuses to a target, a conical shape appears (divergent beam). The intensity of the beam from the positive anode side is lower than the intensity from the negative cathode side because the photons created when the electrons strike the target have a longer way to travel through the rotating target on the anode side.
Electron gun from an oscilloscope CRT Setup of an electron gun. 1. Hot cathode.2. Wehnelt cylinder.3. Anode. A direct current, electrostatic thermionic electron gun is formed from several parts: a hot cathode, which is heated to create a stream of electrons via thermionic emission; electrodes generating an electric field to focus the electron beam (such as a Wehnelt cylinder); and one or more ...
During X-ray generation, surface electrons are released from a heated cathode by thermionic emission. The applied voltage (kV) accelerates these electrons toward an anode target, ultimately producing X-rays when the electrons are stopped in the anode. Thus, the kVp corresponds to the highest kinetic energy of the electrons striking the target ...
It consists of a gas-filled chamber with two electrodes; known as anode and cathode. The electrodes may be in the form of parallel plates (Parallel Plate Ionization Chambers: PPIC), or a cylinder with a coaxially located internal anode wire. A voltage potential is applied between the electrodes to create an electric field in the fill gas.