THERMIONIC EMISSION
These negatively charged electrons come out of the metal to form a space charge. This space charge no longer allows other electrons to flow out of the metal surface until they are given enough thermal energy to On resistance to space charge. By this space charge, preventing other electrons from coming out of the metal surface is called Space Charge Effect.
When the electrons come out of the filament, the filament absorbs positive charge, so that the filament attracts some electrons again from this space charge. In this way, when the filament is heated to this Emission Temperature, a equilibrium is formed in which the number of electrons emitted from the filament is the same as the number of electrons absorbed by the filament. Due to which the number of electrons in the space charge is fixed, the number of which depends on the temperature of the filament. Thus a very large number of electrons can be obtained by accelerating a large number of electrons from the cathode to the anode. These electrons can be obtained. Beams always flow in the same direction (from cathode to anode) in the x-ray tube. In this electron beam, the repulsion force acts due to the same charge between the electrons of the electrons, due to which the electron beam spreads in its width, as a result it collides on a very large part of the x-ray tube. The foxing cups are used to prevent this dispersion of the electron beam and to limit the collision area of the electron beam at the anode. This forcing cup is given a minus potential equal to the filament| It is designed in such a way that it converts the electron beam to the desired shape and size on the target. This forcing cup is usually made of nickel. The x-ray tube usually has one filament and the modern x-ray tube has two filaments. Dual filament X-ray tubes have two filaments arranged in a Side by Side or One Above Other arrangement. They have one filament larger than the other. They are used to generate only one filament electron beam at a time. Large filament is for long exposure. You can see the filament by removing the filter from the beam exit port of the x-ray tube as the filter appears red after heating. The modern x-ray machine also has more than two (3) filaments and the filaments in the stereoscopic angiographic tube are in a different arrangement, in which two filaments are located at a distance of 4 cm, in which a stereoscopic film foot is removed from the exposure.
When a metal is
heated, its molecules (Atom) take thermal energy. Some of its electrons take up
so much energy that it can go away from the surface of the metal. These are
called Thermions. Without this energy, electrons can only move inside the metal
and cannot come out.
Thus, the arrival
of electrons with thermal energy in this way is called Thermionic Emission. In
this way, the accumulation of electron flakes on the metal surface in the form
of electron clouds is called Edison Effect.
These negatively charged electrons come out of the metal to form a space charge. This space charge no longer allows other electrons to flow out of the metal surface until they are given enough thermal energy to On resistance to space charge. By this space charge, preventing other electrons from coming out of the metal surface is called Space Charge Effect.
When the electrons come out of the filament, the filament absorbs positive charge, so that the filament attracts some electrons again from this space charge. In this way, when the filament is heated to this Emission Temperature, a equilibrium is formed in which the number of electrons emitted from the filament is the same as the number of electrons absorbed by the filament. Due to which the number of electrons in the space charge is fixed, the number of which depends on the temperature of the filament. Thus a very large number of electrons can be obtained by accelerating a large number of electrons from the cathode to the anode. These electrons can be obtained. Beams always flow in the same direction (from cathode to anode) in the x-ray tube. In this electron beam, the repulsion force acts due to the same charge between the electrons of the electrons, due to which the electron beam spreads in its width, as a result it collides on a very large part of the x-ray tube. The foxing cups are used to prevent this dispersion of the electron beam and to limit the collision area of the electron beam at the anode. This forcing cup is given a minus potential equal to the filament| It is designed in such a way that it converts the electron beam to the desired shape and size on the target. This forcing cup is usually made of nickel. The x-ray tube usually has one filament and the modern x-ray tube has two filaments. Dual filament X-ray tubes have two filaments arranged in a Side by Side or One Above Other arrangement. They have one filament larger than the other. They are used to generate only one filament electron beam at a time. Large filament is for long exposure. You can see the filament by removing the filter from the beam exit port of the x-ray tube as the filter appears red after heating. The modern x-ray machine also has more than two (3) filaments and the filaments in the stereoscopic angiographic tube are in a different arrangement, in which two filaments are located at a distance of 4 cm, in which a stereoscopic film foot is removed from the exposure.
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