Seen from the intrinsic quality and characteristics, x ray is an invisible light with all the characteristics of light and undulatory property and corpuscular property. The former is characterized by wavelength and frequency; the latter is characterized by energy, momentum and mass. In addition to the above-mentioned commonality, because x-ray has shorter wavelengths and higher photon energies, its wavelengths is shorter than that of visible (about 0.001~100 nm, and medically applied x-ray wavelengths are 0.001~0.1 nm). ); its photon energy is tens of thousands to hundreds of thousands times greater than the photon energy of visible light. At the same time, it also has physical effects, chemical effects and biological effects.
Fixed-anode x-ray tube
Composition of x-ray tube
It consists of three parts: an anode, a cathode and a glass envelope.
- Function
The role of the anode is to generate x-rays, dissipate heat, absorb secondary electrons and scattering x-rays. The role of the cathode is to emit electrons and focus to make the electron beam hitting on the target surface have a certain shape and size for forming x-ray spots. and the filament is to emit electrons.
- Working principle
Electrons emitted by the cathode are emitted as electron beams to the surface of the anode target by focusing to generate x-rays.
Rotating anode x-ray tube
- Structure
Rotating anode x-ray tube consists of three parts: the anode, the cathode and the glass envelope. Compared with fixed anode x-ray tube, it mainly differs in anode structure. The anode part is composed of a target rotor, a rotating shaft, a bearing and a stator.
- Principle
Electrons emitted from the cathode deviating from the central axis of the tube bombard on the rotating anode target surface to form x-rays. Since the heat is evenly distributed on a rotating toroidal surface, the heat in the unit is greatly reduced, thereby the power of the x-ray tube is highly increased.
Here, regarding special x-ray tubes, such as three-pole x-ray tubes, x-ray tubes for soft tissue photography, etc., will not be introduced one by one. There are only difference because of different using occasions, but the principle is basically the same.
