X-ray is an electromagnetic wave with extremely short wavelength and high energy. The wavelength of X-ray is shorter than that of visible light (about 0.001 to 100 nanometers, and the wavelength of X-rays used in medicine is about 0.001 to 0.1 nanometers). Its photon energy is tens of thousands to hundreds of thousands times larger than that of visible light.
1. Penetration: Because of its short wavelength and high energy, X-rays are only partly absorbed by the substance when irradiated on the substance, and most of it is transmitted through the atomic gap, showing a strong penetrating ability. The ability of X-rays to penetrate matter is related to the energy of X-ray photons. The shorter the wavelength of X-rays, the greater the energy of the photons and the stronger the penetrating power. The penetrating power of X-rays is also related to the density of the material. The use of this property of differential absorption can distinguish materials with different densities.
2. Ionization: When a substance is irradiated by X-rays, it can cause extranuclear electrons to depart from the atomic orbit to produce ionization. The amount of ionized charge can be used to determine the amount of X-ray exposure. According to this principle, an X-ray measuring instrument is made. Under the action of ionization, gas can conduct electricity; certain substances can undergo chemical reactions; various biological effects can be induced in the organism.
3. Fluorescence effect: X-ray wavelength is very short and invisible, but when it irradiates certain compounds such as phosphorus, platinum barium cyanide, zinc cadmium sulfide, calcium tungstate, etc., it can cause the substance to fluoresce (visible light or ultraviolet). The strength of is proportional to the amount of X-rays. This effect is the basis for the application of X-rays in fluoroscopy. Using this fluorescent effect can be used to make a fluorescent screen, which can be used to observe the image of X-rays passing through human tissue during fluoroscopy. It can also be made into an intensifying screen to enhance film during photography. Sensitivity.
4. Heat effect: Most of the X-ray energy absorbed by the substance is converted into heat energy, which raises the temperature of the object.
5. Interference, diffraction, reflection, and refraction effects: these effects have been applied in X-ray microscopy, wavelength measurement and material structure analysis