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Charged particle excitation

High-energy particles, such as protons, alpha particles, and beta particles, can be used to excite certain phosphors, but they are not very useful in lighting except as indicator light sources. Beta lamps have some uses, such as filling a sealed glass shell with a fluorescent screen with tritium or krypton 85, which can be widely used on telephone dials, ship compasses, navigation marks, and other luminous indicator marks that have not been maintained for many years.

Using a low-energy electron beam to excite the fluorescent screen in a cathode ray tube can be used for display equipment, especially for television picture tubes.

The energy of a radioactive light source is very high, but it cannot change, and the incident density of radiation is also small, while cathode rays, on the contrary, can transfer more energy to the luminescent material. Because it contains more particles with less energy, the luminescent material is less likely to deteriorate under bombardment, so the light output is also better. For example, the light efficiency of the black and white cathode ray tube screen of a television receiver is about 40 lumens/watt (when using highly transparent glass). Most display devices or cathode ray tubes for televisions must use fluorescent materials with very short afterglow (i.e., fast decay), but the ray tubes on radars are required to produce phosphorescence on the fluorescent screen, or a more persistent light emission, so that the object trace can be observed for a longer time.

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