There are many kinds of things that emit luminous light, including natural and synthetic.
The main detectors are photoluminescence materials. When an object is irradiated by ultraviolet light, sunlight, or ordinary light, the object has a certain luminous performance in a dark environment, which is called a photoluminescence material. There are also called long afterglow luminescent materials and energy-storage luminescent materials. Their luminous intensity and the length of the delay are related to the material of the object. There are many kinds of photoluminescence materials, such as long phosphor fluorescent body and rare earth long afterglow fluorescent body. The long phosphor fluorescent body is a fluorescent body made of zinc sulfide and copper, the low cost of this kind of fluorescent body, but due to the unstable properties of sulfide, easy to moisture solution, poor anti-aging, short residual time and other shortcomings. Rare earth long afterglow fluorescent body is added to the base of aluminate fluorescent body with divalent rare earth europium and dysprosium made of long afterglow fluorescent body, fluorescence delay can reach more than 12 hours.