Some substances show up only when exposed to ultraviolet light, so this is done for substances that are not easily detected. In the process of police investigation, it is a typical application to use the purple light line to extract fingerprints.
The biggest manifestation of this role is in the anti-counterfeiting above, passports, train tickets, money will have a special ultraviolet fluorescent material composition of the picture, if the ultraviolet light irradiation, will show.
Ultra-high UV rays can successfully kill viruses in water and are used to disinfect water treatment in homes and public places such as schools and hospitals.
The action of violet lamp is very extensive, disinfect, medical treatment, detect, sterilize, background light, it is worth people to use well.