Fluorescence is one of the ways to convert electrical energy into light. Lamps based on this principle have four basic components: a transparent glass tube, two electrodes (one at each end), a mixture of gases and a material that coats the tube internally. When we turn on the switch, the electrodes generate an electric current that, when passing through the gaseous mixture – argon and mercury vapour, for example – emits ultraviolet radiation. The UV light is then absorbed by magnesium tungstate or zinc silicate, the materials most commonly used for lining the inside of the tube. These substances have the property of transforming the invisible ultraviolet wavelength into visible light, which is reflected to the environment. The fluorescent lamp is more economical than the incandescent lamp, as it heats up less and dissipates less energy in the form of heat.
1. The electrodes generate an electric current that stirs the argon molecules and mercury vapor, stimulating the emission of ultraviolet rays
2. UV radiation is absorbed by the tube’s inner coating, with a special chemical composition that transforms it into white light