Are high intensity discharge lamps that are among others filled with metal halides. MH lamps are particularly suited for growing of plants.
They are the successors of high-pressure mercury lamps, which emit a bluish light without the use of fluorescent substances. Metal halide lamps are relatively compact. They consist of an inner balloon of quartz glass or ceramic, such as aluminum oxide, in which the actual gas discharge takes place. The inner balloon is surrounded by an outer balloon made of glass for protection and to absorbe the UV radiation from the gas discharge.
The metal halide lamps are also used to illuminate sports fields and stadiums. In recent years, they are also often used for shop window lighting, high (factory) halls and at petrol stations. Characteristic is the bright white light.