Uses
Metal-halide lamps are used both for general lighting purposes both indoors and outdoors, automotive and specialty applications. Because of their wide spectrum, they are used for indoor growing applications, in athletic facilities and are quite popular with reef aquarists, who need a high intensity light source for their corals.
Metal-halide lamps are used in automobile headlights, where they are commonly known as "xenon headlamps" due to the use of xenon gas in the bulb instead of the argon typically used in other halide lamps. They produce a more intense light than incandescent headlights.
Another widespread use for such lamps is in photographic lighting and stage lighting fixtures, where they are commonly known as MSD lamps and are generally used in 150, 250, 400, 575 and 1,200 watt ratings, especially intelligent lighting.
3LCD and DLP video projectors use metal-halide lamps as their light source.
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