High-intensity discharge lamps also known in the industry as HID lamps are a type of electrical gas-discharge lamp. Producing light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tube.
Brand new high-intensity discharge lamps make more visible light per unit of electric power consumed than fluorescent and incandescent lamps, since a greater proportion of their radiation is visible light in contrast to infrared. Many modern vehicles use HID bulbs for the main lighting system.
