Surgical lights are designed to operate for prolonged periods without excessive heat radiation. For ceiling-mounted lights, one or more transformers are placed either above the finished ceiling or in a wall-mounted remote control box to convert incoming line voltage to the lower voltage necessary for most lights.
Conventional lights were usually gas-filled incandescent lamps containing a certain proportion of halogen in an inert gas with a pressure of more than 3 atmospheres (atm). Some gas-disch