Abstract: An electric lamp assembly includes an electrodeless lamp having a closed-loop, tubular envelope enclosing mercury vapor and a buffer gas at a pressure less than about 0.5 torr, a transformer core disposed around the lamp envelope, an input winding disposed on the transformer core and a radio frequency power source coupled to the input winding. The radio frequency source supplies sufficient radio frequency energy to the mercury vapor and the buffer gas to produce in the lamp envelope a discharge having a discharge current equal to or greater than about 2 amperes. The electrodeless lamp preferably includes a phosphor on an inside surface of the lamp envelope for emitting radiation in a predetermined wavelength range in response to ultraviolet radiation emitted by the discharge.