US Patent 7543957 Thermal management of LEDS integrated to compact fluorescent lamps

A light-source assembly includes a low-pressure fluorescent discharge tube arrangement having a cold spot temperature and radiating white light and at least one light-emitting diode radiating red light. An operating circuit supplies current to the discharge tube arrangement and the light-emitting diode. An outer envelope surrounds at least the discharge tube arrangement and provides a substantially homogenous light resulting from a mixture of the light radiated by the discharge tube arrangement and the light radiated by the light-emitting diode. A base mechanically and electrically connects at least the discharge tube arrangement in the outer envelope to a lamp-holder.