Abstract: An incandescent lamp containing a coiled filament within a vitreous envelope wherein the filament is supported at at least one point along its coil length by a refractory metal support wire one end of which is welded to a coil and the other end secured to the envelope wall by a glass bead. The support prevents filament sag during lamp operation and is especially useful with double-ended high intensity tungsten-halogen lamps having an elliptically shaped filament chamber with an infrared reflecting and visible light transmitting optical interference coating on the chamber.

Abstract: An electrically insulative base for an incandescent lamp is disclosed having a two-part construction with the individual base parts being joined together in butt-seal engagement along a horizontal plane transverse to the longitudinal lamp axis. Said base construction is especially useful in the tungsten halogen cycle lamps of the high wattage type requiring that a ceramic material be used and whereby the ceramic base parts are joined together before lamp assembly with a ceramic sealing material.