Future of incandescent and tungsten-halogen lamps

Development of the tungsten-halogen lamp has produced a wide range of light sources with a higher luminous efficacy and longer life than conventional incandescent lamps, but ultimate failure is still filament burnout caused by the formation of hot spots. Recent research has been directed towards reviewing other means of securing further improvements and has included alternative materials infrared reflecting coatings and the application of double quantum phosphors. However, the major area of progress has been in the development of tungsten-halogen lamps with a selfhealing regenerative cycle to delay the formation of hot spots. Experimental lamps have already been made that have double the life of established tungsten-halogen counterparts.