"waste" heat?
Incandescent bulbs are certainly inefficient at producing lght, but who says the heat is waste? It was 2C outside last night, I'm fine with those bulbs adding to my home heating, the thermostat will adjust the central heating to compensate, nothing is "wasted".
As for while reflecting infrared energy back for reabsorbtion by the emitter., once "reabsorbed" where does it go? It can't stay in the emitting filament, since that would melt. Converting it to light would be nice, but materials which can absorb heat and generate light don't, AFAIK, exist.
Still at least you didn't copy the bit from the Daily Telegraph's "science editor" who described the incandescent filament as emitting black-body radiation...
Biting the hand that feeds IT
