Regenerative cycle incandescent lamp contg. mercuric bromide - in amt. correlated with design parameters to avoid premature blackening

摘要

The lamp, having predetermined life and efficiency ratings when operated at a selected voltage, comprises (a) a sealed radiation transmissive envelope contg. a W filament, (b) conductors extending through the envelope connected to the filament, (c) an inert fill gas and (d) 13-0.46 mu mole HgBr2/ml. envelope vol. to serve as a Br2 source for a W-Br cycle when subjected to heat and radiant energy from the filament during operation. The amt. of HgBr2 initially present and the quantity of Br2 provided during operation are correlated with the design life and efficiency ratins such that initial HgBr2 and resultant Br2 contents both increase as the efficiency rating increases and the design life rating decreases. The W-Br cycle established in the lamp inhibits discolouration and enhances the useful life of the lamp. High efficiency lamps are provided which meet or exceed their performance ratings.