摘要 |
An incandescent lamp having a transparent heat mirror placed on the lamp envelope which transmits a substantial portion of the energy in the visible range produced by the lamp filament and which reflects back to the filament at least about 80%-85% of the infrared energy that the filament produces. In the preferred embodiment the transparent heat mirror is formed by a layered coating of TiO2/Ag/TiO2 optimized for the operating temperature range of the filament. The filament is constructed to optically conform to the shape of the lamp envelope. |