DC operated filament lamp - has built in rectifier and is operated in DC mode with rectification from AC supply

摘要

An electric lamp with a built in rectifier allows the filament to be energised with a d.c supply, while coupled to the a.c mains. Experimental tests indicate that while the filament is subjected to a higher voltage with some 70% increase in current drawn, the developed illumination is increased by 170%. As a result of operating on a d.c. supply, the filament exhibits a greater load carrying capacity resulting in an improved operational life. In addition to the built-in rectifier is a transformer to allow the lamp to be operated at a lower voltage.