FILAMENT LAMP WITH IMPROVED PERFORMANCE

摘要

Reduced power consumption is achieved in a filament quartz lamp by encasing the filament in an inner envelope having an elliptical portion. An IR coating is provided on the outer surface of the elliptical portion to reflect selected wavelengths of the emitted light toward the filament. A fill gas is also maintained at a reduced pressure therein. A second or outer envelope defines a cavity with the inner envelope. It is filled with an inert gas to limit oxidation associated with the leads extending from the inner envelope. The outer envelope is sealed in the base portion, and the alumina silicate glass provides W protection. This lamp arrangement provides for decreased power consumption without adversely affecting the lumen output, lamp life, or dimensional characteristics of the lamp.