Fluorescent lamps having improved lamp spectral output and maintenance and method of making same

摘要

Lumen maintenance and spectral output of fluorescent lamps is improved by applying over the phosphor a vapor deposited film consisting of yttrium oxide and at least one activator. The vapor is generated by electron beam bombardment of the activated yttrium oxide target and the film is most efficacious when applied to a thickness of from about 0.2 microns to about 1.5 microns.