Precoated fluorescent lamp for defect elimination

摘要

A protective layer or precoat of a metal oxide for an internal conductive layer in a rapid-start fluorescent lamp is formed of yttria, ceria or silica to suppress the occurrence of localized appearance defects referred to as measles. The protective layer may be used in combination with conductive layers having a uniformly flat profile or a U-shaped bathtub profile to further enhance the suppression of measle defects. The lamp retains the desirable qualities of good startability and energy efficiency while at the same time avoiding the undesirable measle appearance defects.