Discharge lamp having light-transmissive conductive coating for RF containment and heating, and lamp assembly containing the same

摘要

A discharge lamp (12), such as a neon lamp or a subminiature fluorescent lamp, includes an elongated tubular lamp envelope (22) containing a fill material for supporting a light-emitting discharge and electrodes (24,26) mounted at opposite ends of the lamp envelope (22). A light-transmissive conductive coating (40) on the lamp envelope (22) substantially attenuates emission of RF energy. A conductor (44) in electrical contact with the conductive coating (40) couples the conductive coating (40) to a reference potential, such as ground. The conductor (44) may be a metal or conductive silicone strip in electrical contact with the conductive coating (40) along the length of the lamp envelope (22). The discharge lamp (12) may be connected to a ballast circuit (20) by coaxial cables (60,62). The outer conductor (66,70) of each coaxial cable (60,62) is connected to the conductive coating (40) to form a continuous RF shield. The conductive coating (40) and/or the metal strip may be used for heating of the discharge lamp (12).