Abstract: A mercury vapor discharge fluorescent lamp having a barrier layer and a phosphor layer. The barrier layer comprises yttria-coated alumina particles. The barrier layer is preferably at least 11 weight percent yttria. Preferably the yttrium-coated alumina particles are provided in an aqueous suspension and are then substantially separated from the dissolved salts therein before being combined into a coating suspension for coating the lamp.

Abstract: A mercury vapor discharge fluorescent lamp having a barrier layer and a phosphor layer. The barrier layer comprises yttria-coated alumina particles. The barrier layer is preferably at least 11 weight percent yttria. Preferably the yttrium-coated alumina particles are provided in an aqueous suspension and are then substantially separated from the dissolved salts therein before being combined into a coating suspension for coating the lamp.

Abstract: A low pressure mercury vapor discharge lamp is provided, said discharge lamp (10) comprising an envelope (12) formed from light-transmitting material and containing an ionizable gas fill (22), mercury, and electrodes (18) sealed in the envelope. The envelope (12) is provided with a single layer coating (14) on the internal surface thereof next to the discharge space. The coating (14) contains halo-phosphate phosphor and 5-30 mass % aluminum oxide relative to the halo-phosphate phosphor, and the primary particle size of the aluminum oxide is smaller than 30 nanometers, the floc size of the aluminum oxide is smaller than 1 micrometer, and the void fraction of the total floc volume is at least 50%.

Abstract: An electrodeless fluorescent reflector lamp includes a housing arrangement having a threaded screw base for receiving line power and a lamp envelope mounted on the housing arrangement. A ballast circuit is disposed within the housing arrangement and is effective for converting line power into an RF signal which excites a fill contained within the lamp envelope to a discharge state thereby resulting in the production of visible light. The lamp envelope is constructed having an upper curved face portion and a lower tapered portion which extends partly within the housing. A reflective coating is applied to the lower tapered portion of the lamp envelope. A phosphor coating distribution is applied to the interior surface of the lamp envelope in a manner so as to maximize the light output from the reflector lamp.