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Since the launch of the first compact fluorescent lamps in the early 1980's, manufacturers have striven to make them smaller and in a style as close as possible to the pear-shaped incandescent lamps they are designed to replace. It was identified at an early stage that consumers were put off the idea of changing to compact fluorescent simply because their shape was unattractive, and most were too long to neatly fit inside incandescent luminaires. In addition the great weight of magnetically-ballasted lamps caused tall standard lamps to be unstable.
In the late 1990's a number of lamps were marketed having a diffusing pear-shaped cover to hide the unsightly internal fluorescent tubes of these lamps. While helping to improve the image of CFL's, these are still considerably larger than incandescent lamps and do not fit inside all luminaires.
This Dulux EL Classic, launched by Osram in 2000, is the first compact fluorescent lamp to have been marketed with precisely the same dimensions as the 60mm diameter pear-shaped incandescent lamp. As the photo of a special clear lamp shows, it contains a small U-shaped discharge tube. The light output is rather low however, with its 5-watt consumption delivering an output similar only to a 25W incandescent lamp. The ultra small electronic ballast inside the plastic base shows great promise for future designs, and a brighter equivalent should be produced within the next few years. The goal of producing a 60W-equivalent Compact Fluorescent lamp in GLS-shape has been met only in Japan where the 100V mains electricity supply greatly facilitates the design of smaller ballasts. Both Toshiba and Matsushita make 15W lamps with same dimensions as GLS. |