Energy-efficient compact screw-in fluorescent lamp

A compact fluorescent lamp has been designed and constructed which can replace an incandescent lamp. The lamp is slightly larger than a standard lamp (8 3/4 in. x 3 1/4 in.), but is designed to fit a majority of portable lamp applications. This version, with a core-coil ballast, results in a system efficacy of 54 lumens per watt, with a light output of more than 1800 lumens. This compares favorably with a 100-watt incandescent (17.5 lumens per watt and 1750 lumens light output). The color temperature of 30000K is compatible with an incandescent lamp (28000K). The color rendition index (CRI) is 84. With a solid-state ballast, the efficacy and light output could be increased by 20% (65 l/w, 2200 lumens) and could provide a direct replacement for a three-way, 150-watt incandescent lamp (15 l/w, 2200 lumens).