<Li> 1986 The "White" SON sodium vapor lamp is introduced . </Li> <Li> 1991 Philips invents a fluorescent lightbulb that lasts 60,000 hours . The bulb uses magnetic induction . </Li> <Li> 1992 - 94 a team at Nela Park, Cleveland, GE, with Jack Strok, creates ceramic metal halide lamps (CMH). Philips follows under W.de Kock and calls their versions CDM Ceramic Discharge Metal . Sales begin 1994 . This technology improves to be a superior lighting technology with up to 150 lm / W with good color rendering and 20.000 h life with very high lumen maintenance </Li> <Li> 1994 T5 lamps with cool tip are introduced to become the leading fluorescent lamps with up to 117 lm / W with good color rendering . These and almost all new fluorescent lamps are to be operated on electronic ballasts only . </Li>

When were light bulbs first used in homes