ABSTRACT

High power (100 — 300 W) and long life electrodeless fluorescent lamps operating at frequencies of f = 0.250 — 2.65 MHz have been recently introduced into market [1,2]. To achieve high luminous efficacy, the lamps employ ferrite cores made from low loss material. However, the use of a ferrite core requires a cooling structure to keep the core at below Curie point temperatures that increases the lamp manufacturing cost. In this paper we present design and characteristics of an electrodeless fluorescent lamp made of a single glass tube with an induction coil of few turns. The lamp operated at frequencies of 0.300 — 15 MHz and powers of 50 — 200 W does not employ ferrite core nor cooling structure while providing high light output with efficacy of 76 — 86 LPW.