PURPOSE: To provide an electrodeless electric discharge lamp which can be easily started.
CONSTITUTION: An inductive coil 2 is wound on the outer periphery of a bulb 1 sealed by electric discharge gas. A plurality of starting assisting electrodes 3a and 3b are arranged nearly on the whole periphery of the outer wall surface of the bulb 1, on the crossing line of the plane crossing at right angle with the center axis of the inductive coil 2 and the outer wall surface of the bulb 1. On start, the starting assising electrodes 3a and 3b are applied with high frequency voltage, and preliminary electric discharge is generated so as to be set in the winding direction of the inductive coil 2. When the inductive coil is applied with high frequency electric current in the state where the preliminary electric discharge is generated, a ring shaped inductive electric field set along the preliminary electric discharge is generated, and transition to the annular electric discharge is performed. Then, the electric discharge gas is excited to emit light.
WADA SEIGO
OKADA ATSUNORI
UKEKAWA MAKOTO
TOSAKA SHINGO
