The starting property of inductively coupled electrodeless metal halide lamps was evaluated and analyzed. The effects of the lamp parameters and of the circuit parameters on the starting property were investigated. Method was established for measuring the starting property that uses twoindependent RF power supplies, one for the break down circuit and one for the induction-coil circuit.
The evaluated lamp parameters were type and pressure of filled rare gas, gaps between arc tubes and induction coil, voltage applied to starting-aid discharge tube, and waveform of voltage applied on starting-aid discharge tube. Additionally, the effects of the free iodine gas and the time to become ready for restart were evaluated.
The evaluated circuit parameters were, the phase difference between the voltage applied on the starting-aid discharge tube and the induction-coil terminal voltage, and the waveforms (flat and ripple outline, RF modulated) of the induction coil voltage.
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