Electrodeless high intensity discharge lamp having field symmetrizing aid

摘要

An electrodeless high intensity discharge (HID) lamp includes an electrodeless lamp capsule, first and second electric field applicators positioned so that the lamp capsule is between the electric field applicators, and a planar transmission line. The planar transmission line couples high frequency power from an input to the first and second electric field applicators and has a gap with in which the lamp capsule is positioned. A field symmetrizing conductor, preferably a thin wire, is located in an open side of the gap and is electrically connected to the ground plane of the planar transmission line. The field symmetrizing conductor is positioned such that the electric field in the lamp capsule is symmetrical with respect to the lamp axis and is colinear with the lamp axis.