High pressure sodium vapor discharge lamp

摘要

A high pressure sodium vapor discharge lamp, characterized in that its discharge tube contains xenon gas at a high pressure of e.g. over 150 torr, at least one of discharge electrodes has a projection conductor which is disposed extending therefrom towards an inside surface of a side wall of a tube envelope of the discharge tube in a manner that outer end of the projection conductor is disposed in proximity to a side wall of said tube envelope with a predetermined gap in-between and a starting aid conductor is disposed lengthwise on the outside surface of the side wall, and connected to the other electrode.