Metal halide lamp with improved getter orientation

摘要

A metal halide discharge lamp has an ellipsoidal outer envelope with a quartz glass arc tube on its major axis supported by a frame having metal straps engaging pinched ends of the arc tube, which lie in a common pinch plane. An inert gas fill between the arc tube and the envelope establishes convection flow patterns during operation. Getters in the form of strips of ZrAl alloy are welded to the straps at 45° to the pinch plane on opposite sides thereof. The getter orientation improves absorption of impurities during horizontal lamp orientation, so that hydrogen spikes and other problems are eliminated.