HIGH-PRESSURE DISCHARGE LAMP AND LIGHTING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a metal halide discharge lamp preventing erosion of a discharge container with a metal halide retained in the vicinity of an open end of a small-diameter tubular part of the discharge container with an electrode structure inserted and improving the light emitting characteristic and a lighting system using the discharge lamp. SOLUTION: The high-pressure discharge lamp is within a range of 1.9(mm)≤Y-X≤5.0(mm) wherein X(mm) is a maximum outer diameter of an arc tube 1A made of heat-resistant translucent ceramics and a power supply conductor 34 and Y(mm) is an inner diameter of the discharge container 2 in a direction orthogonal to the end part P facing the side of an inflated part 21 of the power supply conductor 34 and within a range of 2.5(mg/cm3)≤M/V≤5.5(mg/cm3) wherein M(mg) is a total filling amount of a rare earth metal halide and V(cm3) is a content volume of the discharge container 2. COPYRIGHT: (C)2011,JPO&INPIT