MERCURY-FREE CERAMIC METAL HALIDE LAMP WITH IMPROVED LUMEN RUN-UP

摘要

Disclosed herein are mercury free ceramic metal halide high intensity discharge lamps of specified arc tube geometry and composition of ionizable fill. Embodiments herein generally employ a discharge vessel formed of a ceramic material having an aspect ratio satisfied by 1 < ITL/ID < 4.5 where ITL is the inner total length of the discharge vessel and ID is the inner diameter of the discharge vessel. The ionizable fill typically comprises xenon at a cold fill pressure of from about 3 to about 15 bar, and a halide component comprising sodium halide, thallium halide and/or indium halide, and at least one rare earth halide. Disclosed advantages may include betterment in both lumen run-up and color shift upon dimming, as compared to mercury-containing CMH HID lamps.