Electrodeless HID Lamps Excited by Circularly-Polarized Microwave Discharges

摘要

We have developed, to our knowledge, the first commercial-class electrodeless HID (ELS-HID) lamp system using a nonrotating bulb excited by circularly-polarized microwave discharges of InBr vapor at atmospheric pressure. Unlike conventional high pressure "electrodeless HID lamps"—a more generic term for the well-known electrodeless sulfur lamp—the bulb in our lamp system is stationary. The microwaves at 2.46 GHz are circularly polarized in TE_(11) mode by a specially designed polarizer, making the gaseous discharges themselves rotate in the stationary bulb that is placed in a circular cavity. The ELS-HID SolaRay lamp system generates white light of an unoptimized luminous efficacy of 65 lm/W_[wall-plug] with an input power of 1.1 kW and of a color rendering index in excess of 96 Ra. This ELS-HID lamp system has a number of other distinctive features, including a significant change in the spectrum as the input power is varied.