MERCURY-FREE METAL HALIDE LAMP

摘要

The present invention provides a mercury-free metal halide lamp with an increased lamp operating voltage and prolonged lamp life without enclosing mercury or excessively increasing an inner pressure of an arc tube. A lamp in accordance with the present invention contains, as a content of a fill material 202, 0.04 mg of ScI3, 0.21 mg of NaI, 7 atm of Xe at room temperature, and 0.1 mg of YI3, which is an iodide of Y, Y having an ionization potential as a simple substance being 5 to 10 eV and a vapor pressure at a temperature of lamp operation being 10<-5> or higher. <IMAGE>