High pressure discharge lamp and method of production therefor

摘要

A high pressure discharge lamp includes a quartz glass bulb and a pair of electrodes. Each electrode of the pair of electrodes is disposed so as to be opposite the other in the quartz glass bulb. The quartz glass bulb of the high pressure discharge lamp contains at least mercury and a halogen gas which are airtightly sealed in the quartz glass bulb. The partial pressure of oxygen (O) in the quartz glass bulb is about 2.5x10<-3 >Pa or less and the partial pressure of the halogen gas in the quartz glass bulb is in the range between about 1x10<-6 >mumol/mm<3 >and 1x10<-8 >mumol/mm<3>. The pair of electrodes contain potassium oxide in the range between about 20 ppm and 40 ppm.