Patent ID: 9368339
Filing Date: 2016-06-14
CPC Classification: H01J

Claim Text:
1. A discharge lamp, comprising: a discharge vessel defining a sealed inner discharge space therein, the discharge space comprising an elongated central portion having an internal cross-sectional diameter (ID); and a first electrode and a second electrode, each projecting into said discharge space, an outerwall of the discharge vessel comprising a first groove where the first electrode is embedded, and a second groove where the second electrode is embedded, the first and second grooves configured to have a groove distance (RA) therebetween, wherein the said discharge space is charged with a rare gas and a metal halide composition, the metal halide composition being substantially free of mercury, such that when an arc discharge is formed between said first and second electrodes, the metal halide composition is at least partly evaporated, and after the arch discharge ceases, the metal halide composition forms a film on an inner wall of said discharge vessel, the film having a surface area (A wherein the metal halide composition is charged into the discharge space in an amount such that a matching quotient (Q) having the formula: is greater than or equal to 2.