Patent ID: 8164239

Claim:
An excimer lamp comprising: a discharge vessel made of silica glass that allows the passage of vacuum ultraviolet radiation having a discharge space, a pair of electrodes, provided on the silica glass at each of opposite sides of the discharge vessel in a manner causing the discharge vessel to function as a dielectric and an excimer discharge producing ultraviolet radiation to be generated in the discharge space of said discharge vessel, and an ultraviolet reflection film made of silica particles and alumina particles formed on a surface of the discharge vessel that is exposed to said discharge space; wherein the silica particles in the ultraviolet reflection film have a mean particle Feret's diameter that is at least 0.67 times as large as a mean particle Feret's diameter of the alumina particles in the ultraviolet reflection film; wherein the content of alumina particles in the ultraviolet reflection film is at least 5 wt % of the total weight of the silica and alumina particles.