Being the synthetic quartz glass which is used for the synthetic quartz glass for the vacuum ultraviolet ray optical component

摘要

PROBLEM TO BE SOLVED: To provide a synthesized quartz glass with a superior optical transparency at wavelength of 157 nm and an extremely superior uniformity of the optical transparency. SOLUTION: A synthesized quartz glass used for an optical member of an optical device provided with a light source of a fluorine laser with a dominant wavelength of 157 nm comprises having a predetermined absorption peak coming from an OH group in a wavelength range of 2,600 nm-3,000 nm, having an OH group content of less than 10 ppm in a range of used light, a difference between maximum and minimum content of the OH group in the range of used light being a value of ΔOH or less given by a predetermined equation; and not including reduction type of flaws substantially.