SYNTHETIC SILICA GLASS OPTICAL MATERIAL HAVING HIGH RESISTANCE TO LASER INDUCED DAMAGE

摘要

Disclosed is a synthetic silica glass optical material having high resistance to optical damage by ultraviolet radiation in the ultraviolet wavelength range, particularly in the wavelength less than about 250 nm and particularly, exhibiting a low laser induced wavefront distortion; specifically a laser induced wavefront distortion, measured at 633 nm, of between about −1.0 and 1.0 nm/cm when subjected to 10 billion pulses of a laser operating at approximately 193 nm and at a fluence of approximately 70 μJ/cm². The synthetic silica glass optical material of the present invention comprises OH concentration levels of less than about 600 ppm, preferably less than 200 ppm, and H₂ concentration levels less than about 5.0×10¹⁷ molecules/cm³′ and preferably less than about 2.0×10¹⁷ molecules/cm³.