Development of heat resistant UV transmission optical fibers

摘要

When optical fibers are exposed to ultraviolet radiation (UV), transmission loss occurs in the Deep Ultraviolet radiation (DUV) region. In recent years, available wavelengths in the ultraviolet has expanded to the DUV region but the above transmission loss has become a problem. We have developed a heat-resistant optical fiber with enhanced UV resistance in the DUV region and evaluated its UV resistant characteristics after heavy hydrogen lamp and ArF excimer laser exposure. During 1,000 hours of exposure under heavy hydrogen lamp (0.21mW/cm{sup}2 @250nm), the variation rate of the transmitted quantity of light was maintained at 70% (when initial value was 100%), indicating much improvement. Under ArF excimer laser exposure (12mJ/cm{sup}2/pulse), the variation rate of the transmitted quantity of light was approximately 54% at 1.2×10{sup}7 pulses.