Optical fiber for deep ultraviolet light

Deep ultraviolet optical fibers are fabricated using modified SiO2 glasses containing 2000-ppm fluorine for the clad and 200 ppm for the core. The tra nsmission at 193 mn is improved to more than 60%/m by optimizing the fiber drawing condition. The H-2-impregnation into the fiber suppresses the degra dation of the transmission by irradiation of ArF excimer laser (50 mJ/cm(2) /pulse). Further improvement may be expected by reducing oxygen-deficient c enter (I) defect generation in the drawing process.