Quality control of UV resistant fibers for 200-300 nm spectroscopic applications

UV solarization resistance of synthetic silica/silica fibers has been researched over many years. Fiber optic probes for applications as diverse as protein analysis, dissolution testing or high pressure liquid chromatography have been developed and successfully commercialized. Although fabrication technology for optical fibers has improved significantly and optical losses due to solarization effects have been minimized in synthetic silica fibers, the generation of UV induced defects in silica fibers due to the generation of E'centers visible in the 215 nm region is still present and can interfere with sensitive spectroscopic absorbance measurements. This work presents methodology to determine the transient response of optical fibers in the 200 nm to 300 m region during the warm up period and during measurement as a function of light power coupled into the fiber, fiber length and fiber diameter.