Enhancing photosensitivity in near UV/vis band by doping 9-vinylanthracene in polymer optical fiber

We report that the photosensitivity at near UV/vis band of PMMA-based polymer optical fiber (POF) can be enhanced by introducing 9-vinylanthracene (9-VA) into the fiber core, based on its photo-crosslinking mechanism. The enhanced photosensitivity was demonstrated by the UV–vis absorption and photoluminescence spectra. An index change of 8×10−4 (at 1550 nm) in a POF doped with 0.2 mol% 9-VA was achieved under very low intensity (3.1 mW/cm2) and 10 min exposure of UV lamp (365 nm dominant). As an exemplary use, long period gratings (LPGs) were fabricated with a point-to-point technique in the photosensitive POF – the first time to our knowledge.