PHOTOCHEMICAL LASER WRITING OF POLYMERIC OPTICAL WAVE-GUIDES

We report a rapid one-step laser writing process for forming optical channel waveguides by photochemically lowering the index of refraction in selected areas of thin, highly photosensitive polymeric films. We have demonstrated the concept by forming single- and multimode waveguides in films composed of poly(methylmethacrylate) containing (4-N-N-dimethylaminophenyl)-N-phenyl nitrone. The effects of ultraviolet fluence on the refractive index of the films and on channel lightwave confinement were examined. Low loss (1.5 dB/cm) channels were produced with ultraviolet fluences as low as 20 mJ/cm2.