摘要 |
<p>A thin film optical waveguide comprises a polymeric waveguiding film supported on a substrate, the film comprising a homopolymer of vinylpyridine or of a derivative of vinylpyridine in which the pyridine heterocyclic nucleus is substituted. Alternatively, a copolymer containing a major proportion of vinylpyridine, or of said derivative thereof, may be used in the film. A layer of a material having a lower refractive index may cover the film. The polymer may be modified to increase its capacity for refractive index variation in response to an electric field, by inclusion in the structure of the polymer of at least one optically non-linear moiety. The polymer may also include cross-linking. The invention also relates to laser devices wherein a laser dye is incorporated in the polymer.</p> |