Polymeric resin-filled optical couplers with mode mixing and polarization scrambling microparticles

It was found that the performance of polymeric multimode combiners and splitters could be enhanced by the addition of mode mixing microspheres. The microparticles were silica, which had a slightly different index of refraction (1.46) than that (1.40) of the silicone polymeric material in which they were suspended. This index difference causes both refractive and diffractive mode mixing effects. The refraction and diffraction causes light to be scattered preferentially into higher-order modes. When propagating light reaches equilibrium and uniformity in the propagating modes, it is known that in large, high-NA , step index waveguides the power distribution across the aperture of the waveguide is also uniform. This means that the couplers can achieve the fiber-to-fiber uniformity required to make both combiners and splitters. Loss and near-field uniformity measurements of large polymer waveguides excited by a relatively small collimated HeNe laser have been carried out. Uniformity measurements of complete 1×7 splitters containing a visible diode laser are also presented. The application of this technology to a polymeric photon switch is discussed