Single-Mode Polymer Embedded Waveguide for Visible Wavelength using SU-8

We investigated the optical characteristics of a single-mode polymer waveguide in the visible wavelength region, including the blue range. We fabricated two types of polymer waveguide by using photolithography and UV-nanoimprint lithography. The polymer waveguides had an over and under cladding, and the refractive index difference between core and cladding was 0.8% at a wavelength of 633 nm. The propagation loss of the fabricated waveguide was about 0.8 to 4.4 dB/cm at wavelengths from 638 to 465 nm. The waveguide worked as a single-mode one over the whole visible region.