High-density wiring of polymer optical waveguides fabricated using a microdispenser

Single-mode polymer optical waveguides with circular cores are successfully fabricated using the Mosquito method. Furthermore, fabrication conditions for densely aligned waveguides having graded-index circular cores with a 25-μm diameter are also investigated, in which the inter-channel pitch is reduced to 60 μm. By applying the three-dimensional (3-D) alignment conditions with the Mosquito method, fan-out waveguides are fabricated: three cores are obliquely aligned with a 40-μm pitch, while at the other end, the three cores are horizontally aligned in line with a 250-μm pitch. The insertion loss as low as 2.85 dB at 850-nm wavelength is observed for a 10-cm long fan-out waveguide.