Abstract

Femtosecond laser microfabrication holds some unique advantages compared to other technologies which are limited to in-plane processing or masks. If the modification in transparent materials manifests itself as an increase in refractive index, it enables the fabrication of three-dimensional waveguides along virtually arbitrary paths. This direct waveguide writing is already widely applied on glasses and crystals [1]. Despite some promising results [2], the transfer of this technology to polymer materials remains a task with still several challenges to overcome [3]. For instance, longterm stability is a widely observed problem. Time dependence of the refractive index change leads to a decay of the waveguide.

© 2015 IEEE