LiNbO_3 platforms for optical fiber alignment

A technique for incorporating a groove into a ${\mathrm{LiNbO}}_3$ substrate is described. Both V grooves for fiber alignment and vertical grooves for waveguide end-face formation can be fabricated with this technique. The proposed fabrication method is based on an excimer-laser ablation and a high-speed rotation saw cut for ${\mathrm{LiNbO}}_3$. The former process provides a variety of cross-sectional groove shapes by changing the ablation mask shape of ${\mathrm{LiNbO}}_3$, and the latter provides an optical-quality cutting face. The proposed fabrication method is simple and provides low-cost optical platforms not only for ${\mathrm{LiNbO}}_3$ but also for glasses, polymers, and semiconductors.