A method for butt-coupling optical fibres to liquid crystal planar waveguides

In most optical applications of liquid crystals, namely liquid crystal displays and free-space optics, light propagates mainly perpendicular to the substrates; in these cases the sealing of the device is not critical for the optical performance. As liquid crystals are gaining interest in integrated optics applications (where the propagation is in the plane of the wafer), we also have to deal with at least two additional facets for the light input and output. In this communication, we expose a simple and practical method to achieve effective interface that shows good compatibility with nematic liquid crystals.