Flexible thin-film polymer waveguides fabricated in an industrial roll-to-roll process

The fabrication of flexible low-loss, thin-film, foil-based polymer waveguides with grating couplers employing a high-volume industrial roll-to-roll process is demonstrated. The embossed waveguides feature propagation losses of less than 1  dB/cm (633 nm, TE polarization), bending losses of 0.4–0.8  dB/360° for bending radii as small as 2 mm, and grating coupling efficiencies of up to 25%. In addition, the waveguides possess a thermo-optic coefficient of −1.58×10−4  1/°C. The fabricated waveguides are promising candidates for short-distance data communication as well as for sensing applications.