Highly Reliable Flexible Active Optical Links

We present a process to embed commercially available optical material layers into a flexible foil. Patterning of the embedded layers results in highly transparent low loss flexible waveguides. Bending of the foil down to a bending radius of 5 mm causes no additional optical propagation losses. Vertical-cavity surface-emitting laser diodes (VCSELs) and photodiodes are thinned down to 20 ¿m and embedded inside the cladding layer of the waveguides. They are optically coupled with the use of embedded micro-mirrors. The result is a thin foil of 150- ¿m thickness with embedded active optical low-loss links. Accelerated aging tests prove the reliability of the embedded optical links exposed to humidity and temperature cycling.