Design and performance of active coupler for plastic optical fibres

A simple and successful design of a new active coupler for plastic optical fibres (POF) is presented. It consists of a 2/spl times/2 coupler with a polymer-dispersed liquid crystal (PDLC) film sandwiched in it, which takes advantage of the electrooptic effect of the PDLC. More than 3 dB of variation can be achieved by applying electric fields below 1.5 V//spl mu/m.