Sensitive Interferometric Force Sensor Based On Multicore Optical Fibre

A simple, interferometric force sensor based on a multicore optical fiber (MCF) that operates in reflection mode is presented. The device consists of a short segment of MCF inserted at the distal end of a conventional single mode optical fiber (SMF). To demonstrate the concept we used a mechanical piece with grooves to press the MCF. In this way the external force on the MCF is converted in localized pressure on the fiber which causes attenuation losses to the interfering modes and makes the interference pattern to shrink. The changes experienced by the interference pattern can be easily monitored. The sensor here proposed is highly sensitive since it can resolve forces down to 0.01 N