Locally pressed etched optical fiber with PDMS coating for a sensor application

In this work, the fabrication and experimental investigation of multimode optical fiber with a cladding material replacement is presented. A short piece of fiber’s cladding is etched away and substituted by a polydimethylsiloxane (PDMS) material. This elastomer is characterized by a unique feature of refractive index changes with the increasing particle density. The device principle is based on total internal reflection. If the PDMS is pressed, there is a change of elastomer refractive index and modes confined within the fiber core are partially or totally irradiated. This demonstration paves the way for further development of fiber optic sensors, particularly attractive for weight, load, extension, and pressure parameters monitoring applications.