Optical fiber sensor based on redistribution of power among several guided modes

Abstract

Optical fiber sensors are suitable for measuring almost all magnitudes these days. This article describes one new possible area of optical fiber sensors. These sensors use for their function fundamentals of redistribution of power inside optical fiber. This principle should allow constructing a very sensitive optical fiber sensor. We designed novel optical fiber that affords utilizing of optical fiber for telecommunications and measurement at the same time. This fiber is designed to work on two wavelengths. This fiber works on telecommunication wavelength of 1550 nm in single mode regime and works on measurement wavelength of 850 nm in quasi-single mode regime. The refractive index profiles of real fabricated optical fiber samples and their development are shown in this article as well. All fiber samples were made thanks to grant cooperation with Academy of Science of the Czech Republic. The aim of this article is that brings new approach to utilization of optical fiber as a sensor based on redistribution of optical power among several guided modes and to show novel optical fiber structure design that agrees with conditions for such operations.