Advanced fiber-optical refractometry by reflection displacement sensors

Abstract

Advanced fiber-optical displacement sensors and refractometers have been developed. Three-fiber displacement sensor has been investigated as a refractometer by computer simulations, and important regularities have been revealed. A reflection fiber-optical displacement sensor of new configuration, consisting of two pairs of the fibers with the definite angle between the measuring tips of fibers in the pairs, to indicate and measure refraction index of gas and liquid water solutions have been proposed, designed and experimentally investigated. This refractometer configuration drastically improves measuring sensitivity in comparison with the recently diveloped parallel three-fiber measuring method. Refractometer sensitivity Snsub=4X10(-7)RIU/mV.