A Fiber Optic Refractive Index Sensor Using a High Index Layer of TiO2.

A fiber optic refractive index sensor is fabricated here by inserting a section of no-core fiber between two multimode fibers. Thin film of titanium dioxide (TiO₂) was coated over no-core fiber to enhance the sensitivity. The sensing principle is based on modulation of evanescent wave and then intensity of transmitted light. Sensitivity of the sensor is found to increases after the coating of TiO2 layer. A high sensitivity of 67.3dBm/RIU and fast response time of 8sec is obtained by the proposed sensor. Apart from it, the fabricated sensor gives good accuracy and stable result. [ABSTRACT FROM AUTHOR]