Light Guidıng Medium Based Optical Tilt Sensor Design

This paper presents a simple, low-cost liquid based optical tilt sensor. The sensor is designed on the basis of the variation of the amount of light passing through liquids composed of two layers placed in a container depending on the tilt angle. Light is transmitted and received by the fibers placed in the container ends. This sensor is highly sensitive to small angle values, especially depending on the fiber radius used. An average of  0.58 V/° sensitivity was obtained in the range of 0-3° by using 2.5 mm diameter fibers. This value is found to be  4.54 times  higher than the sensitivity of sensor with single liquid.

Using a Fiber Loop and Fiber Bragg Grating as a Fiber Optic Sensor to Simultaneously Measure Temperature and Displacement

This study integrated a fiber loop manufactured by using commercial fiber (SMF-28, Corning) and a fiber Bragg grating (FBG) to form a fiber optic sensor that could simultaneously measure displacement and temperature. The fiber loop was placed in a thermoelectric cooling module with FBG affixed to the module, and, consequently, the center wavelength displacement of FBG was limited by only the effects of temperature change. Displacement and temperature were determined by measuring changes in the transmission of optical power and shifts in Bragg wavelength. This study provides a simple and economical method to measure displacement and temperature simultaneously