Comprehensive and Analytical Review on Optical Fiber Refractive Index Sensor

Refractive index (RI) of substance, the liquid is an imperative optical measure since it possesses the optical property of substance and liquid. The simple and precise measurement method of the refractive index of transparent liquids plays a crucial role while designing optical instruments also vital in chemical work. It is used in various applications like environmental pollution monitoring, mammalian tissue examination, polymers, and for identifying the concentration of organic substances. Though a lot of people researched optical fiber-based refractive index sensor. But then also the design of the efficient and sensitive sensor is still the most challenging field in optical technology. A comprehensive review has been done and tried to make a comparative study of various existing devices and systems in this field. The challenges and some issues are detected while fabricating and designing respective sensors to be addressed are discussed in this paper as well. The primary purpose of this review paper is to focus on various methodologies and fabrication processes used in designing the sensor.