Fiber Optic Displacement and Liquid Refractive Index Sensors with Two Asymmetrical Inclined Fibers

• Main Authors: H. Z. Yang, S. W. Harun, H. Ahmad
• Format: Article
• Language: English
• Published: IFSA Publishing, S.L. 2009-09-01
• Series: Sensors & Transducers
• Subjects: Fiber-optic displacement sensor; Liquid refractive index sensor; Fiber-optic sensor
• Online Access: http://www.sensorsportal.com/HTML/DIGEST/september_09/P_493.pdf

Fiber optic displacement sensor (FODS) with two asymmetrical inclined fibers is studied theoretically and experimentally. A liquid refractive index sensor (LRIS) is then demonstrated using the similar sensor set-up. The theoretical result of the FODS is in good agreement with the experimental result, verifying the feasibility of our theoretical model. The performance of FODS is strongly depended on core radius and diameter of fibers used as well as inclination angle of two asymmetrical fiber core. The maximum sensitivities of 0.2752, 0.3759 and 0.7286 mV/μm are obtained at inclination angles of 10°, 20° and 30°, respectively. Meanwhile, the maximum linear ranges of 10.4 mm, 7 mm and 3 mm are obtained at inclination angles of 10°, 20° and 30°, respectively. The proposed LRIS produces the highest output different for increase in refractive index at displacement of 3.3 mm. At this distance, the output intensity increases almost linearly as a function of refractive index of the medium.