INTERNATIONAL CONFERENCE ON MATHEMATICS – ENGINEERING – NATURAL & MEDICAL SCIENCES , Al Karak, Ürdün, 30 - 31 Ocak 2021, ss.502-503
In
this study, U-shaped bending fiber optic sensor tips based on bending losses
and sensitivity to the medium’s refractive index changes were designed and
produced. U-1, U-2, and U-3 sensing tips were produced by using bare polymer
fibers with three different fiber diameters of 1, 2, and 3 mm, respectively.
Since all the fibers have a high numerical aperture value of 0.5, this
situation facilitates the light’s guiding into the fiber easily. Tips’
responses during the transition between air and water were considered and
obtained sensitivity degrees. Three sensor tips were used to measure
ethanol-water and methanol-water mixtures. The tip named U-2 was found to be
most suitable for the detection of ethanol concentration. This sensor tip was
able to detect the change in the refractive index of Δn<5×10-4
RIU with the linearity of 0,999 in ethanol concentrations. Similarly, the sensor tip named U-3 was the most appropriate tip for the
detection of methanol concentration. This sensor tip was able to detect the
difference in the refractive index of Δn<2×10-4 RIU with the
linearity of 0,997. Both sensor tips were able to
detect with high precision, stability, and repeatability up to 15% alcohol concentration
in the mixtures. Besides, the sensors produced very simple, easy, and cheap can
be benefited to recognize alcohol type in water.