Transmitted intensity variations in a plastic-clad silica optical fiber by exposing to gasoline octane numbers 87 and 92 at different temperatures

We show in this paper the performance of transmitted light through a plastic clad (polymer) optical fiber, caused by optic fiber contact with commercial gasoline at different temperature influences. Our experimental setup is based in the methodology of the evanescent field absorption and the changes of the refractive index. The selected spectrum range studied is from 1100 to 1800 nanometers (nm) with temperature variation range from 5 to 50 °C. We found the intensity transmitted increases in the 1500 to 1550 nm when the optical fiber is exposed to gasoline octane numbers 87 and 92, respectively. It is also found too that in 1200 nm the transmittance variation on the fiber due to temperature changes is negligible, compared with the hydrocarbon influence. This result let us know that 1200 nm wavelength can be used for a leak hydrocarbon sensor.