Acetic acid concentration estimation using plastic optical fiber sensor based surface plasmon resonance


Optical fiber chemical sensor based on surface plasmon resonance for sensing and measuring the refractive index and concentration for Acetic acid is designed and implemented during this work. Optical grade plastic optical fibers with a diameter of 1000 μm were used with a diameter core of 980 μm and a cladding of 20 μm, where the sensor is fabricated by a small part (10 mm) of optical fiber in the middle is embedded in a resin block and then the polishing process is done, after that it is deposited with about (40 nm) thickness of gold metal and the Acetic acid is placed on the sensing probe. It was noted from the results that the refractive index increasing as the magnitude of shifting of the dip position increase of wavelength thus concentration increasing.