Refractometric fiber-optical detectors of liquids: effect of residual liquid film

Abstract

We analyze the response of the optical refractometric detection element of a hemispherical shape in the presence of a contamination in the form of a him of liquid on its surface. We show that the liquid film distorts the detector's response to the refractive index of the surrounding medium. This distortion is more pronounced in the case of small-size detection elements, such as those employed in the fiber-optical refractometric sensors.