Oil Thickness Measurement Using Laser Refraction

Abstract

The problem of oil spills from ships is a serious cause of marine pollution. Therefore, estimating the thickness of oil is necessary to determine the overall runoff. Usually, measures can be taken against the spread of oil for the measurement of the thickness of the oil strip. Further, Snell's law can be used to quantify the rays refracted in oil. This study proposed a quantitative study of oil thickness based on the above mentioned approach. In particular, the test is performed by passing a laser beam through an air/oil/water layer. When a laser beam travels from one medium to another, it is refracted by an amount proportional to the difference in refractive indices of the mediums. Subsequently, Snell's law is used to calculate the position of the refracted laser beam, and the position is recorded by a camera module remotely controlled by a microcontroller. The captured image of the beam position is image processed to obtain the X and Y coordinates of the beam ray position using Python OpenCV. After measuring the X and Y coordinates, the oil thickness is calculated. However, the experimental results indicate that the error in the estimation of oil thickness by the proposed method is around 0.1%.