The proposed program would develop a low cost optical sensor for detection of oil and oil-derived substances suspended underwater. The sensor will be based on commerical-off-the-shelf components and developed to interface with existing ocean drifters or previously deployed sensor networks. The sensor will use a highly lipophilic material to locally enhance the concentration of hydrocarbons and improve the optical absorbance for detection.
The proposed sensor will combine inexpensive proven absorption technologies to detect oil in water. The main limitation of absorption based detection has always been the minimum detectable concentration. Since absorption is a function of path length, the typical solution is to extend the optical path so more of the absorbing material can interact with the light. Another approach is to virtually increase the path length through use of a cavity structure. The proposed sensor uses a lipophilic material to act as a amplifying medium in a cavity.
Unfortunately the material is opaque so instead of using a standard transmission based measurement, an optical scattering approach is used where both the transmission and acute angle reflective scattering is used to determine the concentration of hydrocarbons present.The overarching goal of the sensor development is to provide a valuable tool to scientists and engineers to collect essential data in real time. That data can then be used to improve predictive models and enhance understanding of underlying processes of physical distribution, dispersion and dilution of oil and oil-derived substances.