Laser Sensor Development for Fluorescence Detection of Plastics and other Anthropogenic Compounds Dissolved in Seawater

The long-term goal is to build and deploy a highly sensitive, in situ AUV-mounted instrument designed to locate and identify plastic and rubber-coated objects, such as mines, in the water column and buried within the seafloor. It is anticipated that a compact, single laser LIF system with optical filtered PMT detectors will provide real time detection of plastic and carbon compounds. Projected limits of sensitivity in situ are in the range of parts per trillion (pptr) for this sensor, an improvement of orders of magnitude over existing fluorescence sensors. Oceanographic applications include UV-vis spectral characterization of dissolved and particulate (phytoplankton) fluorescence for remote sensing, plume tracking, and pollution applications. The multi-channel UV laser-induced fluorescence sensor (MUVLIFS) will ultimately be integrated and deployed on an autonomous underwater vehicle (AUV) to enhance strategic and oceanographic applications.