A Shipborne Photon-Counting Lidar for Depth-Resolved Ocean Observation

Depth-resolved information is essential for ocean research. For this study, we developed a shipborne photon-counting lidar depth-resolved oceanic plankton observation. A pulsed fiber laser with frequency doubling to 532 nm acts as light source, generating single pulse at the micro-joule level width of less than 1 ns. The receiver capable simultaneously detecting elastic signal two orthogonal polarization states, Raman scattering from seawater, and fluorescence chlorophyll A. data acquisition system utilizes technique record each photon event, after which backscattering intensity can be recovered by counting photons multiple pulses. Benefitting immunity statistical detection method ringing effect detector amplifier circuit, high-sensitivity high-linearity backscatter measurements are realized. In paper, analyze correct after-pulse phenomenon signals through experiments theoretical simulations. Through correction, attenuation coefficient retrieved corrected in good agreement diffuse coefficients calculated situ instrument, indicating potential observation applications.