Backscattered Stokes vector angular pattern of individual particles in water

Individual particles' large-range angular distribution, including scattering angles near 180° of polarized light backscattering, is vital for the bio-optical model of ocean color remote sensing and Lidar. However, its simultaneous acquisition is still challenging. Backscattered Stokes vector angular pattern (BSAP) of individual particles in water is acquired by a conceptual setup with the confocal optical system, covering 112° to 179.5° scattering angles <i>θ</i>_<i>s</i> with 0.068° angular resolution and 180° maximal range of azimuthal angles <i>φ</i>_<i>s</i>. Microspheres with different sizes and materials are used to calibrate BSAP, together with Mie theory simulations. BSAPs of four kinds of microalgae are measured to characterize their physical properties in detail, on which the impacts of their size, shape, and orientation are explained by the discrete dipole approximation (DDA) simulation.