Snapshot Polarization-Sensitive Holography for Detecting Microplastics in Turbid Water
Jianqing Huang, Yanmin Zhu, Yuxing Li, Edmund Y. Lam
Abstract
Microplastic (MP) pollution is a serious environmental problem, which can severely harm the earth’s ecosystems and human health. However, in situ characterization of MP particles remains challenging due to the complex natural environments such as turbid water. In this work, a hybrid computational imaging approach based on holography and polarimetry is developed for rapid and accurate assessment of MP pollution in turbid water. In particular, the influence of scattering media on MP detection is experimentally studied. With a compact optical configuration and an efficient computational method, this imaging system is capable of seeing through scattering media and obtaining multimodal information about the object in a snapshot. The results suggest that polarization features can substantially improve image contrast even in highly turbid water. In addition, it is demonstrated that the polarization properties of objects are new discriminative features for identifying MP materials. Therefore, such a portable system is extremely useful for the further development of MP monitoring in natural environments.