Fig. 1: Visualization for the experimental images with different material samples in.
From: Smart polarization and spectroscopic holography for real-time microplastics identification
(a) 0∘, (b) 45∘, (c) 90∘, and (d) 135∘. The scale bar is 0.5 mm. Colorbar is the value of the intensity. The material samples of polyethylene terephthalate, polypropylene, polycarbonate, and polyvinyl chloride perform various in the different polarization directions when passed through by the same incident light. (e) System schematic of SPLASH. Unpolarized light emitted by a laser diode with 532 nm wavelength. A convex lens is used for beam collimation. A linear polarizer is combined with a quarter-wave plate and inserted in the light path to adjust the laser intensity without introducing phase modulation. Then, the laser light goes through the sample plate, arriving at the sensing plane, and is analyzed by a polarization camera. A full Stokes polarization mask is mounted in front of the camera imaging sensing plane to record the sample images with four Stokes states (S0, S1, S2 and S3) in one shot.
