High-Magnification Full-Color Real-Time Stereoscopic Microscopy Based on a Liquid Crystal Polarization Grating
Three-dimensional (3D) microscopic imaging is indispensable for fundamental scientific research and clinical medical diagnosis. Given that conventional widefield optical microscopy and standard confocal microscopy fail to realize high-magnification, full-color, real-time stereoscopic imaging simultaneously, we herein propose a single-optical-path 3D microscopic framework enabled by liquid crystal polarization gratings (LCPGs). The LCPG integrated at the sample plane performs polarization-dependent beam splitting to generate paired left and right viewing channels. These two disparity-bearing view channels share a unified imaging optical path compatible with commercial upright microscopes, wherein an active liquid crystal cell modulates temporal view switching for sequential camera acquisition. We further construct a white-light microscopic platform supporting integrated reflection and transmission imaging modes. Two customized LCPGs with lattice periods of 72.6 μm and 56.9 μm are fabricated, offering angular view separations of 0.84° and 1.07°, respectively. Both gratings achieve ±1st-order diffraction efficiencies above 97% with polarization crosstalk not exceeding 0.8%. The developed system acquires paired left-right images with valid binocular disparity, which can be reconstructed into intuitive stereoscopic perceptions via a 3D display monitor. This LCPG-based optical architecture upgrades standard upright microscopes to compact dual-view stereoscopic imaging systems, while fully inheriting the native merits of white-light illumination and high-magnification microscopic observation.