• • Millisecond-scale polarization switching via integrated LC modulator enables dynamic mode selection between depth-sensitive double-helix PSF (LCP) and extended DOF imaging (RCP), directly addressing the resolution–DOF trade-off that limits conventional fixed-focus systems in real-time 3D microscopy.
• • Depth extraction accuracy validated with axial displacements of Δz1 = 30.5 μm, Δz2 = 0 μm, and Δz3 = −48.3 μm mapped to rotation angles β = −25.6°, 0°, and 16.9°, respectively, providing a calibration curve for quantitative depth sensing without mechanical scanning.
• • Near-diffraction-limited lateral and axial resolutions achieved at 635 nm using a-Si:H meta-atoms optimized via RCWA, with high transmittance and precise propagation/geometric phase control, ensuring imaging fidelity comparable to bulky objective-based systems.
• • Depth-resolved imaging demonstrated on biological specimens (rubber-tree leaf, skeletal-muscle cross-section, live planarian) with color-coded depth retrieval, confirming operational viability for clinical histology and in vivo applications where tissue scattering and dynamic motion demand rapid, compact instrumentation.