Quantitative phase microscopy (QPM) is pivotal for revealing phase distributions, and optical diffraction tomography (ODT) effectively showcases 3D refractive index (RI) structures across diverse technical and biological entities. Our novel polarization grating-based system, integrated with Hilbert spiral transform (HST) phase demodulation, stands out for its streamlined design, adaptability with partially coherent light, and efficient beam interference through diffraction gratings. In scenarios involving high numerical aperture (NA) paired with low magnification, standard sampling frequently falls short for proficient phase demodulation via Fourier transform. Kramers–Kronig relations enhance phase estimation but face challenges in on-axis configurations as it requires full separation of cross-correlation terms. Our solution, HST with fast iterative filtering, bypasses the need for full term separation enabling phase and amplitude estimation from holographic projections for tomographic reconstruction. Results are validated by 3D RI reconstruction of phase targets 3D printed via 2-photon polymerization and fixed neuron imaging.
|