Fig. 1.

Optical setup and working principle of GLIM. a GLIM optical setup. The GLIM module is designed as an add-on module connected to the output port of an inverted microscope. This module shifts the phase of one polarization component using an SLM while keeping the other unmodified. Interference patterns generated by these two components are recorded and transferred to a computer for phase-gradient extraction. b Four frames are acquired by the GLIM module, one for each phase shift applied by the SLM. Using these images, we obtain the phase-gradient map and integrate it along the direction of the shift to recover the quantitative phase map. c Extracted quantitative-gradient map of two 3 µm polystyrene beads immersed in oil. d Integrated phase map of a 4.5 µm polystyrene microbeads at NA_con = 0.09. e Cross-sections of the reconstructed phase and the computed ground truth (black dashed curve) taking into account blurring due to diffraction (Eq. (3))