Slightly off-axis holography with partially coherent illumination implemented into a standard microscope

We have recently reported on a simple, low cost and highly stable way to convert a standard microscope into a holographic one [Opt. Express 22, 14929 (2014)]. The method, named as Spatially-Multiplexed Interferometric Microscopy (SMIM), proposes an off-axis holographic architecture implemented onto a regular (non-holographic) microscope with minimum modifications: the use of coherent illumination and a properly placed and selected onedimensional diffraction grating. In this contribution, we report on the implementation of partially (temporally reduced) coherent illumination in SMIM as a way to improve quantitative phase imaging. The use of low coherence sources forces the application of phase shifting algorithm instead of off-axis holographic recording to recover the sample's phase information but improves phase reconstruction due to coherence noise reduction. In addition, a less restrictive field of view limitation (1/2) is implemented in comparison with our previously reported scheme (1/3). The proposed modification is experimentally validated in a regular Olympus BX-60 upright microscope considering calibration samples (resolution test and microbeads) and for two different microscope objectives (10X and 20X).