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bioRxiv · 10.64898/2026.03.18.711080

Open Fourier Ptychographic Microscopy (OpenFPM)

Walker, L. D.·Copeland, L.·Rooney, L. M.·Bendkowski, C.·Shaw, M. J.·McConnell, G.
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Abstract

Fourier ptychographic microscopy (FPM) uses sequential multi-angle illumination and iterative phase retrieval to recover a high-resolution complex image from a series of low-resolution brightfield and darkfield images. We present OpenFPM, an open-source FPM platform in which conventional and optomechanical hardware is replaced with compact, low-cost 3D printed components. Illumination, sample and objective positioning, and camera triggering are controlled using a Python-based interface on a Raspberry Pi microcomputer. With a 10 x /0.25 NA objective lens and 636 nm illumination, OpenFPM experimentally achieves amplitude and phase reconstructions with an effective synthetic NA of 0.90 over a 1 mm field-of-view. This platform gives researchers accessible and affordable hardware for developing and testing LED-array microscopy techniques for a range of biomedical imaging applications.

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Walker, L. D., Copeland, L., Rooney, L. M., Bendkowski, C., Shaw, M. J., McConnell, G.. 2026-03-20. Open Fourier Ptychographic Microscopy (OpenFPM). https://doi.org/10.64898/2026.03.18.711080

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