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bioRxiv · 10.64898/2026.04.28.721333

Universal approach to wave-optical calculations of point spread functions in microscopy (and beyond)

Gligonov, I.·Loetgering, L.·Tenopala-Carmona, F.·Hsieh, C.-L.·Gregor, I.·Enderlein, J.
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Abstract

Optical microscopy is fundamental to modern life-science research, yet interpreting its results requires precise modelling of point spread functions (PSFs) within complex environments. This manuscript introduces a versatile and efficient approach to wave-optical PSF calculations that extends existing frameworks by incorporating detection PSF modelling through the principle of reciprocity. Accompanying this work is a free MATLAB software package centred on a single, minimalistic core function, PlaneWaveExc.m, which utilizes a plane-wave superposition based on the Richards-Wolf model. Despite its simplicity, the framework accounts for "real-life" complexities such as systemic aberrations, arbitrary amplitude and phase modulations, and stratified media with complex-valued refractive indices. We demonstrate the softwares broad applicability through diverse case studies, including single-molecule imaging, STED microscopy, the segmented aperture of the James Webb Space Telescope, and coherent wide-field iSCAT microscopy. Each example is supported by dedicated scripts to facilitate adaptation for specific research needs.

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Gligonov, I., Loetgering, L., Tenopala-Carmona, F., Hsieh, C.-L., Gregor, I., Enderlein, J.. 2026-04-30. Universal approach to wave-optical calculations of point spread functions in microscopy (and beyond). https://doi.org/10.64898/2026.04.28.721333

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