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arXiv · 2101.07870

Spatial coherence control and analysis via micromirror-based mixed-state ptychography

Ruslan Röhrich·Femius Koenderink·Stefan Witte·Lars Loetgering
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Abstract

Flexible and fast control of the phase and amplitude of coherent light, enabled by digital micromirror devices (DMDs) and spatial light modulators (SLMs), has been a driving force for recent advances in optical tweezers, nonlinear microscopy, and wavefront shaping. In contrast, engineering spatially partially coherent light remains widely elusive due to the lack of tools enabling a joint analysis and control sequence. Here, we report an approach to coherence engineering that combines a quasi-monochromatic, thermal source and a DMD together with a ptychographic scanning microscope. The reported method opens up new routes to low-cost coherence control, with applications in micromanipulation, nanophotonics, and quantitative phase contrast imaging.

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Ruslan Röhrich, Femius Koenderink, Stefan Witte, Lars Loetgering. 2021-01-19. Spatial coherence control and analysis via micromirror-based mixed-state ptychography. https://doi.org/10.1088/1367-2630%2Fabf389

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