Alex Dorn, Hans Zappe and Çağlar Ataman at IMTEK, University of Freiburg, have published a plug-and-play adaptive optics microscopy approach with full-field correction in Optics Express. Ataman invented the Deformable Phase Plate and is Phaseform’s Lead Scientific Advisor; Zappe advises the company on micro-optics. It reaches a fully corrected field from the opposite direction to the group’s conjugate AO extension: rather than enlarging the region a single correction can serve, it divides the field and corrects each part in turn.
The isoplanatic patch — the area over which one wavefront correction still improves the image — is what caps the corrected field in a conventional pupil-AO microscope. This work accepts that limit and operates inside it: estimate how large the patch actually is at a given field position, correct each patch on its own, and stitch the results. The field stops being one correction problem and becomes a sequence of small ones.
This study takes a complementary approach to the conjugate AO extension published by the same group, offering a straightforward hardware integration to tackle the limited-field-of-view problem of conventional pupil-AO implementations. It introduces a modular AO attachment designed for full-field correction by segmenting the imaging field into multiple isoplanatic patches, each corrected individually before being stitched into a comprehensive corrected image.
The adaptive optics module is equipped with a 63-electrode DPP positioned close to the objective lens, achieving precise control over wavefront modulation without adding significant bulk to the optical path. A key innovation is the empirical method to estimate the isoplanatic patch size based on field position, optimizing both correction and measurement time, which is essential for samples exhibiting varying levels of aberration across the field. This system provides a user-friendly AO add-on that can significantly enhance the AO capabilities of commercial microscopy setups, making high-quality, high-resolution imaging more practical for complex samples.
The DPP is placed directly between the microscope’s objective and turret, approximating a pupil-AO configuration. This setup allows for independent correction of sub-regions across the field, effectively addressing limitations associated with field-dependent aberrations. It empirically determines the optimal isoplanatic patch size, adjusting segment sizes to enhance correction efficiency without increasing measurement time. By tiling and stitching high-quality sub-images from each patch, this approach achieves a corrected full-field image. This novel segmentation and stitching method enables the attachment to adapt to various sample types and aberrations with broad applications in biological and material imaging.
Original publication: Alex Dorn, Hans Zappe, and Çağlar Ataman, “Plug-and-play adaptive optics microscopy with full-field correction using isoplanatic patch estimation and field segmentation”, Optics Express, Vol. 32, Issue 23, 41764 (2024). DOI: 10.1364/OE.533494
