Phaseform’s mission is to make high-resolution microscopy accessible to all, redefining adaptive optics (AO) in microscopy with solutions that are both user-friendly and versatile. Two recent publications from our collaborators at IMTEK, University of Freiburg, highlight breakthroughs in overcoming a key limitation of traditional AO systems: the restricted field of view due to the isoplanatic patch size.
In standard AO systems, the isoplanatic patch—a region where aberration correction is effective—is typically small, limiting AO’s ability to handle larger, diverse imaging areas. This is especially challenging in fields like biological imaging, where samples are extensive and varied.
The following recent publications introduce two innovative solutions using Phaseform’s Deformable Phase Plate (DPP) technology, greatly expanding AO’s effectiveness in standard commercial microscopes.
“Conjugate adaptive optics extension for commercial microscopes”, (Advanced Photonics Nexus, Vol. 3, Issue 5, 2024), introduces a conjugate adaptive optics extension that integrates seamlessly into standard microscopes. This module places our DPP in the conjugate position relative to the source of optical distortions, effectively correcting for spatially varying aberrations across a large field of view.
“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, introduces a modular plug-and-play AO system for microscopy, addressing the limited field of view by dividing the imaging field into isoplanatic patches, each corrected independently with the DPP. The setup allows for seamless, full-field high-resolution imaging, even in samples with complex aberrations.
This work presents a conjugate AO system that can be retrofitted onto commercial microscopes, marking a shift from research-specific AO systems to more accessible, plug-and-play solutions. This extension leverages a Deformable Phase Plate (DPP), the refractive wavefront modulator from Phaseform, to correct complex, field-dependent aberrations over large areas, even with substantial sample-induced distortions. A unique feature is its in-line design, allowing precise axial adjustments of the DPP, thereby optimizing image correction across diverse imaging depths. This system also enables sensorless aberration correction using indirect wavefront sensing, eliminating the need for complex folding optics traditionally required for AO, thus reducing system bulk and making it applicable to a range of biological and biomedical applications.
This paper presents the first conjugate AO extension compatible with commercial microscopes, which can be retrofitted between the camera port and image sensor. This setup introduces a deformable phase plate (DPP) as the corrective element, allowing for in-line architecture without complex additional optics. Unlike traditional systems that rely on deformable mirrors positioned at the pupil plane, this setup optimizes AO for complex, field-dependent aberrations across a larger field of view. The DPP’s position can be adjusted axially, allowing the system to optimize the corrective plane.
This extension’s design offers a plug-and-play solution that simplifies integrating AO into existing microscopes, thus broadening accessibility for various biomedical imaging applications.
The study demonstrates that this system significantly extends the correctable field of view beyond what is achievable with conventional pupil-plane AO systems. By optimizing the conjugate plane position, the extension achieves nearly full-field correction, enhancing imaging quality and detail across larger sample areas, even in the presence of strong aberrations.
This study takes a complementary approach compared to the previous paper, offering a straightforward hardware integration to tackle the limited field of view issue 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.