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The single sideband (SSB) framework of analytical electron ptychography can account for the presence of residual geometrical aberrations induced by the probe-forming lens. However, the accuracy of this aberration correction method is highly sensitive to the invested electron dose, in part due to the necessity of phase unwrapping. In this work, we thus propose two strategies to improve the performance in low-dose conditions: confining phase unwrapping within the sidebands and selecting only well-unwrapped sidebands for calculating aberration coefficients. These strategies are validated through SSB reconstructions of both simulated and experimental 4D-STEM datasets of monolayer tungsten diselenide (WSe). A comparison of results demonstrates significant improvements in Poisson noise tolerance, making aberration correction more robust and reliable for low-dose imaging.
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http://dx.doi.org/10.1016/j.ultramic.2025.114225 | DOI Listing |
Light Sci Appl
September 2025
Laboratory of Quantum Information, University of Science and Technology of China, 230026, Hefei, China.
Quantum imaging with spatially entangled photons offers advantages such as enhanced spatial resolution, robustness against noise, and counterintuitive phenomena, while a biphoton spatial aberration generally degrades its performance. Biphoton aberration correction has been achieved by using classical beams to detect the aberration source or scanning the correction phase on biphotons if the source is unreachable. Here, a new method named position-correlated biphoton Shack-Hartmann wavefront sensing is introduced, where the phase pattern added on photon pairs with a strong position correlation is reconstructed from their position centroid distribution at the back focal plane of a microlens array.
View Article and Find Full Text PDFIEEE Trans Med Imaging
September 2025
In ultrasound imaging, propagation of an acoustic wavefront through heterogeneous media causes phase aberrations that degrade the coherence of the reflected wavefront, leading to reduced image resolution and contrast. Adaptive imaging techniques attempt to correct this phase aberration and restore coherence, leading to improved focusing of the image. We propose an autofocusing paradigm for aberration correction in ultrasound imaging by fitting an acoustic velocity field to pressure measurements, via optimization of the common midpoint phase error (CMPE), using a straight-ray wave propagation model for beamforming in diffusely scattering media.
View Article and Find Full Text PDFJ Refract Surg
September 2025
Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China.
Purpose: To evaluate axis-dependent visual and refractive outcomes of small incision lenticule extraction (SMILE) in patients with interocular astigmatic axis discordance.
Methods: Seventy-five patients (150 eyes) with interocular astigmatic axis discordance were included in the study. Based on interocular axis combinations, patients were stratified into three cohorts: with-the-rule (WTR)/against-the-rule (ATR) (n = 19), WTR/oblique astigmatism (OA) (n = 39), and ATR/OA (n = 17).
J Refract Surg
September 2025
Department of Refractive Surgery, Aier Eye Hospital, Jinan University, Guangzhou, Guangdong, China.
Purpose: To report the refractive outcome of femtosecond laser-assisted lenticule intrastromal keratoplasty (LIKE) in correcting moderate to high hyperopia. Intraoperative effective optical zone (EOZ), centration offset, and postoperative higher order aberrations (HOAs) were analyzed to better understand factors affecting postoperative outcomes.
Methods: This was a prospective, consecutive case series study of LIKE for correcting hyperopia in one department from 2018 to 2023.
Purpose: To evaluate visual and refractive outcomes, visual quality, patient satisfaction, and spectacle independence 3 months after phacoemulsification with bilateral non-diffractive enhanced depth of focus (EDOF) lens implantation.
Methods: This study included 68 eyes of 34 consecutive patients, with 51.5% undergoing refractive lens exchange and 48.