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The next generation of optical data storage system beyond DVDs will use blue laser light and an objective lens with a high numerical aperture of 0.85 to increase storage capacity. Such high numerical aperture systems have an inherent higher sensitivity to aberrations. In particular, the spherical aberration caused by cover layer thickness tolerances and--more obvious--by dual-layer disks with a typical separation of approximately 20 microm between the two layers must be compensated. We propose a novel transmissive nematic liquid-crystal device, which is capable of compensating spherical aberration that occurs during the operation of optical pickup systems.
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http://dx.doi.org/10.1364/ao.43.002722 | DOI Listing |
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.
Br J Ophthalmol
September 2025
Ministry of Health Istanbul Beyoglu Eye Training and Research Hospital, Istanbul, İstanbul, Turkey.
Purpose: To evaluate postoperative changes in corneal topographic parameters and higher-order aberrations (HOAs) following Müller muscle-conjunctival resection (MMCR) in patients with mild-to-moderate ptosis.
Methods: This prospective clinical study included patients who underwent MMCR after a positive phenylephrine test and with good levator function who were evaluated. Preoperative and postoperative best-corrected visual acuity (BCVA), margin reflex distance 1 and corneal parameters (flat meridian, steep meridian, simulated keratometry, maximum keratometry), along with HOAs including coma, trefoil, spherical aberration, secondary astigmatism and quadrifoil, were assessed at week 1, month 1 and month 3.
Biol Reprod
September 2025
Département des sciences animales, Faculté des sciences de l'agriculture et de l'alimentation, Université Laval, Québec, Qc, Canada.
Deep 3D imaging of oocytes shows several difficulties. Their large size, spherical shape causes depth-dependent artefactual shadow in the middle, resulting from refractive index mismatches induced by turbid organelles and lipid droplets. These mismatches lead to optical aberrations, increasing the laser spot size at the confocal pinhole plan and causing significant attenuation of fluorescence intensity making difficult to clearly image fine structures such as the transzonal projections (TZPs) connecting cumulus cells and the oocyte.
View Article and Find Full Text PDFJpn J Ophthalmol
September 2025
Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Purpose: To investigate and analyze gender-related differences in myopia prevalence and factors associated with myopia progression in school-aged children.
Study Design: Observational study.
Methods: This study involved 2,298 eyes (boys = 1194 eyes; girls=1104 eyes) of 1149 school children (597 boys; 552 girls) in two elementary/junior high schools in Kyoto Japan, examined from 2013 through 2022.
Eur J Ophthalmol
September 2025
Department of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Hospital São Paulo, Universidade Federal de São Paulo, Sao Paulo, SP, Brazil.
PurposeThis study evaluated the safety and effectiveness of two models of intrastromal corneal ring segments (ICRS)-symmetric (uniform thickness and base width) and asymmetric (progressive thickness and base width)-for the treatment of oval phenotype keratoconus.MethodsA prospective, randomized, controlled clinical study was conducted on 64 eyes from 47 patients, divided into two groups: Group 1 (33 eyes) received symmetric ICRS, and Group 2 (31 eyes) received asymmetric ICRS. Comprehensive ophthalmic evaluations, including visual acuity, corneal topography, tomography, and aberrometry, were performed preoperatively and at 1, 3, 6, and 12 months postoperatively.
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