purpose : to compare visual outcome of aspheric and spheric intraocular lenses (iols) implantation in patients with age-related cataract in terms of visual acuity (va), contrast sensitivity (cs) and spherical aberration methods : in this prospective randomized interventional study, 59 consecutive cases of senile cataract who had been admitted for cataract surgery to farabi eye hospital, tehran,...

PURPOSE The purpose of this study was to quantify accommodation-induced changes in the spherical aberration of cynomolgus monkey lenses. METHODS Twenty-four lenses from 20 cynomolgus monkeys (Macaca fascicularis; 4.4-16.0 years of age; postmortem time 13.5 ± 13.0 hours) were mounted in a lens stretcher. Lens spherical aberration was measured in the unstretched (accommodated) and stretched (re...

The design and construction of a double-hexapole aberration corrector has made it possible to build the prototype of a spherical-aberration corrected transmission electron microscope dedicated to high-resolution imaging on the atomic scale. The corrected instrument, a Philips CM200 FEG ST, has an information limit of better than 0.13 nm, and the spherical aberration can be varied within wide li...

In modern high-numerical-aperture (NA) optical scanning instruments, such as scanning microscopes, optical data storage systems, or laser trapping technology, the beam emerging from the high-NA objective focuses deeply through an interface between two media of different refractive index. Such a refractive index mismatch introduces an important amount of spherical aberration, which increases dyn...

The aim of this study was to evaluate the accommodation response under both monoand polychromatic light while varying the amount of spherical aberration. It is thought that chromatic and spherical aberrations are directional cues for the accommodative system and could affect response time, velocity or lag. Spherical aberration is often eliminated in modern contact lenses in order to enhance ima...

It is known that the depth of focus (DOF) of the human eye can be affected by the higher order aberrations. We estimated the optimal combinations of primary and secondary Zernike spherical aberration to expand the DOF and evaluated their efficiency in real eyes using an adaptive optics system. The ratio between increased DOF and loss of visual acuity was used as the performance indicator. The r...

BACKGROUND The purpose of this study was to evaluate the correlation between contrast sensitivity and calculated higher-order aberrations based on individual natural pupil diameter after cataract surgery. METHODS This prospective study included 120 eyes from 92 patients who were randomized to receive one of four lenses, including three aspheric lenses (Acrysof SN60WF, Tecnis ZA9000, and Hoya ...

Modern transmission electron microscopes (TEM) allow utilizing the spherical aberration coefficient as an additional free parameter for optimizing resolution and contrast. By tuning the spherical aberration coefficient of the objective lens, isolated nitrogen atom columns as well as the Si–N dumbbells within the six-membered ring were imaged in b-Si3N4 along [0 0 01] and [0 0 0 1̄] projections w...

Split laser beams of varying separation were directed through the crystalline lenses of rats of young, old, and intermediate age. The variation in back vertex distance was determined from photographs of the focal effects of each lens. The results indicate that negative spherical aberration of the rat lens increases with age. In addition, local reversals in the slopes of the negative spherical a...