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1.
J Opt Soc Am A Opt Image Sci Vis ; 36(4): B132-B137, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31044993

RESUMEN

This paper proposes a customized and versatile optical setup to evaluate the optical performance of different commercially available intraocular lenses (IOLs). The setup was used to measure the wavefront error induced by different IOL models, verifying and analyzing the magnitude of low- and high-order aberrations induced by currently available IOLs. Independent analyses included non-toric spherical and aspheric IOLs from three different manufacturers. Three different dioptric powers were tested: 15, 20, and 25 D from each model. Dioptric power, induced cylinder, and spherical aberration were measured in each tested lens. All lenses had dioptric power within the tolerated margin of error. Induced cylinder was also within the current standards and clinically irrelevant. Spherical aberration varied according to the analyzed dioptric power and to the IOL model. We reported on the importance of the plane where the spherical aberration is reported, IOL or cornea. All analyzed IOLs were within current standards for the dioptric power and induced cylinder. Spherical IOLs had higher spherical aberration measured at the IOL plane.


Asunto(s)
Lentes Intraoculares , Dispositivos Ópticos , Diseño de Equipo , Humanos , Control de Calidad
2.
Sensors (Basel) ; 18(10)2018 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-30274297

RESUMEN

This work presents a numerical simulation of a Hartmann-Shack wavefront sensor (WFS) that assesses the impact of integrated electronic circuitry on the sensor performance, by evaluating a full detection chain encompassing wavefront sampling, photodetection, electronic circuitry and wavefront reconstruction. This platform links dedicated C algorithms for WFS to a SPICE circuit simulator for integrated electronics. The complete codes can be easily replaced in order to represent different detection or reconstruction methods, while the circuit simulator employs reliable models of either off-the-shelf circuit components or custom integrated circuit modules. The most relevant role of this platform is to enable the evaluation of the applicability and constraints of the focal plane of a given wavefront sensor prior to the actual fabrication of the detector chip. In this paper, we will present the simulation results for a Hartmann-Shack wavefront sensor with an orthogonal array of quad-cells (QC) integrated along with active-pixel (active-pixel sensor (APS)) circuitry and analog-to-digital converters (ADC) on a "complementary metal oxide semiconductor" (CMOS) process and deploying a modal wavefront reconstructor. This extended simulation capability for wavefront sensors enables the test and verification of different photosensitive and circuitry topologies for position-sensitive detectors combined with the simulation of sampling microlenses and reconstruction algorithms, with the goal of enhancing the accuracy in the prediction of the wavefront-sensor performance before a detector CMOS chip is actually fabricated.

3.
J Refract Surg ; 32(3): 193-200, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27027627

RESUMEN

PURPOSE: To analyze the optical performance of different implant strategies in simulated nanophthalmic eyes. METHODS: An optical design software was used. Analysis included eye models that required 30.00, 45.00, and 60.00 diopters (D) intraocular lenses (IOLs) to achieve emmetropia. Spherical and aspheric IOLs were designed. They were tested either with a single implant setting S or by splitting the power into two lenses. Setting P1 had an even split of the power between the lenses and setting P2 had an uneven power split with one-third of the power in the anterior lens and two-thirds in the posterior IOL. The area under the modulation transfer function (MTF) curve was calculated and spherical aberration was recorded in each setting. RESULTS: Setting S had the worst optical performance in the spherical group and the best performance in the aspheric group. A statistically significant difference was found between setting S and the piggyback options (settings P1 and P2) in all analyzed variables for the spherical and aspheric groups for the 45.00 and 60.00 D IOL requirement. No statistically significant difference was found between the piggyback settings. CONCLUSIONS: Single aspheric IOLs had better optical performance than piggybacking lower-power aspheric IOLs. In the spherical lenses group, the results were the opposite, with the piggyback options having higher optical quality than the single IOL. MTF shows that single aspheric lenses provide the highest contrast sensitivity among all of the analyzed settings.


Asunto(s)
Catarata/complicaciones , Implantación de Lentes Intraoculares , Lentes Intraoculares , Microftalmía/complicaciones , Modelos Teóricos , Óptica y Fotónica , Longitud Axial del Ojo/patología , Sensibilidad de Contraste/fisiología , Humanos , Facoemulsificación , Diseño de Prótesis , Visión Ocular/fisiología
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