Energy efficiency of a new trifocal intraocular lens

The light distribution among the far, intermediate and near foci of a new trifocal intraocular lens (IOL) is experimentally determined, as a function of the pupil size, from image analysis. The concept of focus energy efficiency is introduced because, in addition to the theoretical diffraction effic...

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Detalles Bibliográficos
Autores: Vega Lerín, Fidel|||0000-0002-8594-0872, Alba Bueno, Francisco, Millán Garcia-Varela, M. Sagrario|||0000-0001-6950-2373
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/22586
Acceso en línea:https://hdl.handle.net/2117/22586
https://dx.doi.org/10.2971/jeos.2014.14002
Access Level:acceso abierto
Palabra clave:Intraocular lenses
Diffraction
Cataract
Eye--Models
Eye--Accommodation and refraction
Diffraction efficiency
Eye model
Trifocal intraocular lens
Lents intraoculars
Difracció
Ulls -- Acomodació i refracció
Cataractes (Oftalmologia)
Àrees temàtiques de la UPC::Ciències de la visió::Instruments òptics i optomètrics::Lents oftàlmiques
Àrees temàtiques de la UPC::Ciències de la visió::Òptica física::Òptica geomètrica
Descripción
Sumario:The light distribution among the far, intermediate and near foci of a new trifocal intraocular lens (IOL) is experimentally determined, as a function of the pupil size, from image analysis. The concept of focus energy efficiency is introduced because, in addition to the theoretical diffraction efficiency of the focus, it accounts for other factors that are naturally presented in the human eye such as the level of spherical aberration (SA) upon the IOL, light scattering at the diffractive steps or the depth of focus. The trifocal IOL is tested in-vitro in two eye models: the aberration-free ISO model, and a so called modified-ISO one that uses an artificial cornea with positive spherical SA in instead. The SA upon the IOL is measured with a Hartmann-Shack sensor and compared to the values of theoretical eye models. The results show, for large pupils, a notorious reduction of the energy efficiency of the far and near foci of the trifocal IOL due to two facts: the level of SA upon the IOL is larger than the value the lens is able to compensate for and there is significant light scattering at the diffractive steps. On the other hand, the energy efficiency of the intermediate focus for small pupils is enhanced by the contribution of the extended depth of focus of the near and far foci. Thus, while IOLs manufacturers tend to provide just the theoretical diffraction efficiency of the foci to show which would be the performance of the lens in terms of light distribution among the foci, our results put into evidence that this is better described by using the energy efficiency of the foci.