Metodologia de otimização de lentes intraoculares monofocais e multifocais modeladas computacionalmente em modo não sequencial com base em algoritmo genético

• Ano de defesa: 2014
• Autor(a) principal: Luiz Melk de Carvalho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: NSGA-II; Lente multifocal; Algoritmo genético; Lente intraocular; Lente monofocal; Engenharia elétrica; Algoritmos genéticos; Lentes intra-oculares
• Link de acesso: http://hdl.handle.net/1843/BUOS-9UJP7Y

This paper presents a methodology for optimization of intraocular lenses (IOLs) using computational non-sequential modeling of the Zemax® software. The methodology discussed is based on the use of an optimization algorithm for global search called Non-dominating Sorting Genetic Algorithm II (NSGA-II) implemented in Matlab® software to optimize monofocal and multifocal IOLs' parameters. With respect to monofocal IOLs, which represents a mono-objective optimization problem, the NSGA-II algorithm has the task of finding the region of convergence to the global optimum of those lenses. This region allows it to be possible to achieve the best optical performance of the system (represented by its diffraction limit curve). Moreover, the robustness of the algorithm will be evaluated through the optimization of monofocal IOLs that exhibit deviations in its optical surface in order to simulate practical situations where there is an axis misalignment of the lathe that produces the surfaces of the lens. As for the multifocal IOLs, which represents multi-objective problems, the NSGA algorithm has the function of optimizing the system by presenting solutions that meet multiple requirements (the optical quality in its multiple focal points) according to the user's needs. The big advantage of this approach lies in the ability of the NSGA-II to deal with multi-objective problems and its ability to search the global optimal solutions than traditional deterministic methods that dont have such capability and flexibility. The results show that the NSGA-II was able to find the region of global optimum for all diopters of monofocal IOLs simulated and for those lenses that presented deviations on its surface it was possible to find solutions that showed a better optical quality than the spherical IOLs encountered in the market. Furthermore, the results indicate that the NSGA-II was able to optimize a refractive multifocal IOL that showed optical characteristics compatible with refractive multifocal IOLs marketed. This, therefore, validates the ability of the algorithm to solve mono- and multi-objective problems not only in the field of optics applied to IOLs, but in any area that performs activities related to the modeling of refractive and reflective optics in Zemax as, for example, camera lenses with industrial or entertainment application, microlens array for wavefront sensors, automotive lights etc.