The purpose of this thesis is to describe the development of an anatomically based, young adult eye model, which includes a crystalline lens with a gradient refractive index (GRIN). This model will then be used to investigate the effect of laser refractive surgery. The first step in this process involved developing a symmetrical eye model that was found to be a better predictor of empirical longitudinal spherical aberration than any previous model. Myopia was simulated by either a purely axial or refractive technique. While these models were found to be good predictors of the spherical aberration measured in young adults, they did not predict the total amount of high-order aberrations. The techniques used to simulate a single type of myopia caused the myopic models to become anatomically inaccurate. To improve the eye models a biconic surface was used to quantify the anterior corneal shape as a function of myopia. A method to describe the refractive error and biconic shape parameters in Jackson Cross Cylinder terms was implemented to determine correlations. Results indicate that a biconic accurately models the average shape of the anterior corneal surface as a function of myopia. Adopting the biconic model for the anterior corneal surface and adding average misalignments of the ocular components transformed the models from symmetrical to asymmetrical. Refractive error was now simulated by the anatomically accurate changes in both the anterior corneal shape and axial length. The asymmetrical aberrations resulted from the misalignment of the ocular components and provided a good prediction of average empirical aberrations but underestimated the aberrations of individual subjects. Photorefractive keratectomy, a form of laser refractive surgery, was simulated by theoretically calculated and by empirically measured changes in the shape of the anterior corneal surface. Applying the change in anterior corneal shape to the asymmetrical models was used to develop postoperative models. Changes in corneal shape and model aberrations attributed to theoretical calculations do not match empirical observations. The prediction of increased high-order aberrations in postoperative models based on empirically measured changes in the anterior corneal topography was similar to clinical results. Average anatomically based, GRIN eye models have been developed that accurately predict the average aberrations of emmetropic and myopic young adults. These models underestimate the asymmetrical and total high-order aberrations that have been measured in individual subjects but are still useful for investigating the average effects of procedures like refractive surgery.

The purpose of this thesis is to describe the development of an anatomically based, young adult eye model, which includes a crystalline lens with a gradient refractive index (GRIN). This model will then be used to investigate the effect of laser refractive surgery. The first step in this process involved developing a symmetrical eye model that was found to be a better predictor of empirical longitudinal spherical aberration than any previous model. Myopia was simulated by either a purely axial or refractive technique. While these models were found to be good predictors of the spherical aberration measured in young adults, they did not predict the total amount of high-order aberrations. The techniques used to simulate a single type of myopia caused the myopic models to become anatomically inaccurate. To improve the eye models a biconic surface was used to quantify the anterior corneal shape as a function of myopia. A method to describe the refractive error and biconic shape parameters in Jackson Cross Cylinder terms was implemented to determine correlations. Results indicate that a biconic accurately models the average shape of the anterior corneal surface as a function of myopia. Adopting the biconic model for the anterior corneal surface and adding average misalignments of the ocular components transformed the models from symmetrical to asymmetrical. Refractive error was now simulated by the anatomically accurate changes in both the anterior corneal shape and axial length. The asymmetrical aberrations resulted from the misalignment of the ocular components and provided a good prediction of average empirical aberrations but underestimated the aberrations of individual subjects. Photorefractive keratectomy, a form of laser refractive surgery, was simulated by theoretically calculated and by empirically measured changes in the shape of the anterior corneal surface. Applying the change in anterior corneal shape to the asymmetrical models was used to develop postoperative models. Changes in corneal shape and model aberrations attributed to theoretical calculations do not match empirical observations. The prediction of increased high-order aberrations in postoperative models based on empirically measured changes in the anterior corneal topography was similar to clinical results. Average anatomically based, GRIN eye models have been developed that accurately predict the average aberrations of emmetropic and myopic young adults. These models underestimate the asymmetrical and total high-order aberrations that have been measured in individual subjects but are still useful for investigating the average effects of procedures like refractive surgery.

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Les traitements antireflets (AR) sont très largement utilisés pour améliorer la transmission de systèmes optiques composés de hublots, lentilles, de lames séparatrices,… Dans cette thèse les gammes spectrales visées sont le visible étendu [400-1800nm] et le moyen infrarouge [3,7-4,8µm]. La méthode de nanostructuration par dépôts de films minces utilisant des techniques PVD en incidence oblique (Oblique Angle Deposition) a été choisie car elle permet d’envisager des AR hautes performances sur une large gamme de longueur d’onde, via un procédé industrialisable. L’introduction de porosité via le contrôle des angles de dépôt est utilisée pour nanostructurer l’architecture de chaque couche et de l’empilement ; méthode permettant de modifier et d’optimiser les propriétés optiques des couches constituantes en vue d’un design complet optimal. Une cartographie des indices effectifs accessibles par OAD a été dégagée concernant les trois matériaux déposés (TiO2, SiO2 et Ge). Mais les propriétés optiques de ces couches nanostructurées diffèrent largement de celles des couches denses du fait de la présence d’anisotropie, de gradient d’indice, de diffusion et d’absorption. A partir de caractérisations microstructurales, chimiques et optiques poussées (AFM, MEB, MET, tomographie FIB, tomographie MET, EDX, EELS, spectrophotométrie et ellipsométrie généralisée) un modèle optique analytique plus complexe et couplé à des analyses par éléments finis (FDTD) est présenté. L’ensemble du travail a permis d’élaborer par OAD de simples antireflet bicouches démontrant déjà de hauts niveaux de transmission, supérieurs aux traitements AR existants (interférentiel) ou en développement (Moth-eyes). / Anti-reflective (AR) coatings are widely used to improve the transmission of optical systems composed of window, lenses, separating filters,... In this thesis, the spectral ranges targeted are the extended visible [400-1800nm] and the mid infrared [3.7-4.8µm]. Thin film deposition nanostructuring method using oblique angle deposition (oblique angle deposition) PVD technique was chosen because it allows high performance AR to be considered over a wide wavelength range, by an industrial process. The introduction of porosity with the control of deposition angle is used to nanostructure the architecture of each layer and stack; a method for modifying and optimizing the optical properties of the constituent layers for optimal complete design. A mapping of the effective indices accessible by OAD has been identified for the three materials deposited (TiO2, SiO2 and Ge). However optical properties of these nanostructured layers differ greatly from those of dense layers due to the presence of anisotropy, index gradient, diffusion and absorption. Based on advanced microstructural, chemical and optical characterizations (AFM, SEM, TEM, FIB tomography, TEM tomography, EDX, EELS, spectrophotometry and generalized ellipsometry) a more complex analytical optical model coupled with finite element analyses (FDTD) is presented. All the work has enabled OAD to develop simple two-layer anti-reflective coatings that already demonstrate high levels of transmission, superior to existing (interferential) or work in progress (Moth-eyes) AR treatments.