Geometry-invariant GRIN lens: iso-dispersive contours
نویسندگان
چکیده
A dispersive model of a gradient refractive index (GRIN) lens is introduced based on the idea of iso-dispersive contours. These contours have constant Abbe number and their shape is related to iso-indicial contours of the monochromatic geometry-invariant GRIN lens (GIGL) model. The chromatic GIGL model predicts the dispersion throughout the GRIN structure by using the dispersion curves of the surface and the center of the lens. The analytical approach for paraxial ray tracing and the monochromatic aberration calculations used in the GIGL model is employed here to derive closed-form expressions for the axial and lateral color coefficients of the lens. Expressions for equivalent refractive index and the equivalent Abbe number of the homogeneous equivalent lens are also presented and new aspects of the chromatic aberration change due to aging are discussed. The key derivations and explanations of the GRIN lens optical properties are accompanied with numerical examples for the human and animal eye GRIN lenses.
منابع مشابه
Geometry-invariant gradient refractive index lens: analytical ray tracing.
A new class of gradient refractive index (GRIN) lens is introduced and analyzed. The interior iso-indicial contours mimic the external shape of the lens, which leads to an invariant geometry of the GRIN structure. The lens model employs a conventional surface representation using a coincoid of revolution with a higher-order aspheric term. This model has a unique feature, namely, it allows analy...
متن کاملAn analytical method for predicting the geometrical and optical properties of the human lens under accommodation.
We present an analytical method to describe the accommodative changes in the human crystalline lens. The method is based on the geometry-invariant lens model, in which the gradient-index (GRIN) iso-indicial contours are coupled to the external shape. This feature ensures that any given number of iso-indicial contours does not change with accommodation, which preserves the optical integrity of t...
متن کاملWide-field schematic eye models with gradient-index lens.
We propose a wide-field schematic eye model, which provides a more realistic description of the optical system of the eye in relation to its anatomical structure. The wide-field model incorporates a gradient-index (GRIN) lens, which enables it to fulfill properties of two well-known schematic eye models, namely, Navarro's model for off-axis aberrations and Thibos's chromatic on-axis model (the ...
متن کاملContribution of shape and gradient refractive index to the spherical aberration of isolated human lenses.
PURPOSE To estimate the contribution of 3-dimensional (3D) lens geometry and gradient refractive index (GRIN) to the lens spherical aberration (SA) with age. METHODS A total of 35 donor human lenses (19-71 years) were imaged with 3D-spectral optical coherence tomography (sOCT). Paraxial and nonparaxial back focal length were measured with laser ray tracing (LRT). The parameters of a 4-variabl...
متن کاملThree-dimensional reconstruction of the crystalline lens gradient index distribution from OCT imaging.
We present an optimization method to retrieve the gradient index (GRIN) distribution of the in-vitro crystalline lens from optical path difference data extracted from OCT images. Three-dimensional OCT images of the crystalline lens are obtained in two orientations (with the anterior surface up and posterior surface up), allowing to obtain the lens geometry. The GRIN reconstruction method is bas...
متن کامل