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Theoretical calculation of a contact lens thickness designed to correct the eye's monochromatic aberrations
José B Almeida1, Arlindo M Fontes Garcia
1Departamento de Física, Universidade do Minho, Braga, Portugal.
Purpose:
The aim of this work is the theoretical study of high order aberration compensation in the human eye.
Methods:
This compensation should be achieved with uneven thickness contact lenses (rigid gas permeable or soft), capable of inducing a localized delay on the aberrated wavefront, so that light beams originated on a point object would reach the retina at a common point, irrespective of their point of passage through the pupil.
Results:
The algorithm for optimal local contact lens thickness determination is explained. For this purpose the aberrated wavefront measured on a patient by the double-pass technique was expressed in terms of Zernike polynomials. The knowledge of the wave aberration as a function of the point of passage through the pupil allows determination of the delay to be introduced in order to produce a wavefront as would result from non-aberrated eye, where all rays would reach the same point on the retina.
Conclusions:
The explanation of how it would be possible to correct wavefront deviations, by varying an RGP or soft contact lens thickness, was made, and a particular eye exemplify.
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