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Nonlinear equations for calculating lens parameters based on Scheimpflug photographs: preliminary results
1Knoll AG, Ludwigshafen, FRG.
Abstract:
Real lens diameter and real lens volume cannot be measured by Scheimpflug photography, but the apparent lens radii and the lens thickness (anterior and posterior) can. Some stereometric equations allow us to calculate lens volume and lens diameter. Equations for the adaptation of the data points to nonlinear curves are given. There are no linear but sigmoid relationships between the age-dependent parameters. These can be estimated with the aid of equations 2 and 3 presented in this paper. When carrying out further investigations a greater number of parameters should be included in the analysis. It is conceivable that the equations must be expanded in order to be able to take other important parameters into consideration. Preliminary results of the calculations with regard to age are reported.
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