Optics of phakic, pseudophakic, and aphakic eyes: effects on the Stiles-Crawford (SCE I) function.

In many experimental situations one has to work with suitable optical corrections for ocular elements which have been eliminated (lens in aphakia, for example). Analysis of the optics of the total system (eye plus correction and other optical elements) shows substantial changes in the positions of the cardinal points. These changes are meaningful and must be taken into account in subsequent analysis. We discuss the pertinent optical considerations and show as an example the results of measurements of the Stiles-Crawford effect of the first kind in an aphakic subject with spectacle and contact lens correction.