The optical theory behind a new technique for reshaping the cornea to correct refractive errors of the eye is presented. This technique is capable of excising both positive and negative meniscus (lenticular)-shaped tissues of predetermined optical power from the anterior cornea. The optical lens bending theory routinely used by optical designers to reduce the amount of spherical and comatic aberrations in a lens system is employed in this technique. This technique uses a microkeratome to remove a planoconvex, or planoconcave-shaped tissue from the cornea while the eye is in a deformed state. When the eye returns to its natural, undeformed state, a lenticular tissue of predetermined optical power has been removed, correcting for myopic or hyperopic refractive errors, respectively. An elementary introduction to the current surgical techniques used for the correction of refractive errors is presented. Meniscus cross sections of the excised tissues are shown to demonstrate the optical theory discussed.
Russell G. Koepnick,
Perry S. Binder,
Harry S. Geggel,
"New method for reshaping the cornea," Journal of Biomedical Optics 2(1), (2 January 1997). http://dx.doi.org/10.1117/12.260020