Contact Lens Optics and Lens Design

It is always a pleasure to see a new book on ophthalmic optics, and particularly pleasing to see this volume on contact lens optics. Modern studies on contact lenses tend to concentrate on the influence of lenses on ocular physiology, so a book on the optical considerations is particularly welcome.

This volume is divided into 11 chapters, starting off with a welcome overview of basic visual optics. The second chapter then deals with basic paraxial lens optics and tear lens calculations, due consideration being given to soft, RGP and also scleral lenses.

Next there is a section on edge lift of lenses, also dealing with the calculation of edge and centre thickness.

As one might expect from a modern text on this subject, a chapter is devoted to aspheric surfaces, including offset and polynomial curves, and the influence of lens aberrations. The use of the p value for conic asphericity is used, as popularised by the late A G Bennett.