Ray tracing error correction in ophthalmic optics.

ABSTRACT

Ray tracing error correction (RTEC), a new method for various refractive calculations, is introduced. It consists of two procedures (1) ray tracing that determines whether the ray originating from an infinite point focuses on the fovea and (2) error correction that varies the curvature of the different refractive surfaces according to an error correction formula when the ray is not focused at the fovea. These calculations are continued until the ray is focused at the fovea. The refraction of Gullstrand's schematic eye at relaxation and at accommodation, the desired postoperative corneal curvature for postoperative emmetropia after corneal ablation surgery, and the intraocular power of convex-plano, biconvex, and plano-convex intraocular lenses are presented.