Evaluating ophthalmic progressive addition lens designs with freeform surfaces and gradient index optics

Abstract

A raytrace method is developed for evaluation of progressive addition lens (PAL) designs with freeform surfaces and gradient index (GRIN) profiles. The raytrace analysis is adapted from a Hartmann test method. More common surface-geometric evaluations for freeform surface PAL designs are presented for comparison. Sur- face geometric and real raytrace methods are compared for evaluation of homogeneous freeform surface PALs. Raytrace evaluation is compared with evaluation results from commercial lens design software for single vision lenses. A GRIN PAL base design is evaluated using the real raytrace method, and characteristic PAL behavior is demonstrated. This raytrace evaluation method enables new directions in using GRIN for ophthalmic lenses.