Lens design software once was characterized by large, expensive and user-unfriendly programs running on large, expensive and painfully slow mainframe computers. Lens design was almost exclusively the domain of dedicated professionals in classical design techniques. Now, even the term “lens design” has changed, giving way to the more generic “optical design,” and systems are as likely to be rotationally symmetrical as not. Modern designers use an array of components -- gradient index lenses, diffractive optics, wild aspherics, non-rotationally symmetric surfaces, faceted surfaces, lens arrays, diffusers and others…