Les
Well-Known Member
I wonder if "conza lens" is the term for a stepped lens that was prefered by some to prevent confusion with a fresnel lens which might also be described as stepped (the difference between the two being which side of the lens is stepped).
Perhaps. I will note that Altman's conza lens is sort of a modified step lens (touched on above). There are very slight lenticular ripples on the convex side of the lens.