Hi all,

I need to make two models of reading glass lens. One is 1.75 diopter the other 2.5. Client wants to use aspherical lens surface curvature due to limitataions of thickness.

-help-

He has provided the formula but I can't seem to get it to work. I don't work often enough in the surface world and I know this is a factor in not seeing my errors.

=R-(R^2-r^2)^0.5+Br^4

Even if you can help without the formula and create 1.75 ashperical, then that would be great and using that example I can do the rest of the work.

Many thanks in adance

My first thought is that I really don't know the terms relating eyewear! But I have few questions from messing with your model.

I know you were looking for a plano convex but I found making a meniscus with the formerly plano surface having a large radius worked well. My lens came up with a FL of 571mm (dioptre = (1/571)x1000=1.751. Curves are R1 = 294.75mm, Conic = -1.05; R2 = 2500mm, Conic = -.9; Center thickness = 1.5mm. Material is PC. Lens shape cutout is centered on the revolve.