If you are financially constrained, buy a cheap used physical copy of the 2nd edition for the core math, and use the library’s eBook portal for the 3rd edition’s updates on progressive lenses.
: In-depth coverage of Aspheric lenses , Progressive Power Lenses (PPLs) , and Specialized lenses for sports and safety. ophthalmic lenses and dispensing mo jalie pdf
Jalie's work is particularly noted for its coverage of complex lens types: Progressive Power Lenses (PALs): If you are financially constrained, buy a cheap