Some of the basics about lens materials, and what has gone intocreating them

摘要

Sixty-five years ago, only one lens material was available—glass. During World War II, acrylic lenses made of polymethyl methacrylate, the same material that would later be used to fabricate hard contact lenses, came to market but were unsuccessful because the material was brittle, difficult to fabricate, and easily scratched. Then, in 1945, CR-39, a hardresin polymer, became the first plastic lens material used in the industry.