For the lenses of reading glasses two production processes are common. The Polymethylmethacrytal (PMMA), colloquially also called "acrylic glass", can be compared to normal mineral glass, but lighter and more impact resistant. There is also no danger of splintering at moderate impact energies and velocities.
Polycarbonate lenses (PC) are used mainly for sports glasses and children's glasses. They are characterized by extremely high fracture resistance and are often provided with particularly effective protection against UV rays. PC is a chemical compound used in both windows or conservatories, but also used in the production of mobile phone cases. In order to increase the scratch resistance, high-quality plastic lenses are coated with a special hard lacquer.