What are the advantages and disadvantages of polycarbonate spectacle lenses?
Answer:
Polycarbonate lenses are made by injection moulding.
These lenses have good impact resistance, making them ideal for children, sports and industrial work. They also have good UV protection and a higher refractive index than CR39.
Disadvantages include the fact that their abrasion resistance is poor - adding an anti-scratch coating can help but reduces the impact resistance slightly. These types of lenses cannot be tinted easily, either.