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.