Why is polycarbonate a good lens material for children and monocular patients?

• A. It is the lightest
• B. It is less expensive
• C. It is more impact-resistant than crown glass and CR-39
• D. It blocks UV completely

Answer: (C)

The main idea is safety through impact resistance. Polycarbonate’s standout property is its high ability to absorb and disperse energy from impacts, making lenses far less likely to crack or shatter compared with crown glass or CR-39. For children who are active and for monocular patients who rely on one eye, this reduces the risk of a lens fracture that could injure the eye or necessitate a replacement during critical times. This strong safety advantage is why polycarbonate is widely used for kids’ eyewear and safety lenses, often meeting strict impact standards. While it is lightweight and does provide UV protection, those benefits are secondary to its superior impact resistance.