Semi finished prescription PC 1.59 polycarbonate HC HMC ophthalmic lens for optical lab

Polycarbonate(PC) lenses are lighter and thinner than regular plastic eyeglass lenses. But they are up to 10 times more impact-resistant than traditional plastic lenses and they can offer 100 percent UV protection. All these make polycarbonate lenses an excellent choice for safety glasses, children's glasses, sports eyewear.

1. Impact Resistant   Polycarbonate material was originally made for uses on canopies covering fighter planes and then made its way into space on astronaut visors and space shuttle windshields. Today it is readily available to the public. It impact resistance makes the material extremely suitable for sports, industrial safety goggles, and children's eyewear.

2. Scratching Resistant   The reason for polycarbonate lenses' impact resistance is because of its "softness". Softer materials will flex instead of fragment when met with great force. However, the property allows lenses to be scratched easily. Therefore, every single one of our polycarbonate lenses is multi-coated with hard coating that forms a protective layer around the lenses allowing the lenses to be free from scratches while retaining its impact resistant qualities.

Semi-finished lens is the raw blank used to produce the most individualized RX lens according to thepatient's prescription. Different prescription powers request for different semi-finished lens types or base curves.

The semi-finished lenses are produced in a casting process. Here, liquid monomers are first poured into moulds. Various substances are added to the monomers, e.g. initiators and UV absorbers. The initiator triggers a chemical reaction that leads to hardening or "curing" of the lens, while the UV absorber increases the UV absorption of the lenses and prevents yellowing.