Most glasses are made of plastic lenses, or “organic glass” if you want to get fancy. So why are glasses lenses made of plastic? In most cases, they’re lighter than traditional glass lenses used in eyeglasses, which means they’re more comfortable to wear. It’s also easier to apply lens coatings like anti-glare to plastic lenses. And there’s a reason children’s cups are made of plastic: it’s more resistant to impact. There are four main types of plastics used to make eyeglass and sunglasses lenses: plastic, Trivex, polycarbonate and high-index plastics.

Plastic eyeglasses and sunglasses lenses

First up, we have basic plastic lenses which are made from CR-39, a plastic polymer. CR-39 is an abbreviation for “Columbia Resin #39”, the 39th plastic of that type made by Columbia Resin, the company that developed the polymer.

After that, we have polycarbonate glasses lenses. A synthetic plastic discovered in the 1890s, polycarbonates became out of this world once they found use in aeronautics. Polycarbonate is a type of plastic that can be produced as transparent and easily shaped, making it great for optical (glasses) lenses. It’s also impact resistant, meaning they’re a good lens choice for kids (or adults!) who tend to be accident prone. Similar to polycarbonate, Trivex glasses lenses are made of impact resistant urethane based pre-polymer plastic. Aside from both being impact resistant, Trivex and polycarbonate lenses have 100% UV protection.

Finally, there’s high-index plastics. The plastics used for this type of lens often contain sulfur. The atoms of this odorous element help these lenses have a higher refractive index, meaning a thinner lens. Although high-index lenses may be thinner, they’re heavier due to the higher density of these plastics.

How are eyeglass lenses made?

1. Eyeglass lenses are first made by a lab technician reviewing your prescription and taking a lens bank (a curved glass or plastic disc that is the basis of the lens) that closest matches your prescription.
2. The technician puts the lens bank into a grinding machine and grinds it into a shape that matches your prescription even closer
3. Then, the lenses are edged and cut into a shape that fits the frame you chose
4. Afterwards, the neatly cut lenses are dipped in a solution that protects them from scratches, gives them a tint, or more!

What you need to know about glasses lenses

First of all, getting the right lens coatings can make a world of difference in your lenses, no matter what they’re made of. That’s why Mahdi Opticals offers a wide selection of coatings to help protect your eyes and your lenses. In fact, your lenses are so important to us that we offer a buy one get one free! Want to know more about out lenses?

Call us on 0742000498.