All good sunglasses have these five things

Lens layers, like an onion.
Sunglasses
Means to a lens. Sam Kaplan

Share

We may earn revenue from the products available on this page and participate in affiliate programs. Learn more ›

Means to a lens
Means to a lens. Sam Kaplan

Almost any pair of sunglasses, even those cheap gas-station shades, can make you instantly look cooler. Decidedly uncool are the benefits that single-digit spectacles can’t afford—like cutting down on glare on sunny or snowy days, and preventing UV rays from slowly cooking your eyeballs. Luxottica, the company behind Ray-Ban and its iconic Wayfarers, has a very particular recipe for the sandwiched stack of materials that make up its Sun RX prescription lenses.

Layer 1: Scratch-Resistant Shell

Ray-Ban encases the entire lens in a layer of silicone resin to protect the surface from scratches and nicks. Applied via wet-bath for uniform coverage, the coating hardens under heat and UV light.

Layer 2: Colored Tint

Rather than tinting the lens itself—which could lead to uneven coloration as a result of the prescription-cutting process—Ray- Ban applies color as a separate polycarbonate layer. Dyes mix with the molten raw material prior to molding.

Layer 3: Polarizing Film Light reflecting off flat surfaces such as lakes and roads oscillates horizontally, creating glare in situations where sunglasses matter most. A thin layer of polyvinyl alcohol with a series of microscopic vertical slits stretches across the lens, canceling out (or polarizing) the harsh light.

Layer 4: Prescription Lens A computer-guided diamond cutter contours polycarbonate lenses to ‘script-perfect magnification. The impact-resistant material filters vision-impairing UV light and is roughly half the weight of hardened glass common in other shades.

Layer 5: Anti-Reflective Coating

A dark, shiny surface tends to act like a mirror, especially in bright sun. To combat this effect, invisible layers of silica oxide, titanium oxide, and zirconium oxide bounce light in a different directions, keeping reflections of your face out of sight.

This article originally appeared in the Extreme Weather issue of Popular Science.

 

Win the Holidays with PopSci's Gift Guides

Shopping for, well, anyone? The PopSci team’s holiday gift recommendations mean you’ll never need to buy another last-minute gift card.