Benjamin Franklin's invention of bifocal lenses occurred in 1780. By the 20th Century, sunglasses were used to protect the eyes from the sunshine. In 1929 Sam Foster began selling his protective sunglasses at Woolworth stores on the boardwalk at the beaches in Atlantic City and New Jersey.
Foster detected a ready marketplace on the beaches of Atlantic City, New Jersey, where he began selling sunglasses under the name Foster Grant from a Woolworth on the Boardwalk.
The chemical filter on the lenses of polarized sunglasses is designed to absorb horizontal sun waves, while still letting horizontal waves to pass through. Because light can only travel in one direction through polarized lenses, glare is removed.
Glare is a riling and sometimes dangerous intensity of sun that we experience as humans. Polarized sunglasses cut glare and haze so your eyes are more comfortable and you can see better. Polarized lenses contain a special filter that blocks this type of intense reflected light, reducing glare.
Your cornea can typically absorb all of this light, but they can sometimes penetrate to the lens of your eye. This prolonged exposure can eventually form cataracts or even cause eye cancer. Sunglasses protect your eyes by assimilating the UV wavelengths, which is done by applying a UV coating to the lenses.
We recommend wearing sunglasses whenever you go outside for a prolonged period, this includes cloudy days.