Contrary to what one might assume, the history of sunglasses didn't derive solely from the desire to shield the eyes from the sun. Much like one of their alternative uses today, the first documented purpose of sunglasses was to shield facial expressions instead of sunlight. Since then, sunglasses have been used for everything from blocking harmful rays while in outer space, to enabling the wearer to see through water.
Ray-Ban (short for banning sun rays), created the avator-style sunglasses made for pilots in the 30s.
One of the first concepts of sunglasses dates back to the 12th century, when court figures in China wore glasses with smoky quartz lenses in order to hide their facial expressions. In doing so, the judges could give the illusion of non-responsiveness to the testimonies, therefore not revealing their decision until the final verdict.
The first sunglasses made for the public came to light in the 18th century, when designer and inventor James Ayscough from England created eyeglasses with blue or green tints. Ayscough believed that the tint could improve vision, and he sold the shades for public use. Though his intention wasn't to block the sun, his invention was another building block in the history of sunglass design.
In the 19th century, a syphilis outbreak emerged in Europe. Yellow and brown-tinted sunglasses were prescribed to people who carried syphilis, to counteract one of the disease's symptoms of visual sensitivity to light.
The first milestone in sunglass popularity was started by Sam Foster in 1929. Foster, founder of Foster Grant eyewear, developed the first affordable sunglasses made for mass production. Foster sold sunglasses on the Atlantic City Boardwalk, and his products soon gained widespread popularity in America. The company continued to grow in popularity in the 1960s, with their "Who's That Behind Those Foster Grants?" campaign, which popularized the sunglasses with Hollywood celebrities.
Following the launch of Foster Grant sunglasses, the Army Air Corps worked with Bausch & Lomb in the 1930s to develop a sunglass lens specifically designed for pilots. Bausch & Lomb created a sunglass specific company call Ray-Ban (short for banning sun rays), which in turn created the aviator-style sunglasses made for pilots. Aviators incorporated polarized lenses with the help of Edwin H. Land (founder of Polaroid), and gained popularity when General Douglas MacArthur made a public appearance wearing a pair of Ray-Ban Aviators in the Philippines during WWII.
Through the mid to late 1900s, sunglasses continued to grow in popularity. Movies, musicians, and politicians that wore sunglasses in the public eye created a widespread consumer interest, and several other sunglass companies began to develop. The science of sunglass technology continued to prosper as well, as other features of mass-produced sunglasses began to materialize, like anti-reflective coating, anti-fog coating, shatter and scratch resistant lenses, UV protection, and others.