The first sunglasses were invented sometime in 12th century China. They were a crude slab of smoked quartz that was made to block out the light from the sun. The primitive frames were roughly shaped frame to hold them against the user's face. These darkened lenses, made only for the very rich, were not vision-corrected, nor they protect against harmful UV rays, but they provided some relief from having the bright sun constantly shining into user's eyes and were also used to hide emotions from others when speaking with them. This was particularly handy for Chinese judges of that time who had routinely worn smoke-colored quartz lenses allowing them to see emotionally detached from the topic being discussed and to conceal their feelings while questioning the accused.
Around 1430 vision-correcting eyeglasses were darkened and they were introduced into Italy via the Chinese.
In the 18th century James Ayscough began experimenting with tinted lenses in spectacles but not to protect from the sun's rays but to improve vision for those with poor or failing eye sight. He believed that by changing the color of the lenses to a blue/green tint, he could correct specific vision impairments.
The modern-type sunglasses appeared in the 20th century. They became very popular when Hollywood stars began using them to shield their eyes from the bright studio lights. In 1929, Sam Foster, founder of the Foster Grant of Atlantic City , had put sunglasses into mass production in America and was doing a roaring trade through his company. He sold the first pair of Foster Grant sunglasses on the Boardwalk in Atlantic City, NJ in 1929. By 1930, sunglasses could be found in all the range.
In the 1930s, the Army Air Corps commissioned the optical firm of Bausch & Lomb to create effective eyeglasses to protect pilots from high altitude glare. Company physicists and opticians perfected a special dark-green tint that absorbed light in the yellow band of the spectrum.
In 1936, Polaroid filters had been invented by Edwin H. Land, founder of the Polaroid Corporation, allowing glasses to protect against harmful UV rays for the first time, and making a desirable item for health aid as well as for reasons of fashion and comfort.
With World War II brewing in 1936, Ray Ban designed anti-glare aviator glasses, using new polarized lens technology created by Edwin H. Land and a year later the public was able to purchase the model that banned the sun's rays as Ray-Ban aviator sunglasses.
A clever 1960s' style advertising campaign by the comb and glass firm of Foster Grant made sunglasses very trendy. During '70s well-known fashion designers and Hollywood stars escalated the sunglass craze with their brand-name lines.