Sunglasses

The first sunglasses date back to the prehistoric Inuits, who wore a piece of flattened walrus ivory over their eyes. It contained narrow slits to look through, which blocked harmful rays of the sun reflecting off the ice.

The Roman Emperor Nero looked at the arena through a concave emerald during gladiatorial fights to eliminate the glare of the sun and his nearsightedness. Those may have been the first sunglasses in history.

Sunglasses made of rock crystal are supposed to have been first demonstrated in China, during the Ming dynasty. They were popular with judges who believe that the glasses hid what they were thinking. 

One of the earliest surviving depictions of a person wearing sunglasses is of the scientist Antoine Lavoisier in 1772. The picture below shows Lavoisier conducting an experiment related to combustion generated by amplified sun light.

Sunglasses as we know them started to become widespread in the 1920s, especially among movie stars. 

Inexpensive mass-produced sunglasses made from celluloid were first produced by Sam Foster in 1929. The first pair of Foster Grants were sold at Woolworths on the Atlantic City Boardwalk and Foster soon found a ready market on Atlantic City beaches They also become popular especially with aviators.

After leaving his thick eyeglasses on an airplane in 1963, while on tour with the Beatles, the singer Roy Orbison was forced to wear his prescription Wayfarer sunglasses on stage and found that he preferred them. They became part of his image and the (prescription) sunglasses indoors look was born.

Roy Orbison By Jac. de Nijs / Anefo - Nationaal Archief, 

In the 1970 Western film A Man called Horse starring Richard Harris, during a raid on the Red Indian Yellow Hands Camp, one of the braves can be seen wearing sunglasses. 

Business for Ray-Ban sunglasses was tanking in the 70s, so the company signed a product placement deal for 60 films. Risky Business, Top Gun, and Rain Man all had Tom Cruise wearing Wayfarers and Aviators, and sales went through the roof.

After the film Top Gun came out, sales of Ray-Ban Aviator sunglasses increased by 40%.

The Ray-Ban Predator 2 sunglasses worn by the original Men In Black tripled in sales to five million after the movie's 1997 release.

In 2011, police in Vietnam were banned from wearing black sunglasses on duty.

Cartier sunglasses (which retail for $2650 upwards) are a status symbol in Detroit. The Police in the city estimate there have been nine murders, seventeen non fatal shootings, and 2,158 robberies related to the glasses between 2012 and 2016.

U2's Bono is almost never seen in public without sunglasses, as he suffers from glaucoma and is sensitive to light.

Xiamen, China, is the world's largest producer of sunglasses, with its port exporting 120 million pairs each year. 

Pixiebay

An average of 210 pairs of sunglasses are turned in everyday at Disneyland and the Magic Kingdom.