Everyday stuff

Sunglasses

Sunglasses are used to prevent exposure to the ultraviolet radiation from the sun. But yes, they also make a style statement! They are popularly used as a fashion accessory. They have always been associated with celebrities and film personalities who make use of the glasses to hide their identity.

Back in the 12th century, sunglasses made from flat panes of smoky quartz were supposedly used in China. These glasses did not provide corrective vision but were helpful in blocking out the glare from the sun. Ancient documents describe the use of these sunglasses by judges in Chinese courts to conceal their facial expressions while questioning witnesses.

The glasses with tinted lenses, which could be called the precursors to the modern sunglasses, were introduced by James Ayscough. He believed that blue or green tinted glasses could be used to correct certain vision impairments. He began experimenting with tinted lenses around 1752. Yellow and brown tinted glasses were commonly prescribed for people suffering from syphilis owing to the fact that the disease caused sensitivity to light.

Sunglasses made from celluloid were first mass produced by Sam Foster in 1929. He sold them commercially on the boardwalk along the beaches of Atlantic City, New Jersey. Sunglasses soon became popular among actors who would wear them to protect themselves from the harsh lights of the movie sets.

In 1936, Edwin H. Land patented his Polaroid filter and polarized sunglasses soon became available in the market which protected against harmful ultraviolet radiation.

 

References
  1. https://en.wikipedia.org/wiki/Sunglasses
  2. http://optical.com/sunglasses/history-of-sunglasses/
  3. http://www.glasseshistory.com/glasses-inventor/who-invented-sunglasses/
  4. http://www.ideafinder.com/history/inventions/sunglasses.htm