Sunglasses prevent you from sunlight.
Sunglasses or sun glasses are a form of protective eyewear designed primarily to prevent bright sunlight and high-energy visible light from damaging or discomforting the eyes. They also help cancel out harmful UV rays from the sun. They can sometimes also function as a visual aid, as variously termed spectacles or glasses exist, featuring lenses that are colored, polarized or darkened. In the early 20th century they were also known as sun cheaters.
Precursors
Inuit snow goggles function by reducing exposure to sunlight, not by reducing its intensity
In prehistoric and historic time, Inuit peoples wore flattened walrus ivory "glasses," looking through narrow slits to block harmful reflected rays of the sun.
James Ayscough began experimenting with tinted lenses in spectacles in the mid-18th century, around 1752. These were not "sunglasses" as such; Ayscough believed blue- or green-tinted glass could correct for specific vision impairments. Protection from the Sun's rays was not a concern for him.
Yellow/amber and brown-tinted spectacles were also a commonly-prescribed item for people with syphilis in the 19th[dubious – discuss] and early 20th centuries because sensitivity to light was one of the symptoms of the disease.
Modern developments
In the early 1900s, the use of sunglasses started to become more widespread, especially among stars of movies. It is commonly believed that this was to avoid recognition by fans, but an alternative reason sometimes given is that they often had red eyes from the powerful arc lamps that were needed due to the extremely slow speed film stocks used.[citation needed] The stereotype persisted long after improvements in film quality and the introduction of ultraviolet filters had eliminated this problem. Inexpensive mass-produced sunglasses were introduced to America by Sam Foster in 1929. Foster found a ready market on the beaches of Atlantic City, New Jersey, where he began selling sunglasses under the name Foster Grant from a Woolworth on the Boardwalk.
Functions of sunglasses
While non-tinted glasses are very rarely worn without the practical purpose of correcting eyesight or protecting one's eyes, sunglasses have become popular for several further reasons, and are sometimes worn even indoors or at night.
Sunglasses can be worn to hide one's eyes. They can make eye contact impossible, which can be intimidating to those not wearing sunglasses; the avoided eye contact can also demonstrate the wearer's detachment,[citation needed] which is considered desirable ("cool") in some circles. Eye contact can be avoided even more effectively by using mirrored sunglasses. Sunglasses can also be used to hide emotions; this can range from hiding blinking to hiding weeping and its resulting red eyes. In all cases, hiding one's eyes has implications for nonverbal communication.
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| Artist M.I.A. wearing sunglasses as part of her costume for the Outside Lands Music and Arts Festival. |
Fashion trends can be another reason for wearing sunglasses, particularly designer sunglasses. Sunglasses of particular shapes may be in vogue as a fashion accessory. Fashion trends can also draw on the "cool" image of sunglasses.
People may also wear sunglasses to hide an abnormal appearance of their eyes. This can be true for people with severe visual impairment, such as the blind, who may wear sunglasses to avoid making others uncomfortable. The assumption is that it may be more comfortable for another person not to see the hidden eyes rather than see abnormal eyes or eyes which seem to look in the wrong direction. People may also wear sunglasses to hide dilated or contracted pupils, bloodshot eyes due to drug use, recent physical abuse (such as a black eye), exophthalmos (bulging eyes), a cataract, or eyes which jerk uncontrollably (nystagmus).
Teashades
"Teashades" (sometimes also called "John Lennon glasses", "Ozzy Glasses", after Ozzy Osbourne or, occasionally, "Granny Glasses") were a type of psychedelic art wire-rim sunglasses that were often worn, usually for purely aesthetic reasons, by members of the 1960s counterculture, as well as by opponents of segregation.[citation needed] Pop icons such as Mick Jagger, Roger Daltrey, John Lennon, Jerry Garcia, Boy George, Liam Gallagher and Ozzy Osbourne, all wore teashades. The original teashade design was made up of medium-sized, perfectly round lenses, supported by pads on the bridge of the nose and a thin wire frame. When teashades became popular in the late 1960s, they were often elaborated: Lenses were elaborately colored, mirrored, and produced in excessively large sizes, and with the wire earpieces exaggerated. A uniquely-colored or darkened glass lens was usually preferred. Modern versions tend to have plastic lenses, as do many other sunglasses. Teashades are hard to find in shops today; however, they can still be found at many costume Web sites and in some countries.
The term has now fallen into disuse, although references can still be found in literature of the time. "Teashades" was also used to describe glasses worn to hide the effects of marijuana (conjunctival injection) or bloodshot eyes or the effects of opiates such as heroin (pupillary constriction).
The glasses worn by Seraph in the Matrix films are teashades. Teashades are briefly referenced during a police training seminar in Hunter S. Thompson's novel Fear and Loathing in Las Vegas. Mickey Knox in Natural Born Killers wears red teashades. Lara Croft from the video-game Tomb Raider is seen wearing Teashade sunglasses. Vash the Stampede (Trigun) wears yellow-lens teashades. The iconic sunglasses of Spider Jerusalem are a variation of teashades. Jean Reno wears black teashades in the movie Léon(The Professional). Main character of Hellsing, Alucard, wears red-lensed teashades. Recently, actress and fashion icon Mary-Kate Olsen and pop music singer Lady Gaga have been seen wearing several variations of teashades. Howard Stern was also known for wearing teashades in the early to mid 90's and never taking them off in public.
