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Sunglasses or sun glasses are a visual aid, variously termed spectacles or
glasses, which feature lenses that are coloured or darkened to prevent strong
light from reaching the eyes. In the early Twentieth century they were also
known as sun cheaters (or simply cheaters).
Many people find direct sunlight too bright to be comfortable. During outdoor
activities, the human eye can receive more light than usual. Healthcare
professionals recommend eye protection whenever outside to protect the eyes from
ultraviolet radiation, which can lead to the development of a cataract.
Sunglasses have long been associated with celebrities and film actors primarily
from a desire to hide or mask their identity. Since the 1940s sunglasses have
been popular as a fashion accessory, especially on the beach.
Contents
[hide]
1 History
1.1 Precursors
1.2 Modern developments
2 Uses
2.1 Visual clarity and comfort
2.2 Protection
2.3 Standards
3 Water sunglasses
4 Construction
4.1 Lens
4.2 Frames
4.3 Nose Bridge
5 Fashion
5.1 Oversized sunglasses
5.2 Onassis glasses
5.3 Mirrorshades
5.4 Aviators
5.5 Wayfarers
5.6 Teashades
5.7 Shutter Shades
5.8 Glacier Glasses
5.9 Faded/ Graduated Lenses
5.10 Fashion
6 Other names for sunglasses
7 Notes and references
8 External links
It is said that the Roman emperor Nero liked to watch gladiator fights with
emeralds. These, however, appear to have worked rather like mirrors.[1] Flat
panes of smoky quartz which offered no corrective powers but did protect the
eyes from glare were used in China in the 12th century or possibly earlier.
Contemporary documents describe the use of such crystals by judges in Chinese
courts to conceal their facial expressions while questioning witnesses.[2]
James Ayscough began experimenting with tinted lenses in spectacles in the
mid-18th century. 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 of his.
Yellow/Amber and brown-tinted spectacles were also a commonly-prescribed item
for people with syphilis in the 19th and early 20th centuries because of the
sensitivity to light that 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 the pioneering stars of silent movies. It is commonly believed
that this was to avoid recognition by fans, but the real reason was they often
had perennially 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.
Sunglasses first became polarized in 1936, when Edwin H. Land began
experimenting with making lenses with his patented Polaroid filter.
Hiding one's eyes has implications in face-to-face communication: It can hide
weeping, being one of the signs of mourning, makes eye contact impossible which
can be intimidating, or can show detachment, which is considered cool in some
circles. Darkened sunglasses of particular shapes may be in vogue as a fashion
accessory. Note that normal glasses are very rarely worn without a practical
purpose — curiously, they can project an image of uncool nerdiness that
sunglasses do not have. The impact on nonverbal communication and the cool image
are among the reasons for wearing sunglasses by night or indoors. People may
also wear sunglasses to hide dilated or contracted pupils or bloodshot eyes
(which would reveal drug use), recent physical abuse (such as a black eye), or
to compensate for increased photosensitivity. Fashion trends are another reason
for wearing sunglasses, particularly designer sunglasses. Shutter Shades are a
prime example of sunglasses worn for fashion rather than functionality due to
trends in pop culture.
People with severe visual impairment, such as the blind, often wear sunglasses
in order to avoid making others uncomfortable — not seeing eyes may be better
than seeing eyes which seem to look in the wrong direction. Those whose eyes
have an abnormal appearance (for example due to cataract) or which jerk
uncontrollably (nystagmus) may also do so.
Visual clarity and comfort
Sunglasses can improve visual comfort and visual clarity by protecting the eye
from glare.[3] Various types of disposable sunglasses are dispensed to patients
after receiving mydriatic eye drops during eye examinations.
Protection
Excessive exposure to ultraviolet radiation (UV) can cause short-term and
long-term ocular problems such as photokeratitis, snow blindness, cataracts,
pterygium, and various forms of eye cancer.[4] Medical experts often advise the
public on the importance of wearing sunglasses to protect the eyes from UV[4].
In the European Union, a CE mark identifies glasses fulfilling quality
regulations. In the preparation for solar eclipses, health authorities often
warn against looking at the sun through sunglasses alone.
There is no demonstrated correlation between high prices and increased UV
protection. A 1995 study reported that "Expensive brands and polarizing
sunglasses do not guarantee optimal UVA protection." [5] The Australian
Competition and Consumer Commission has also reported that "[c]onsumers cannot
rely on price as an indicator of quality".[6] One survey cited below even found
a $6.95 pair of generic glasses with slightly better protection than Salvatore
Ferragamo shades.[7]
More recently, high-energy visible light (HEV) has been implicated as a cause of
age-related macular degeneration[8][9], and some manufacturers design to block
it. Sunglasses may be especially important for children, as their ocular lenses
are thought to transmit far more HEV light than adults (lenses "yellow" with
age).
Some sunglasses also pass ANSI Z87.1 requirements for basic impact and high
impact protection. These are voluntary standards, so not all sunglasses comply,
nor are manufacturers required to comply. In the basic impact test, a 1 in (2.54
cm) steel ball is dropped on the lens from 50 in (127 cm). In the high velocity
test, a 1/4 in (6.35mm) steel ball is shot at the lens at 150 ft/s (45.72 m/s).
In both tests, no part of the lens can touch the eye.
Standards
There are three sunglass standards.[10]
The Australian Standard is AS 1067. The five sunglass ratings under this
standard are based on the amount of light they absorb, 0 to 4, with “0”
providing some protection from UV radiation and sunglare, and “4” a high level
of protection.
The US standard is ANSI Z80.3-1972. According to the ANSI Z80.3-2001 standard,
the compliable lens should have a UVB (280 to 315nm) transmittance of no more
than one per cent and a UVA (315 to 380nm) transmittance of no more than 0.5
times of the visual light transmittance
The European standard is EN 1836:2005. The four ratings are 0 for insufficient
UV protection, 1 for sufficient UV protection, 2 for good UV protection and 3
for full UV protection.
Water sunglasses
Water sunglasses, also known as surfing sunglasses, surf goggles and water
eyewear consist of eyewear specially adapted to be used in turbulent water, such
as the surf. Features normally available include
a) shatter proof & impact resistant lenses
b) strap or other fixing to keep glasses in place during sporting activities
c) buoyancy to stop them from sinking should they be displaced from the wearer
d) nose cushion
e) vent or other method to eliminate fogging
Many sports utilize these sunglasses including surfing, windsurfing,
kiteboarding, wakeboarding, kayaking, jet skiing, Bodyboarding, and water
skiing.
Construction
Lens
The colour of the lens can vary by style, fashion, and purpose, but for general
use, green, grey, yellow, or brown is recommended to avoid or minimize color
distortion which would be dangerous when, for instance, driving a car. Gray
lenses are considered neutral because they do not enhance contrast or distort
colors. Brown and green lenses cause some minimal color distortion, but have
contrast-enhancing properties. Red lenses are good for medium and lower light
conditions because they are good at enhancing contrast, but cause significant
color distortion. Orange and yellow lenses have the best contrast enhancement at
depth perception but cause color distortion. Yellow lenses are commonly used by
golfers and shooters for its contrast enhancement and depth perception
properties. Blue or purple lenses offer no real benefits and are mainly
cosmetic. With the introduction of office computing, ergonomists can recommend
mildly tinted glasses for display operators to increase contrast.[citation
needed] Clear lenses are used typically to protect the eyes from impact, debris,
dust, or chemicals. Some sunglasses with interchangeable lens have optional
clear lenses to protect the eyes during low light or night time activities.
Debates exist as to whether "blue blocking" or amber tinted lenses may have a
protective effect.[11] Blue blocking sunglasses typically also block some light
of other colors to function well in full sunlight. Some low blue glasses are for
use inside at night to avoid suppression of the sleep promoting hormone
melatonin.[citation needed] They provide enough light so normal evening
activities can continue.
Some models have polarized lenses, made of Polaroid polarized plastic sheet, to
reduce glare caused by light reflected from polarizing surfaces such as water
(see Brewster's angle for how this works) as well as by polarized diffuse sky
radiation (skylight). This can be especially useful when fishing, as the ability
to see beneath the surface of the water is crucial.
A mirrored coating can also be applied to the lens. This mirrored coating
reflects some of the light when it hits the lens before it is transmitted
through the lens making it useful in bright conditions. These mirrored coatings
can be made any color by the manufacturer for styling and fashion purposes. The
color of the mirrored surface is irrelevant to the color of the lens. For
example, a gray lens can have a blue mirror coating, and a brown lens can have a
silver coating. Sunglasses of this type are sometimes called mirrorshades. A
mirror does not get hot in the sunlight and prevents scattering in the lens
bulk.
Sunglass lenses are made from either glass or plastic. Plastic lenses are
typically made from acrylic, polycarbonate, CR-39 or Polyurethane. Glass lenses
have the best optical clarity and scratch resistance, but are heavier than
plastic lenses. They can also shatter or break on impact. Plastic lenses are
lighter but are more prone to scratching. Plastic offers more resistance to
shattering than glass. Polycarbonate plastic lenses are the lightest, and are
also almost shatterproof, making them good for impact protection. CR-39 is the
most common plastic lens, due to their low weight, high scratch resistance, and
low transparency for ultraviolet and infrared radiation.
Any of the above features: color, polarization, gradation, mirroring, and
materials can be combined into the lens for a pair of sunglasses. Gradated
glasses are darker at the top of the lens where the sky is viewed and
transparent at the bottom. Corrective lenses or glasses can be manufactured with
either tinting or darkened to serve as sunglasses. An alternative is to use the
corrective glasses with a secondary lenses such as oversize sunglasses that fit
over the regular glasses, clip-on lens that are placed in front of the glasses,
and flip-up glasses which feature a dark lens that can be flipped up when not in
use. Photochromic lens gradually darken in bright light.
Frames
Frames are generally made from plastic, nylon, a metal or metal alloy. Nylon
frames are usually used in sports because they are light weight and flexible.
They are able to bend slightly and return to their original shape instead of
breaking when pressure is applied to them. This flex can also help the glasses
grip better on the wearer's face. Metal frames are usually more rigid than nylon
frames thus they can be more easily damaged when participating in sporty
activities, but this is not to say that they cannot be used for such activities.
Because metal frames are more rigid, some models have spring loaded hinges to
help them grip the wearer's face better. The end of the ear pieces and the
bridge over the nose can be textured or have a rubber or plastic material to
hold better. The end of the ear pieces are usually curved so that they wrap
around the ear; however, some models have straight ear pieces. Oakley, for
example, has straight ear pieces on all their glasses.
Frames can be made to hold the lenses in several different ways. There are three
common styles: full frame, half frame, and frameless. Full frame glasses have
the frame go all around the lenses. Half frames go around only half the lens,
typically the frames attach to the top of the lenses and on the side near the
top. Frameless glasses have no frame around the lenses and the ear stems are
attached directly to the lenses. There are two styles of frameless glasses:
those that have a piece of frame material connecting the two lenses together,
and those that are a single lens with ear stems on each side.
Some sports-oriented sunglasses have interchangeable lens options. Lenses can be
easily removed and swapped with a different lens, usually a different coloured
lens. The purpose of this is to allow the wearer to easily change lenses when
light conditions or activities change. The reason for this is because the cost
of a set of lenses is less than the cost of a separate pair of glasses and
carrying extra lenses is less bulky than carrying multiple pairs of glasses. It
also allows easy replacement of a set of lenses if they are damaged. The most
common type of sunglasses with interchangeable lenses have a single lens or
shield that covers both eyes. Styles that use two lenses also exist, but are
less common.
Nose Bridge
Nose bridges allow support between the lens and the face. Nose bridges also
prevent pressure marks caused by the weight of the lens or frame on the cheeks.
People with large noses may need a low nose bridge on their sunglasses. People
with medium noses may need a low or medium nose bridge. People with small noses
may need sunglasses with high nose bridges to allow clearance.
Fashion
[edit] Oversized sunglasses
Oversized sunglasses ,which were fashionable in the 1980s, are now often used
for humorous purposes, and look like a pair of sunglasses that is extremely
large for the face. They usually come in bright colors with colored lenses and
can be purchased cheaply.
The singer Elton John would sometimes wear oversized sunglasses on stage in the
mid 1970's as part of his Captain Fantastic stage act.
Over recent years however, moderately oversized sunglasses have become a fashion
trend. There are many variations, such as the 'Onassis', discussed below, and
Dior white sunglasses.
Onassis glasses
Onassis glasses or "Jackie O's" are very large sunglasses worn by women. This
style of sunglasses is said to mimic the kind most famously worn by Jacqueline
Kennedy Onassis in the 1960s. The glasses continue to be popular with women, and
celebrities may use these to hide from paparazzi.
Mirrorshades
Main article: Mirrorshades (fashion)
Mirrorshades are sunglasses with a mirrored coating on the surface. Their
popularity with police officers in the United States has earned them the
nickname "cop shades". The two most popular styles for these are dual lenses set
in metal frames (which are often confused with Aviators), and "Wraparound" (a
single, smooth, semi-circular lens that covers both eyes and much of the same
area of the face covered by protective goggles, combined with a minimal plastic
frame and single piece of plastic serving as a nosepiece). Wraparound sunglasses
are also quite popular in the world of extreme sports.
Aviators are sunglasses with an oversized teardrop-shaped lens and thin metal
frames. This design first appeared in 1936 by Ray-Ban for issue to U.S. military
aviators. Their popularity with pilots, military and law enforcement personnel
in the United States has never wavered. As a fashion statement, models of
aviator sunglasses are often made in mirrored, colored, degregated, and
wrap-around styles. In addition to pilots, Aviator-style sunglasses gained
popularity with young people in the late 1960s and continued to be very popular
with only a brief fall in demand during the 1990s.
Wayfarers
Main article: Ray-Ban Wayfarer
First introduced by Ray-Ban, the Wayfarer design popularized since the 1950s by
Hollywood celebrities such as James Dean is thought to be the bestselling
sunglasses design to date.
Teashades
Teashades' (sometimes also called "John Lennon glasses" or "Ozzy Glasses", after
Ozzy Osbourne') were a type of Psychedelic art wire-rim sunglasses that were
often worn, usually for purely aesthetic reasons, by members of the 1960s drug
counterculture, as well as by opponents of segregation. Rock stars such as Mick
Jagger, John Lennon, Jerry Garcia,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 degregated, 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 rare to find in shops today
however can be found at many costume websites and different countries.
The term has now fallen into disuse, although references can still be found in
literature of the time. Teashades are briefly referenced during a police
training seminar in Hunter S. Thompson's Fear and Loathing in Las Vegas.
'Teashades' also was 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. Ban Mido
(GetBackers) and Basara Nekki (Macross 7) are almost never seen without their
purple-lensed teashades. Former professional wrestler Bret Hart is also known
for wearing teashades at live and televised appearances during his wrestling
career.
Tim Roth also favours teashade sunglasses.
Glacier Glasses
Sometimes called glacier goggles: sunglasses with leather blinders at the sides
that protect the eyes by blocking the sun's rays around the edges of the lenses.
Typically, these have very dark round lenses. Because they provide extra
protection from bright sun and light reflected by snow and ice, they are often
used when mountain climbing, or traveling across glaciers or snowfields.
Faded/ Graduated Lenses
The Faded lenses refer to the fade in which sunlight is blocked from ones face.
For example there will be more protection from sunlight the higher you look on
the lens but the farther one looks down the less protection one gets. The
fashion advantage is that one can wear them inside and not fear tripping over
something and also allowing the user to see. Wearing sunglasses to nightclubs
has become common in recent times, where the faded lens comes in handy. The
Independent (London), has also referred to these style of sunglasses as the
Murphy Lens.[12]
Fashion
Other names for sunglasses
There are also various words referring to eyepieces with darkened lenses:
Glares is a term popular in India if the glass is dark. If it is light then
Coolers
Sun spectacles is a term used by some opticians.
Spekkies is a term used predominantly in southern Australia.
Sun specs (also sunspecs) is the shortened form of the above term.
Sunglass a monocle version.[citation needed]
Sun-shades can also refer to the sun-shading eyepiece-type, although the term is
not exclusive to these. Also in use is the derivative abbreviation, shades.
Dark glasses (also preceded by pair of) - generic term in common usage.
Sunnies is Australian and New Zealand Slang
Specs is a common name for sunglasses in North America.
Smoked spectacles usually refers to the darkened eyepieces worn by blind people.
Solar Shields Usually refers to the models of sunglasses with large lenses.
Stunna shades Used as a slang term in the hyphy movement, usually referring to
sunglasses with oversized lenses.
Shades
Hater blockers
Locs (also maddoggers) is a term for very dark lensed sunglasses.
Bono's This refers to the lead singer in U2 often seen wearing sunglasses
Gecks is Scottish slang for glasses or sunglasses.
Notes and referencesl references-column-count references-column-count-2"
style="-moz-column-count: 2; column-count: 2"> ^ Pliny the Elder, The Natural
History, Book XXXVII, Ch. 16
Ament, Phil (2006-12-04). "Sunglasses History - The Invention of Sunglasses".
The Great Idea Finder. Vaunt Design Group. Retrieved on 2007-06-28.
Sakamoto Y, Sasaki K, Kojima M, Sasaki H, Sakamoto A, Sakai M, Tatami A. "The
effects of protective eyewear on glare and crystalline lens transparency. Dev
Ophthalmol. 2002;35:93-103. PMID 12061282.
a b Cancer Council Australia; Centre for Eye Research Australia.pdf "Position
Statement: Eye Protection"]
Leow YH, Tham SN. "UV-protective sunglasses for UVA irradiation protection." Int
J Dermatol. 1995 Nov;34(11):808-10. PMID 8543419.
Sunglasses and fashion spectacles—April 2003
wcbstv.com - Some Sunglasses Are Cheap In Price Only
Glazer-Hockstein C, Dunaief JL. "Could blue light-blocking lenses decrease the
risk of age-related macular degeneration?" Retina. 2006 Jan;26(1):1-4. PMID
16395131
Margrain TH, Boulton M, Marshall J, Sliney DH. "Do blue light filters confer
protection against age-related macular degeneration?" Prog Retin Eye Res. 2004
Sep;23(5):523-31. PMID 15302349
Clinical and Experimental Optometry
American Academy of Ophthalmology. "Information from Your Eye M.D.: Sunglasses."
November 2003.
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