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Sunglasses or sun glasses (informally called shades or sunnies; more names
Since prehistoric times until the spread of contemporary UV-shielding
One of the earliest surviving depictions of a person wearing sunglasses is of the scientist
Sunglasses or sun glasses (informally called shades or sunnies; more names below
Below may refer to:
*Earth
*Ground (disambiguation)
*Soil
*Floor
*Bottom (disambiguation)
*Less than
*Temperatures below freezing
*Hell or underworld
People with the surname
*Ernst von Below (1863–1955), German World War I general
*Fred Below ( ...
) are a form of protective eyewear
Eye protection is protective gear for the eyes, and sometimes face, designed to reduce the risk of injury. Examples of risks requiring eye protection can include: impact from particles or debris, light or radiation, wind blast, heat, sea s ...
designed primarily to prevent bright sunlight
Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when ...
and high-energy visible light
High-energy visible light (HEV light) is high-frequency, high-energy light in the violet/blue band from 400 to 450 nm in the visible spectrum,
which has a number of biological effects, including those on the eye.
HEV light may be a cause o ...
from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously termed spectacles or glasses
Glasses, also known as eyeglasses or spectacles, are vision eyewear, with lenses (clear or tinted) mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms (known as temples ...
exist, featuring lenses that are colored, polarized or darkened. In the early 20th century, they were also known as sun cheaters (cheaters then being an American
American(s) may refer to:
* American, something of, from, or related to the United States of America, commonly known as the "United States" or "America"
** Americans, citizens and nationals of the United States of America
** American ancestry, pe ...
slang term for glasses).
Since the 1930s, sunglasses have been a popular fashion accessory, especially on the beach
A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc s ...
.
The American Optometric Association
The American Optometric Association (AOA), founded in 1898, represents approximately 37,000 doctors of optometry, optometry students and para-optometric assistants and technicians in the United States.
Overview
The AOA states that:
The American O ...
recommends wearing sunglasses that block ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...
radiation (UV) whenever a person is in the sunlight to protect the eyes from UV and blue light, which can cause several serious eye problems. Their usage is mandatory immediately after some surgical procedures, such as LASIK
LASIK or Lasik (''laser-assisted in situ keratomileusis''), commonly referred to as laser eye surgery or laser vision correction, is a type of refractive surgery for the correction of myopia, hyperopia, and an actual cure for astigmatism (eye), ...
, and recommended for a certain time period in dusty areas, when leaving the house and in front of a TV screen or computer monitor after LASEK
Photorefractive keratectomy (PRK) and laser-assisted sub-epithelial keratectomy (or laser epithelial keratomileusis) (LASEK) are laser eye surgery procedures intended to correct a person's vision, reducing dependency on glasses or contact lense ...
. It is important to note that dark glasses that do not block UV radiation can be more damaging to the eyes than not wearing eye protection at all, since they tend to open the pupil and allow more UV rays into the eye.
History
First precursors
Since prehistoric times until the spread of contemporary UV-shielding spectacle
In general, spectacle refers to an event that is memorable for the appearance it creates. Derived in Middle English from c. 1340 as "specially prepared or arranged display" it was borrowed from Old French ''spectacle'', itself a reflection of t ...
s against snowblindness, Inuit
Inuit (; iu, ᐃᓄᐃᑦ 'the people', singular: Inuk, , dual: Inuuk, ) are a group of culturally similar indigenous peoples inhabiting the Arctic and subarctic regions of Greenland, Labrador, Quebec, Nunavut, the Northwest Territorie ...
made and wore Snow goggles
Snow goggles (Inuktitut: or , syllabics: or ; esu, nigaugek, ) are a type of eyewear traditionally used by the Inuit and the Yupik peoples of the Arctic to prevent snow blindness. The goggles fit tightly against the face so that the only l ...
of flattened walrus or caribou ivory with narrow slits to look through to block almost all of the harmful reflected rays of the sun. In many different forms and with many different materials, the indigenous peoples of North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...
and northern Asia crafted highly efficient equipment to protect their eyes against the damaging effects of strong sunlight in icy circumstances.
Other precursors
It is said that the Roman emperorNero
Nero Claudius Caesar Augustus Germanicus ( ; born Lucius Domitius Ahenobarbus; 15 December AD 37 – 9 June AD 68), was the fifth Roman emperor and final emperor of the Julio-Claudian dynasty, reigning from AD 54 un ...
liked to watch gladiator
A gladiator ( la, gladiator, "swordsman", from , "sword") was an armed combatant who entertained audiences in the Roman Republic and Roman Empire in violent confrontations with other gladiators, wild animals, and condemned criminals. Some gla ...
fights using cut emerald
Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium or sometimes vanadium.Hurlbut, Cornelius S. Jr. and Kammerling, Robert C. (1991) ''Gemology'', John Wiley & Sons, New York, p ...
s. These, however, appear to have worked rather like mirrors.
The first sunglasses, made from flat panes of smoky quartz
Smoky quartz is a brownish grey, translucent variety of quartz that ranges in clarity from almost complete transparency to an almost-opaque brownish-gray or black crystals. The smoky color results from free silicon formed from the silicon dioxide ...
called ''Ai Tai'', meaning ‘dark clouds', which offered no corrective powers but did protect the eyes from glare
Glare (derived from GLAss REinforced laminate ) is a fiber metal laminate (FML) composed of several very thin layers of metal (usually aluminum) interspersed with layers of S-2 glass-fiber ''pre-preg'', bonded together with a matrix such as epo ...
, were used in China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...
in the 12th century or possibly earlier. Documents describe the use of such crystal sunglasses by judges in ancient Chinese court
A court is any person or institution, often as a government institution, with the authority to adjudicate legal disputes between parties and carry out the administration of justice in civil, criminal, and administrative matters in acco ...
s to conceal their facial expressions while questioning witnesses.
In 1459, Nuno Fernandes made a request for a pair of spectacles to protect the eyes while horseriding in the snow against the glare coming from the snow, though no description of any actual spectacles is given.
King Louis XIV
Louis XIV (Louis Dieudonné; 5 September 16381 September 1715), also known as Louis the Great () or the Sun King (), was List of French monarchs, King of France from 14 May 1643 until his death in 1715. His reign of 72 years and 110 days is the Li ...
's court watched the 1706 Solar eclipse through a telescope with a smoky glass filter attached.
By the 18th century tainted mirror-like framed Murano glass
Venetian glass () is glassware made in Venice, typically on the island of Murano near the city. Traditionally it is made with a soda–lime "metal" and is typically elaborately decorated, with various "hot" glass-forming techniques, as well a ...
es had been used as so-called 'gondola glasses' (''vetri da gondola'' and also ''da dama'') by Venician women and children, to shield their eyes from the glare from the water in the canals. The Doge
A doge ( , ; plural dogi or doges) was an elected lord and head of state in several Italian city-states, notably Venice and Genoa, during the medieval and renaissance periods. Such states are referred to as " crowned republics".
Etymology
The ...
and other well-off Venecians such as possibly Goldoni sported in the later 18th century so-called 'goldoni glasses', tainted pairs of spectacles with pieces of cloth as sun guards on the sides of the glasses.
James Ayscough
James Ayscough (born 1720, died 1759) was an English optician and designer and maker of scientific instruments. He was apprenticed to an optician named James Mann from 1743 to 1747. James Ayscough became known for his microscopes. His shop ...
began experimenting with tinted lenses in spectacles in the mid-18th century, around 1752. These were not "sunglasses" as that term is now used; Ayscough believed that blue- or green-tinted glass could correct for specific vision impairments. Protection from the Sun's rays was not a concern for him.
One of the earliest surviving depictions of a person wearing sunglasses is of the scientist Antoine Lavoisier
Antoine-Laurent de Lavoisier ( , ; ; 26 August 17438 May 1794),
CNRS (
CNRS (
Popularly it is claimed that yellow/amber and brown-tinted glasses have been used to alleviate symptoms of
Sunglasses offer protection against excessive exposure to light, including its visible and invisible components.
The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as
. Sehschaden im Alter vorbeugen und mildern. Informationen und Empfehlungen zur altersbedingten Makuladegeneration und zum grauen Star. reventing and Alleviating Vision Damage at Higher Age. Information and Recommendations for Age-Related Macular Degeneration
Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Eine dringende Aufgabe und ihre Lösung. Teil 1: Beschaffenheit des Lichts, innere und äußere Abwehrmechanismen. [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution
/nowiki>]. ''Zeitschrift für praktische Augenheilkunde, 29,'' pp. 111-116.
Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Teil 2: Sehprozess als Risikofaktor, Lichtschutz durch Brillen [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution
/nowiki>]. ''Zeitschrift für praktische Augenheilkunde, 29,'' pp. 197-205. Sunglasses are not sufficient to protect the eyes against permanent harm from looking directly at the Sun, even during a solar eclipse. Special eyewear known as solar viewers are required for direct viewing of the sun. This type of eyewear can filter out UV radiation harmful to the eyes. More recently,
"Information from Your Eye M.D.: Sunglasses."
November 2003. Some manufacturers already design glasses to block blue light; the insurance company
The only way to assess the protection of sunglasses is to have the lenses measured, either by the manufacturer or by a properly equipped
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 
Fashion trends can be another reason for wearing sunglasses, particularly designer sunglasses from high-end fashion brands. Sunglasses of particular shapes may be in vogue as a
. Retrieved 21 September 2009.
website of ''
Retrieved 22 June 2011.
When driving a vehicle, particularly at high speed, dazzling glare caused by a low Sun, or by lights reflecting off snow, puddles, other vehicles, or even the front of the vehicle, can be lethal. Sunglasses can protect against glare when driving. Two criteria must be met: vision must be clear, and the glasses must let sufficient light get to the eyes for the driving conditions. General-purpose sunglasses may be too dark, or otherwise unsuitable for driving.
Like corrective glasses, sunglasses have to meet special requirements when worn for sports. They need shatterproof and impact-resistant lenses; a strap or other fixing is typically used to keep glasses in place during sporting activities, and they have a nose cushion.
For water sports, so-called water sunglasses (also: surf
Seal Swim Goggles.jpg, Swimming goggles
Special protection is required for space travel because the sunlight is far more intense and harmful than on Earth, where it is always filtered through the
EdwinAldrin big.jpg, 1969 on board the
The
polykrypton-C type of lens
which was 'cutting edge' in 1995. Any of the above features, color, polarization, gradation, mirroring, and materials, can be combined into the lens for a pair of sunglasses. Gradient glasses are darker at the top of the lens where the sky is viewed and transparent at the bottom.
Frames are generally made of plastic,
Aviator sunglasses feature oversize teardrop-shaped lenses and a thin metal frame with double or triple bridges.
The design was introduced in 1936 by Bausch & Lomb for issue to U.S. military aviators. As a fashion statement, ''aviator'' sunglasses are often made in mirrored, colored, and wrap-around styles.
The model first gained popularity in the 1940s when Douglas MacArthur was seen sporting a pair at the Pacific Theatre. However, it was in the late 1960s when the frames became widely used with the rise of the hippie counterculture, which preferred large metallic sunglasses. The brand became an icon of the 1970s, worn by Paul McCartney and Freddie Mercury among others, and was also used as prescription eyeglasses. Aviators' association with disco culture led to a decline in their popularity by 1980. The model saw more limited use throughout the 1980s and 1990s, aided by a 1982 product placement deal, featured most notably in ''Top Gun'' and ''Cobra'', with both films causing a 40% rise in 1986. Aviators became popular again around 2000, as the hippie movement experienced a brief revival, and was prominently featured in the MTV show ''Jackass (television series), Jackass''.
Oversized sunglasses, which were fashionable in the 1980s, are now often used for humorous purposes. They usually come in bright colors with colored lenses and can be purchased cheaply.
The singer Elton John sometimes wore oversized sunglasses on stage in the mid-1970s as part of his Captain Fantastic and the Brown Dirt Cowboy, Captain Fantastic act.
Since the late 2000s, moderately oversized sunglasses have become a fashion trend. There are many variations, such as the "Onassis", discussed below, and Dior white sunglasses.
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 them, ostensibly to hide from paparazzi.
Oversized sunglasses, because of their larger frames and lenses, are useful for individuals who are trying to minimize the apparent size or aquiline nose, arch of their nose. Oversized sunglasses also offer more protection from sunburn due to the larger areas of skin they cover, although sunblock should still be used.
"Teashades" (sometimes also called "John Lennon glasses", "Round Metal", 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. Pop icons such as Mick Jagger, Roger Daltrey, John Lennon, Jerry Garcia, Boy George, Liam Gallagher, Suggs (singer), Suggs, Ozzy Osbourne, Duckie (Jon Cryer) in ''Pretty in Pink (film), Pretty in Pink'' and Jodie Foster's character in the film ''Taxi Driver (film), Taxi Driver'' 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, 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 recreational drugs such as marijuana (conjunctival injection) or heroin (pupillary constriction) or just bloodshot eyes.
The Ray-Ban Wayfarer is a (mostly) plastic-framed design for sunglasses produced by the Ray-Ban company. Introduced in 1952, the trapezoidal lenses are wider at the top than the bottom (inspired by the Browline eyeglasses popular at the time), and were famously worn by James Dean, Roy Orbison, Elvis Presley, Bob Marley, The Beatles and other actors and singers. The original frames were black; frames in many different colors were later introduced. There is often a silver piece on the corners as well. Since the early 1980s, makers have also developed variants of the model, most notably the Clubmaster model, introduced in 1982, essentially Browlines made of plastic.
These were mostly popular in the late 1950s and during the 1960s (being linked to the rock-and-roll/blues and Mod cultures), before plastic glasses were displaced by metallic rims popular among the counter-culture. In the late 1970s, the rise of New wave music, New Romanticism and the popularity of The Blues Brothers aside from 50s and 1960s nostalgia and the anti-disco backlash later on brought the model out of near-retirement, becoming the most sold model between 1980 and 1999 aided by a lucrative 1982 product placement deal, which put it on many movies and TV shows such as ''The Breakfast Club'' and ''Moonlighting (TV series), Moonlighting''. 1980s nostalgia and the influence of the hipster subculture and the television series ''Mad Men'' boosted Wayfarers once again after a slump in the 1990s and 2000s, also aided by a 2000 redesign (New Wayfarer), surpassing Aviators since 2012.
Wrap-arounds are a style of sunglasses characterized by being strongly curved, to wrap around the face. They may have a single curved semi-circular lens that covers both eyes and much of the same area of the face covered by protective goggles, usually with a minimal plastic frame and single piece of plastic serving as a nosepiece. Glasses described as wraparound may alternatively have two lenses, but again with a strongly curved frame.
These were first made in the 1960s as variants of the Aviator model, used by Yoko Ono and Clint Eastwood in the ''Dirty Harry'' films. The modern variant surged in the mid-1980s, heavily based on the then-popular Wayfarer, but adapting it to a more futuristic look. As a backlash against 80s fashion occurred in the 1990s, wraparounds became one of the favorite frames of the decade.
Gradient lenses go from a darker shade at the top to a lighter one at the bottom, so there will be more protection from sunlight the higher one looks through the lens, but the lower one looks through the lens, the less protection is offered. An advantage is that one can wear them indoors without fear of tripping over something and also allowing the user to see. Wearing sunglasses to nightclubs has become common in recent times, where the gradient lens comes in handy. Gradient lenses may also be advantageous for activities such as flying airplanes and driving automobiles, as they allow the operator a clear view of the instrument panel, low in his line of sight and usually hidden in shadow, while still reducing glare from the view out the windscreen. The Independent (London), has also referred to these style of sunglasses as the Murphy Lens.
/ref> Double gradient lenses are dark at the top, light in the middle and dark at the bottom. Gradients should not be confused with bifocals and progressive lenses.
Mirrored lenses have a metallic, partially reflective coating on the outer surface combined with a tinted glass lens. Mirrored lenses of different colors can expand the range of fashion styles.
"What Makes a Good Pair of Sunglasses?"
by George W. Waltz; April 1951 ''Popular Science'' article (pp. 141–146) on sunglasses and the method of mass production at that time period.
ISO 12312-1
{{Authority control Sunglasses, American inventions Ancient Roman technology English inventions Eyewear Fashion accessories Ophthalmology Prevention Sun, Glasses
syphilis
Syphilis () is a sexually transmitted infection caused by the bacterium '' Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, a ...
in the 19th and early 20th centuries, because sensitivity to light being one of the symptoms of the disease, although no sources have been found which state prescription of such.
From the later 19th century short references of sunglasses have been found in reports, such as by a Walter Alden in 1866, who wrote of soldiers using during the American Civil War (1861-5) 'shell spectacles' (''verres de cocquille'') to protect against sunlight on long marches, or by the British T. Longmore reporting in ''The Optical Manual'' (1885) of soldiers in Egypt being equipped with tinted glass 'eye protectors'. By 1895 sunglasses were mentioned in advertisements, such as in ''The Sioux City Journal'' (on June 13).
Modern developments
Jean-Marie-Théodore Fieuzal (1836-1888) was the first to argue for UV protection with (yellow) shaded glasses and, by 1899,Rodenstock GmbH
Rodenstock GMBH () is a German manufacturer of ophthalmic lenses and spectacle frames. The company, which was founded by Thuringian Josef Rodenstock in 1877, headquarters are based in Munich. It has a workforce of 4900 people worldwide, and is ...
produced possibly the first sunglasses intended for shielding eyes from UV light and not just glare
Glare (derived from GLAss REinforced laminate ) is a fiber metal laminate (FML) composed of several very thin layers of metal (usually aluminum) interspersed with layers of S-2 glass-fiber ''pre-preg'', bonded together with a matrix such as epo ...
.
In 1913, Crookes lenses were introduced, made from glass containing cerium
Cerium is a chemical element with the symbol Ce and atomic number 58. Cerium is a soft, ductile, and silvery-white metal that tarnishes when exposed to air. Cerium is the second element in the lanthanide series, and while it often shows the +3 ...
, which completely blocked ultraviolet light. In the early 1920s, the use of sunglasses started to become more widespread, especially among movie stars. Inexpensive mass-produced sunglasses made from celluloid
Celluloids are a class of materials produced by mixing nitrocellulose and camphor, often with added dyes and other agents. Once much more common for its use as photographic film before the advent of safer methods, celluloid's common contemporary ...
were first produced by Sam Foster in 1929. Foster found a ready market on the beach
A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc s ...
es of Atlantic City, New Jersey
Atlantic City, often known by its initials A.C., is a coastal resort city in Atlantic County, New Jersey, United States. The city is known for its casinos, boardwalk, and beaches. In 2020, the city had a population of 38,497.
where he began selling sunglasses under the name Foster Grant
Foster Grant, or FosterGrant, is an American brand of eyewear founded by Sam Foster in 1919. The Foster Grant brand is a subsidiary company of FGX International, a consumer goods wholesaler with headquarters in Smithfield, Rhode Island, which h ...
from a Woolworth on the Boardwalk
A boardwalk (alternatively board walk, boarded path, or promenade) is an elevated footpath, walkway, or causeway built with wooden planks that enables pedestrians to cross wet, fragile, or marshy land. They are also in effect a low type of br ...
. By 1938, ''Life
Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from that which does not, and is defined by the capacity for growth, reaction to stimuli, metabolism, energy ...
'' magazine wrote of how sunglasses were a "new fad for wear on city streets ... a favorite affectation of thousands of women all over the U.S." It stated that 20 million sunglasses were sold in the United States in 1937 but estimated that only about 25% of American wearers needed them to protect their eyes. At the same time, sunglasses started to be used as aids for pilots and even produced for the gaining aviation sector, eventually adding to sunglasses as cultural icons and to their popularity. Polarized sunglasses first became available in 1936 when Edwin H. Land
Edwin Herbert Land, ForMemRS, FRPS, Hon.MRI (May 7, 1909 – March 1, 1991) was an Russian-American scientist and inventor, best known as the co-founder of the Polaroid Corporation. He invented inexpensive filters for polarizing light, ...
began experimenting with making lenses with his patented Polaroid
Polaroid may refer to:
* Polaroid Corporation, an American company known for its instant film and cameras
* Polaroid camera, a brand of instant camera formerly produced by Polaroid Corporation
* Polaroid film, instant film, and photographs
* Polar ...
filter. In 1947, the Armorlite Company began producing lenses with CR-39 resin.
At present, Xiamen
Xiamen ( , ; ), also known as Amoy (, from Hokkien pronunciation ), is a sub-provincial city in southeastern Fujian, People's Republic of China, beside the Taiwan Strait. It is divided into six districts: Huli, Siming, Jimei, Tong' ...
, China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...
is the world's largest producer of sunglasses with its port exporting 120 million pairs each year.
Functions
Visual clarity and comfort
Sunglasses can improve visual comfort and visual clarity by protecting the eye fromglare
Glare (derived from GLAss REinforced laminate ) is a fiber metal laminate (FML) composed of several very thin layers of metal (usually aluminum) interspersed with layers of S-2 glass-fiber ''pre-preg'', bonded together with a matrix such as epo ...
.
Various types of disposable sunglasses are dispensed to patients after receiving mydriatic
Mydriasis is the dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of certain types of drugs.
Normally, as ...
eye drops during eye examination
An eye examination is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations pertaining to the eyes. Eye examinations are primarily performed by an optometrist, ...
s.
The lenses of polarized sunglasses
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of th ...
reduce glare reflected at some angles off shiny non-metallic surfaces, such as water. They allow wearers to see into water when only surface glare would otherwise be seen, and eliminate glare from a road surface when driving into the sun.
Protection
Sunglasses offer protection against excessive exposure to light, including its visible and invisible components.
The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as photokeratitis
Photokeratitis or ultraviolet keratitis is a painful eye condition caused by exposure of insufficiently protected eyes to the ultraviolet (UV) rays from either natural (e.g. intense sunlight) or artificial (e.g. the electric arc during welding) ...
(snow blindness), cataract
A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble ...
s, pterygium
Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits.
The term comes from the Greek word ''pterygion'' meaning "wing".
Types
* Popliteal pter ...
, and various forms of eye cancer
Eye neoplasms can affect all parts of the eye, and can be a benign tumor or a malignant tumor (cancer). Eye cancers can be primary (starts within the eye) or metastatic cancer (spread to the eye from another organ). The two most common cancers th ...
. Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV; for adequate protection, experts recommend sunglasses that reflect or filter out 99% or more of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses that meet this requirement are often labeled as "UV400". This is slightly more protection than the widely used standard of the European Union (see below
Below may refer to:
*Earth
*Ground (disambiguation)
*Soil
*Floor
*Bottom (disambiguation)
*Less than
*Temperatures below freezing
*Hell or underworld
People with the surname
*Ernst von Below (1863–1955), German World War I general
*Fred Below ( ...
), which requires that 95% of the radiation up to only 380 nm must be reflected or filtered out.Siegfried Hünig, in consultation with Albert J. Augustin (Oct. 2007. Sehschaden im Alter vorbeugen und mildern. Informationen und Empfehlungen zur altersbedingten Makuladegeneration und zum grauen Star. reventing and Alleviating Vision Damage at Higher Age. Information and Recommendations for Age-Related Macular Degeneration
Karlsruhe
Karlsruhe ( , , ; South Franconian: ''Kallsruh'') is the third-largest city of the German state (''Land'') of Baden-Württemberg after its capital of Stuttgart and Mannheim, and the 22nd-largest city in the nation, with 308,436 inhabitants. ...
'' (retrieved 21 September 2009)Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Eine dringende Aufgabe und ihre Lösung. Teil 1: Beschaffenheit des Lichts, innere und äußere Abwehrmechanismen. [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution
/nowiki>]. ''Zeitschrift für praktische Augenheilkunde, 29,'' pp. 111-116.
Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Teil 2: Sehprozess als Risikofaktor, Lichtschutz durch Brillen [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution
/nowiki>]. ''Zeitschrift für praktische Augenheilkunde, 29,'' pp. 197-205. Sunglasses are not sufficient to protect the eyes against permanent harm from looking directly at the Sun, even during a solar eclipse. Special eyewear known as solar viewers are required for direct viewing of the sun. This type of eyewear can filter out UV radiation harmful to the eyes. More recently,
high-energy visible light
High-energy visible light (HEV light) is high-frequency, high-energy light in the violet/blue band from 400 to 450 nm in the visible spectrum,
which has a number of biological effects, including those on the eye.
HEV light may be a cause o ...
(HEV) has been implicated as a cause of age-related macular degeneration; before, debates had already existed as to whether "blue blocking" or amber tinted lenses may have a protective effect.American Academy of Ophthalmollogy"Information from Your Eye M.D.: Sunglasses."
November 2003. Some manufacturers already design glasses to block blue light; the insurance company
Suva
Suva () is the capital and largest city of Fiji. It is the home of the country's largest metropolitan area and serves as its major port. The city is located on the southeast coast of the island of Viti Levu, in Rewa Province, Central Div ...
, which covers most Swiss
Swiss may refer to:
* the adjectival form of Switzerland
*Swiss people
Places
* Swiss, Missouri
*Swiss, North Carolina
* Swiss, West Virginia
*Swiss, Wisconsin
Other uses
* Swiss-system tournament, in various games and sports
* Swiss Internation ...
employees, asked eye experts around Charlotte Remé ( ETH Zürich) to develop norms for blue blocking, leading to a recommended minimum of 95% of the blue light. Sunglasses are especially important for children, as their ocular lenses are thought to transmit far more HEV light than adults (lenses "yellow" with age).
There has been some speculation that sunglasses actually promote skin cancer
Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body. There are three main types of skin cancers: basal-cell skin cancer (BCC) ...
. This is due to the eyes being tricked into producing less melanocyte
Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea),
the inner ear,
vaginal epithelium, meninges,
bones,
and hear ...
-stimulating hormone
A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...
in the body.
Assessing protection
The only way to assess the protection of sunglasses is to have the lenses measured, either by the manufacturer or by a properly equipped optician
An optician, or ''dispensing optician'', is a technical practitioner who designs, fits and dispenses lenses for the correction of a person's vision. Opticians determine the specifications of various ophthalmic appliances that will give the nec ...
. Several standards for sunglasses (see below
Below may refer to:
*Earth
*Ground (disambiguation)
*Soil
*Floor
*Bottom (disambiguation)
*Less than
*Temperatures below freezing
*Hell or underworld
People with the surname
*Ernst von Below (1863–1955), German World War I general
*Fred Below ( ...
) allow a general classification of the UV protection (but not the blue light protection), and manufacturers often indicate simply that the sunglasses meet the requirements of a specific standard rather than publish the exact figures.
The only "visible" quality test for sunglasses is their fit. The lenses should fit close enough to the face that only very little "stray light Stray light is light in an optical system, which was not intended in the design. The light may be from the intended source, but follow paths other than intended, or it may be from a source other than the intended source. This light will often set a ...
" can reach the eye from their sides, or from above or below, but not so close that the eyelashes smear the lenses. To protect against "stray light" from the sides, the lenses should fit close enough to the temples and/or merge into broad temple arms or leather blinders.
It is not possible to "see" the protection that sunglasses offer. Dark lenses do not automatically filter out more harmful UV radiation
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiatio ...
and blue light than light lenses. Inadequate dark lenses are even more harmful than inadequate light lenses (or wearing no sunglasses at all) because they provoke the pupil to open wider. As a result, more unfiltered radiation enters the eye. Depending on the manufacturing technology, sufficiently protective lenses can block much or little light, resulting in dark or light lenses. The lens color is not a guarantee either. Lenses of various colors can offer sufficient (or insufficient) UV protection. Regarding blue light, the color gives at least a first indication: Blue blocking lenses are commonly yellow or brown, whereas blue or gray lenses cannot offer the necessary blue light protection. However, not every yellow or brown lens blocks sufficient blue light. In rare cases, lenses can filter out too much blue light (i.e., 100%), which affects color vision and can be dangerous in traffic when colored signals are not properly recognized.
High prices cannot guarantee sufficient protection as no correlation between high prices and increased UV protection has been demonstrated. A 1995 study reported that "Expensive brands and polarizing sunglasses do not guarantee optimal UVA protection." The Australian Competition & Consumer Commission
The Australian Competition and Consumer Commission (ACCC) is the chief competition regulator of the Government of Australia, located within the Department of the Treasury. It was established in 1995 with the amalgamation of the Australian Trad ...
has also reported that " nsumers cannot rely on price as an indicator of quality". One survey even found that a $6.95 pair of generic glasses offered slightly better protection than expensive Salvatore Ferragamo
Salvatore Ferragamo (5 June 1898 – 7 August 1960) was an Italian shoe designer and the founder of luxury goods high-end retailer Salvatore Ferragamo S.p.A. An innovative shoe designer, Salvatore Ferragamo established a reputation in the 1930s. ...
shades.
Further functions
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
Eye contact occurs when two people look at each other's eyes at the same time. In humans, eye contact is a form of nonverbal communication and can have a large influence on social behavior. Coined in the early to mid-1960s, the term came from ...
impossible, which can be intimidating to those not wearing sunglasses; the avoided eye contact can also demonstrate the wearer's detachment, which is considered desirable (or " cool") in some circles. Eye contact can be avoided even more effectively by using mirrored sunglasses
Mirrored sunglasses are sunglasses with a reflective optical coating (called a mirror coating or flash coating) on the outside of the lenses to make them appear like small mirrors. The lenses typically give the wearer's vision a brown or grey ti ...
. 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
Nonverbal communication (NVC) is the transmission of messages or signals through a nonverbal platform such as eye contact, facial expressions, gestures, posture, and body language. It includes the use of social cues, kinesics, distance ( pr ...
; this is useful in poker
Poker is a family of comparing card games in which players wager over which hand is best according to that specific game's rules. It is played worldwide, however in some places the rules may vary. While the earliest known form of the game wa ...
, and many professional poker players wear heavily tinted glasses indoors while playing, so that it is more difficult for opponents to read tells which involve eye movement and thus gain an advantage.
Fashion trends can be another reason for wearing sunglasses, particularly designer sunglasses from high-end fashion brands. Sunglasses of particular shapes may be in vogue as a fashion accessory
In fashion, an accessory is an item used to contribute, in a secondary manner, to an individual's outfit. Accessories are often chosen to complete an outfit and complement the wearer's look. They have the capacity to further express an individua ...
. The relevance of sunglasses within the fashion industry has included prominent fashion editors' reviews of annual trends in sunglasses as well as runway fashion shows featuring sunglasses as a primary or secondary component of a look. Fashion trends can also draw on the "cool" image of sunglasses and association with a particular lifestyle, especially the close connection between sunglasses and beach life. In some cases, this connection serves as the core concept behind an entire brand.
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, chronic dark circles or crow's feet, recent physical abuse (such as a black eye
A periorbital hematoma, commonly called a black eye or a shiner (associated with boxing or stick sports such as hockey), is bruising around the eye commonly due to an injury to the face rather than to the eye. The name refers to the dark-colo ...
), exophthalmos
Exophthalmos (also called exophthalmus, exophthalmia, proptosis, or exorbitism) is a bulging of the eye anteriorly out of the orbit. Exophthalmos can be either bilateral (as is often seen in Graves' disease) or unilateral (as is often seen in ...
(bulging eyes), a cataract
A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble ...
, or eyes which jerk uncontrollably (nystagmus
Nystagmus is a condition of involuntary (or voluntary, in some cases) eye movement. Infants can be born with it but more commonly acquire it in infancy or later in life. In many cases it may result in reduced or limited vision. Due to the invol ...
).
Lawbreakers have been known to wear sunglasses during or after committing a crime as an aid to hiding their identities.
Standards
The international standard for sunglasses is ISO 12312, which was published in 2013. Part 1 specifies the physical and optical characteristics of glasses, including a range of UV protection levels. Part 2 specifies the test methods used to validate conformance with Part 1.''no author'' (2004). Requirements of European Directives and Standards Relating to Sunglasses.. Retrieved 21 September 2009.
Australia
Australia introduced the world's first national standards for sunglasses in 1971. They were updated and expanded in 1990 to ''AS 1067.1-1990 Sunglasses and fashion spectacles'' (incl. Part 1 Safety Requirements and Part 2 Performance Requirements), and replaced in 2003 by AS/NZS 1067:2003 Sunglasses and fashion spectacles. This aligned the Australian standard to the European standard opening the European market to Australian-made sunglasses.''no author'' (2002). Public eye looks over new standard for sunglasses (2002-01-20).website of ''
Standards Australia
Standards Australia is a standards organisation established in 1922 and is recognised through a Memorandum of Understanding (MoU) with the Australian government as the primary non-government standards development body in Australia. It is a com ...
''. Retrieved 21 September 2009. The Australian Standard AS-NZS 1067 defines standards for sunglasses with respect both to UVA (wavelengths between 315 nm and 400 nm) and UVB transmittance. The five ratings for transmittance (filter) under this standard are based on the amount of absorbed light, 0 to 4, with "0" providing some protection from UV radiation and sunglare, and "4" indicating a high level of protection, but not to be worn when driving.
Europe
The European standard EN 1836:2005 has four transmittance ratings: "0" for insufficient UV protection, "2" for sufficient UHV protection, "6" for good UHV protection and "7" for "full" UHVV protection, meaning that no more than 5% of the 380 nm rays are transmitted. Products which fulfill the standard receive aCE mark
On commercial products, the letters CE (as the logo ) mean that the manufacturer or importer affirms the good's conformity with European health, safety, and environmental protection standards. It is not a quality indicator or a certificat ...
. There is no European rating for transmittance protection for radiation of up to 400 nm ("UV400"), as required in other countries (incl. the United States) and recommended by experts. The current European standard, EN 1836:2005, was preceded by the older standards EN 166:1995 (Personal eye protection – Specifications), EN167: 1995 (Personal eye protection – Optical test methods), and EN168: 1995 (Personal eye protection – Non-optical test methods), which in 2002 were republished as a revised standard under the name of EN 1836:1997 (which included two amendments). In addition to filtering, the standard also lists requirements for minimum robustness, labeling, materials (non-toxic for skin contact and not combustible) and lack of protrusions (to avoid harm when wearing them). Categories for the European standard, which are required to be marked on the frame:
* Category 0 – 80%-100% transmission – for fashion, indoor use, or cloudy days
* Category 1 – 43%-80% transmission – low sun exposure
* Category 2 – 18%-43% transmission – medium sun exposure
* Category 3 – 8%-18% transmission – strong brightness, light reflected of water or snow
* Category 4 – 3%-8% transmission – intense sunshine for high mountains, glaciers; not for use when driving or on the road.
United States
Sunglasses sold in the United States are regulated by theFood and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...
and are required to conform to safety standards. The U.S. standard is ANSI
The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organi ...
Z80.3-2001, which includes three transmittance categories. According to this standard, the lens should have a UVB (280 to 315 nm) transmittance of no more than one per cent and a UVA (315 to 380 nm) transmittance of no more than 0.3 times the visual light transmittance. The ANSI Z87.1-2003 standard includes requirements for basic impact and high impact protection. In the basic impact test, a 1 in (2.54 cm) steel ball is dropped on the lens from a height of 50 in (127 cm). In the high velocity test, a 1/4 in (6.35 mm) steel ball is shot at the lens at 150 ft/s (45.72 m/s). To pass both tests, no part of the lens may touch the eye.''MB Optics Safety'' (2006). The ANSI Z87.1-2003 standard.Retrieved 22 June 2011.
Special-use
Land vehicle driving
When driving a vehicle, particularly at high speed, dazzling glare caused by a low Sun, or by lights reflecting off snow, puddles, other vehicles, or even the front of the vehicle, can be lethal. Sunglasses can protect against glare when driving. Two criteria must be met: vision must be clear, and the glasses must let sufficient light get to the eyes for the driving conditions. General-purpose sunglasses may be too dark, or otherwise unsuitable for driving.
The Automobile Association
AA Limited, trading as The AA (formerly The Automobile Association), is a British motoring association.
Founded in 1905, it provides vehicle insurance, driving lessons, breakdown cover, loans, motoring advice, road maps and other services. T ...
and the Federation of Manufacturing Opticians have produced guidance for selection of sunglasses for driving. Variable tint or photochromic lenses increase their optical density when exposed to UV light, reverting to their clear state when the UV brightness decreases. Car windscreens filter out UV light, slowing and limiting the reaction of the lenses and making them unsuitable for driving as they could become too dark or too light for the conditions. Some manufacturers produce special photochromic lenses that adapt to the varying light conditions when driving.
Lenses of fixed tint are graded according to the optical density of the tint; in the UK sunglasses must be labelled and show the filter category number. Lenses with light transmission less than 75% are unsuitable for night driving, and lenses with light transmission less than 8% (category 4) are unsuitable for driving at any time; they should by UK law be labelled 'Not suitable for driving and road use'. Yellow tinted lenses are also not recommended for night use. Due to the light levels within the car, filter category 2 lenses which transmit between 18% and 43% of light are recommended for daytime driving. Polarised lenses normally have a fixed tint, and can reduce reflected glare more than non-polarised lenses of the same density, particularly on wet roads.
Graduated lenses, with the bottom part lighter than the top, can make it easier to see the controls within the car. All sunglasses should be marked as meeting the standard for the region where sold. An anti-reflection coating is recommended, and a hard coating to protect the lenses from scratches. Sunglasses with deep side arms can block side, or peripheral, vision and are not recommended for driving.
Even though some of these glasses are proven good enough for driving at night, it is strongly recommended not to do so, due to the changes in a wide variety of light intensities, especially while using yellow tinted protection glasses. The main purpose of these glasses are to protect the wearer from dust and smog particles entering into the eyes while driving at high speeds.
Aircraft piloting
Many of the criteria for sunglasses worn when piloting an aircraft are similar to those for land vehicles. Protection against UV radiation is more important, as its intensity increases with altitude. Polarised glasses are undesirable as aircraft windscreens are often polarised, intentionally or unintentionally, showingMoiré pattern
In mathematics, physics, and art, moiré patterns ( , , ) or moiré fringes are large-scale interference patterns that can be produced when an opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré ...
s on looking through the windscreen; and some LCDs used by instruments emit polarised light, and can dim or disappear when the pilot turns to look at them.
Sports
Like corrective glasses, sunglasses have to meet special requirements when worn for sports. They need shatterproof and impact-resistant lenses; a strap or other fixing is typically used to keep glasses in place during sporting activities, and they have a nose cushion.
For water sports, so-called water sunglasses (also: surf goggles
Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and ...
or water eyewear) are specially adapted for use in turbulent water, such as the surf or whitewater
Whitewater forms in a rapid context, in particular, when a river's gradient changes enough to generate so much turbulence that air is trapped within the water. This forms an unstable current that froths, making the water appear opaque and ...
. In addition to the features for sports glasses, water sunglasses can have increased buoyancy
Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the ...
to stop them from sinking should they come off, and they can have a vent or other method to eliminate fogging. These sunglasses are used in water sports such as surfing
Surfing is a surface water sport in which an individual, a surfer (or two in tandem surfing), uses a board to ride on the forward section, or face, of a moving wave of water, which usually carries the surfer towards the shore. Waves suitable ...
, windsurfing
Windsurfing is a wind propelled water sport that is a combination of sailing and surfing. It is also referred to as "sailboarding" and "boardsailing", and emerged in the late 1960s from the aerospace and surf culture of California. Windsurfing ga ...
, kiteboarding
Kiteboarding or kitesurfing is a sport that involves using wind power with a large power kite to pull a rider across a water, land, or snow surface. It combines aspects of paragliding, surfing, windsurfing, skateboarding, snowboarding, and wak ...
, wakeboarding
Wakeboarding is a water sport in which the rider, standing on a wakeboard (a board with foot bindings), is towed behind a motorboat across its wake and especially up off the crest in order to perform aerial maneuvers. A hallmark of wakeboardin ...
, kayaking
Kayaking is the use of a kayak for moving over water. It is distinguished from canoeing by the sitting position of the paddler and the number of blades on the paddle. A kayak is a low-to-the-water, canoe-like boat in which the paddler sits faci ...
, jet skiing
A personal watercraft (PWC), also called water scooter or jet ski, is a recreational watercraft that a rider sits or stands on, not within, as in a boat. PWCs have two style categories, first and most popular being a runabout or "sit down" whe ...
, bodyboarding
Bodyboarding is a water sport in which the surfer rides a bodyboard on the crest, face, and curl of a wave which is carrying the surfer towards the shore. Bodyboarding is also referred to as ''Boogieboarding'' due to the invention of the "Boogie ...
, and water skiing
Water skiing (also waterskiing or water-skiing) is a surface water sport in which an individual is pulled behind a boat or a cable ski installation over a body of water, skimming the surface on two skis or one ski. The sport requires suffic ...
.
Mountain climbing or traveling across glaciers or snowfields requires above-average eye protection, because sunlight (including ultraviolet radiation) is more intense in higher altitudes, and snow and ice reflect additional light. Popular glasses for this use are a type called glacier glasses or glacier goggles
Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and ...
. They typically have very dark round lenses and leather blinders at the sides, which protect the eyes by blocking the Sun's rays around the edges of the lenses.
Special shaded visors were once allowed in American football
American football (referred to simply as football in the United States and Canada), also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end. The offense, the team wi ...
; Jim McMahon
James Robert McMahon Jr. (born August 21, 1959) is a former American football quarterback who played in the National Football League (NFL) for 15 seasons, most notably with the Chicago Bears. McMahon played college football at BYU, where he was ...
, quarterback for the Chicago Bears
The Chicago Bears are a professional American football team based in Chicago. The Bears compete in the National Football League (NFL) as a member club of the league's National Football Conference (NFC) North division. The Bears have won nine ...
and San Diego Chargers
The San Diego Chargers were a professional American football team that played in San Diego from 1961 until the end of the 2016 season, before relocating to Los Angeles, where the franchise had played its inaugural 1960 season. The team is now ...
, famously used a sun visor during his professional football career due to a childhood eye injury and almost always wears dark sunglasses when not wearing a football helmet
The football helmet is a piece of protective equipment used mainly in gridiron football, although a structural variation has occasional use in Australian rules football. It consists of a hard plastic shell with thick padding on the inside, a ...
. Darkened visors now require a doctor's prescription at most levels of the game, mainly because concussion protocol requires officials to look a player in the eye, something made difficult by tinted visors.
Space
Special protection is required for space travel because the sunlight is far more intense and harmful than on Earth, where it is always filtered through the atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A ...
. Sun protection is needed against much higher UV radiation and even against harmful infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from ...
radiation, both within and outside the spacecraft. Within the spacecraft, astronauts wear sunglasses with darker lenses and a thin protective gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile ...
coating. During space walk
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA inc ...
s, the visor of the astronauts' helmets, which also has a thin gold coating for extra protection, functions as strong sunglasses.''no author'' (''no date''). Spinoff 2002. Space-Age Shades. ''Scientific and Technical Information (STI)'' on theNASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeedin ...
website (retrieved on 21 September 2009) The frames of sunglasses and corrective glasses used in space must meet special requirements. They must be flexible and durable, and must fit firmly in zero-gravity. Reliable fit is particularly important when wearing corrective glasses underneath tight helmets and in space suits: once inside the spacesuit, slipped glasses cannot be touched to push them back into place, sometimes for up to ten hours. Frames and glasses must be designed so that small pieces of the glasses such as screws and glass particles cannot become dislodged, then float and be inhaled. 90% of astronauts wear glasses in space, even if they do not require corrective glasses on Earth, because zero-gravity and pressure changes temporarily affect their vision.
The first sunglasses used in a Moon landing were the original pilot sunglasses produced by American Optical. In 1969 they were used aboard the ''Eagle'', the Lunar Module
The Apollo Lunar Module (LM ), originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed ...
of Apollo 11
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, ...
, the first crewed mission to land on the Moon. NASA research primarily by scientists James B. Stephens and Charles G. Miller at the Jet Propulsion Laboratory
The Jet Propulsion Laboratory (JPL) is a Federally funded research and development centers, federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, La Cañada Flintridge, California ...
(JPL) resulted in special lenses that protected against the light in space and during laser and welding work. The lenses used colored dyes and small particles of zinc oxide
Zinc oxide is an inorganic compound with the formula . It is a white powder that is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement ...
, which absorbs ultraviolet light and is also used in sunscreen
Sunscreen, also known as sunblock or sun cream, is a photoprotective topical product for the skin that mainly absorbs, or to a much lesser extent reflects, some of the sun's ultraviolet (UV) radiation and thus helps protect against sunbur ...
lotions. The research was later broadened to further terrestrial applications, ''e.g.'', deserts, mountains, and fluorescent-lighted offices, and the technology was commercially marketed by a U.S. company. Since 2002 NASA uses the frame of the designer model ''Titan Minimal Art'' of the Austrian company Silhouette
A silhouette ( , ) is the image of a person, animal, object or scene represented as a solid shape of a single colour, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the silhou ...
, combined with specially dark lenses developed jointly by the company and "the" NASA optometrist
Optometry is a specialized health care profession that involves examining the eyes and related structures for defects or abnormalities. Optometrists are health care professionals who typically provide comprehensive primary eye care.
In the Un ...
Keith Manuel. The frame is very light at 1.8 grams, and does not have screws or hinges that could detach.
Eagle
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, j ...
: Buzz Aldrin
Buzz Aldrin (; born Edwin Eugene Aldrin Jr.; January 20, 1930) is an American former astronaut, engineer and fighter pilot. He made three spacewalks as pilot of the 1966 Gemini 12 mission. As the Lunar Module ''Eagle'' pilot on the 1969 A ...
stows his sunglasses before the Moon landing
Aldrin Apollo 11 head.jpg, 1969: Helmet visor protecting Aldrin
Aldrin is an organochlorine insecticide that was widely used until the 1990s, when it was banned in most countries. Aldrin is a member of the so-called "classic organochlorines" (COC) group of pesticides. COCs enjoyed a very sharp rise in popular ...
's eyes on the Moon
Construction
Lens
The color
Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associ ...
of the lens can vary depending on style, fashion, and purpose, but for general use, red, grey, green, or brown are recommended to avoid or minimize color distortion, which could affect safety when, for instance, driving a car or a school bus.
* Gray and green lenses are considered neutral because they maintain true colors.
* Brown lenses cause some color distortion, but also increase contrast.
* Turquoise lenses are good for medium and high light conditions, because they are good at enhancing contrast, but do not cause significant color distortion.
* Yellow is "optimum for object definition, but creates a harsh visible light"; amber "allegedly makes distant objects appear more distinct, especially in snow or haze. These lenses are popular with skiers, hunters, boaters and pilots".
* Blue or purple lenses are popular with shooters as they increase the contrast of orange targets against green foliage or grass backdrops.
With the introduction of office computing, ergonomists may recommend mildly tinted glasses for use by display operators, in order to increase contrast.
While some blue blocking sunglasses (see above) are produced as regular sunglasses for exposure to bright sunlight, others—especially for macular degeneration
Macular degeneration, also known as age-related macular degeneration (AMD or ARMD), is a medical condition which may result in blurred or no vision in the center of the visual field. Early on there are often no symptoms. Over time, however, so ...
patients—do not block light or other colors in order to function well in regular daylight and even dim sunlight. The latter allow the passage of enough light so normal evening activities can continue, while blocking the light that prevents production of the hormone
A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...
melatonin
Melatonin is a natural product found in plants and animals. It is primarily known in animals as a hormone released by the pineal gland in the brain at night, and has long been associated with control of the sleep–wake cycle.
In vertebrat ...
. Blue-blocking tinted glasses, i.e. amber or yellow, are sometimes recommended to treat insomnia; they are worn in artificial lighting after dark, to reestablish the circadian rhythm
A circadian rhythm (), or circadian cycle, is a natural, internal process that regulates the sleep–wake cycle and repeats roughly every 24 hours. It can refer to any process that originates within an organism (i.e., endogenous) and responds to ...
and treat delayed sleep phase disorder
Delayed sleep phase disorder (DSPD), more often known as delayed sleep phase syndrome and also as delayed sleep–wake phase disorder, is a delaying of a person's circadian rhythm (biological clock) compared to those of societal norms. The diso ...
.
Some models have polarized lenses, made of Polaroid
Polaroid may refer to:
* Polaroid Corporation, an American company known for its instant film and cameras
* Polaroid camera, a brand of instant camera formerly produced by Polaroid Corporation
* Polaroid film, instant film, and photographs
* Polar ...
polarized plastic sheeting, to reduce glare caused by light reflected from non-metallic surfaces such as water (see Brewster's angle
Brewster's angle (also known as the polarization angle) is an angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with ''no reflection''. When ''unpolarized'' light ...
for how this works) as well as by polarized diffuse sky radiation
Diffuse sky radiation is solar radiation reaching the Earth's surface after having been scattered from the direct solar beam by molecules or particulates in the atmosphere. It is also called sky radiation, the determinative process for ch ...
(skylight). This can be especially useful to see beneath the surface of the water when fishing.
A mirror
A mirror or looking glass is an object that reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the im ...
ed coating can be applied to the lens. This mirrored coating deflects some of the light when it hits the lens so that it is not transmitted through the lens, making it useful in bright conditions; however, it does not necessarily reflect UV radiation as well. 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
''Mirrorshades: The Cyberpunk Anthology'' (1986) is a cyberpunk short story collection, edited by American writer Bruce Sterling.
Contents
* "The Gernsback Continuum" by William Gibson
* "Snake-Eyes" by Tom Maddox
* "Rock On" by Pat Cadigan
* "T ...
. A mirror coating does not get hot in sunlight and it prevents scattering of rays in the lens bulk.
Sunglass lenses are made of either glass
Glass is a non- crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenchin ...
, plastic
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adapta ...
, or SR-91. Plastic lenses are typically made from acrylic
Acrylic may refer to:
Chemicals and materials
* Acrylic acid, the simplest acrylic compound
* Acrylate polymer, a group of polymers (plastics) noted for transparency and elasticity
* Acrylic resin, a group of related thermoplastic or thermosett ...
, polycarbonate
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily work ...
, CR-39 or polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from ...
. 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 and shatter-resistant, but are more prone to scratching. 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 low weight, high scratch resistance, and low transparency for ultraviolet and infrared radiation. SR-91 is a proprietary material that was introduced by Kaenon Polarized in 2001. Kaenon's lens formulation was the first non-polycarbonate material to pass the high-mass impact ANSI Z.87.1 testing. Additionally, it was the first to combine this passing score with the highest marks for lens clarity. Jerry Garcia's sunglasses had polykrypton-C type of lens
which was 'cutting edge' in 1995. Any of the above features, color, polarization, gradation, mirroring, and materials, can be combined into the lens for a pair of sunglasses. Gradient glasses are darker at the top of the lens where the sky is viewed and transparent at the bottom.
Corrective lens
A corrective lens is a lens (i.e. a transmissive optical device) that is typically worn in front of the eye to improve daily vision. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. G ...
es or glasses
Glasses, also known as eyeglasses or spectacles, are vision eyewear, with lenses (clear or tinted) mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms (known as temples ...
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 (see below). Photochromic lens
A photochromic lens is an optical lens that darkens on exposure to light of sufficiently high frequency, most commonly ultraviolet (UV) radiation. In the absence of activating light, the lenses return to their clear state. Photochromic lenses may ...
es gradually darken when exposed to ultraviolet light.
Frames
Frames are generally made of plastic, nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic.
Nylon is a silk-like thermoplastic, generally made from pet ...
, a metal
A metal (from ancient Greek, Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, e ...
or a metal alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, ...
. Nylon frames are usually used in sports because they are lightweight 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 the wearer participates in sport 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
Spring(s) may refer to:
Common uses
* Spring (season), a season of the year
* Spring (device), a mechanical device that stores energy
* Spring (hydrology), a natural source of water
* Spring (mathematics), a geometric surface in the shape of a h ...
loaded hinges to help them grip the wearer's face better. The end of the resting hook and the bridge over the nose can be textured or have rubber
Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
or plastic material to improve hold. The ends of the resting hook are usually curved so that they wrap around the ear; however, some models have straight resting hooks. Oakley, for example, has straight resting hooks on all their glasses, preferring to call them "earstems".
In recent years, manufacturers have started to use various types of woods to make frames for sunglasses. Materials such as bamboo
Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, ...
, ebony
Ebony is a dense black/brown hardwood, coming from several species in the genus '' Diospyros'', which also contains the persimmons. Unlike most woods, ebony is dense enough to sink in water. It is finely textured and has a mirror finish when ...
, rosewood
Rosewood refers to any of a number of richly hued timbers, often brownish with darker veining, but found in many different hues.
True rosewoods
All genuine rosewoods belong to the genus ''Dalbergia''. The pre-eminent rosewood appreciated ...
, pear wood, walnut and zebrawood, are used making them non-toxic and nearly allergy free. The construction of a wooden frame involves laser-cutting from planks of wood. Already cut and ground to a uniform size, a buffing wheel is used to sand and buff every piece separately before they are assembled. The laser-cutouts of wood are then glued together by hand (mostly), layer on layer, to produce wooden frames. Some brands have experimented with recycled wood from objects like skateboard
A skateboard is a type of sports equipment used for skateboarding. They are usually made of a specially designed 7-8 ply maple plywood deck and polyurethane wheels attached to the underside by a pair of skateboarding trucks.
The skateboarder ...
s, whiskey barrels and baseball bat
A baseball bat is a smooth wooden or metal club used in the sport of baseball to hit the ball after it is thrown by the pitcher. By regulation it may be no more than in diameter at the thickest part and no more than in length. Although histor ...
s. Shwood, for example have experimented with these materials, they have even used recycled newspaper to manufacture frames.
Their final look can vary according to the color, type and finishing. With wooden sunglasses, various shades of brown, beige, burgundy or black are most common. Wooden sunglasses come in various designs and shapes. However, these sunglasses are usually more expensive than the conventional plastic, acetate or metal frames and require more care. They have been famously worn by the likes of Beyoncé
Beyoncé Giselle Knowles-Carter ( ; born September 4, 1981) is an American singer, songwriter, and actress. Beyoncé's boundary-pushing artistry and vocals have made her the most influential female musician of the 21st century, according to ...
, Snoop Dogg
Calvin Cordozar Broadus Jr. (born October 20, 1971), known professionally as Snoop Dogg (previously Snoop Doggy Dogg and briefly Snoop Lion), is an American rapper. His fame dates back to 1992 when he featured on Dr. Dre's debut solo single, " ...
and Machine Gun Kelly
George Kelly Barnes (July 18, 1895 – July 18, 1954), better known by his pseudonym "Machine Gun Kelly", was an American gangster from Memphis, Tennessee, active during the Prohibition era. His nickname came from his favorite weapon, a Thom ...
.
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, and those that are a single lens with ear stems on each side.
Some sports-optimized sunglasses have interchangeable lens options. Lenses can be easily removed and swapped for a different lens, usually of a different color. The purpose is to allow the wearer to easily change lenses when light conditions or activities change. The reasons are that 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 has a single lens or shield that covers both eyes. Styles that use two lenses also exist, but are less common.
Nose bridge
Nose bridges provide support between the lens and the face. They 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 (alphabetically)
The following types are not all mutually exclusive; glasses may be in Aviator style with mirrored lenses, for example.Aviator
Aviator sunglasses feature oversize teardrop-shaped lenses and a thin metal frame with double or triple bridges.
The design was introduced in 1936 by Bausch & Lomb for issue to U.S. military aviators. As a fashion statement, ''aviator'' sunglasses are often made in mirrored, colored, and wrap-around styles.
The model first gained popularity in the 1940s when Douglas MacArthur was seen sporting a pair at the Pacific Theatre. However, it was in the late 1960s when the frames became widely used with the rise of the hippie counterculture, which preferred large metallic sunglasses. The brand became an icon of the 1970s, worn by Paul McCartney and Freddie Mercury among others, and was also used as prescription eyeglasses. Aviators' association with disco culture led to a decline in their popularity by 1980. The model saw more limited use throughout the 1980s and 1990s, aided by a 1982 product placement deal, featured most notably in ''Top Gun'' and ''Cobra'', with both films causing a 40% rise in 1986. Aviators became popular again around 2000, as the hippie movement experienced a brief revival, and was prominently featured in the MTV show ''Jackass (television series), Jackass''.
Browline
Based on the eyeglass design of the same name, browline glasses have hard plastic or horn-rimmed glasses, horn-rimmed arms and upper portions joined to a wire lower frame. A traditional, conservative style based on mid-20th century design, browlines were adapted into sunglasses form in the 1980s and rapidly became one of the most popular styles; it has ebbed and sprung in popularity in the decades that have followed.Oversized
Oversized sunglasses, which were fashionable in the 1980s, are now often used for humorous purposes. They usually come in bright colors with colored lenses and can be purchased cheaply.
The singer Elton John sometimes wore oversized sunglasses on stage in the mid-1970s as part of his Captain Fantastic and the Brown Dirt Cowboy, Captain Fantastic act.
Since the late 2000s, moderately oversized sunglasses have become a fashion trend. There are many variations, such as the "Onassis", discussed below, and Dior white sunglasses.
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 them, ostensibly to hide from paparazzi.
Oversized sunglasses, because of their larger frames and lenses, are useful for individuals who are trying to minimize the apparent size or aquiline nose, arch of their nose. Oversized sunglasses also offer more protection from sunburn due to the larger areas of skin they cover, although sunblock should still be used.
Shutter shades
Shutter shades were invented in the late 1940s, became a fad in the early 1980s and have experienced a revival in the early-to-mid 2010s. Instead of tinted lenses, they decrease sun exposure by means of a set of parallel, horizontal shutters (like a small window shutter). Analogous to Snow goggles, Inuit goggles (see #Precursors, above), the principle is not to filter light, but to decrease the amount of sun rays falling into the wearer's eyes. To provide UV protection, shutter shades sometimes use lenses in addition to the shutters; if not, they provide very insufficient protection against ultraviolet radiation and blue light.Teashades
"Teashades" (sometimes also called "John Lennon glasses", "Round Metal", 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. Pop icons such as Mick Jagger, Roger Daltrey, John Lennon, Jerry Garcia, Boy George, Liam Gallagher, Suggs (singer), Suggs, Ozzy Osbourne, Duckie (Jon Cryer) in ''Pretty in Pink (film), Pretty in Pink'' and Jodie Foster's character in the film ''Taxi Driver (film), Taxi Driver'' 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, 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 recreational drugs such as marijuana (conjunctival injection) or heroin (pupillary constriction) or just bloodshot eyes.
Wayfarer
The Ray-Ban Wayfarer is a (mostly) plastic-framed design for sunglasses produced by the Ray-Ban company. Introduced in 1952, the trapezoidal lenses are wider at the top than the bottom (inspired by the Browline eyeglasses popular at the time), and were famously worn by James Dean, Roy Orbison, Elvis Presley, Bob Marley, The Beatles and other actors and singers. The original frames were black; frames in many different colors were later introduced. There is often a silver piece on the corners as well. Since the early 1980s, makers have also developed variants of the model, most notably the Clubmaster model, introduced in 1982, essentially Browlines made of plastic.
These were mostly popular in the late 1950s and during the 1960s (being linked to the rock-and-roll/blues and Mod cultures), before plastic glasses were displaced by metallic rims popular among the counter-culture. In the late 1970s, the rise of New wave music, New Romanticism and the popularity of The Blues Brothers aside from 50s and 1960s nostalgia and the anti-disco backlash later on brought the model out of near-retirement, becoming the most sold model between 1980 and 1999 aided by a lucrative 1982 product placement deal, which put it on many movies and TV shows such as ''The Breakfast Club'' and ''Moonlighting (TV series), Moonlighting''. 1980s nostalgia and the influence of the hipster subculture and the television series ''Mad Men'' boosted Wayfarers once again after a slump in the 1990s and 2000s, also aided by a 2000 redesign (New Wayfarer), surpassing Aviators since 2012.
Wrap-around
Wrap-arounds are a style of sunglasses characterized by being strongly curved, to wrap around the face. They may have a single curved semi-circular lens that covers both eyes and much of the same area of the face covered by protective goggles, usually with a minimal plastic frame and single piece of plastic serving as a nosepiece. Glasses described as wraparound may alternatively have two lenses, but again with a strongly curved frame.
These were first made in the 1960s as variants of the Aviator model, used by Yoko Ono and Clint Eastwood in the ''Dirty Harry'' films. The modern variant surged in the mid-1980s, heavily based on the then-popular Wayfarer, but adapting it to a more futuristic look. As a backlash against 80s fashion occurred in the 1990s, wraparounds became one of the favorite frames of the decade.
Variants
Clip-on
Clip-on glasses are a form of tinted glasses that can be clipped on to eyeglasses for protection from the sun. An alternative are #Flip-up sunglasses, flip-up glasses.Gradient lenses
Gradient lenses go from a darker shade at the top to a lighter one at the bottom, so there will be more protection from sunlight the higher one looks through the lens, but the lower one looks through the lens, the less protection is offered. An advantage is that one can wear them indoors without fear of tripping over something and also allowing the user to see. Wearing sunglasses to nightclubs has become common in recent times, where the gradient lens comes in handy. Gradient lenses may also be advantageous for activities such as flying airplanes and driving automobiles, as they allow the operator a clear view of the instrument panel, low in his line of sight and usually hidden in shadow, while still reducing glare from the view out the windscreen. The Independent (London), has also referred to these style of sunglasses as the Murphy Lens./ref> Double gradient lenses are dark at the top, light in the middle and dark at the bottom. Gradients should not be confused with bifocals and progressive lenses.
Flip-up
Flip-up sunglasses add the benefits of sunglasses to corrective eyeglasses, allowing the wearer to flip up the tinted lenses for indoor use. Alternatives include: #Clip-on glasses, clip-on glasses, and wrap around sunglasses that fit over the eyeglasses.Mirrored
Mirrored lenses have a metallic, partially reflective coating on the outer surface combined with a tinted glass lens. Mirrored lenses of different colors can expand the range of fashion styles.
Other names
There are various words referring to eyepieces with darkened lenses: * Shades is a term used in North America. * Glares is a term popular in India if the glass is dark. * Glints is a term for glasses originating from the "glint" that is noticeable when somebody wearing glasses moves their head. * 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 sun spectacles. * Sunglass a monocle version. * 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 used in Australian, South African, UK and New Zealand slang. * Smoked spectacles usually refers to the darkened eyepieces worn by blind people. * Solar shields Usually refers to models of sunglasses with large lenses. * Stunna shades: Used as a slang term in the hyphy movement, usually referring to sunglasses with oversized lenses. * Glecks is Scottish slang for glasses or sunglasses. * Cooling glasses is a term used in Southern India (predominantly Kerala) and the Middle East for sunglasses.Producers
Most brands are produced by two producers: * Luxottica Group (revenue €9 billion (2018)) * Safilo Group (revenue €1 billion (2018)) While other niche players are: * Kaenon Polarized * Maui Jim * Serengeti (sunglasses brand), Serengeti * ic! berlin * Randolph Engineering, Inc. * William PainterSee also
* Eye patch * Goggles *Photochromic lens
A photochromic lens is an optical lens that darkens on exposure to light of sufficiently high frequency, most commonly ultraviolet (UV) radiation. In the absence of activating light, the lenses return to their clear state. Photochromic lenses may ...
* Photosensitive glass
* Pulfrich effect
References
External links
"What Makes a Good Pair of Sunglasses?"
by George W. Waltz; April 1951 ''Popular Science'' article (pp. 141–146) on sunglasses and the method of mass production at that time period.
ISO 12312-1
{{Authority control Sunglasses, American inventions Ancient Roman technology English inventions Eyewear Fashion accessories Ophthalmology Prevention Sun, Glasses