Sunglasses

Sunglasses

Overview

Sunglasses or sun glasses are a form of protective eyewear
Eye protection
Eye protection is protective gear for the eyes, which comes in many types depending upon the threat that is to be reduced. The threats can be particles, light, wind blast, heat, sea spray or some type of ball or puck used in sports...

 designed primarily to prevent bright sunlight
Sunlight
Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.When the direct solar radiation is not blocked...

 and high-energy visible light from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously termed spectacles or glasses
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...

 exist, featuring lenses that are colored, polarized or darkened. In the early 20th century they were also known as sun cheaters (cheaters being an America
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

n slang term for glasses).

Many people find direct sunlight too bright for comfort during outdoor activities.
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Encyclopedia

Sunglasses or sun glasses are a form of protective eyewear
Eye protection
Eye protection is protective gear for the eyes, which comes in many types depending upon the threat that is to be reduced. The threats can be particles, light, wind blast, heat, sea spray or some type of ball or puck used in sports...

 designed primarily to prevent bright sunlight
Sunlight
Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.When the direct solar radiation is not blocked...

 and high-energy visible light from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously termed spectacles or glasses
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...

 exist, featuring lenses that are colored, polarized or darkened. In the early 20th century they were also known as sun cheaters (cheaters being an America
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

n slang term for glasses).

Many people find direct sunlight too bright for comfort during outdoor activities. Healthcare professionals recommend eye protection whenever the sun comes out to protect the eyes from ultraviolet radiation
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 (UV) and blue light, which can cause several serious eye problems. Sunglasses have long been associated with celebrities
Celebrity
A celebrity, also referred to as a celeb in popular culture, is a person who has a prominent profile and commands a great degree of public fascination and influence in day-to-day media...

 and film
Film
A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects...

 actor
Actor
An actor is a person who acts in a dramatic production and who works in film, television, theatre, or radio in that capacity...

s primarily from a desire to mask their identity. Since the 1940s sunglasses have been popular as a fashion accessory, especially on the beach
Beach
A beach is a geological landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones...

.

Precursors



In prehistoric and historic time, Inuit peoples wore flattened walrus ivory "glasses," looking through narrow slits to block harmful reflected rays of the sun.

It is said that the Roman emperor Nero
Nero
Nero , was Roman Emperor from 54 to 68, and the last in the Julio-Claudian dynasty. Nero was adopted by his great-uncle Claudius to become his heir and successor, and succeeded to the throne in 54 following Claudius' death....

 liked to watch gladiator
Gladiator
A gladiator 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 gladiators were volunteers who risked their legal and social standing and their lives by appearing in the...

 fights with emerald
Emerald
Emerald is a variety of the mineral beryl colored green by trace amounts of chromium and sometimes vanadium. Beryl has a hardness of 7.5–8 on the 10 point Mohs scale of mineral hardness...

s. These, however, appear to have worked rather like mirrors.
Sunglasses made from flat panes of smoky quartz
Smoky quartz
Smoky or smokey quartz is a brown to black variety of quartz. Like other quartz gems, it is a silicon dioxide crystal. The smoky colour results from free silicon, formed from the silicon dioxide by natural irradiation.-Morion:...

, which offered no corrective powers but did protect the eyes from glare were used in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 in the 12th century or possibly earlier. Ancient documents describe the use of such crystal sunglasses by judges in ancient Chinese court
Court
A court is a form of tribunal, often a governmental institution, with the authority to adjudicate legal disputes between parties and carry out the administration of justice in civil, criminal, and administrative matters in accordance with the rule of law...

s to conceal their facial expressions while questioning witnesses.

James Ayscough
James Ayscough
James Ayscough 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 was in London between 1740 and 1759. Around the year 1752, James Ayscough...

 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 blue- or green-tinted glass could correct for specific vision impairments. Protection from the Sun's rays was not a concern for him.

Yellow/amber and brown-tinted spectacles were also a commonly prescribed item for people with syphilis
Syphilis
Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact; however, it may also be transmitted from mother to fetus during pregnancy or at birth, resulting in congenital syphilis...

 in the 19th and early 20th centuries because sensitivity to light was one of the symptoms of the disease.

Modern developments


In the early 1900s, the use of sunglasses started to become more widespread, especially among stars of movies. It is commonly believed that this was to avoid recognition by fans, but an alternative reason sometimes given is that they often had red eyes from the powerful arc lamp
Arc lamp
"Arc lamp" or "arc light" is the general term for a class of lamps that produce light by an electric arc . The lamp consists of two electrodes, first made from carbon but typically made today of tungsten, which are separated by a gas...

s that were needed due to the extremely slow speed film stocks used. The stereotype persisted long after improvements in film quality and the introduction of ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 filters had eliminated this problem.
Inexpensive mass-produced sunglasses were introduced to America by Sam Foster
Foster Grant
Foster Grant, or FosterGrant, is a brand of eyewear founded by Sam Foster in 1919. The FosterGrant brand is a subsidiary company of FGX International, a consumer goods wholesaler with headquarters in Smithfield, Rhode Island, USA....

 in 1929. Foster found a ready market on the beach
Beach
A beach is a geological landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones...

es of Atlantic City, New Jersey
Atlantic City, New Jersey
Atlantic City is a city in Atlantic County, New Jersey, United States, and a nationally renowned resort city for gambling, shopping and fine dining. The city also served as the inspiration for the American version of the board game Monopoly. Atlantic City is located on Absecon Island on the coast...

, where he began selling sunglasses under the name Foster Grant
Foster Grant
Foster Grant, or FosterGrant, is a brand of eyewear founded by Sam Foster in 1919. The FosterGrant brand is a subsidiary company of FGX International, a consumer goods wholesaler with headquarters in Smithfield, Rhode Island, USA....

 from a Woolworth
F. W. Woolworth Company
The F. W. Woolworth Company was a retail company that was one of the original American five-and-dime stores. The first successful Woolworth store was opened on July 18, 1879 by Frank Winfield Woolworth in Lancaster, Pennsylvania, as "Woolworth's Great Five Cent Store"...

 on the Boardwalk.
Polarized
Polarizer
A polarizer is an optical filter that passes light of a specific polarization and blocks waves of other polarizations. It can convert a beam of light of undefined or mixed polarization into a beam with well-defined polarization. The common types of polarizers are linear polarizers and circular...

 sunglasses first became available in 1936, when Edwin H. Land began experimenting with making lenses with his patented Polaroid filter.

Visual clarity and comfort


Sunglasses can improve visual comfort and visual clarity by protecting the eye from glare
Glare (vision)
Glare is difficulty seeing in the presence of bright light such as direct or reflected sunlight or artificial light such as car headlamps at night. Because of this, some cars include mirrors with automatic anti-glare functions....

.

Various types of disposable sunglasses are dispensed to patients after receiving mydriatic
Mydriasis
Mydriasis is a dilation of the pupil due to disease, trauma or the use of drugs. Normally, the pupil dilates in the dark and constricts in the light to respectively improve vividity at night and to protect the retina from sunlight damage during the day...

 eye drops during eye examination
Eye examination
An eye examination is a battery of tests performed by an ophthalmologist, optometrist, or orthoptist assessing vision and ability to focus on and discern objects, as well as other tests and examinations pertaining to the eyes....

s.

The lenses of polarized sunglasses reduce glare reflected at some angles off shiny non-metallic surfaces such as water. They are popular among fishermen because they allow wearers to see into water when normally only glare would be seen.

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, snow blindness
Snow blindness
Photokeratitis or ultraviolet keratitis is a painful eye condition caused by exposure of insufficiently protected eyes to the ultraviolet rays from either natural or artificial sources. Photokeratitis is akin to a sunburn of the cornea and conjunctiva, and is not usually noticed until several...

, cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...

s, pterygium, and various forms of eye cancer
Ocular oncology
Ocular oncology is the branch of medicine dealing with tumors relating to the eye and its adnexa. Eye cancer can affect all parts of the eye.-Origin and location:...

. 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 99-100 % of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses which meet this requirement are often labeled as "UV400." This is slightly more protection than the widely used standard of the European Union (see below), which requires that 95 % of the radiation up to only 380 nm must be reflected or filtered out.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]. 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]. 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
Solar eclipse
As seen from the Earth, a solar eclipse occurs when the Moon passes between the Sun and the Earth, and the Moon fully or partially blocks the Sun as viewed from a location on Earth. This can happen only during a new moon, when the Sun and the Moon are in conjunction as seen from Earth. At least...

.

More recently, high-energy visible light (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. Some manufacturers already design to block blue light; the insurance company Suva
Suva (insurer)
The Suva, headquartered in Lucerne, is a public sector insurer and leading provider of health care coverage for employees in case of accidents in Switzerland....

, which covers most Swiss
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

 employees, asked eye experts around Charlotte Remé (ETH Zürich
ETH Zurich
The Swiss Federal Institute of Technology Zurich or ETH Zürich is an engineering, science, technology, mathematics and management university in the City of Zurich, Switzerland....

) 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 cancer
Skin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...

. This is due to the eyes being tricked into producing less melanocyte
Melanocyte
-External links: - "Eye: fovea, RPE" - "Integument: pigmented skin"...

-stimulating hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

 in the body.

Assessing the protection of sunglasses


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
Optician
An optician is a person who is trained to fill prescriptions for eye correction in the field of medicine, also known as a dispensing optician or optician, dispensing...

. Several standards for sunglasses (see 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
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...

" 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 and blue light as compared to 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 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 and Consumer Commission
Australian Competition and Consumer Commission
The Australian Competition and Consumer Commission is an independent authority of the Australia government. It was established in 1995 with the amalgamation of the Australian Trade Practices Commission and the Prices Surveillance Authority to administer the Trade Practices Act 1974...

 has also reported that "[c]onsumers 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 did expensive Salvatore Ferragamo
Salvatore Ferragamo
Salvatore Ferragamo was a Florentine and Italian shoe designer. He worked with many Hollywood stars in the 1920s, before returning to Italy to found the eponymous company making unique hand-made footwear. His scientific and creative approach to shoes spawned many innovations such as the wedge heel...

 shades.

Further functions of sunglasses


While non-tinted glasses are very rarely worn without the practical purpose of correcting eyesight or protecting one's eyes, sunglasses have become popular for several further reasons, and are sometimes worn even indoors or at night.

Sunglasses can be worn to hide one's eyes. They can make eye contact
Eye contact
Eye contact is a meeting of the eyes between two individuals.In human beings, eye contact is a form of nonverbal communication and is thought to have a large influence on social behavior. Coined in the early to mid-1960s, the term has come in the West to often define the act as a meaningful and...

 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 ("cool
Cool (aesthetic)
Something regarded as cool is an admired aesthetic of attitude, behavior, comportment, appearance and style, influenced by and a product of the Zeitgeist. Because of the varied and changing connotations of cool, as well its subjective nature, the word has no single meaning. It has associations of...

") in some circles. Eye contact can be avoided even more effectively by using mirrored sunglasses. Sunglasses can also be used to hide emotions; this can range from hiding blinking to hiding weeping
Crying
Crying is shedding tears as a response to an emotional state in humans. The act of crying has been defined as "a complex secretomotor phenomenon characterized by the shedding of tears from the lacrimal apparatus, without any irritation of the ocular structures"...

 and its resulting red eyes. In all cases, hiding one's eyes has implications for nonverbal communication
Nonverbal communication
Nonverbal communication is usually understood as the process of communication through sending and receiving wordless messages. Messages can be communicated through gestures and touch , by body language or posture, by facial expression and eye contact...

.
Fashion trends can be another reason for wearing sunglasses, particularly designer sunglasses, but not always. Sunglasses of particular shapes may be in vogue as a fashion accessory
Fashion accessory
Fashion accessories are decorative items that supplement and complement clothes, such as jewelery, gloves, handbags, hats, belts, scarves, wigs, watches, sunglasses, pins, stockings, bow ties, hand fans, leg warmers, leggings, neckties, suspenders, and tights....

. Fashion trends can also draw on the "cool" image of sunglasses.

People may also wear sunglasses to hide an abnormal appearance of their eyes. This can be true for people with severe visual impairment, such as the blind
Blindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...

, who may wear sunglasses to avoid making others uncomfortable. The assumption is that it may be more comfortable for another person not to see the hidden eyes rather than see abnormal eyes or eyes which seem to look in the wrong direction. People may also wear sunglasses to hide dilated or contracted pupils, bloodshot eyes due to drug use, recent physical abuse (such as a black eye
Black eye
A black eye , or or 'shiner', is bruising around the eye commonly due to an injury to the face rather than eye injury. The name is given due to the color of bruising. The so-called black eye is caused by bleeding beneath the skin and around the eye...

), exophthalmos
Exophthalmos
Exophthalmos is a bulging of the eye anteriorly out of the orbit. Exophthalmos can be either bilateral or unilateral . Measurement of the degree of exophthalmos is performed using an exophthalmometer...

 (bulging eyes), a cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...

, or eyes which jerk uncontrollably (nystagmus).

Standards for sunglasses


There are three major sunglass standards, which are popularly known mostly as a reference for sunglass protection from UV radiation; the standards do, however, also include further requirements. A worldwide ISO
International Organization for Standardization
The International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...

 standard does not yet exist, but by 2004, attempts to introduce such standard have led to a respective ISO standards committee, subcommittee, technical committee, and several working groups. Sunglasses sold in the United States are regulated by the Food and Drug Administration and are required to conform to safety standards.

The Australian Standard is AS/NZS 1067:2003 Sunglasses and fashion spectacles. 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. Australia introduced the world's first national standards for sunglasses in 1971. They were subsequently updated and expanded, leading in 1990 to AS 1067.1-1990 Sunglasses and fashion spectacles (incl. Part 1 Safety Requirements and Part 2 Performance Requirements), which was superseded in part in 2003 by AS/NZS 1067:2003 Sunglasses and fashion spectacles. The 2003 update made the Australian standard relatively similar to the European standard. This step opened the European market to Australian-made sunglasses, but the standard also maintained requirements considered specific to Australia's climate.

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 a CE mark
CE mark
CE marking is a mandatory conformity mark for products placed on the market in the European Economic Area . With the CE marking on a product the manufacturer ensures that the product conforms with the essential requirements of the applicable EC directives...

. There is no 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 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).

The U.S. standard is ANSI
American National Standards Institute
The American National Standards Institute 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 organization also coordinates U.S. standards with international...

 Z80.3-2001, which includes three transmittance categories. According to the ANSI Z80.3-2001 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.

Special-use sunglasses



Sunglasses in sports


As do corrective glasses
Corrective lens
A corrective lens is a lens worn in front of the eye, mainly used to treat myopia, hyperopia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye. Contact lenses are worn directly on the surface of the eye...

, 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
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 in woodworking. They are often used in snow sports as well,...

 or water eyewear) are specially adapted for use in turbulent water, such as the surf
Breaking wave
In fluid dynamics, a breaking wave is a wave whose amplitude reaches a critical level at which some process can suddenly start to occur that causes large amounts of wave energy to be transformed into turbulent kinetic energy...

 or whitewater
Whitewater
Whitewater is formed in a rapid, when a river's gradient increases enough to disturb its laminar flow and create turbulence, i.e. form a bubbly, or aerated and unstable current; the frothy water appears white...

. In addition to the features for sports glasses, water sunglasses can have increased buoyancy
Buoyancy
In physics, buoyancy is a force exerted by a fluid that opposes an object's weight. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus a column of fluid, or an object submerged in the fluid, experiences greater pressure at the bottom of 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
Surfing' is a surface water sport in which the surfer rides a surfboard on the crest and face of a wave which is carrying the surfer towards the shore...

, windsurfing
Windsurfing
Windsurfing or sailboarding is a surface water sport that combines elements of surfing and sailing. It consists of a board usually two to four metres long, powered by the orthogonal effect of the wind on a sail. The rig is connected to the board by a free-rotating universal joint and comprises a...

, kiteboarding
Kite landboarding
Kite landboarding also known as Land kiteboarding or flyboarding, is based on the ever-growing sport of Kitesurfing, where a rider on a surf-style board is pulled over water by a kite. Kite landboarding involves the use of a mountain board or landboard, which is essentially an oversized skateboard...

, wakeboarding
Wakeboarding
Wakeboarding is a surface water sport which involves riding a wakeboard over the surface of a body of water. It was developed from a combination of water skiing, snow boarding and surfing techniques....

, kayaking
Kayaking
Kayaking is the use of a kayak for moving across water. Kayaking and canoeing are also known as paddling. Kayaking is distinguished from canoeing by the sitting position of the paddler and the number of blades on the paddle...

, jet skiing
Jet ski
Jet Ski is the brand name of a personal watercraft manufactured by Kawasaki Heavy Industries. The name is sometimes mistakenly used by those unfamiliar with the personal watercraft industry to refer to any type of personal watercraft; however, the name is a valid trademark registered with the...

, bodyboarding
Bodyboarding
Bodyboarding is a surface water sport . The average board consists of a small, rectangular piece of hydrodynamic foam, sometimes containing a ridged spine called a 'stringer'...

, and water skiing
Water skiing
thumb|right|A slalom skier making a turn on a slalom waterski.Waterskiing is a sport where an individual is pulled behind a boat or a cable ski installation on a body of water, skimming the surface.-History:...

.

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
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 in woodworking. They are often used in snow sports as well,...

. 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.

Sunglasses in 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
Atmosphere
An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

. Sun protection is needed against much higher UV radiation and even against harmful infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...

 radiation, both within and outside the spacecraft. Within the spacecraft, astronauts wear sunglasses with darker lenses and a thin protective gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 coating. During space walks, the visor of the astronauts' helmets, which also has a thin gold coating for extra protection, functions as strong sunglasses. Also the frames of glasses in space need to satisfy special requirements. Similar to sports glasses, they should be flexible and durable, and have a reliable fit that can withstand zero-gravity conditions. Some astronauts wear glasses underneath tight helmets and in their space suits, which requires a specially well-fitting frame: Once inside the spacesuit, they cannot touch their heads to push slipped glasses back into place, sometimes for a duration of up to 10 hours while working in zero-gravity. Another risk is that small pieces (screws, glass particles) of the glasses may dislodge and then float into an astronaut's respiratory system. While some of these challenges, especially wearing glasses inside a sunlight-protected spacesuit helmet, may relate to corrective glasses and not necessarily to sunglasses, today NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 uses the same frames for both types of glasses, so that the frames have to withstand all conditions. A related challenge is that even astronauts who do not wear glasses on Earth use corrective glasses in space because zero-gravity and pressure changes temporarily affect their vision; this results in 90 % of astronauts wearing glasses in space, as opposed to 70 % on Earth.

The first sunglasses used in a Moon landing were the original Pilot Sunglasses produced by American Optical. In 1969, they were on board the Eagle, the lunar landing module of the first manned mission to land on the Moon (Apollo 11
Apollo 11
In early 1969, Bill Anders accepted a job with the National Space Council effective in August 1969 and announced his retirement as an astronaut. At that point Ken Mattingly was moved from the support crew into parallel training with Anders as backup Command Module Pilot in case Apollo 11 was...

). – NASA research primarily by scientists James B. Stephens and Charles G. Miller at the Jet Propulsion Laboratory (JPL)
Jet Propulsion Laboratory
Jet Propulsion Laboratory is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. The facility is headquartered in the city of Pasadena on the border of La Cañada Flintridge and Pasadena...

 resulted in special lenses that protected against the light in space or the light during laser and welding work. The lenses used colored dyes and small zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 oxide
Oxide
An oxide is a chemical compound that contains at least one oxygen atom in its chemical formula. Metal oxides typically contain an anion of oxygen in the oxidation state of −2....

 particles; zinc oxide absorbs ultaviolet light and is also used in sunscreen
Sunscreen
Sunblock is a lotion, spray, gel or other topical product that absorbs or reflects some of the sun's ultraviolet radiation on the skin exposed to sunlight and thus helps protect against sunburn...

 lotions. The research was later broadened to further terrestrial applications, e.g., deserts, mountains, or fluorescent-lighted offices, and the technology has been 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, combined with specially dark lenses developed jointly by the company and "the" NASA optometrist Keith Manuel. The frame is noteworthy in that it is very light, weighing 1.8 grams, and contains neither screws nor hinges, so that no small pieces can loosen.

Construction




Lens


The color
Color
Color or colour is the visual perceptual property corresponding in humans to the categories called red, green, blue and others. Color derives from the spectrum of light interacting in the eye with the spectral sensitivities of the light receptors...

 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
Color vision
Color vision is the capacity of an organism or machine to distinguish objects based on the wavelengths of the light they reflect, emit, or transmit...

, 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.
  • Orange and yellow lenses increase both contrast and depth perception. They also increase color distortion. Yellow lenses are used by pilot
    Aviator
    An aviator is a person who flies an aircraft. The first recorded use of the term was in 1887, as a variation of 'aviation', from the Latin avis , coined in 1863 by G. de la Landelle in Aviation Ou Navigation Aérienne...

    s, boaters, fishers
    Fishing
    Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....

    , shooters
    Shooting
    Shooting is the act or process of firing rifles, shotguns or other projectile weapons such as bows or crossbows. Even the firing of artillery, rockets and missiles can be called shooting. A person who specializes in shooting is a marksman...

    , and hunters
    Hunting
    Hunting is the practice of pursuing any living thing, usually wildlife, for food, recreation, or trade. In present-day use, the term refers to lawful hunting, as distinguished from poaching, which is the killing, trapping or capture of the hunted species contrary to applicable law...

     for their contrast enhancement and width perception properties.
  • Blue or purple lenses are mainly cosmetic.

With the introduction of office computing
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...

, ergonomists
Ergonomics
Ergonomics is the study of designing equipment and devices that fit the human body, its movements, and its cognitive abilities.The International Ergonomics Association defines ergonomics as follows:...

 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
Age-related macular degeneration is a medical condition which usually affects older adults and results in a loss of vision in the center of the visual field because of damage to the retina. It occurs in “dry” and “wet” forms. It is a major cause of blindness and visual impairment in older adults...

 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
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

 melatonin
Melatonin
Melatonin , also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes...

. 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
Circadian rhythm
A circadian rhythm, popularly referred to as body clock, is an endogenously driven , roughly 24-hour cycle in biochemical, physiological, or behavioural processes. Circadian rhythms have been widely observed in plants, animals, fungi and cyanobacteria...

.

Some models have polarized lenses, made of Polaroid polarized plastic sheeting, to reduce glare caused by light reflected from polarizing surfaces such as water (see Brewster's angle
Brewster's angle
Brewster's 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 is incident at this angle, the light that is reflected from the surface is therefore perfectly...

 for how this works) as well as by polarized diffuse sky radiation
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 suspensoids in the atmosphere. It is also called skylight, diffuse skylight, or sky radiation and is the reason for changes in the colour of the sky...

 (skylight). This can be especially useful when fishing, for which the ability to see beneath the surface of the water is crucial.

A mirror
Mirror
A mirror is an object that reflects light or sound in a way that preserves much of its original quality prior to its contact with the mirror. Some mirrors also filter out some wavelengths, while preserving other wavelengths in the reflection...

ed coating can also 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. 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
Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...

, plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

, or SR-91. Plastic lenses are typically made from acrylic
Acrylic glass
Poly is a transparent thermoplastic, often used as a light or shatter-resistant alternative to glass. It is sometimes called acrylic glass. Chemically, it is the synthetic polymer of methyl methacrylate...

, polycarbonate
Polycarbonate
PolycarbonatePhysical PropertiesDensity 1.20–1.22 g/cm3Abbe number 34.0Refractive index 1.584–1.586FlammabilityV0-V2Limiting oxygen index25–27%Water absorption – Equilibrium0.16–0.35%Water absorption – over 24 hours0.1%...

, CR-39
CR-39
CR-39, or allyl diglycol carbonate , is a plastic polymer commonly used in the manufacture of eyeglass lenses. The abbreviation stands for “Columbia Resin #39,” because it was the 39th formula of a thermosetting plastic developed by the Columbia Resins project in 1940.The first commercial use of...

 or polyurethane
Polyurethane
A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...

. 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
Kaenon Polarized
Kaenon Polarized is a luxury performance polarized sunglasses and lens brand based in Newport Beach, CA . The company was founded in 2001 by elite sailors, and brothers, Steve and Darren Rosenberg...

 in 2001. It exhibits all of the benefits of the other lens materials without the flaws. Kaenon's unique 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.

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
Corrective lens
A corrective lens is a lens worn in front of the eye, mainly used to treat myopia, hyperopia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye. Contact lenses are worn directly on the surface of the eye...

es or glasses
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...

 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 lenses gradually darken in bright light.



Frames


Frames are generally made of plastic, nylon
Nylon
Nylon is a generic designation for a family of synthetic polymers known generically as polyamides, first produced on February 28, 1935, by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station...

, a metal
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

 or a metal alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

. 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 (device)
A spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication...

 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
Synthetic rubber
Synthetic rubber is is any type of artificial elastomer, invariably a polymer. An elastomer is a material with the mechanical property that it can undergo much more elastic deformation under stress than most materials and still return to its previous size without permanent deformation...

 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
Oakley, Inc.
Oakley, Inc., based in Foothill Ranch, California, makes sport equipment including sunglasses, sports visors, and ski goggles, as well as watches, clothing, bags, backpacks, shoes, prescription glasses, football and hockey eyewear, Golf gear and other accessories...

, for example, has straight resting hooks on all their glasses, preferring to call them "earstems".

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 colour. 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.

Aviator sunglasses



Aviator sunglasses feature oversize teardrop-shaped lenses and a thin metal frame. The design was introduced in 1936 by the American Optical Eyewear company for issue to U.S. military aviator
Aviator
An aviator is a person who flies an aircraft. The first recorded use of the term was in 1887, as a variation of 'aviation', from the Latin avis , coined in 1863 by G. de la Landelle in Aviation Ou Navigation Aérienne...

s. As a fashion statement, aviator sunglasses are often made in mirrored, colored, and wrap-around styles.

In addition to pilots, Aviator-style sunglasses gained popularity with young people in the late 1960s and continue to be popular, with only a brief fall in demand during the 1990s.

Clip-on glasses


Clip-on glasses are a form of tinted glasses that can be clipped on to eyeglasses for protection from the Sun. The best protection is polarized lens with 1.1mm. An alternative are 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
The Independent
The Independent is a British national morning newspaper published in London by Independent Print Limited, owned by Alexander Lebedev since 2010. It is nicknamed the Indy, while the Sunday edition, The Independent on Sunday, is the Sindy. Launched in 1986, it is one of the youngest UK national daily...

 (London), has also referred to these style of sunglasses as the Murphy Lens.

Double gradient lenses are dark at the top, light in the middle and dark at the bottom.

Gradients should not be confused with bifocal
Bifocal
Bifocal may refer to:* Bifocals, eyeglasses whose corrective lenses each contain regions with two distinct optical powers* Fundamental matrix , which sometimes is referred to as "bifocal tensor"...

s and progressive lenses.

Flip-up sunglasses


Flip-up sunglasses add the benefits of sunglasses to corrective eyeglasses, allowing the wearer to flip up the tinted lenses for indoor use. An alternative are clip-on glasses.

Mirrored sunglasses



Mirrored lenses, having a metallic, partially reflective coating on the outer surface, combined with a tinted glass lens, are an alternative to polarization for UV protection, improving contrast when depth perception is important such as seeing moguls and ice while skiing or snowboarding. The mirrored lens reflects glare to protect the eyes, but improves the ability to see contrasts, and mirrored lenses of different colors can expand the range of fashion styles. Their popularity with police
Police
The police is a personification of the state designated to put in practice the enforced law, protect property and reduce civil disorder in civilian matters. Their powers include the legitimized use of force...

 officers in the United States has earned them the nickname "cop shades". The two most popular styles are dual lenses set in metal frames (which are often confused with Aviators, see above) and "Wraparounds" (see below).

Oversized sunglasses


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
Captain Fantastic and the Brown Dirt Cowboy
Captain Fantastic and the Brown Dirt Cowboy is the ninth studio album by British singer/songwriter Elton John, released in 1975. It debuted at number 1 on the U.S. Pop Albums chart, the first album ever to do so, and stayed there for seven weeks. It was certified Gold on 5/21/1975 and was...

 act.

In the early twenty-first century 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
Jacqueline Kennedy Onassis
Jacqueline Lee Bouvier "Jackie" Kennedy Onassis was the wife of the 35th President of the United States, John F. Kennedy, and served as First Lady of the United States during his presidency from 1961 until his assassination in 1963. Five years later she married Greek shipping magnate Aristotle...

 in the 1960s. The glasses continue to be popular with women, and celebrities may use them, ostensibly to hide from paparazzi.

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 a fad
FAD
In biochemistry, flavin adenine dinucleotide is a redox cofactor involved in several important reactions in metabolism. FAD can exist in two different redox states, which it converts between by accepting or donating electrons. The molecule consists of a riboflavin moiety bound to the phosphate...

 in the early 1980s. Instead of tinted lenses, they decrease sun exposure by means of a set of parallel, horizontal shutters (like a small window shutter
Window shutter
A window shutter is a solid and stable window covering usually consisting of a frame of vertical stiles and horizontal rails...

). Analogous to Inuit goggles (see 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
John Lennon
John Winston Lennon, MBE was an English musician and singer-songwriter who rose to worldwide fame as one of the founding members of The Beatles, one of the most commercially successful and critically acclaimed acts in the history of popular music...

 glasses", "Ozzy Glasses", after Ozzy Osbourne
Ozzy Osbourne
John Michael "Ozzy" Osbourne is an English vocalist, whose musical career has spanned over 40 years. Osbourne rose to prominence as lead singer of the pioneering English heavy metal band Black Sabbath, whose radically different, intentionally dark, harder sound helped spawn the heavy metal...

 or, occasionally, "Granny Glasses") were a type of psychedelic
Psychedelic
The term psychedelic is derived from the Greek words ψυχή and δηλοῦν , translating to "soul-manifesting". A psychedelic experience is characterized by the striking perception of aspects of one's mind previously unknown, or by the creative exuberance of the mind liberated from its ostensibly...

 art wire-rim sunglasses that were often worn, usually for purely aesthetic reasons, by members of the 1960s counterculture, as well as by opponents of segregation. Pop icons such as Mick Jagger
Mick Jagger
Sir Michael Philip "Mick" Jagger is an English musician, singer and songwriter, best known as the lead vocalist and a founding member of The Rolling Stones....

, Roger Daltrey
Roger Daltrey
Roger Harry Daltrey, CBE , is an English singer and actor, best known as the founder and lead singer of English rock band The Who. He has maintained a musical career as a solo artist and has also worked in the film industry, acting in a large number of films, theatre and television roles and also...

, John Lennon
John Lennon
John Winston Lennon, MBE was an English musician and singer-songwriter who rose to worldwide fame as one of the founding members of The Beatles, one of the most commercially successful and critically acclaimed acts in the history of popular music...

, Jerry Garcia
Jerry Garcia
Jerome John "Jerry" Garcia was an American musician best known for his lead guitar work, singing and songwriting with the band the Grateful Dead...

, Boy George
Boy George
Boy George is a British singer-songwriter who was part of the English New Romantic movement which emerged in the early 1980s. He helped give androgyny an international stage with the success of Culture Club during the 1980s. His music is often classified as blue-eyed soul, which is influenced by...

, Liam Gallagher
Liam Gallagher
William John Paul "Liam" Gallagher is an English musician and singer-songwriter, the former frontman of the English rock band Oasis and currently of the band Beady Eye. Gallagher's erratic behaviour, distinctive singing style, and abrasive attitude have been the subject of commentary in the press...

 and Ozzy Osbourne
Ozzy Osbourne
John Michael "Ozzy" Osbourne is an English vocalist, whose musical career has spanned over 40 years. Osbourne rose to prominence as lead singer of the pioneering English heavy metal band Black Sabbath, whose radically different, intentionally dark, harder sound helped spawn the heavy metal...

, all wore teashades. The original teashade design was made up of medium-sized, perfectly round lenses, supported by pads on the bridge of the nose and a thin wire frame. When teashades became popular in the late 1960s, they were often elaborated: Lenses were elaborately colored, mirrored, and produced in excessively large sizes, and with the wire earpieces exaggerated. A uniquely-colored or darkened glass lens was usually preferred. Modern versions tend to have plastic lenses, as do many other sunglasses. Teashades are hard to find in shops today; however, they can still be found at many costume Web sites and in some countries.

The term has now fallen into disuse, although references can still be found in literature of the time. "Teashades" was also used to describe glasses worn to hide the effects of marijuana (conjunctival injection) or bloodshot eyes or the effects of opiates such as heroin (pupillary constriction).

The glasses worn by Seraph
Seraph (The Matrix)
Seraph is the name of a fictional character in the science-fiction Matrix universe. He is portrayed as the personification of a sophisticated challenge-handshake authentication protocol which guards the Oracle....

 in the Matrix films are teashades. Teashades are briefly referenced during a police training seminar in Hunter S. Thompson's
Hunter S. Thompson
Hunter Stockton Thompson was an American journalist and author who wrote The Rum Diary , Fear and Loathing in Las Vegas and Fear and Loathing on the Campaign Trail '72 .He is credited as the creator of Gonzo journalism, a style of reporting where reporters involve themselves in the action to...

 novel Fear and Loathing in Las Vegas
Fear and Loathing in Las Vegas (novel)
Fear and Loathing in Las Vegas: A Savage Journey to the Heart of the American Dream is an autobiographical novel by Hunter S. Thompson, illustrated by Ralph Steadman. The book is a roman à clef, rooted in autobiographical incidents. The story follows its protagonist, Raoul Duke, and his attorney, Dr...

. Mickey Knox in Natural Born Killers
Natural Born Killers
Natural Born Killers is a 1994 crime/black comedy film directed by Oliver Stone about two victims of traumatic childhoods who became lovers and psychopathic serial killers, and are irresponsibly glorified by the mass media...

 wears red teashades. Lara Croft
Lara Croft
Lara Croft is a fictional character and the protagonist of the Square Enix video game series Tomb Raider. She is presented as a beautiful, intelligent, and athletic British archaeologist-adventurer who ventures into ancient, hazardous tombs and ruins around the world...

 from the video-game Tomb Raider
Tomb Raider
Tomb Raider is an action-adventure video game developed by Core Design and published by Eidos Interactive. It was originally released in 1996 for the Sega Saturn, with MS-DOS and PlayStation versions following shortly thereafter...

 is seen wearing Teashade sunglasses. Vash the Stampede (Trigun) wears yellow-lens teashades. The iconic sunglasses of Spider Jerusalem
Spider Jerusalem
Spider Jerusalem is a fictional character and the protagonist of the comic book Transmetropolitan, created by writer Warren Ellis and artist Darick Robertson, introduced under the now-defunct Helix imprint of DC Comics before being moved to the Vertigo imprint.-Background:Spider is a renegade gonzo...

 are a variation of teashades. Jean Reno wears black teashades in the movie Léon
Léon (film)
Léon is a 1994 French thriller film written and directed by Luc Besson...

(The Professional). Main character of Hellsing, Alucard
Alucard
Alucard may refer to:*Count Alucard , the title character in the 1943 film Son of Dracula and other works....

, wears red-lensed teashades. Recently, actress and fashion icon Mary-Kate Olsen
Mary-Kate Olsen
Mary-Kate Olsen is an American actress, producer, author and fashion designer. She made her career debut in 1987 alongside her twin sister Ashley Olsen in the television series Full House...

 and pop music singer Lady Gaga
Lady GaGa
Stefani Joanne Angelina Germanotta , better known by her stage name Lady Gaga, is an American singer and songwriter. Born and raised in New York City, she primarily studied at the Convent of the Sacred Heart and briefly attended New York University's Tisch School of the Arts before withdrawing to...

 have been seen wearing several variations of teashades. Howard Stern was also known for wearing teashades in the early to mid 90's and never taking them off in public.

Wayfarers



The Ray-Ban Wayfarer is a 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 and were famously worn by James Dean and other actors. The original frames were black; frames in many different colours were later introduced.

Wraparound sunglasses


Wraparounds are a specific design of sunglasses. They are characterized by a single, smooth, semi-circular lens that covers both eyes and much of the same area of the face covered by protective goggles. The lens is usually combined with a minimal plastic frame and single piece of plastic serving as a nosepiece. As an alternative, the glasses can have two lenses, but the design evokes the same semicircle. Wraparound sunglasses are also quite popular in the world of extreme sport
Extreme sport
An extreme sport is a popular term for certain activities perceived as having a high level of inherent danger...

s.

Other names for sunglasses



There are various words referring to eyepieces with darkened lenses:
  • Shades is probably the most widely used term for sunglasses 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 Australian, South African, UK and New Zealand slang
    Slang
    Slang is the use of informal words and expressions that are not considered standard in the speaker's language or dialect but are considered more acceptable when used socially. Slang is often to be found in areas of the lexicon that refer to things considered taboo...

  • Smoked spectacles usually refers to the darkened eyepieces worn by blind
    Blindness
    Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...

     people.
  • Solar shields Usually refers to models of sunglasses with large lenses.
  • Stunna shades Used as a slang term in the hyphy
    Hyphy
    The word hyphy is Conor Devlin's preferred short word meaning "hyperactive." It was created by Bay Area rapper Keak Da Sneak when he used the term on an album he recorded in 1994. From the USA Today article: "Every record label was getting at us at that time, but we fumbled the ball," says E-40,...

     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.

Major brands

  • Oakley, Inc.
    Oakley, Inc.
    Oakley, Inc., based in Foothill Ranch, California, makes sport equipment including sunglasses, sports visors, and ski goggles, as well as watches, clothing, bags, backpacks, shoes, prescription glasses, football and hockey eyewear, Golf gear and other accessories...

  • Ray-Ban
  • Kaenon Polarized
    Kaenon Polarized
    Kaenon Polarized is a luxury performance polarized sunglasses and lens brand based in Newport Beach, CA . The company was founded in 2001 by elite sailors, and brothers, Steve and Darren Rosenberg...

  • Maui Jim
    Maui Jim
    Maui Jim is an American luxury brand of sunglasses based in Peoria, Illinois. All sets of Maui Jim sunglasses feature UV-Ray blocking polarized lenses that enhance color, and almost all lines are marketed with an oceanic, sporty theme...

  • Costa Del Mar
    Costa Del Mar
    Costa Del Mar Sunglasses, Inc. is a designer and manufacturer of high-end polarized sunglasses for use in sports such as fishing, sailing, and surfing. It was founded in 1983 and is headquartered in Daytona Beach, Florida...

  • Persol
    Persol
    Persol is an Italian eyewear company specializing in sunglasses. The name is derived from "per il sole," which, in Italian, means "for the sun." Formed in 1917 by Giuseppe Ratti, Persol originally catered to pilots and sports drivers. Presently, the company is famous for its durable sports sunglasses...

  • Serengeti
    Serengeti (sunglasses brand)
    Serengeti is a designer sunglasses brand parented by Bushnell Corporation.-Overview:The eyewear brand Serengeti was initially developed by Corning Incorporated. In 1984, Corning was considering to close down the Serengeti division because of poor performance. However, the entrepreneurial leader...

  • Luxottica
    Luxottica
    Luxottica Group S.p.A. is the world's largest eyewear company. Its best known brands include Ray-Ban, Persol and Oakley, Inc.. It also makes sunglasses and prescription frames for a multitude of designer brands such as Chanel and Prada, whose designs and trademarks are used under license...

  • ic! berlin
    Ic! berlin
    ic! berlin brillen GmbH is a German company who design and produce eyewear by hand in Berlin, Germany, and distribute worldwide. The company was founded in 1999 by Ralph Anderl....


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