Mirrored sunglasses

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A person wearing mirrored sunglasses 230320-F-ZB805-0117 - Shaw performs as core wing during Red Flag-Nellis 23-2.jpg
A person wearing 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 tint. The mirror coating decreases the amount of light passing through the tinted lens by a further 10–60%, making it especially useful for conditions of sand, water, snow, and higher altitudes. Mirrored sunglasses are one-way mirrors.[ citation needed ]

Contents

The color of the mirror coating is independent of the tint of the lenses. It is determined by the thickness and structure of the layer.

Supreme Court Police officer wearing wraparound mirrored sunglasses in Washington, DC 69.HealthCareReformProtests.SupremeCourt.WDC.27March2012 (7023020841).jpg
Supreme Court Police officer wearing wraparound mirrored sunglasses in Washington, DC

Their popularity with police officers in the United States has earned them the nickname "cop shades". The two most popular styles for these are dual lenses set in metal frames (which are often confused with aviators), and wraparound (a single, smooth, semi-circular lens that covers both eyes and much of the same area of the face covered by protective goggles, combined with a minimal plastic frame and single piece of plastic serving as a nose pad). Wraparound sunglasses are also quite popular in the world of extreme sports.

Usage in sports

Track cyclist Yuta Wakimoto wearing a helmet with a mirrored visor Yuta Wakimoto (39889769841).jpg
Track cyclist Yuta Wakimoto wearing a helmet with a mirrored visor

Many sports take advantage of the reflective material in mirrored sunglasses. Especially in outdoor sports play, mirrored sunglasses are greatly beneficial to the wearer.

Sports that can use mirrored sunglasses include:

In outdoor sports, the glare of the sun can be very intense due to the reflection of the sun from water and snow.

Reflective coating

The simplest version of a mirror coating is a single layer of a deposited thin film of a suitable metal, usually prepared by ion beam deposition, sputter deposition or vapor deposition. However, this kind of coating is very prone to scratching, and degrades, especially in a corrosive environment like salt water.

The reflective coating on mirrored glasses can be very fragile and prone to scratching. Some high-end sun glass brands can come with anti-scratch coating. There can be steps implemented to protect the sunglasses and prevent scratching or damage.

More modern reflective coatings usually have several alternating layers of specific thickness, made of dielectric materials and sometimes metals. The metal layer can be made from titanium, nickel or chromium, or from an alloy like nichrome or Inconel, and has thickness ranging from 0.5 to 9 nanometers. The dielectric layer comprises a suitable oxide, e.g. chromium oxide, silicon dioxide, or titanium dioxide; its thickness determines the reflective properties of the resulting dielectric mirror. The manufacturing process is similar to making anti-reflective coating, and mirror and anti-reflective coatings can be deposited in the same sequence of operations.

History

The main purpose of sunglasses has been, and still is, protection from the Sun's damaging UV rays. Throughout history, progression of the sunglasses began to change to serve more as a fashion stable, than eye wear for sun protection. The term "Sunglasses" began being used around the 1900s. Before then, sunglasses were being used for more extreme weather conditions, like for polar explorers or for people visiting equatorial colonies. [1]

The creation of the reflective material, Polaroid, was constructed by Edwin H. Land. [2] These reflective sunglasses worked by bouncing the light off using the reflective material. This would keep away the suns rays from the sunglasses and the wearers eyes. Most glasses also had some sort of dark tint, providing extra shade and protection from the sun. [3]

In WW2, Ray-Ban had used the anti-glare technology created by Edwin H. Land. [4] Ray-Bans were a much better substitute than goggles for the fighter pilots in WW2. The goggles did not serve the pilots much protection from the sun, thus weakening their performance. When in higher altitudes, the goggles would also be damaged by freezing over. The new design of the cockpit allowed the goggle design to be thrown out completely and allow Ray-Bans to be the main source of protection. [5]

Cyberpunk

Cyberpunk can be classified as a sub-genre of science fiction, normally a futuristic society that deals heavily with technology. [6] Mirrored glasses had become a staple for the cyberpunk culture and style. [7] Popular movies like The Matrix and Terminator could be seen using cyberpunk themes. One of the main characters of the movie The Matrix sports the mirrored sunglasses throughout the movie. [8] One early cyberpunk short story anthology, edited by Bruce Sterling, is called Mirrorshades

See also

Related Research Articles

<span class="mw-page-title-main">Mirror</span> Object that reflects an image

A mirror, also known as a 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 image in an equal yet opposite angle from which the light shines upon it. This allows the viewer to see themselves or objects behind them, or even objects that are at an angle from them but out of their field of view, such as around a corner. Natural mirrors have existed since prehistoric times, such as the surface of water, but people have been manufacturing mirrors out of a variety of materials for thousands of years, like stone, metals, and glass. In modern mirrors, metals like silver or aluminium are often used due to their high reflectivity, applied as a thin coating on glass because of its naturally smooth and very hard surface.

<span class="mw-page-title-main">Corrective lens</span> Type of lens to improve visual perception

A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, 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. Intraocular lenses are surgically implanted most commonly after cataract removal but can be used for purely refractive purposes.

<span class="mw-page-title-main">Glasses</span> Form of vision aid

Glasses, also known as eyeglasses or spectacles, are vision eyewear with clear or tinted lenses 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 or temple pieces, that rest over the ears.

<span class="mw-page-title-main">Binoculars</span> Pair of telescopes mounted side-by-side

Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes when viewing distant objects. Most binoculars are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal-mounted military models.

<span class="mw-page-title-main">Sunglasses</span> Eyewear for protecting against bright light

Sunglasses or sun glasses are a form of protective eyewear designed primarily to prevent bright sunlight and high-energy visible light from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously termed spectacles or glasses exist, featuring lenses that are colored, polarized or darkened. In the early 20th century, they were also known as sun cheaters.

<span class="mw-page-title-main">Thin-film optics</span> Branch of optics that deals with very thin structured layers of different materials

Thin-film optics is the branch of optics that deals with very thin structured layers of different materials. In order to exhibit thin-film optics, the thickness of the layers of material must be similar to the coherence length; for visible light it is most often observed between 200 and 1000 nm of thickness. Layers at this scale can have remarkable reflective properties due to light wave interference and the difference in refractive index between the layers, the air, and the substrate. These effects alter the way the optic reflects and transmits light. This effect, known as thin-film interference, is observable in soap bubbles and oil slicks.

<span class="mw-page-title-main">Ray-Ban</span> Eyewear company

Ray-Ban is a brand of luxury sunglasses and eyeglasses created in 1936 by Bausch & Lomb. The brand is best known for its Wayfarer and Aviator lines of sunglasses. In 1999, Bausch & Lomb sold the brand to Italian eyewear conglomerate Luxottica Group for a reported $640 million.

<span class="mw-page-title-main">Optical coating</span> Material which alters light reflection or transmission on optics

An optical coating is one or more thin layers of material deposited on an optical component such as a lens, prism or mirror, which alters the way in which the optic reflects and transmits light. These coatings have become a key technology in the field of optics. One type of optical coating is an anti-reflective coating, which reduces unwanted reflections from surfaces, and is commonly used on spectacle and camera lenses. Another type is the high-reflector coating, which can be used to produce mirrors that reflect greater than 99.99% of the light that falls on them. More complex optical coatings exhibit high reflection over some range of wavelengths, and anti-reflection over another range, allowing the production of dichroic thin-film filters.

<span class="mw-page-title-main">Goggles</span> Forms of protective eyewear that do not enclose the nose

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, and in swimming. Goggles are often worn when using power tools such as drills or chainsaws to prevent flying particles from damaging the eyes. Many types of goggles are available as prescription goggles for those with vision problems.

A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films is a fundamental step in many applications. A familiar example is the household mirror, which typically has a thin metal coating on the back of a sheet of glass to form a reflective interface. The process of silvering was once commonly used to produce mirrors, while more recently the metal layer is deposited using techniques such as sputtering. Advances in thin film deposition techniques during the 20th century have enabled a wide range of technological breakthroughs in areas such as magnetic recording media, electronic semiconductor devices, integrated passive devices, LEDs, optical coatings, hard coatings on cutting tools, and for both energy generation and storage. It is also being applied to pharmaceuticals, via thin-film drug delivery. A stack of thin films is called a multilayer.

<span class="mw-page-title-main">Anti-reflective coating</span> Optical coating that reduces reflection

An antireflective, antiglare or anti-reflection (AR) coating is a type of optical coating applied to the surface of lenses, other optical elements, and photovoltaic cells to reduce reflection. In typical imaging systems, this improves the efficiency since less light is lost due to reflection. In complex systems such as cameras, binoculars, telescopes, and microscopes the reduction in reflections also improves the contrast of the image by elimination of stray light. This is especially important in planetary astronomy. In other applications, the primary benefit is the elimination of the reflection itself, such as a coating on eyeglass lenses that makes the eyes of the wearer more visible to others, or a coating to reduce the glint from a covert viewer's binoculars or telescopic sight.

<span class="mw-page-title-main">Eye protection</span> Protective gear for the eyes

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 spray or impact from some type of ball or puck used in sports.

<span class="mw-page-title-main">Silvering</span> Silvering in mirrors

Silvering is the chemical process of coating a non-conductive substrate such as glass with a reflective substance, to produce a mirror. While the metal is often silver, the term is used for the application of any reflective metal.

<span class="mw-page-title-main">Dielectric mirror</span> Mirror made of dielectric materials

A dielectric mirror, also known as a Bragg mirror, is a type of mirror composed of multiple thin layers of dielectric material, typically deposited on a substrate of glass or some other optical material. By careful choice of the type and thickness of the dielectric layers, one can design an optical coating with specified reflectivity at different wavelengths of light. Dielectric mirrors are also used to produce ultra-high reflectivity mirrors: values of 99.999% or better over a narrow range of wavelengths can be produced using special techniques. Alternatively, they can be made to reflect a broad spectrum of light, such as the entire visible range or the spectrum of the Ti-sapphire laser.

<span class="mw-page-title-main">Aviator sunglasses</span> Style of sunglasses

Aviator sunglasses are a style of sunglasses that was developed by a group of American firms. The original Bausch & Lomb design is now commercially marketed as Ray-Ban Aviators, although other manufacturers also produce aviator-style sunglasses.

<span class="mw-page-title-main">Eyewear</span> Items and accessories worn on or over the eyes

Eyewear is a term used to refer to all devices worn over both of a person's eyes, or occasionally a single eye, for one or more of a variety of purposes. Though historically used for vision improvement and correction, eyewear has also evolved into eye protection, for fashion and aesthetic purposes, and starting in the late 20th century, computers and virtual reality.

Anti-scratch coating is a type of protective coating or film applied to an object's surface for mitigation against scratches. Scratches are small surface-level cuts left on a surface following interaction with a sharper object. Anti-scratch coatings provide scratch resistances by containing tiny microscopic materials with scratch-resistant properties. Scratch resistance materials come in the form of additives, filters, and binders. Besides materials, scratch resistances is impacted by coating formation techniques. Scratch resistance is measured using the Scratch-hardness test. Commercially, anti-scratch coatings are used in the automotive, optical, photographic, and electronics industries, where resale and/or functionality is impaired by scratches. Anti-scratch coatings are of growing importance as traditional scratch resistance materials like metals and glass are replaced with low-scratch resistant plastics.

<span class="mw-page-title-main">Doggles</span> Goggles for dogs

Doggles are a commercial brand of eye protection for dogs in the form of tinted goggles designed and manufactured to fit the shape of a dog's head.

Ballistic eyewear is a form of glasses or goggles that protect from small projectiles and fragments. For the U.S. military, choices are listed on the Authorized Protective Eyewear List (APEL). Ballistic eyewear including examples that meet APEL requirements are commercially available for anyone who wishes to buy it. The history of protective eyewear goes back to 1880 and extends through to World War I and the present. There are three standards that are currently used to test the effectiveness of ballistic eyewear. These include a U.S. civilian standard, a U.S. military standard (MIL-PRF-31013), and a European standard.

<span class="mw-page-title-main">Smartglasses</span> Wearable computers glasses

Smartglasses or smart glasses are eye or head-worn wearable computers that offer useful capabilities to the user. Many smartglasses include displays that add information alongside or to what the wearer sees. Alternatively, smartglasses are sometimes defined as glasses that are able to change their optical properties, such as smart sunglasses that are programmed to change tint by electronic means. Alternatively, smartglasses are sometimes defined as glasses that include headphone functionality.

References

  1. "History of the development of polarized sunglasses". Mixonline. 2012-09-20. Retrieved 2021-04-18.
  2. Edwin H. Land.
  3. "History of the development of polarized sunglasses". Mixonline. 2012-09-20. Retrieved 2021-04-18.
  4. "Who Invented Sunglasses? - Sunglasses Inventor". www.glasseshistory.com. Retrieved 2021-04-18.
  5. "Ray Ban glasses during WW II | Model Kits Review" . Retrieved 2021-04-18.
  6. "Ray Ban glasses during WW II | Model Kits Review" . Retrieved 2021-04-18.
  7. Sterling, Bruce (November 2023). "Preface". Mirrorshades: The Cyberpunk Anthology (Free online and ebook ed.). Retrieved 15 December 2023. Mirrored sunglasses have been a Movement totem since the early days of '82. The reasons for this are not hard to grasp. By hiding the eyes, mirrorshades prevent the forces of normalcy from realizing that one is crazed and possibly dangerous. They are the symbol of the sunstaring visionary, the biker, the rocker, the policeman, and similar outlaws. Mirrorshades—preferably in chrome and matte black, the Movement's totem colors—appeared in story after story, as a kind of literary badge.
  8. Company, Sudo Null. "Sudo Null - Latest IT News". SudoNull. Retrieved 2021-04-18.