The Sunglasses

The Sunglasses History...The Roman emperor Nero liked to watch gladiator fights with emeralds. These, however, appear to have worked rather like mirrors. Flat panes of smoky quartz which offered no corrective powers but did protect the eyes from glare were used in China in the 12th century or possibly earlier. Contemporary documents describe the use of such crystals by judges in Chinese courts to conceal their facial expressions while questioning witnesses.James Ayscough began experimenting with tinted lenses in spectacles in the mid-18th century. These were not "sunglasses" as such; Ayscough believed blue- or green-tinted glass could correct for specific vision impairments. Protection from the sun's rays was not a concern of his.
Sunglasses In Modern developmentsIn the early 1900s, the use of sunglasses started to become more widespread, especially among the pioneering stars of silent movies. But early movie stars did not wear sunglasses as much to avoid being recognized than to protect their eyes from the harshly bright lighting of some early film studios, often taking their sunglasses off only when stepping in front of the camera to shoot a scene.Inexpensive mass-produced sunglasses were introduced to America by Sam Foster in 1929. Foster found a ready market on the beaches of Atlantic City, New Jersey, where he began selling sunglasses under the name Foster Grant from a Woolworth on the Boardwalk.
The Sunglasses first became polarized in 1936, when Edwin H. Land began experimenting with making lenses with his patented Polaroid filter. Oakley developed Thump (2004), sunglasses with built-in digital audio player. This design has been copied by a number of smaller companies.

Glasses style and Fashion

Glasses (sunglass) Style and Fashion male and female:

Onassis glasses, "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. While originally worn by Onassis in the 1960's, the glasses eventually became popular with younger American girls around the year 2003. Big sunglasses have maintained their popularity through 2007. They have also expanded their demographic reach to adult women throughout the world. Modern day celebrities use these to hide from paparazzi.
With Mirrorshades
Mirrorshades are sunglasses with a mirrored coating on the surface. Their popularity with police officers in the United States has earned them the nickname "cop shades". The two most popular styles for these are dual lenses set in metal frames (which are often confused with Aviators), and "Wraparound" (a single, smooth, semi-circular lense 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 nosepick). Wraparound sunglasses are also quite popular in the world of extreme sports (Out door activities).
Oversized sunglasses A girl wearing oversized sunglasses

Oversize sunglasses are often used for humorous purposes, and look like a pair of sunglasses that is extremely large for the face. They usually come in bright colors with colored lenses and can be purchased cheaply.
Oversized sunglasses now.Over recent years however, moderately oversized sunglasses have become a fashion trend. There are many variations, such as the 'Onassis', discussed below, and Dior white sunglasses.
Aviators Ray-Ban

This are sunglasses with an oversized teardrop-shaped lens and thin metal frames. This design first appeared in 1936 by Ray Ban for issue to U.S. military aviators. Their popularity with pilots, military and law enforcement personnel in the United States has never wavered. As a fashion statement, models of aviator sunglasses are often made in mirrored, colored, degregated, and wrap-around styles. In addition to pilots, Aviator-style sunglasses gained popularity with young people in the late 1960's and continued to be very popular through the 70's and early 80's. Aviators again became popular in the first decade of the 2000's, along with renewed interest in retro-fashion.
Wayfarers Sunglass

First introduced by Ray-Ban, the Wayfarer design popularized since the 1950s by Hollywood celebrities such as James Dean is thought to be the bestselling sunglasses design to date.
Teashades glasses

Or called John Lennon glasses or "Ozzy Glasses", were a type of Psychedelic art wire-rim sunglasses that were often worn, usually for purely aesthetic reasons, by members of the 60's drug counterculture, as well as by opponents of segregation. Rockstars such as Mick Jagger, John Lennon, Ozzy Osbourne, and Janis Joplin 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 1960's, they were often elaborated; lenses were elaborately colored, mirrored, and degregated, and often of excessively large size, and the wire earpieces were sometimes exaggerated. A uniquely-colored or darkened glass lens was usually preferred.

Glacier Glasses (out door activities)

Sunglasses with round lenses and leather blinders that protect the eyes by blocking the sun's rays around the edges of the lenses. Because they provide extra protection from bright sun and light reflected by snow and ice, they are often used when traveling across glaciers or snowfields.

Sunglass Frames

Sunglass Frames Sunglass eyeshield uses a nylon half-frame and interchangeable lenses Frames are generally made from plastic, nylon, a metal or metal alloy. Nylon frames are usually used in sports because they are light weight and flexible. They are able to bend slightly and return to their original shape instead of breaking when pressure is applied to them. This flex can also help the glasses grip better on the wearer's face.

Sunglasses with Metal frames are usually more rigid than nylon frames thus they can be more easily damaged when participating in sporty activities, but this is not to say that they cannot be used for such activities. Because metal frames are more rigid, some models have spring loaded hinges to help them grip the wearer's face better. The end of the ear pieces and the bridge over the nose can be textured or have a rubber or plastic material to hold better. The end of the ear pieces are usually curved so that they wrap around the ear; however, some models have straight ear pieces. Oakley, for example, has straight ear pieces on all their glasses.
The frames can be made to hold the lenses in several different ways. There are three common styles: full frame, half frame, and frameless. Full frame glasses have the frame go all around the lenses. Half frames go around only half the lens, typically the frames attach to the top of the lenses and on the side near the top. Frameless glasses have no frame around the lenses and the ear stems are attached directly to the lenses. There are two styles of frameless glasses: those that have a piece of frame material connecting the two lenses together, and those that are a single lens with ear stems on each side.
Sunglass for sports-oriented have interchangeable lens options. Lenses can be easily removed and swapped with a different lens, usually a different colored lens. The purpose of this is to allow the wearer to easily change lenses when light conditions or activities change. The reason for this is because the cost of a set of lenses is less than the cost of a separate pair of glasses and carrying extra lenses is less bulky than carrying multiple pairs of glasses. It also allows easy replacement of a set of lenses if they are damaged. The most common type of sunglasses with interchangeable lenses have a single lens or shield that covers both eyes. Styles that use two lenses also exist, but are less common.
Nose Bridge the SunGlass, allow support between the lens and the face. The nose bridges also prevent pressure marks caused by the weight of the lens or frame on the cheeks. People with large noses may need a low nose bridge on their sunglasses. People with medium noses may need a low or medium nose bridge. People with small noses may need sunglasses with high nose bridges to allow clearance.

Construction of Sunglass (lens)

Sunglass for men/women (lens):

Color of the Sunglass lens can vary by style, fashion, and purpose, but for general use, green, grey, yellow, or brown is recommended to avoid or minimize color distortion which would be dangerous when, for instance, driving a car. Gray lenses are considered neutral because they do not enhance contrast or distort colors. Sunglass with Brown and green lenses cause some minimal color distortion, but have contrast-enhancing properties. Red lenses are good for medium and lower light conditions because they are good at enhancing contrast but causes color distortion. Orange and yellow lenses have the best contrast enhancement at depth perception but cause color distortion. Yellow lenses are commonly used by golfers and shooters for its contrast enhancement and depth perception properties. Blue and purple lenses offer no real benefits and are mainly cosmetic.
Clear lenses are used typically to protect the eyes from impact, debris, dust, or chemicals. Some sunglasses with interchangeable lens have optional clear lenses to protect the eyes during low light or night time activities. Debates exist as to whether "blue blocking" or amber tinted lenses may have a protective effect. Blue blocking sunglasses typically also block some light of other colors to function well in full sunlight. Some low blue glasses are for use inside at night to avoid suppression of the sleep promoting hormone melatonin. They provide enough light so normal evening activities can continue.
Some modelshave polarized lenses (made from Polaroid or a similar material) to reduce glare caused by light reflected from polarizing surfaces such as water as well as by polarized diffuse sky radiation (skylight). This can be especially useful when fishing, as the ability to see beneath the surface of the water is crucial.

A mirrored coating can also be applied to the lens. This mirrored coating reflects some of the light when it hits the lens before it is transmitted through the lens making it useful in bright conditions. These mirrored coatings can be made any color by the manufacturer for styling and fashion purposes. The color of the mirrored surface is irrelevant to the color of the lens.
Any of the above features: color, polarization, gradation, and mirroring, can be combined into a set of lenses for a pair of sunglasses. With the introduction of office computing, ergonomists can recommend mildly tinted glasses for display operators to increase contrast. Corrective lenses can be darkened to serve the same purpose, or secondary clip-on dark lenses can be placed in front of the regular lenses. Flip-up glasses feature a dark lens that can be flipped up when not in use. Some lenses gradually darken with bright light and lighten in darkness; these are known as photochromic lenses.
Sunglass lenses are made from either glass or plastic. Plastic lenses are typically made from acrylic, polycarbonate, or CR-39. 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 than glass lenses, but are more prone to scratching. They do however, offer more resistance to shattering than glass. Polycarbonate lenses are the lightest, and are also almost shatterproof, making them good for impact protection. CR-39 lenses are the most common plastic lenses, due to their low weight, high scratch resistance, low transparency for ultraviolet and infrared radiation, and other advantageous properties. For sunglasses that also include vision correction, see also corrective lens.

Standart Of Sunglasses

There are 3 sunglass standards, US, Europe and Australia:

US sunglass Standart
The US standard is ANSI Z80.3-1972. According to the ANSI Z80.3-2001 standard, the compliable lens should have a UVB (280 to 315nm) transmittance of no more than one per cent and a UVA (315 to 380nm) transmittance of no more than 0.5 times of the visual light transmittance.

Europe sunglass Standart

The European standard is EN 1836:2005. The four ratings are 0 for insufficient UV protection, 1 for sufficient UV protection, 2 for good UV protection and 3 for full UV protection.

Australia sunglass Standart

The Australian Standard is AS 1067. The five sunglass ratings under this standard are based on the amount of light they absorb, 0 to 4, with “0” providing some protection from UV radiation and sunglare, and “4” a high level of protection.

Sunglasses comfort & Protection

Sunglasses (sun Glasses) for men and women

Sunglasses can improve visual comfort and visual clarity by protecting the eye from glare. Various types of disposable sunglasses are dispensed to patients after receiving mydriatic eye drops during eye examinations.

For Protection the eyes.

The Brand 'Oakley' sunglasses pass the ANSI Z87.1 requirements and offer UV protectionExcessive exposure to ultraviolet radiation/UV can cause short-term and long-term ocular problems such as photokeratitis, snow blindness, cataracts, pterygium, and various eye cancers. Medical experts often advise the public on the importance of wearing sunglasses to protect the eyes from UV. In the European Union, a CE mark identifies glasses fulfilling quality regulations. In the preparation for solar eclipses, health authorities often warn against looking at the sun through sunglasses alone.
There is no demonstrated correlation between high prices and increased UV protection. A 1995 study reported that "Expensive brands and polarizing sunglasses do not guarantee optimal UVA protection." Australian Competition and Consumer Commission has also reported that "Consumers cannot rely on price as an indicator of quality". One unscientific survey even found a $6.95 pair of generic glasses with slightly better protection than Salvatore Ferragamo shades.
More recently, High energy visible light (HEV) has been implicated as a cause of age-related macular degeneration, and some manufacturers design to block it. Sunglasses may be especially important for children, as their ocular lenses are thought to transmit far more HEV light than adults (lenses "yellow" with age).
Some sunglasses also pass ANSI Z87.1 requirements for basic impact and high impact protection. These are voluntary standards, so not all sunglasses comply, nor are manufacturers required to comply. In the basic impact test, a 1 in (2.54 cm) steel ball is dropped on the lens from 127 cm. In the high velocity test, a 1/4 in (6.35mm) steel ball is shot at the lens at 150 ft/s (45.72 m/s). In both tests, no part of the lens can touch the eye. Find best sunglasses for protection with Comfort and your Eyes see Visual clarity.