About sunglasses - Gkboptical

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About Sunglasses Gkboptical.com
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. In the
early 20th century they were also known as sun
cheaters
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History of Sunglasses

• In prehistoric and historic time, Inuit people
  wore flattened walrus ivory "glasses," that came
  with narrow slits that block harmful rays of the
  sun .
• First Sunglass in History Which
• Protect the eyes from Snow.
• Inuit snow goggles function by reducing exposure
  to sunlight, not by reducing its intensity

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Modern developments

• In the early 1900s, the use of sunglasses started
  to become more widespread, especially among movie
  stars. 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 lamps that were needed
  due to the extremely slow speed film stocks used
• 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

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Functions of Sunglasses

• Visual clarity and comfort
• 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.
• 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.
• The glare is neutralized by blocking the vertical
  (magnetic) components of light.

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Functions of Sunglasses

• Protection of Eyes from many Factors
• 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
• 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.
• Sunglasses are especially important for children,
  as their ocular lenses are thought to transmit
  far more HEV light than adults

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Functions of Sunglasses

• 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 .
• Several standards for sunglasses allow a general
  classification of the UV protection .
• Manufacturers often indicate simply that the
  sunglasses meet the requirements of a specific
  standard rather than publish the exact figures .

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Functions of Sunglasses

• Further functions of sunglasses
• Sunglasses can also be used to hide emotions
  this can range from hiding blinking to hiding
  weeping and its resulting red eyes .
• Fashion trends can be another reason for wearing
  sunglasses, particularly designer sunglasses
• People may also wear sunglasses to hide an
  abnormal appearance of their eyes.
• Fashion trends can also draw on the "cool" image
  of sunglasses.
• Some lawbreakers have also been known to wear
  sunglasses during or after committing a crime as
  an aid to hiding their identities.

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Standards for sunglasses

• There are three major sunglass standards, which
  are popularly known mostly as a reference for
  sunglass protection from UV radiation
• The Australian Standard is AS/NZS 10672003
  Sunglasses and fashion spectacles. The five
  ratings for transmittance (filter) under this
  standard are based on the amount of absorbed
  light
• The European standard EN 18362005 has four
  transmittance ratings "0" for insufficient UV
  protection, "2" for sufficient UHV protection,
  "6" for good UHV protection
• The U.S. standard is ANSI Z80.3-2001, which
  includes three transmittance categories.
  According to the ANSI Z80.3-2001 standard

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Special use sunglasses

• Sunglasses in Sports - Sunglasses have to meet
  special requirements when worn for sports . Strap
  or other fixing is typically used to keep glasses
  in place during sporting activities, and they
  have a nose cushion . 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.
• 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.

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Special-use sunglasses

• 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. Sun
  protection is needed against much higher UV
  radiation and even against harmful infrared
  radiation, both within and outside the
  spacecraft. Within the spacecraft, astronauts
  wear sunglasses with darker lenses and a thin
  protective gold coating.
• During space walks, the visor of the astronauts'
  helmets, which also has a thin gold coating for
  extra protection, functions as strong sunglasses

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Type Of Sunglasses

• Aviator sunglasses - are a style of sunglasses
  that were developed by Bausch Lomb and branded
  as Ray-Ban. They are characterized by dark, often
  reflective lenses having an area two or three
  times the area of the eyeball, and very thin
  metal frames with double or triple bridge and
  bayonet earpieces or flexible cable temples that
  hook behind the ears.
• The original design featured G-15 tempered glass
  lenses, i.e., neutral gray, transmitting 20 of
  incoming light. The large lenses are not flat but
  slightly convex. The design attempts to cover the
  entire range of the human eye and prevent as much
  light as possible from entering the eye from any
  angle
• Aviator sunglasses, or "pilot's glasses", were
  originally developed in 1936 by Ray-Ban for
  pilots to protect their eyes while flying.

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Type Of Sunglasses

• 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.

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Type Of Sunglasses

• 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.
• Singer Elton John sometimes wore oversized
  sunglasses on stage in the mid-1970s as part of
  his Captain Fantastic act.
• In the early 21stcentury moderately oversized
  sunglasses had become a fashion trend. There are
  many variations, such as the "Onassis", discussed
  below, and Dior white sunglasses.

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Type Of Sunglasses

• Teashades - "Teashades" (sometimes also called
  "John Lennon glasses", "Round Metal", or,
  occasionally, "Granny Glasses") were a type of
  psychedelic art wire-rim sunglasses that were
  often worn, usually for purely aesthetic reasons,
  by members of the 1960s counterculture, as well
  as by opponents of segregation.
• Pop icons such as Mick Jagger, Roger Daltrey,
  John Lennon, Jerry Garcia, Boy George, Liam
  Gallagher and 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

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Type Of Sunglasses

• 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, Roy
  Orbison and other actors and singers. The
  original frames were black frames in many
  different colors were later introduced. There is
  always a silver piece on the corners as well.

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Type Of Sunglasses

• Wrap-around sunglasses - Wrap-arounds (sometimes
  also called "Yoko Ono glasses") 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.

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