A presentation on sunglasses.

1. PRESENTED BY – AL AMIN
B.OPTOMETRY 2ND YEAR.
SUNGLASSES

2. INTRODUCTION
Sunglasses or sun-glasses are a form
of protective eyewear designed primarily to
prevent bright or excessive 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.

3. HISTORY
 In the early 20th century, they were also known as sun
cheaters.
 Sunglasses have been around since pre historic period
from wood.
 Sunglasses were originally invented to reduce
distracting glare and allow more comfortable viewing
in bright light.
 Early sunglasses were simply tinted glass or plastic
lenses were primarily meant to reduce brightness.
 In 12th century, sunglasses appeared in China, made
from thin slices of polished grey quartz.
 In 18th century, James Ayscough experimented with
blue and green tinted spectacles to correct vision
impairments.

4.  In 1929, Sam Foster launches cheap sunglasses that
provided protection against UV rays.
 In 1936, Bausch & Lomb launched developed Aviators
for pilots under the name Ray Ban.
 In 1937, Edvin Land lends his polarizing photography to
Bausch & Lomb to produce glasses that significantly
reduce glare.
 In 1952, Ray Ban released Wayfer, took the market
by storm and were the first to employ plactic only
frame.
 In 1980s, Shutter shades designed by Alain Mikli
gained immense popularity after featuring in music
videos.
 In 1988, Nitinol launched made from Nickel-Titanium
alloy.
 In 1996,The Sunglass Outlet by Christopher Lord and
Pamela Lord is launched. It offers the best sunglass
selection on the cutting edge of fashion. It is premium
place of designer inspired sunglasses at affordable
prices.

5. WAYFER BY RAY-BAN

6. RAW MATERIALS
 Sunglasses consist of a pair of light-filtering lenses and a frame
to hold them in place.
 Majority of lenses are made of colorized plastic such as
polycarbonate.
 The glass used in lenses is scratch resistant and is made impact
resistant by tempering it with various chemical treatment.
 Soluble organic dyes and metallic oxide pigments are added to
lens material to absorb or reflect light of certain frequencies.
 Frames are made from metal or plastic. Metal frames are
expensive ones, are often made of mixtures of nickel and other
metals such as silver.
 These frames have sculpted and gimbaled nose-pads, durable
hinges with self-locking screws, and flexible temples.
 Manufacturers use combinations of nickel, silver, stainless
steel, graphite and nylon in their leading-edge designs.

7. DESIGNS
 Fashion and function are two key elements to consider
sunglsses design.
 There are sunglasses for clothing designers, fragnance
marketers and sporting goods vendors custom design.
 Some designs are considered “classic” and timeless,
other must be continually updated to satisfy the
public’s constantly changing taste.
 Sports enthusiasts have specific requirements that are
reflected in sunglass design.
 Sunglass also protect the eyes by either absorbing or
reflecting cetain frequescies of light.
 This range of frequency can be controlled by changing
the mixture of colorizing additives.

8. LENS
 Light actually consists of two waves, one propagated
in the horizontal plane and one in the vertical plane.
 Polarized lenses are made using a special optical filter
which absorbs the horizontal component of light and
transmits only the vertical component as a result eye
strain is reduced.
 Some Polarized lenses do not block UV light, so they
require additional coatings or coloring agents to
provide complete eye protection.
 The photochromatic lens contains silver salts like those
used in photographic film.
 These lenses darken outdoors and lighten indoors. In
this way colour changes in response to UV exposure.

9. MANUFACTURING PROCESS
 LENSES
1. Coherent is added to lenses in two primary ways,
either by adding colour to molten lens material before
the lens is formed, or by chemically post-coating the
finished lens to achieve the desired hue.The colorant
additives are incorporated into the lens while the
plastic or glass is at high temp. And still liquefied.
Soluble organic dyes or matallic oxide pigments are
added to plastic. Metallic oxide or metal particles are
incorporated into glass.
2. After the appropriate additives have been blended in,
the molten plastic or glass is then cast nto the general
lens shape or “puck”. Inexpensive lenses are simple
pucks that placed into frames. Expensive lenses are
prepared in a manner similar to the method by which
prescription lenses are made. First the appropriate lens
puck is placed in a lensometer.

10. 3.The lens is then put in a curve generator, which grinds
out the back of the lens according to the patient’s
prescription. An edge grinder then grinds the outer rim
to its proper shape and puts a bevel on the edge,
allowing the lens to fit properly on the frames.
4. Lenses may now be coated with an anti-reflective
material.The post-caoting method produces lenses
that are more evenly coated regardless of the lens
configuration. It also allows for the coating to be
removed and recoated after the lens is made. Such
coating may be applied through a vaccum coating
method, used to deposit an anti-reflective layer on the
lens surface to reduce internal reflections.This faint
bluish coating is also commonly used on camera lenses
and binoculars.

11.  FRAMES
5. The finished lenses are now ready to be mounted
in eyeglass frames. Frames are constructed to hold
the lenses in place using either a tension mount or
screw mount design.Tension mounting is typically
used in plastic frames. In this type of frame, the
dimension of the lens opening on the front surface
of the frame are somewhat smaller than the lens
itself. In this way the lenses can be pressed into
their respective openings through the front edge
of the frame without falling out its rear edge. A
groove is formed in the periphery of each of the
openings, and these mate with a ridge formed on
the periphery of the respective left and right
lenses.The plastic frame material permits
sufficient stretching or elongation to allow the
lenses to snap into these grooves.

12. 6. Metal frames use a screw mount design because metal
tends to deform easily and cannot hold the lenses as
well.The metal structure of the frames has thin
extruded sections that are bent into desired shapes.
The frame structure surrounding the lens opening
forms an open loop into which the lens is inserted, the
loop is closed by attaching a screw to the two open
ends.

13. REGULATIONS
There is governmental regulations of sunglasses.
Labeling of absorbance rates of both types of UV
light, UVA and UVB but the American National
Standards Institute(ANSI) has established
transmittance guidelines of general purpose and
special lenses. According to thse standards,
general purpose cosmetic lenses must block 70%
of UVB, general purpose must block 95% of UVB
and most UVA light. Special purpose must block
99% of UVB.

14. QUALITY
Inexpensive plastic models have little concern with optical
perfection, they may contain flaws which will distort the
wearer’s vision. On the other hand, expensive glasses
lenses strive for high optical quality and are checked
accordingly.
One of the simplest test to evaluate distortion of
the finished lens is to simply hold the glasses at arms
length and look at straight line in the distance. Slowly
move the lenses across the line. If the lens causes the line
to sway or bend, the lenses are optically imperfect. We
can look through the outer edges of the lens as well as
centre.
Moreover no such waste is produced except the
plastic,glass and metallic scrap from grinding the lenses
sand making the frames.

15. BRANDS
1. Ray-Ban - Ray-Ban brand of sunglasses and eyeglasses is
the most famous brand and known forAviator lines of
sunglasses, Part of the Italian eyewear Luxottica Group.
2. Fastrack - Fastrack is the brand ofTitan Watches and one
of the most growing fashion accessory brand in India,
offering best budget sunglasses for women and men in India
from black, brown, grey & more colours.
3.IDEE - IDEE brand of eyewear have set the standards in
eyewear market of India with iconic product range,
trendsetter and high quality variety of glass.
4. Polaroid - Polaroid eyewear is an Italian luxury eyewear
brand that manufactures polarized sunglasses and lenses.
Sunglasses from Polarized offers excellent quality, shades
and a collection of super trendy style.
There are more brands likeVogue, Police, Prada, Oakley,
Gucci etc…

16. PRODUCTIONAND FUTURE
 In response to increasing demand for high quality,
stylish glasses manufacturing process have becoming
increasingly sophisticated.
 New improvements in manufacturing the frames.
 New coatings and colorants which deliver better
protection against UV radiation continue to develop.
 Keeping in mind the field of optics, surface chemistry,
metallurgy and others new high performance sun-
protective eyewear are introduced.

17. FACTS
 80% of the damage to the eyes occurs before we are
18yrs old.
 5-10% of skin cancer occurs on the eye lids.
 19% of people wear contact lenses.
 94% do not know that UV rays cause damage to the
eyes and hence don’t check UV rating before wearing.
 53% mistankenly believe that sunglasses with darker
shades provide better UV protection.
 68% with light coloured eyes don’t know about being
prone to UV related damage.
 UV rays damage the eyes and can also cause skin
cancer, sunglasses should block 98-99% 0f UV rays.

18. HEALTH BENIFITS
 Protect eyes from UV.
 Decrease dry eye problem.
 Less squinting.
 Reduced strain.
 No ditortion in colours.
 Power glass correct blurred vision.
 Preventation from cataract.

19. END OF SLIDES. THANK YOU