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A pair
of sunglasses seems so simple -- it's two pieces of tinted glass or plastic
in some sort of plastic or metal frame. How much simpler can something
get? It turns out that there are many different things that you can do
with two pieces of glass, and these things can have big effect on you
when you use the lenses. As you will see in this article, there really
are differences. There are four things that a good pair of sunglasses
should do for you:
Sunglasses
provide protection from ultraviolet rays in sunlight - UV light damages
the cornea and the retina. Good sunglasses can eliminate UV rays completely.
Sunglasses
provide protection from intense light - When the eye receives too much
light, it naturally closes the iris. Once it has closed the iris as far
as it can, the next step is squinting. If there is still too much light,
as there can be when sunlight is reflecting off of snow, the result is
damage to the retina. Good sunglasses can block light entering the eyes
by as much as 97% to avoid damage.
Sunglasses
provide protection from glare - Certain surfaces like water can reflect
a great deal of light, and the bright spots can be distracting or they
can hide objects. Good sunglasses can completely eliminate glare like
this using polarization.
Sunglasses
eliminate specific frequencies of light - Certain frequencies of light
can blur vision, and others can enhance contrast. Choosing the right color
for your sunglasses lets them work better in specific situations.
When
you buy a pair of cheap sunglasses, you often give up all of these benefits
and can even make things worse. For example, if your sunglasses offer
no UV protection, you increase your exposure to UV rays. The sunglasses
block some of the light, opening your iris to allow more light in. However,
this also lets more UV light in as well and increases the damage UV light
can cause to the retina.
So there
really is a difference. Buying the right pair of good sunglasses for the
conditions in which you use them gives you maximum protection and performance.
The biggest
problem with cheap sunglasses lies in the way the lenses are made. Inexpensive
sunglasses have lenses made of ordinary plastic with a thin tinted coating
on them. The key to finding the perfect pair of sunglasses lies in picking
the right features for your situation. Here are some of the most important
features to compare when you buy a pair of sunglasses:
- Lens material ·
Lens quality
- Lens darkness
- Special coatings
or features
- Frame and lens
design
- Frame material
- Brand recognition
Why we wear sunglasses
When you don those shades, you may be addressing one or more of these
concerns:
- Health
- Safety
- Performance
- Perception
- Fashion
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