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FAQ about Sunglasses Part I
When I go outdoors, the sun doesn’t bother my eyes. Should I still wear sunglasses?
Yes. The rays of the sun contain harmful invisible UV light
that can cause severe and permanent
retinal damage. You need your vision to
last a lifetime. Don’t take chances, wear shades. Read
more facts about sunglasses and your eyesight.
I’ve heard a lot about Ultra Violet light. What exactly are
UV rays?
Ultraviolet (UV) light is electromagnetic radiation with a
wavelength shorter than that of visible light.
It gets its name because the
spectrum consists of electromagnetic waves with frequencies higher than
those
that humans can see and identify as the color violet (purple). A major source
of these invisible
UV rays is the sun. UV
light is composed of three different types: UVA, UVB and UVC. UVA has
the longest
wavelengths and can pass easily through glass. UVB rays are the most dangerous. High
intensities of UVB light exposure can cause photokeratitis or arc eye and can
even lead to cataracts.
UVB doesn't pass
through glass. UVC rays are filtered out by the atmosphere and typically do not
reach us. UVA, UVB and UVC can all
damage collagen fibers and thereby accelerate aging of the
skin.
Can UV rays affect my eyes?
If you ask most people they’ll say that their eyes are only
at risk when outdoors on a bright, sunny
day. The reality is that UV light easily
passes right through clouds on an overcast or dreary day.
You really need to protect your eyes from UV
rays all the time when outside especially if you are
near snow or water that
can easily reflect the sun’s rays. If you live high in the mountains you are
most at risk from UV rays due to the higher elevation.
Am I more at risk from UV rays if I have a pre-existing
medical problem?
Yes. If you have cataracts, macular degeneration, or damage
to the retina, you need to be
proactive and take preventive measures to protect
your eyesight from further deterioration.
What options do I have to prevent damage to my eyes?
The best way to prevent damage to your eyes is to always
wear sunglasses when outdoors. You
can get contact lenses that provide UV
protection but care should be taken as parts of your eye
remains exposed so you
should still wear sunglasses even with contact lenses. The sunglasses that
provide
the maximum protection have block from 99% to 100% of both UVA and UVB light. A
good choice of sunglasses is those lenses called UV 400 which block all of the UVA
and UVB rays.
Always insist on wraparound
sunglass design to prevent harmful UV rays from entering your eye
around the
frame.
What kind of lenses should I get?
A good choice for outdoorsmen like boaters, fishermen, hunters
and skiers is an amber colored
blue-blocker lense that eliminates blue
light. To reduce glare that is reflected
off of flat surfaces like
water or snow you need polarized lenses with an
anti-reflective coating. The ultimate in
limiting glare
are mirror coated lenses. Gradient or double gradient lenses
have varying tints from the top of the lens
down and/or from the bottom of the
lens up. Then there are photochromic
lenses that adjust to the environment based on the amount of exposure to UV
light, darker outdoors and light indoors or in
overcast conditions.
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