Shooting
Glasses Lenses
Lenses
are basically a core component of shooting glasses, so let's
look at each one of these lens components or features in more
detail:
:
Lens
Material
A very important important feature
to consider. In today's market most shooting glasses lens
are made from three materials:
For shooting glasses, Polycarbonate is
the best lens material available on the market today. It
weights less than Crown Glass and has a higher impact resistance
rating. Polycarbonate is about the same weight as CR 39
plastic, but also has a higher impact resistance rating.
Crown Glass and CR 39 Plastic offer little or no UV protection,
while Polycarbonate, even in it's clear form, provides excellent
UV protection.
Polycarbonate
is a type of LEXAN® thermoplastic from G.E., and is
the same material used for bullet resistant glass in autos.
It's such a hard material that a special diamond grinding
wheel must be used to cut the lens. To form the lens itself,
the material is melted and then force injected into a special
mold. In comparison, Polycarbonate lenses are lighter, more
durable, more impact-resistant and more scratch-resistant
than any other lens material in today's market. Many law
enforcement and fire agencies are now making polycarbonate
lens standard issue on all protective eyewear. We strongly
suggest looking at polycarbonate lens for your shooting
glasses.
Beware
of lower end or less expensive brands of shooting glasses
that advertise the lens as being "impact resistant
plastic" or plastic lens marked as"high impact
resistance". We'd recommend that you make sure that
the lens are Polycarbonate as it is a far superior material
over other plastic compounds.
Lens
Impact Resistance
In light of the application, this
is probably the most important feature to be concerned with.
Lens color, fit, etc. are all important, but they become
a mute point if the lens won't properly protect the eye.
Impact resistance ratings are typically standardized through
agencies and groups like Occupational Safety & Health
Administration (OHSA), American National Standards Institute
(ANSI), and the U.S. Military. These standardized rating provide
the minimum recommended impact resistance for safety based
lens. Some rating information from each group:
We
suggest choosing shooting glasses with lens that meet or exceed
all three standards. If not all three, at least two. As your
eyes are so valuable, we wouldn't recommend taking a chance
with any less.
Lens
UV protection
Ultraviolet radiation (UV) refers
to the low frequency light waves produced by the sun. There
are three forms of UV rays: UVA, UVB, and UVC.
-
UVC
- The atmosphere filters UV-C, so it is not a real concern.
- UVA -
The cause of sun related drug reactions.
-
UVB - This type of UV is responsible for sunburn, prolonged
eye damage, and most forms of sun related skin cancers.
It can penetrate thin cloud layers and up to three feet
of water. This is the one that will do the greatest damage
to eyes.
To
provide adequate protection, look for shooting glasses that
absorb at least 99% of UV radiation. Choose shooting glasses
with one of the following labels:
-
"Blocks
99% or 100% of UV rays"
-
"UV
absorption up to 400nm"
-
"meets
ANSI UV requirements."
Any
shooting glasses lens rating less than 99% or 400nm probably
won't provide adequate UV protection. It should be noted
that even clear Polycarbonate lens will block or absorb
UV rays, so don't become focused on the tint as playing
a role in the level of protection. To learn more, take a
look at this interesting article on UV
damage from the EPA.
Lens
color
This really comes down to personal preferences.
Lens for shooting glasses today come in a wide range of colors
from dark gray or smoke to amber to purple. Some info on specific
colors:
-
Smoke,
Gray and Gray-Green tints - The most common type
of lens color. They are effective at blocking glare without
changing color perception, making them a good choice for
all-weather use. Gray is a neutral, or "true,"
color that allows the wearer to see all colors as they
are. Gray shooting lenses do not enhance the target, but
they are good in bright sunlight.
- Amber-Brown
lens tints - Especially good at blocking the
blue light commonly found in diffused light such as one
might experience on a cloudy day. Amber can improve both
contrast and depth perception, and is a good all-around
choice for shooting or hunting.
- Yellow
or Orange tints - Improve contrast and give a
sensation of heightened visual acuity. So-called "Driving"
lenses are usually amber or yellow-brown. Lenses in these
hues block haze and blue light and enhance the orange
color of the target. The brighter yellow the lens color
is, the better it is for use at night.
- Purple-Vermillion
tints - A light purple color, which is actually
a combination of a neutral gray and a vermilion, is good
for enhancing the orange of the target against a background
of tall trees. Vermilion itself is useful to highlight
conditions where there is poor background, such as trees,
and to enhance the target against the background. If you
haven't shot with purple or vermillion tint glasses, it
does take some getting use to.
Many
shooting glasses manufacturers are now offering glasses
with interchangeable lens. Some manufacturers are now offering
glasses packages that come standard with a set of 3 different
colored lens. We highly recommend that you take a look at
this option, as you'll be able to get a lens set of colors/tints
to meet the needs of most lighting and atmospheric conditions
encountered.
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