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Sunglasses: a very brief
history
In the beginning sunglasses
weren’t always used to
protect peoples eyes from
the sun. The history dates
back to ancient China and
Rome. It has been reported
that the Roman Emperor Nero
enjoyed watching gladiators
through polished gems. In
China, sunglasses were used
before the 12th century.
Sunglasses were first made
out of lenses that were made
from flat panes of smoky
quartz. Chinese judges used
such glasses to hide their
facial expressions when
interrogating witnesses.
Sunglasses didn’t undergo
any further changes until
about the eighteenth century
with the work of James
Ayscough. He experimented
with tinted lenses in
spectacles.
Sunglasses
then went the change into
the popular item they are
today when Sam Foster
introduced them to America
in 1929. These sunglasses
were designed to protect
people’s eyes from the sun.
In 1936 sunglasses became
polarized when Edwin Land
began using his panted
Polaroid filter when making
sunglasses. From this
original process comes what
we now as polarized sun
glasses. They have come a
long way from their Roman
and Chinese roots.
Why wear polarized sun
glasses?
When the sun shines on the
water or any other
reflective surface, the
reflected light becomes
polarized. This means that
most, although not all of
the light waves move in one
plane. You see, normal light
moves in many planes and
polarized lenses allow only
light in one plane to pass
through the lens. Therefore
much of the glare is
eliminated.
Although light from the sun
is not polarized, it can be
separated into two polarized
components that are
reflected and transmitted in
different amounts by the
surface of the water. In
most cases more of the
horizontal component will be
reflected than the vertical
component, thus partially
polarizing the reflected
light. In order to help
eliminate the glare a lens
that is vertically polarized
is used. The height of the
sun also affects the degree
of polarization. Basically,
the polarized sun glasses
worn by fishermen have
polarized filters to help
block the light reflected by
the waters surface allowing
them to be able to see under
the waters surface.
Will polarized sun
glasses eliminate all
reflected light?
Absolutely not. As we said
before, polarized sun
glasses eliminate selective
parts of the reflected
light, thus reducing glare.
Why wear polarized sun
glasses when fishing?
Certain surfaces, such as
water, can reflect a lot of
light, and the resulting
bright spots can be quite
distracting and even hide
objects (such as fish). A
good pair of sunglasses can
almost completely eliminate
this kind of glare using
polarization. Polarization
can occur either naturally
or artificially. An example
of natural polarization can
be seen any time you look at
a lake or river. The
reflected glare off of the
surface of the water is the
light that doesn’t make it
through the “filter” of the
water, and is the reason you
often cannot see anything
below the surface, even if
the water is crystal clear.
When light strikes the
surface of the water a lot
of horizontally polarized
light is the result.
Therefore you can’t see
anything but the glare on
the water. Polarized lenses
in sun glasses are fixed at
an angler that only allows
vertically polarized light
to enter allowing the angler
to see into the water
spotting fish and structure.
What’s the difference
between polarized sun
glasses and normal sun
glasses?
Basically, normal sun
glasses decrease the
intensity of all light that
passes through the lenses.
Polarized sun glasses
decrease the same light, but
they do it selectively.
Polarized sun glasses can
selectively eliminate the
reflection from the light
coming from the waters
surface.
At the end of the day,
polarized eyewear is great
for activities such as
fishing, volleyball,
boating, or even driving.
Basically anywhere light
bounces off of a surface and
back at the person. In an
activity such as fishing,
where you are required to
stare at the water for long
periods of time. If you
would like to see what
JRWfishing.com has to offer
you simply click on
polarized sun glasses
and check them all out.
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