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					How do binoculars work? We all know that binoculars bring far-away images up close.
Hunters and bird watchers rely on binoculars to bring their quarry into clear detail and
sports fans often bring binoculars to the event so they don't miss one moment of action. To
create those images, binoculars need to gather light and focus it into your eyes.

Binoculars work on the same principles as telescopes. The process begins with a series of
lenses. The lenses focus on an object and gather the light from it. As the light passes through
a series of lenses, the image gets larger. Binoculars differ from a telescope in that they allow
the image to be transmitted to both eyes at once.

Binocular lenses are curved pieces of glass. A binocular can have several lenses; in fact, the
more lenses that the binocular has, the better the magnification. Unfortunately, each time
the image passes into the next lens, light is lost, so binoculars include a prism that bends and
reflects light into the lenses. The prism also flips the image. Without it, everything you see
through the lenses would be upside down.

All lenses have specific strengths of magnification, such as 7x or 10x. The strength rating
indicates that the image will appear 7 or 10 times closer to you. Binoculars also come in
zoom style, meaning that they have a varying range of magnification. Adjustable binoculars
with a 10-22x 50 rating have a minimum viewing of 10x that can be increased to 22 x
powers. The 50 indicates the size of the objective lens.

With binoculars, you look through eyepieces to bring the distant image into focus. The
eyepieces are the last lenses in the series. The first lenses in the series, mounted on the far
end of the binoculars, are referred to as the objective lenses. These do most of the
magnification work.

You customize the view through binoculars by adjusting the center focus wheel until the
image is in focus for your left eye. You then use the right eye diopter to focus for your right
eye. No two people will use the same settings on a binocular. Less-expensive, smaller
binoculars are often fixed-image binoculars that do not allow you to customize the focus.
This means the image will not be as clear, or that it will only be clear at certain distances.

For people who use binoculars for a long time, like hunters and bird watchers, there are
times when the image becomes blurry. This blurring is due to shaking, caused by wind,
muscle fatigue or excitement. To combat the blurring, image stabilization binoculars are
available. The image stabilization technology works by making instant adjustments to the
refraction angle of the binoculars, which compensates for motion. This means even if your
hands are shaking the image will remain steady.

Those who hunt at night, or just enjoy a neat toy, might want to try night vision binoculars.
Night vision binoculars use image-enhancement technology that magnifies tiny amounts of
light to make night time landscapes look as bright as day. The most common technology
used is infrared, which is a light wavelength that's invisible to the eye. Infrared lights
illuminate the image, and the reflected light is analyzed by a built-in computer and displayed
on small LCD screens in front of the eyepieces.

				
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posted:11/3/2011
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