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1. H T T P : / / W W W . I R V I N E O P T O M E T R Y . N E T
Glare From Eyeglass Lenses?

2.  Ever noticed glare or reflection from someone’s
eyeglass lens? The person wearing these glasses and
lenses may not realize it, but 8% of light that hits a
person’s glasses induces annoying reflections and
glare. This reflection and glare causes not only vision
disturbance but also reduction in the person’s vision.

3.  Today there are special coatings that can be been
applied to eyeglass lenses that virtually eliminate all
reflection and glare. This is especially important with
indoor lighting, streetlights, headlights, television
and computer screens. With computer vision
syndrome being so prominent and common, the
need to eliminate glare on lenses is essential for
eyewear when it comes to looking at a computer
screen all day.

4.  The type of coating that is applied to eyeglasses to
stop the reflection and glare is something that is
referred to as A/R, anti-reflection or antireflective
coatings. The Anti-Reflection coating is applied to
the surface of lenses and other optical devices. The
anti-reflective coating consists of a transparent thin
film which contrasts the refractive index. The thin
film layer helps change the wavelength and incident
angle of the incoming light.

5.  The Anti-Reflective coating and interference based
coatings were invented by Alexander Smakula in
1935. Alexander Smakula was working for the Carl
Zeiss optics company at the time. The German
military actually used the Anti-reflection coatings as
a military secret during World War II. It wasn’t until
1930 though that Katharine Burr Blodgett and Irving
Langmuir developed the organic anti-reflection
coatings.

6.  This improves the efficiency of the eyeglass lenses
since less of the incoming light is lost. The reduction
of the glare and reflections helps improve the
contrast of the image one is looking at. By adding the
A/R coating one can reduce the stray light in the
lenses.

7.  When one applies the coating to a new pair of
eyeglasses, this helps enhance eye contact. Another
benefit to the anti-glare treatment is the fact it
enhances the appearance of your eyewear. Besides
the benefits of the anti-glare coating, most A/R
coatings include additional coatings that repel water
and grease. This makes the lenses very easy to keep
clean. The A/R coatings are usually suited towards
higher-indexed lenses as they tend to reflect more
light. It usually is cheaper to coat higher indexed
lenses than that of low index glasses.

8.  The thin film anti-reflective coatings help to greatly
reduce the loss of light in the many elements of the
lenses. The quarter-wavelength of coating can
eliminate all reflection in the eyeglass lens.