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Lens
Material |
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Hard Resin (plastic)
Conventional hard resin lenses
are half the weight of glass lenses and can be tinted to almost
any color and density. Hard resin lenses are more easily scratched
than glass but can have an optional scratch protection applied.
More impact resistant than glass, hard resin lenses do not require
tempering. |
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Lighter, Thinner Lenses
Modern technology has created
lenses that bend light differently so that stronger corrections
are thinner than when made in conventional materials. Such lenses
are called "high index" and stronger corrections are
more attractive because they are slimmer. Glass lenses are also
available with the slimming advantages of high index but are
considerably heavier. High index plastic uses less material so
they are often lighter in weight. High index lenses absorb all
harmful UV light and can be tinted to any shade or color. |
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Lenses That Darken in
the Sun
These are lenses that darken as
you go from indoors to outdoors. They are available in glass, hard
resin and polycarbonate. Originally made to darken to a moderate
shade, new versions are available that darken to a true sunglass.
Ask for a demonstration of these lenses. |
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Polycarbonate
Polycarbonate lenses are the
most impact resistant lenses available and are always the lens of
choice for young people and active patients. Polycarbonate lenses
are high index and usually provide the lightest, most comfortable
lenses. They absorb all harmful UV light and can be made ultra
thin because of their unique strength. |
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Glass
For years glass was the only
lens material available and glass still offers superior optics.
The most scratch-resistant material, the primary disadvantage of
glass is its weight, generally twice that of hard resin. Glass
lenses are heat or chemically tempered to increase impact
resistance. |
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Lens
Designs |
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Single Vision Lenses
Single vision lenses function
as all purpose glasses for persons who have normal accommodation.
Persons who normally wear bifocals or trifocals can use single
vision for distance or near glasses. Single vision lenses can also
function as occupational glasses for certain types of work. Single
vision lenses can be ordered in all materials. |
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Aspheric Lenses
These new lenses provide
special visual and cosmetic benefits for stronger corrections and
increase edge to edge clarity. Flatter than conventional lenses,
aspherics eliminate the "buggy" appearance of strong
plus lenses (far-sighted corrections) and improve the appearance
of finished eyewear. Near-sighted persons also benefit from
thinner, lighter weight glasses when the lenses are aspheric.
Aspheric lenses are positioned closer to the face so there is less
eye magnification with farsighted corrections and less "small
eyes" look with nearsighted corrections. Aspheric lenses can
be ordered in high index materials for the ultimate in attractive
thin lenses. |
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Flat Top Bifocals
This is the most common bifocal form and is available with the bifocal portion made in a
variety of widths to aid in various close-up occupations. Flat top
bifocals can be ordered in every type of lens material. |
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Trifocals
Trifocals come in a variety of
designs. Flat-top trifocals are the most widely used form. The
added segment provides clear vision at arm's length distance, that
middle area that is often blurred for bifocal wearers. Trifocals
can be ordered in all lens materials. |
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Progressives (no line
bifocals)
These modern lenses provide all
the benefits of bifocals but add the feature of continuous clear
vision at all distances, including mid-range distance (arm's
length). People like Progressives because they look like single
vision lenses, never revealing the need for bifocals. Progressives
are available in all lens materials and also made in aspheric
form. Because of all these advantages, they are becoming the lens
of choice for bifocal and trifocal wearers. |
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Occupational
Requirements
Many jobs impose demanding
visual requirements on people who wear bifocals or trifocals.
Special occupational designs are available to solve these special
needs. If the visual requirements of your job falls into this
category, let us know so we can determine what will work best for
your personal needs. |
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Sports Glasses
All sorts of special lens
designs are available for the special visual needs of sports
enthusiasts. Polycarbonate is usually the material of choice for
active sports. |
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Computer Glasses
There are a variety of special
lenses for computer users. These include special filters tints and
anti-reflection coatings. See also computer
glasses for more information. |
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Polarized Sun Lenses
These are the exciting
sunglasses that eliminate reflected glare. They are especially
appropriate for drivers, fisherman, hunters, and all types of
outdoors activities. |
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Optional
Lens Treatments |
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Scratch Protection
Coating
Light weight hard resin lenses
can be more easily scratched than glass lenses. Special coatings
have been developed to help protect lenses from normal scratching.
The modest additional cost for such scratch coating is usually a
prudent investment. Some of the newest lens materials include
scratch coating. |
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UV Protection
The ultraviolet rays found in
sunlight can pose potential harm to eyes. Special treatment is
available for hard resin lenses that completely blocks hazardous
UV light. Lenses like polycarbonate, high index and photochromatic
lenses include built-in UV protection at no extra cost. |
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Anti-Reflection Coatings
Special anti-reflective
coatings are now available for special lenses, much like those
used for fine camera lenses. These coatings are particularly
effective for reducing eye fatigue for computer operators and
anyone driving at night. And, of course, AR lenses enhance
appearance by removing all distracting reflections. |
