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Progressive
lenses or "blended" lenses are designed to
give clear vision for viewing objects at any distance.
As you reach your mid forties you will notice that your
reading vision isn't as clear as it used to be. For
those who have never worn glasses and don't need a prescription
to see clearly at distance simple over-the-counter "readers"
may work fine. Near-sighted (myopic) people may be able
to just take their distance glasses off and see fine
up close. Far-sighted (hyperopic) folks need even more
help up close and they seem to need bifocal or progressive
lenses at an earlier age than those who have perfect
distance vision or those who are near-sighted!
Prior
to the invention of progressive lenses people wore bifocals
or trifocals (the lenses with lines in them)when they
reached the "magic" age. These lenses work
fine for most tasks except computer work.
Computer screens have a working distance of about 26
inches on average. This is a little too far for the
bottom part of a bifocal and too close for the top distance
portion of the lens. Fortunately, progressive lenses
have an area in them just right for the computer working
distance.
It
takes a bit of adjustment to become comfortable with
using progressive lenses but most people do adapt with
time. However, I have found that people who have excellent
near or distance vision without correction have
a more difficult time adapting to these lenses. Also,
if a person has never worn spectacles before at all,
they may also have a more challenging task in adapting.
I
looked in the catalog listing all the brands and models
of progressive lenses and there was 315 different lens
models! Some of them came in 5 different lens materials
so the total number of choices is amazing. Some models
are easier for first time users to adapt to. Some have
a wider intermediate zone which makes them even better
for computer use. Some have real short, fast blends
which work in the fashion frames that have small vertical
lens dimensions. Some have clearer, broader peripheral
vision. The goal is to pick the right lens for what
the visual requirements are for the person and the size
of the frame they choose. This takes a bit of practice
for the practitioner to learn as does learning how to
adjust the frame to fit comfortably and properly.
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Progressive Lenses
