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202 Ophthalmic Lenses

Pink: Pink is the colour second least chosen but is an indication of low light
sensitivity. Migraine sufferors favour this colour for indoor. For outdoor
sun protection, second choice would be brown and green. It helps block
blue light thereby improving contrast and offers high contrast and are very
soothing to the eyes. It also improves road visibility. Many people feel that
pink lenses are more comfortable for long periods of time than other lenses.
They are great for computer users to reduce eyestrain and glare.
Fuchsia: This is often confused with pink but is actually from the shorter
wavelength end of the spectrum and is the part of the family of violet and
purple and is least chosen colour . Like blue it is favoured by light sensitive
because of its tendency to absorb all the higher wavelengths, but is too
dark even for the most light sensitive patients. Its contrast enhancing
properties are likely to be poor.
Grey: Grey is a neutral density filter which does not distort colour. Gray is
the general purpose tint because it tames bright sunlight. It is likely to be
favoured by the light sensitive and those who can not tolerate colour
distortion or whose job requires accurate colour discrimination as it absorbs
equally over the whole spectrum. It is not the contrast enhancer and is the
natural alternative to green in photo chromatic lenses. It is cosmetically
good for indoor use to reduce glare from fluorescent lamps, VDU and
television screen.
Polaroid lens: Polaroid lenses work similar to a Venetian blind by only letting
in light at certain angles. Without the sun’s glare, objects become more
distinct and are seen in their true colors. Reduced glare off water, roads,
and other objects make the polarized lens a favorite for water sports, fishing,
cycling and driving. The additional density of silver mirror front
complimented by back anti- reflection coating can be a great for sunny day
fishing. Polarized lenses may be appropriate for the recreational skier, but
as polarized lenses eliminate almost all reflected glare, they might pose a
hazard for the professional or more accomplished participant.These athletes
must be able to spot and respond quickly to ice and water patches.These
would be all but invisible with polarized lenses. A more effective choice
would be a mirror coating. Mirrors limit glare without eliminating it,
offering the contrasts needed. Mirrors also add to the overall absorption of
the lens.The denser the mirror coat, the more the absorption.

Photochromatic lenses: In changeable weather conditions or in sport where
you are moving from areas of bright light to shade (for example golf and
cycling) photochromic lenses are useful. These lenses darken in bright light
and become paler in less intense light conditions.