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Ultra-Violet
(UV) radiation and damage to the eye »
» Photochromic lenses:
Photochromic lenses are designed to react to different light
conditions encountered during the day. They change colour
and become darker in response to increased exposure to ultraviolet
radiation (usually found in brighter light conditions),
thereby protecting your eyes from harmful UV rays and making
it easier to see in such conditions. In less bright (low
UV) light conditions, photochromic lenses remain lightly
tinted, enabling the wearer to see clearly.
High quality photochromic lenses adapt quickly to changing
light conditions and provide maximum protection against
UV radiation. Photochromic lenses offer flexibility to a
wearer of prescription glasses, and can be used indoors
and outdoors.
Photochromic lenses are available in glass or plastic, but
polycarbonate lenses are best and have the additional advantages of being much lighter
and shatter and scratch resistant.
Our opticians would be happy to assist you in assessing
whether you would benefit from changing to photochromic
lenses.
» Polarised lenses:
Polarised lenses are available in gray, brown and sometimes in gray-green (G15, Rayban lens color) and
may be used by both prescription and non-prescription wearers.
These lenses are designed to eliminate glare, which often
arises through the reflection of light on shiny or bright
surfaces such as water, snow, glass or metal.
Polarised lenses assist more comfortable vision by eliminating
glare and are suitable for many sports, such as
fishing, skiing and water sports.
» Ultra-Violet (UV) radiation and damage to the eye:
The skin and eyes are at risk from ultraviolet radiation
emitted from the sun. Ultraviolet radiation is below the
visible spectrum of radiation emitted by the dun and broadly
falls into three categories: UVA, UVB and UVC. UVC rays
are usually absorbed by the upper atmosphere, and the
harmful effects of radiation are therefore a result of
UVA and UVB radiation.
The effects of strong sunlight range from acute damage
to the front surface of the eye by UV rays, to the more
long-term effects of various wavelengths on the skin of
the eyelids and on the internal structures.
We would recommend that every one should take the following
easy steps to ensure they are fully protected from the effects
of direct exposure to sunshine:
- Always wear sunglasses outdoors.
Even if it is overcast or raining, UV radiation penetrates
the atmosphere and could cause damage to your skin and
eyes. Bear in mind that UV radiation levels are higher
in the following types of conditions, when greater protection
may be required:
- during summer,
- in the middle of the day,
-
on the beach or at sea where there
is little or no shade provided by trees or buildings,
-
at high altitude (e.g. when skiing).
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