Lenses
Modern lenses are high-tech products, made with the utmost precision
and using highly sophisticated production methods. A lens is characterised
not only by its power, but also by the type of correction it provides.
It is important to have your glasses tailored with the exact lenses
to suit your needs. Each lens is surfaced individually according
to the prescription and lifestyle of the wearer.
Single vision lenses
Single vision (SV) lenses have the same prescription over the
whole lens surface. As a rule, this prescription power is selected
to ensure that the wearer has clear vision at all distances.
The required focus adjustment for vision at different distances
is then performed by the eye.
With SV lenses for reading glasses or other specific applications,
the prescription is optimised to the required near distance
(usually 40cm); clear vision at far distance is not possible
with reading glasses.
Progressive Lenses
Anyone approaching their 50th birthday knows the problem: eyes
of a hawk for things far away, but near vision - reading for example
- becomes more difficult as the years go by. This phenomenon,
known as presbyopia, affects spectacle wearers and non-spectacle
wearers alike and needs to be corrected with suitable lenses to
ensure good, stress-free vision.
The special surface design of progressive lenses provides continuous
sharp vision at all distances without having to switch glasses
all the time. Progressive lenses can now be fitted to small frames.
As some people find it difficult to adjust to progressive lenses,
there are multi-focal lens options available.
Multifocal lenses
In multifocal lenses, the different power zones are visibly separated
from one another. Lenses with one zone for distance vision and
one for near vision are known as bifocals; lenses with an additional
intermediate zone for vision at medium distances as trifocals.
Occupational Reader / Web Lens
Due to the increasing number of us working in front of computer
screens, a new lens type has been developed to meet the needs
of people needing crisp, clear vision beyond arms length (but
not distance). This mid-range lens has been titled an occupational
reader, designed for the growing number of people that require
a separate pair of glasses specifically for work.
Photochromic Lenses
Changing light conditions can be a source of vision stress, particularly
for those people who are sensitive to glare, and often suffer
from watery or red eyes or even tension headaches when the sun
is low in the sky or under diffused lighting. A simple way to
prevent these symptoms and to increase vision comfort is with
photochromic lenses. These 'intelligent' lenses allow relaxed
vision and good looks in every situation thanks to their variable
tint - light in the shade and indoors, but pleasantly dark in
the sun.
Glass or Plastic?
Spectacles are also known as glasses because the lenses used
to be made only of glass. This is no longer true today. Innovative
plastic materials are becoming more and more important in optics
and are increasingly displacing traditional mineral glass.
The reasons for this can be found in the clear product benefits
offered by plastic lenses. They are not only up to 100 times more
break resistant than glass lenses, they are also around 50% lighter.
In addition, they can be tinted in practically any colour.
New high-tech coatings make plastic lenses just as suitable for
everyday wear as lenses in glass. All these features make plastic
the material of the future for the development and production
of innovative lenses.
Extra Features
When considering new glasses, there are a number of ways to adapt
your lenses to your individual vision needs. There are several
extra features available that add more vision comfort, safety
and service life to your lenses. These include anti-reflective
coatings with integrated hard coatings or the selection of a fixed
or variable tint as comfortable light protection.
Anti-reflection coating
Over 90% of Matthews patients are realising the benefits of
an anti-reflective coating. Like all polished, transparent glass
surfaces, lenses also reflect some light before it enters or
exits the lens, creating unattractive reflections.
To produce the anti-reflection effect, a layer system consisting
of multiple single films is deposited on the lens surface. The
number of layers depends on the desired anti-reflection effect.
These incredibly thin anti-reflection films substantially reduce
irritating light reflections and so provide better vision and
looks under any light conditions.
Hard coating
Hard coatings are also frequently applied to plastic lenses
in addition to the anti-reflection films. Although plastic lenses
are pleasant to wear due to their low weight, they are much
more sensitive to scratching than glass. Specialised hard coats
make plastic lenses almost as scratch-resistant and durable
as glass lenses.
For advice on which type of lens is best for you contact
your nearest Matthews branch and make an appointment.
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