A guide to choosing your lenses type when buying glasses online.

TYPES OF LENSES

You may have spent a lot of time choosing your next pair of glasses but what about the most
important part of your glasses – the lenses? While ordering your glasses online, you will come
across several terms to describe the type of lenses that you need. These are commonly known
as single vision, bifocal and varifocal/progressive lenses which are all available in different
coatings.

We have broken them down into different categories to make things simpler for you to
understand, and for you to choose what is best for your needs.

1. Single Vision Lenses

Single vision glasses are the most common type of prescription lenses. They contain a single
power over the whole lens and are commonly used, for example, by someone who needs
glasses for driving, for computer screen use or for reading only. It is possible that a person has
the same prescription (strength/power of the lenses) for both distance and near vision so they
can use the same single vision glasses for all activities. Should your prescription be different in
the distance and near, then you may opt for either bifocal or varifocal/progressive lenses,
both of which are commonly known as multifocal lenses.

2. Bifocal Lenses

This type of lens has two prescriptions incorporated – one for the distance which is found at the
top, and one for near vision which is found in a bottom segment area. There is a visible dividing
line or curve which separates the two.

3. Varifocal/Progressive lenses

Varifocal lenses correct vision at different working distances – from the far distance to an
intermediate distance to near reading distance. Unlike bifocals, they do not have a visible line to
separate the different segments. This allows the change in prescription to be more gradual and
as such, in appearance they look just the same as single vision lenses.

The distance vision segment on the lens is situated just in front of the pupil (the dark circular
opening in the centre of the eye) while the reading part at the bottom. Between the two
segments there is a middle area which is called the intermediate part. The latter provides you
clear vision for looking at objects at arm’s length distance, for example, your computer screen.