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There are lots of contact lens manufacturers and they use different
names for the same things. Here’s a quick jargon-buster to help you if
you’re new to contact lenses.
Contact Lenses by frequency of use
Contact lenses are often called daily contact lenses/dailies, weeklies,
bi-weeklies, monthlies or extended wear (EW). The vast majority of users
prefer daily lenses, because they minimise the amount of fuss around
cleaning routines – you simply throw them away at the end of the day.
Dailies, however, are more expensive. Also, it’s not however possible
for all users to get their prescriptions in daily format. Others prefer
the extended format – ideally, you would want to put your lenses in and
leave them in, taking them out only at the end of the month.
Contact Lenses by purpose
There are basically three types of lens, spherical lenses, toric lenses
and multifocal/varifocal lenses. Most users with short or far
sightedness will use spherical lenses. People with astigmatism will wear
toric lenses. Actually, there is quite a cross-over here. You may find
you have been on the borderline and could quite comfortably switch for a
trial period. Finally, for people who are starting to experience with
presbyopia, varifocal contact lenses do away with the need for an
additional pair of reading glasses.
Contact Lenses by materials
Originally contact lenses were made of glass. These were replaced by
PMMA (Plexiglas / Perspex) but due to the limited permeability of oxygen
they are very hard to find nowadays. They were in turn replaced by RGP
(rigid gas permeable) contact lenses. Generically, both PMMA and RGP are
referred to as “hard” lenses. Typically they have long (more than one
year) replacement schedules. Many people have been wearing these for
years when actually soft lenses may be more appropriate with the new
widely available technologies.
Further development resulted in “soft” lenses. They are in the first
place a great breakthrough in immediate comfort. RGP lenses tend to take
some getting used to but soft lenses are great from the moment you first
put them in. The other comfort advance has come with increased gas
permeability. The arrival of silicone hydrogels brings us right up to
date, resulting in optimal oxygen permeability and (by various
technologies) high moisture levels.
The most common silicone hydrogel brands are Cibavision Air Optix and
Night & Day, J&J's Acuvue Advance and Oasys and B&L's PureVision.
Contact Lenses by brand
Most people only understand their lens type in terms of their own brand
(although interestingly brand awareness is not that strong amongst
contact lens wearers). They therefore see themselves as Johnson &
Johnson (Acuvue), Bausch & Lomb, Ciba Vision or Coopervision users. Each
brand tends to use trademarked technologies which can obscure the basic
type of lens. Additionally, many optician chains have created their own
labels (all of which can be replaced with manufacturers’ products using
our equivalency tables) such as Boots Dailies.
Own-brand contact lenses
The high-street opticians supply generic or own-brand contact lenses.
These come out of the same factory as our lenses – it’s just that ours
are originally branded. You can read an article about own-brand lenses
here.
Own Brand Contact Lenses
Not found what you were looking for? Go back to our Help & Information Page.
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