Progressive lenses, also known as multifocals or varifocals, and sometimes "three layer can see far and near lenses", comes with both advantages and disadvantages for the wearer, which we will explore in this post.
Presbyopia is a condition whereby the eye loses the ability to focus at near. This usually sets in at about 40 years old, with the presbyopic power increasing slowly in the next two decades or so. This cannot be reversed, and is a natural phenomenon.
In some situations, such as when the wearer's current myopic prescription is overcorrected, presbyopic symptoms can present earlier, i.e. before 40 years old, although this can be easily resolved by reducing the myopic prescription to the appropriate power.
You can read more about presbyopia and progressive lenses here.
Advantage 1 - Convenience
With progressive lenses, you can go from distant to near vision in a split second. No more taking out your reading glasses to reply a text, or changing into distant glasses when standing up from your desk. You only need to use the appropriate zones within the progressive lenses to switch between seeing far and near.
Advantage 2 - Comfort over Bifocals
Unlike bifocals that have a prescription 'jump' from the distance power to the near power, the presbyopic (reading) power gradually increases towards the bottom of the lenses, resulting in a smooth transition from the distance portion to the near portion of the lenses.
Advantage 3 - Aesthetics
Unlike the older bifocals or trifocals, progressive lenses seamlessly blend in the presbyopic (reading) power, which means the absence of a line or lines. This is more aesthetically appealing, which is a plus point for many wearers, who may not like to be seen as requiring a presbyopic power or reading glasses.
Advantage 4 - You have all the Powers
Since the presbyopic (reading) power comes in as you look from the top to the bottom of the lenses, with the maximum presbyopic power right at the bottom, this means you actually have lesser (and varying) amounts of presbyopia in between the distance and near zones on the lenses. These intermediate powers can be used for viewing objects that are at intermediate distance, e.g. at the hotpot in the centre of the dining table. Nom nom.
Disadvantage 1 - Learning and Adaptation
Like learning how to ride a bicycle, we don't immediately get the hang of progressives. This is why it is important to control your expectations (it's not a "magic pill") and fully understand how progressives and the different zones within the progressives work. When dispensing progressive lenses, even for more experienced users, we like to ensure that the wearer knows how to use the lenses appropriately, and to take a little bit of time to walk and look around to adapt to the lenses.
Disadvantage 2 - Smaller Usable Areas
While you have various zones that you are able to use for objects at different distances, having multiple zones also means that each zone is smaller. Hence, for prolonged work at a certain distance, e.g. if you need to be on the laptop for hours on end, you may find that having a single vision lens (reading glasses in this case) is more comfortable as it will allow you to have more flexibility in head and eye positioning and hence your posture.
Disadvantage 3 - Price
Progressive lenses are relatively more expensive than single vision lenses, although with the popularity in recent times the prices have fallen to where it has become attractive enough for many users to want to give it a try, even for those who previously were concerned about adapting to progressive lenses. The cost of progressive spectacles these days is approximately the cost of doing two or three pairs of single vision glasses - minus the inconvenience of carrying two pairs of glasses around!
Disadvantage 4 - Sensitivity and Perfection
Progressive lenses may be more sensitive to frame fitting, i.e. how the frame sits on your face. This is a potential issue if you abuse your glasses, since a frame that is out of shape will mean that the zones are in different positions than intended. So stop frame abuse today; use both hands to remove your glasses! Also, with multiple powers within the lenses, we never believe things can be 100% perfect, no matter what the advertisements say; so if you're a perfectionist, you might want to proceed with caution.
With the above pros and cons, you may realise that progressive lenses may not be as straight-foward as we would expect it to be, both for the wearer as well as the eyecare practitioner fitting the lenses.
It is important to know more about the lifestyle of the user and how the lenses will be used, i.e. the environment of the user. We tend to also try gather information about the motivation or reason for progressives, or for some users, the reasons behind why they feel uncomfortable with their current progressive glasses.
Through this, we are able to suggest a suitable solution for the spectacles wearer - and don't be surprised, sometimes the solution may be to not use progressives at all. Indeed we have advised a handful of customers that the ideal solution for them is to have two pairs of glasses, one for far and one for reading, which would best suit their needs.
There are also various other alternatives, like having both a progressive glasses as well as a reading or driving glasses, or the use of office lenses that is for use within the office cubicle - giving relatively excellent intermediate and near vision as compared to a conventional progressive lens.
We wrote a post about some cases where progressive lenses fail. If you are looking for alternatives beacuse progressive lenses don't seem not to work for you, also check that article out.
Else, there's always Otago Optical to help you.