Many people don’t know that contact lenses don’t have to be a single prescription. In fact, there is a wide range of different contact lenses including bifocal and multifocal lenses. Not only that, but these lens types are usually also available in a variety of different lens types, including silicone hydrogel, soft, rigid gas permeable, long-wear, and daily contacts.
If you’ve not had more than one prescription incorporated into your eyewear before, but you’ve now been told that you would benefit from multiple lens powers to help you see at different distances, you’ll need to decide whether bifocal or multifocal lenses are right for you. To do this, it helps to understand why they are needed and the differences between them.
Most people who are recommended to have bifocal or multifocal lenses are diagnosed with presbyopia. This age-related refractive eye condition can occur alongside near or far-sightedness and happens when the natural lens of the eye starts to become harder and less flexible. As a result, patients are less able to focus on things nearby. In fact, presbyopia is a leading reason why many people over the age of 40 need to rely on reading glasses. However, since it can occur alongside near or far-sightedness, it means that those with it need several different prescriptions to be able to see clearly. This is where options like bifocal and multifocal lenses become extremely valuable.
Bifocals are glasses or contact lenses that have two different prescriptions incorporated into each lens. The upper portion of the lens contains your distance vision prescription. This is because we most often look up when we are looking at objects that are at a distance. This means that when you need to look at things like road signs, you’ll have to remember to use the top part of your vision.
The lower half of each lens contains the prescription that you need to help you to see nearby objects clearly, such as a book or smartphone screen. This is because when we are reading, we naturally focus our eyes downwards. This means that if you want to focus on nearby objects, you’ll need to make sure you look down and through the bottom half of your lenses.
The two different ‘zones’ of prescription in bifocals are very clear, with a distinct line that separates the two. There is no progression of change. This makes them very different from multifocal contact lenses that offer a much more gradual progression between prescriptions.
Multifocal lenses offer patients multiple corrective powers too, but they can incorporate three different varieties rather than just two. This makes them effective for near, far, and intermediate vision. This triple correction enables them to provide a much smoother and more gradual progression across the lens and there are no lines to separate the different sections.
The top third will help you to see at distance clearly. The middle third will be set for intermediate distance, such as looking at a computer screen, and the bottom third for near vision. By incorporating all three prescriptions into a single lens, patients are able to see clearly in any given situation, without having to change their prescription eyewear.
If you would like to find out more about bifocal and multifocal contact lenses, please visit Miller Vision Center at our office in Norman, Oklahoma. Call (405) 389-4200 to schedule an appointment today.