The vast majority of people over 40 have something in common with Benjamin Franklin: presbyopia. Presbyopia is the gradual loss of eyesight experienced in middle age as the lenses in the eyes become less flexible.
Presbyopia makes it hard to focus on objects up close. Glasses easily correct for that, but if you already wear glasses this means you have to juggle multiple pairs to see at different distances.
Franklin invented bifocals (or double spectacles, as he called them) more than 200 years ago by combining the lenses from two pairs of glasses. Today, there’s another option: progressive eyewear.
What Are Progressive Lenses?
There are two kinds of corrective lenses that can help presbyopia: bi- or trifocals and progressive lenses. Bifocals and trifocals are much the same as Franklin’s original model.
Progressive lenses are a modern alternative to bifocal and trifocal lenses. They have the same convenience of putting all your prescriptions in a single frame without some of the drawbacks of bifocals.
Bifocals and Trifocals
In bifocals, there are two prescriptions divided by a clear line. The top portion is for far distances and the bottom is for close-up or reading.
Trifocals are another option for people who have trouble seeing at multiple distances. Instead of two prescriptions, trifocals have three. Like bifocals, the line between each prescription is visible.
The abrupt division between different lens powers can be a tough adjustment. If your daily tasks involve frequently looking between various distances, this can even cause dizziness.
Another drawback to bifocals is the association with aging because most people who use bifocals are older. Some people are reluctant to use bifocals because they don’t want their age announced by their glasses.
Progressive lenses are another take on the bifocal concept. They transition gradually between prescriptions but without the visible line. The top of the lens is for long distances, getting stronger as you move down the lens.
Many people find progressive lenses easier to use because of the smooth transition. Without the visible line, you also can’t tell someone is wearing progressives just by looking at them.
Progressive lenses are more expensive than bifocals, so some people choose bifocals simply because of the price. For others, however, the benefits of progressive lenses make them worth the cost.
How Does Progressive Eyewear Work?
The primary reason for presbyopia is the natural deterioration of your eyes’ lenses. In younger eyes, the lens is flexible and easily adjusts to focus on different distances. As you age, the lens stiffens, which makes it harder to shift focus.
Progressive lenses shift the focus for you. The prescription at the top matches the focus your eyes use for long distances. The prescription at the bottom matches the focus for close distances, with a gradual transition in between.
These transitions are designed so that you can see effortlessly. This is useful for tasks like computer work, where you need to see at both intermediary and close distances.
Because there are several strengths per lens, your eyes have to learn which part of the lens to look through for different tasks. The best way to adjust is to wear the glasses consistently.
Adjusting to New Lenses
While you’re getting used to progressive lenses, you may need to adjust when you move your head versus when you move your eyes.
In general, you’ll need to move your head more than with regular lenses when looking from side to side. The edges of progressive lenses aren’t as clear as the center portions.
On the other hand, for close-up activities like reading, you’ll need to move your eyes down towards the bottom of the lenses rather than bending your head.
It may take a while for your eyes to adjust to progressive glasses. If you’re still having trouble after a few weeks of wearing them, you can make an appointment with your optometrist to have your lenses adjusted.
Progressive lenses have to fit a lot into a small space. Larger frames with more surface area for lenses can help you adapt to your new glasses.
When Do You Need Progressive Lenses?
The best way to find out if you need progressive lenses is to get a vision exam. You can discuss your prescription and vision needs with your optometrist to find the best type of corrective lenses for your lifestyle.
That said, most people who need progressive lenses are over 40 years old. If you are older than 40 and have trouble seeing objects close to you, it may be time to try progressive lenses.
There are other reasons to use progressive lenses, however. They can be helpful for young children and people with astigmatism.
Nearsighted children who have difficulty focusing on objects that are close to them can use progressive lenses to help train their eyes. The progressive lenses help their eyes learn how to focus on their own, which can prevent or slow down vision loss.
People of all ages with astigmatism can also benefit from progressive lenses. Astigmatism is a vision problem caused by an irregularly shaped cornea or lens. Progressive lenses can be shaped to help correct this problem.
How to Get Progressive Eyewear
You can get progressive glasses from most glasses retailers. Whether this is your first or fiftieth pair of glasses, you will need to have a vision exam and get a prescription to get progressive lenses.
If you’re in the Houston, Texas area, make an appointment today to talk to an optometrist and see if progressive eyewear is right for you.