Presbyopia, or far-sightedness, is a common condition that often starts to affect those over the age of 40. Fortunately, this doesn't mean that those who already wear prescription eyeglasses to tend to their problems with distance vision are required to own two pairs of glasses. Multifocal lenses, which rectify both myopia and presbyopia, let you see well at all times, with one pair of glasses.
Before mulifocals, bifocals were the obvious solution, but they weren't perfect; while they help you to focus on both near and distant objects, middle distance is blurred. In an effort to fix this issue, progressive lenses were developed, which provide wearers with and intermediate or transition part of the lens that allows your eyes to focus on distances that are somewhere in the middle. But what creates this effect? Well, progressive lenses are expertly curved, unlike a bifocal lens, which is harshly divided. For this reason, progressive lenses are also called no-line lenses.
Progressive lenses, although better, can take a small period of time to get used to. While the subtle transition of progressive lenses results in a product that is aesthetically pleasing, the lens's areas of focus are relatively small, because they all need to fit.
Bifocals are still used though; they are helpful for children and teenagers who have a hard time focusing when reading.
It's also important to get fitted properly, and not resort to store-bought bifocals. Most of these types of glasses are one-size-fits-all, which means that the prescription is the same in both lenses and that the optical center of the lens is not customized for the wearer.
If you've been fitted with an inaccurate prescription you may find yourself suffering from eye strain, discomfort and even migraines. Unfortunately, presbyopia is just a part of aging. But keep in mind that multifocal lenses can make all the difference.