Many people begin to notice problems with close vision during their 40s. This is called presbyopia. It's comforting to know that having presbyopia when you already need glasses for distance vision doesn't mean you now need two pairs of glasses. This is because of multifocal lenses, which can take care of both problems, ensuring that you always see well.
Before mulifocals, bifocals were widely prescribed, but they have a significant shortcoming; even though they correct problems with both near and distant objects, middle distance is blurred. To create something more helpful, progressive lenses were developed. These provide wearers with a transition region 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 sectioned. Because of this, progressive lenses are also known as no-line lenses. This creates not only better vision at near and far distances, but also nice, easy transitions between the two.
These lenses, although better, may take a small period of time to get used to. Even though the subtle lens curve is more aesthetically pleasing, the lens's areas of focus are relatively small, so that there's also room for transitional areas.
While these days, multifocal lenses (or trifocals) are for presbyopia, bifocals are often used to treat children or adolescents who experience eye problems like eye teaming, or being unable to focus while reading, which in turn, can lead to eye strain.
It's also crucial that you get fitted properly, and avoid drugstore bifocals. Most of these types of glasses have the same prescription in both lenses, which will not help a lot of people.
If your prescription or fit is off you could find yourself suffering from eye strain, discomfort and headaches. During middle age, most people will not be able to avoid presbyopia. But it's good to know that good, multifocal lenses can enrich your vision, and your life.