A lot of people start to have problems with close vision during their 40s. This is called presbyopia. Fortunately, this doesn't mean that people who already wear glasses for nearsightedness need to own two pairs of glasses. This is all thanks to multifocal lenses, which correct both problems, making sure you always see clearly.
Before mulifocals, bifocals were widely prescribed, but they have a significant flaw; even though they help you to focus on both near and distant objects, everything in between is blurred. To rectify this issue, progressive lenses were invented, which give you and intermediate or transition region which lets your eyes to focus on everything between near and far distances. Progressive or no-line lenses are a type of multifocal lens that have a gradual curvature across the lens, rather than a sharp line separating the two areas of the lens.
However, it can take a bit of time to adjust to these lenses. Despite the fact that the invisible transition of progressive lenses is more elegant, the lens's areas of focus are relatively small, because they all need to fit.
Bifocals aren't entirely dated though; they are used to treat kids and teens who have a hard time focusing when reading.
Multifocal lenses work best when they're made to work with your specific requirements. So when it's time to get yours, make a point to work with a professional you feel comfortable with.
If you've been fitted with the wrong prescription you could end up suffering from headaches, eye strain or even nausea. During middle age, most people cannot dodge presbyopia. But it's good to know that good, multifocal lenses can enrich your vision, and your life.