Bifocal Glasses or varifocal glasses as they’re also called are a wonderful invention and supposedly come from Benjamin Franklin. Let’s first have a look at what bifocals are and what they’re made for. Bifocal glasses are a special type of vision glasses used to correct vision problems such as myopia. Contrarily to regular glasses which correct one type of vision disorder only, bifocals have two or multiple vision corrections built-in so that you can do two types of seeing without changing glasses. This is good for people who have very specific seeing disorders such as the elderly who often need a correcting pair of glasses for seeing afar and another one for reading text close to their eyes. With bifocals, they do not need to get two pairs of glasses anymore, but they can simply have the two correction integrated in the same glasses.
Now this integration can be done in several different ways. The cheapest of them all is the simple division of the lens in an upper half with one correction and a lower half with another one, and these glasses can easily be identified by the distinct strip which runs horizontally through the middle of their lenses, dividing the two zones. More elaborate designs are also available, like a smaller lens being integrated in shape of a half-sphere or moon in the lower middle of the main lens. But mostly people prefer buying lenses which do not have a distinct border between the two different zones and therefore look like ordinary glasses. These glasses look more esthetic, but they are somewhat harder to become accustomed to and a bit more expensive.
Whatever your reading disorder may be as an older person, if you have two distinct problems a pair of bifocals can instantly help you without the need for buying two pairs of different glasses and carrying them around all the time. Even if bifocals are more expensive than ordinary glasses, buying two ordinary pairs is still a lot more expensive than one pair of bifocals, and the improved comfort of wearing bifocal glasses should really more than make up for the price tag.