Bifocals were invented by Benjamin Franklin. He was someone who was also near and far-sighted at the same time. He was tired of having to change up his glasses all the time, so he cut into the lenses with both of his glasses and fit one half of each type into the frame. Bifocals were created! This is the reason that bifocals are sometimes called a Franklin style.
It is interesting to see just how bifocals work. Because they have two types of lenses for each eye, a person can see both near and far away. The way this works is that there is an upper and lower lens. The bottom lens is for reading, and to correct the near vision. The top lens is for distance problems and helps the wearer see far away. However, the top lens does not always have any type of correction in it, if a person does not have a distance vision issue.
Bifocals have a distinctive line running horizontally through the middle of the glasses. This is the line where the two different lenses have been joined. These types are known as Franklin or Executive Glasses, or E Style bifocals. However, with recent technology, bifocals can come with no line in the middle, yet work exactly the same way. Progressive bifocals are the latest in eyeglass wear, and may also be referred to as a no-line bifocal. If you want to hide the fact that you need reading glasses, than these are the best type to buy. With progressives, the transition between eye problems is very smooth, meaning that you can easily look at something in the distance and then look down at your paper again without eye strain.
There are a few shapes that bifocals can come in to correct the near-vision problem. A half moon shape, also called a D-segment or flat top, can provide the wearer with a larger vision area. They can also be fitted to a smaller frame easier than they can a larger one. There are four types of the near vision part of bifocals that are the corrective part. The lower part of the lens is called the round segment. The ribbon segment of a pair of bifocals is the narrow part that is in a rectangle shape on the lower part of the lens. A semi-circle can be referred to as the half moon or flat top, and the cut half of a bifocal is the point where the two different lenses meet.
Bifocals can make a huge difference for the person who needs to see both far and near. Talk to your optician to find out if bifocals are right for you.
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