Beneficial Bifocal Lenses
Many people have difficulty reading newspapers and books because their eyes have experienced some changes due to natural aging.
In this case, they may need special reading glasses that are particularly made for material reading.
Another fact is that some people may still have myopia and need to wear regular prescription eyeglasses for distance vision.
This sounds a dilemma that those people are forced to put on their reading glasses while reading and then switch to prescription glasses for distance activities such as watching TV.
After the invention of bifocal reading glasses, this kind of switch is eliminated.
Bothered by the inconvenience and time-consuming factors of separate pairs of eyeglasses, the American statesman Benjamin Franklin cut his two lenses in half and fitted them one above the other.
In this way, originally simple bifocal lenses were invented, which could provide both close and distance vision.
After that, there have been a variety of mutations of this invention.
The bifocal eyeglasses had saved Benjamin Franklin a lot of time, which was quite important for a busy man of his kind.
In standard styles, the top half of a bifocal lens is designed for visibility at a distance and the bottom section for materials reading.
This design is natural because most people look down while reading and up while focusing at the distance.
Bifocal lenses with a Franklin's style have a distinct line separating the two parts, and sometimes they are called Executive lenses.
This is the most primary bifocal lens design.
Currently, there are still other designs of bifocals.
Progressive lenses remove the visible line in the lens, making bifocal lenses more natural.
Yet there are also different shapes of the reading zone in the bottom section of the lens.
A design of bifocal lenses is a round part for near vision, while some other bifocal lenses are equipped with a slanted 'D' or half-moon shape for close vision.
Although bifocal lenses may require a period of adaption in some people, the most beneficial advantage is that they can help wearers get rid of lens switches between separate pairs of eyeglasses.
In this case, they may need special reading glasses that are particularly made for material reading.
Another fact is that some people may still have myopia and need to wear regular prescription eyeglasses for distance vision.
This sounds a dilemma that those people are forced to put on their reading glasses while reading and then switch to prescription glasses for distance activities such as watching TV.
After the invention of bifocal reading glasses, this kind of switch is eliminated.
Bothered by the inconvenience and time-consuming factors of separate pairs of eyeglasses, the American statesman Benjamin Franklin cut his two lenses in half and fitted them one above the other.
In this way, originally simple bifocal lenses were invented, which could provide both close and distance vision.
After that, there have been a variety of mutations of this invention.
The bifocal eyeglasses had saved Benjamin Franklin a lot of time, which was quite important for a busy man of his kind.
In standard styles, the top half of a bifocal lens is designed for visibility at a distance and the bottom section for materials reading.
This design is natural because most people look down while reading and up while focusing at the distance.
Bifocal lenses with a Franklin's style have a distinct line separating the two parts, and sometimes they are called Executive lenses.
This is the most primary bifocal lens design.
Currently, there are still other designs of bifocals.
Progressive lenses remove the visible line in the lens, making bifocal lenses more natural.
Yet there are also different shapes of the reading zone in the bottom section of the lens.
A design of bifocal lenses is a round part for near vision, while some other bifocal lenses are equipped with a slanted 'D' or half-moon shape for close vision.
Although bifocal lenses may require a period of adaption in some people, the most beneficial advantage is that they can help wearers get rid of lens switches between separate pairs of eyeglasses.
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