As the name indicates, bifocal reading glasses are glasses with two distinct optical powers. These glasses are usually prescribed for presbyopic individuals who also need a correction for myopia or astigmatism. Being popular nowadays, bifocal reading glasses can be dated back to around 1760, when the America statesman and investor Benjamin Franklin first developed them. Suffering presbyopia and nearsightedness, the great man thought it was really inconvenient to switch between two pairs of prescription glasses. Even if there are still serious historians suggesting that there were others who had preceded Franklin in the invention of bifocal reading glasses, Franklin is certainly among the first to wear bifocal glasses.
An original version of bifocal reading glasses was made of the most convex lenses for close viewing in the lower half of the lens and the least convex lenses on the upper half. In the early 20th century, a new design using two separate lenses cut in half and combined together was invented. However, such a design had long been associated with a number of complications such as fragileness. At the end of the 19th century, Dr. John developed the technology of lens fusing, with which the two separate half lenses could be fused together appropriately. Nowadays, the production of bifocal reading glasses is further different. Manufacturers of bifocals usually mold a reading segment into a primary lens. In addition, such a reading segment is available in a variety of shapes and sizes, offering customized versions for individuals with specific occupations. Currently, the most popular design is the D-segment with 28mm wide.
Even if there are some design variations of bifocal reading glasses, the basic style has remained untouched since the first pair. The upper section of a bifocal lens is for distance vision and the bottom part for viewing near objects. This fundamental design is based on the fact that most people will tilt their heads slightly upwards in order to see a distant object and downwards for a near focus. This basic design enables presbyopia folks to benefit from those bifocal reading glasses in a natural way. In fact, bifocal glasses are being enjoyed by a large number of individuals with both presbyopia and nearsightedness. Bifocal glasses are generally considered healthier for people’s eyes, because the eyes can always see through the correct prescription lens. It is estimated that approximately 4 million Americans develop presbyopia each year, most of which are between 35 and 50 years old.
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In our daily lives, it is very common to hear people’s complaints that their eye sights are declining unceasingly, though with eyeglasses. But I accidentally find that most of those eyeglasses they worn are not prescribed or accurately prescribed. If so, vision degeneration can not be avoided. In fact, if they wear prescription eyeglasses, their vision will not get lost, but enhanced. Therefore, I strongly suggest those who have neglected this to wear prescription eyeglasses. Those eyeglasses are accurately prescribed according to wearers’ individual circumstances. Maybe some people think I have exaggerated about the function of prescription eyeglasses. Henceforth, I just want to list some information about those eyeglasses.
As their names implied, prescription eyeglasses are eyeglasses that are prescribed by some professors. And the process of prescription is the key and most complicated round, without which, the quality of eyeglasses can not be guaranteed. Let’s see how complicated it is.
One should go to an optical store first if he has made his decision to wear eyeglasses. Then, he will have to receive some related eye examinations and tests which can tell whether he is the candidate for eyeglasses or not, and the detailed information of his eyes will also be collected. Based on the collected information, the optometrist begins to “prescribe”. Many items will be considered in prescription, for the prescribed eyeglasses must aim at the problems in his eyes. For example, in some situations, distance vision and near vision are essentially taken into consideration while prescribing bifocal and trifocal eyeglasses.
Moreover, some people have seldom noticed that the lens power in their two eyes varies a lot in most cases. And such situation should also be taken into consideration.
The above mentioned information is just some of the commonest steps and items in prescription. While in actual situation, more are involved. Most of the eyeglass wearers have never considered which procedures are important for their eyeglasses; or what potential problems may occur if some items are neglected in the prescription process?
Thereof, I can not imagine what may happen to those who do not wear prescription eyeglasses or how much will they suffer just because of this. Generally speaking, prescription eyeglasses can cure almost all eye problems, though such problems may vary a lot on different people. Myopia and farsightedness, etc. are some of the commonest eye problems that can be treated with those eyeglasses. Besides, many other complicated eye problems can also be tackled; such as glaucoma, astigmatism, and so like. In a word, the symptom of those vision problems will not get worsened once people have worn their individual prescription eyeglasses.
In addition, prescription eyeglasses can also ensure that the wearers are looked very cool. That’s also one reason why I have said those eyeglasses are essential for wearers. No one can resist the temptation of a pair of prescription eyeglasses with present fashionable elements. One can ask the opticians to add some fashionable features into his eyeglasses after they are prescribed. Doing so can make eyeglasses much more perfect.
Anyway, prescription eyeglasses can help eliminate many bothering matters people may encounter in their daily lives if they have some eye problems. If any one who is now being bothered by eyeglasses, he is suggested to have a try on prescription eyeglasses. I believe his life will be greatly bettered.
Firmoo.com is the emerging online optical store selling high quality eyewear, such as prescription eyeglasses (single vision myopic glasses, reading glasses, bifocal and progressive eyeglasses etc.,), prescription sunglasses (with RX tinted lenses), prescription sports goggles. Firmoo guarantees lowest possible price in the market. Firmoo’s return and refund policy makes any purchase risk-free ones.
Article Source:http://www.articlesbase.com/vision-articles/why-are-prescription-eyeglasses-essential-for-people-with-eye-problems-1705344.html