Two centuries ago, Benjamin Franklin took two pairs of glasses - one for distance and one for near and he cut them in half horizontally. Then he placed the top half of the distance lens on the lower half of the lens for near images. That was the first pair of bifocals. Nowadays, you can even find bifocal contact lenses.
Bifocal contact lenses are used to help against a condition called presbyopia. This is a common ailment that many people suffer from. A clear sign of this is when you need to move the newspaper or anything else farther from the eyes than usual to read or see clearly. Bifocal lenses work on the same principle as bifocal glasses. They have dual function and correct distance vision and near vision. They also can come in different colors.
It is important to understand how these lenses work. As we age our eyes’ ability to distinguish objects either remote or close diminishes. This happens even if you are not wearing glasses. Bifocal lenses compensate for presbyopia by providing two focal centers on the surface of the lens. The problem with bifocals is that in reality we need to be able to look at all distances, not only near and far. They require a period of adjustment for the eye to form reflex eye movement.
Even the best contact lenses can be found easily. Many optometrists prefer to prescribe the type of lenses that can be worn for a day and then should be replaced. The main reason is the low risk of infection. They are generally cheap and are available in packages. There are others that should be changed after a period of two weeks, or even after a month. But you still need to clean them with a special solution even if you change them regularly. The cheapest place where you can buy the best contact lenses is the internet. But before shopping for contact lenses you should see an optometrist, and also you should come for a consultation every time you feel something strange with your eyes.
A lot of people believe that applying contact lenses is a difficult or even painful procedure, which is totally wrong. It is true that it will be a little difficult in the first days, but with a little practice you can get to the performance of putting them on and taking them out even without the help of a mirror! In general, the lens is applied on the inner corner of your eye while the eye is held wide open and the globe is directed towards the outer corner. Then you have to blink a few times until the lens is perfectly placed on the iris. Removing the lens is considered a bit more difficult. While you gaze up at the inner corner of the eye, you have to direct the lens to the outer corner of the eye and take it out. It is possible that this description should appear to be complicated because you're not used to having something applied directly to the eye. Moreover, you do not necessarily need to follow these instructions step by step, but depending on the shape and size of eyes, you can decide for yourself how you can apply the lenses.
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Find out which are the best contact lenses for your specific situation. If your vision is not so accurate both for close objects and those placed in the distance, then you need bifocal contact lenses.
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