Bifocals are not a new gift of science of recent times. It was first designed by Benjamin Franklin in order to do away with the continuous adjusting of glasses to align his vision with the shift of near and faraway objects. He designed a glass that allowed him to see the distant objects as clearly as he saw the nearer ones. Benjamin Franklin did this by simply cutting two pairs of different prescription spectacles in half and using half of each lens for each eye. Technology has advanced since then, but the basic way of making it is still the same.
The bifocals which were designed in earlier times had the concept, that generally people look downwards when reading or looking at something close, but looks up when looking at distant objects; this is why the bottom half of the lens was usually designed for close vision. Later versions of the bifocals had the lens cemented onto each other; as for today most bifocals are made by molding one reading lens to the other distant viewing one. The bifocals have many different designs, there are generally varied in their shapes and sizes. There are trifocals too.
Most people opt for bifocals for the vision problem, which is commonly known as presbyopia – the incapability of the eye to focus on objects at different distances. Presbyopia should not be mistaken for long-sightedness, although it is much misunderstood as such. Each year, almost 4 million Americans develop presbyopia, more commonly around their middle age, anytime in between thirty to fifty years of age. If you are a diabetic then you surely have a double chance of getting the handicap of presbyopia.
The first sign is the inabilities to focus your vision on something close, like reading newspaper, books etc. Presbyopia very slowly corrodes the falling years of old age of the patient, to get well you need the medication for almost two years. There is no way to stop it, although it has never been reported to cause a total and permanent blindness.
Bifocals are good for you as you can have your vision cleared, that is, when you use the prescribed lens. The first time users will face a problem when you start to use it; but as the day passes it will get well. It is also possible that things appear closer than they really are when you look through the lower part. The key is to use it and keep using it; the eye like various problems in our life has its own way of setting it right.
Generally the computer users and readers are much helped by the bifocals, as they are constantly changing their focus from one point to another. Some people complain of a ‘headache’ after using the bifocals, the headache or the ‘tired eye’ is just a scenario that you are facing as a new user. You may have to hold it farther away than natural. It is however recommended that after reading through your bifocal lenses you try to focus on something farther away, this will be a good exercise for your eyes and will help you in a long-term process.