Contact lens rests on the cornea atop a permanent supply of tears. The pressure executed from the eyelids while blinking also act as the support to hold the contacts in place. The pressure executed by blinking make the contacts move a bit and glide over the cornea. This little movement allows tears, floating underneath, to smoothly flush the trash out which accumulates in the eyes.
That's how contact stays on your eyes, providing a crystal clear vision. But the way they fix the vision problem is a completely different ball game.
There are several kinds of vision problems faced by people but the major four are Presbyopia, Myopia or Farsightedness, Hyperopia or Nearsightedness, and Astigmatism. The common problem in all these cases is that the retina can not properly focus light. And when your retina is not functioning properly, the result is blurred vision.
All contacts are made exclusively, depending on the vision problem they are required to correct. For example, if you are an astigmat, the optometrist will measure the cornea to make a pair of contacts which will fit perfectly in your eyes. Now the rays of light will get placed to one particular point on your cornea resulting into sharp vision.
The lenses for Myopia or Farsightedness are very thin in the middle but thick on the edges. This makes retina process the light rays properly.
The lenses for farsightedness are exactly the opposite – thick in the middle and thinner on the edges – resulting into sharp vision and comfort.
The basic technology is the same for all kinds of contacts – redirecting light to a particular point on the retina. The difference is in their making as they have to treat different eye problems and the shape of cornea differs in each problem.
To provide more options and facilities to the users, four kinds of soft disposable lenses are available in the market. They are a) Daily disposable – to dispose every night before going to sleep; b) Bi-weeklies – can wear for two weeks before trashing them c) Monthly disposables – extended wear for 30 continuous days at a stretch; d) Yearly traditional disposables – the wearing tenure is for one year.
For those planning to buy contact lenses, here are some handy suggestions. Buying contact lenses online is a more affordable option than purchasing them from your neighborhood optician. Online suppliers offer lower prices as they buy contacts in bulk and have no overhead costs like showrooms do. And what better portal than lenskart.com, which provides you with unbeatable prices, convenient payment options and quick delivery.