ALL ABOUT CONTACT LENSES Although the concept of contact lenses has been traced back as far as Rene Descartes and even Leonardo Da Vinci, contacts lenses as consumer products have only been in mainstream circulation for about 50 or 60 years. These were not liked products made of glass until 1971, when soft lenses became commercially convenient. Contact Lens technology are extremely recent. But what is the technique behind contact lens and how do they work?
WHAT ARE CONTACTS MADE FROM? Previously, contacts are made from glass. But those contacts were especially unpopular because they were relatively discomfort. Nowadays, Contacts are made of rigid material, Perspex, attained a larger degree of popularity. But contacts have some major problem. The
lenses did not grant oxygen to reach in the cornea, which can create detrimental effects on vision. Very recently, a rigid lens technology has been invented which permits oxygen and more safer and comfortable to wear.
Yet, most of the contact lense sold today are soft lenses. Hydrogel, a soft and jelly like material is the main material to make soft lens. Very few numbers of lens are made of silicon hydrogel. Silicon Hydrogels have both the intensely high oxygen permeability of silicon and the ease and clinical performance of regular hydrogels.
HOW DO CONTACTS CORRECT OUR VISION? Contact lenses correct our vision as like the glasses do. Contacts change the direction of the light rays, so that the light can focus accurately into our retina. When light does not focus perfectly into our eyes, that time Nearsightedness and Farsightedness occurred. Nearsightedness (myopia), is caused by light rays focussing slightly in front of your retina rather than directly on it, whereas if you have farsightedness, vision problems occur because light rays do not focus before they reach your retina. To counteract nearsightedness, contact lenses move the eye’s focus point backward onto the retina; if you are farsighted, they move it forward onto the retina. This is why lens powers that correct nearsightedness contain a minus sign, and those that correct farsightedness begin with a plus sign.
SUGGESTION FOR THE WEARERS: >>>
Choose those colored contact lenses which suits you most.
Place the contact lens on the tip of your index or middle finger, which should be dry or mostly dry. >>>
With the fingers and thumb of your other hand, simultaneously pull up on your upper eyelid and down on your lower eyelid. >>>
Position the lens on your eye while looking upward or forward, whichever you find to be easier. You also can apply the contact lens by placing it on the white of the eye closest to your ear. >>>
Gently close your eye, roll your eyes in a complete circle to help the lens settle, and then blink. >>>
Look closely in the mirror to make sure the lens is centered on your eye. If it is, the lens should be comfortable and your vision should be clear. >>>
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Do not place contact lenses in your mouth or use your saliva to wet them.
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Always rub contact lenses when you clean them, even if using a "no-rub" solution.