Contact Lenses

Contact Lens means a thin disc worn on the inner eye. They are so close to the eye that they are in contact with the eye, hence their name!

They have been used since ages to cover a disfigured eye. But they were never popular for "good eyes", for the purpose they are used today, simply because they were not made of a comfortable material!

Here's an interesting story!

Types of Contact Lenses

Hard -

Used in olden days. Made of plastic, which allowed lesser gases to reach the cornea. So it was like covering your nose and trying to breathe. gives better correction if associated astigmatism.

Semisoft -

Better gas permeability than rigid/hard lenses. Better results for moderate myopia and astigmatism.

Soft lenses -

Higher gas permeability than semi-soft lenses. better for lower refractive errors. very easy to get used to.

Silicon lenses -

Highest gas permeability. Not yet freely available. Very delicate. Difficult to handle.

Extended wear lenses -

Can be used without removal for longer periods.

Disposable contact lenses

Can be worn once for an extended period and then disposed off.

Coloured contact lenses -

These are soft contact lenses. They are tinted with different shades.

Use

	Cosmetic purposes
	To decrease the disfigurement in a scarred eye.

Here's the interesting story!

It was the Second World War. Wounded soldiers filled the hospitals. They suffered a variety of painful injuries but strangely no one complained about a certain type of airplane plastic even though these pieces were there in their eyes! This was surprising. You know even a tiny dust particle in the eye is intolerable. So, this plastic must be special! Thus were born the modern contact lenses.

Contact lenses