Contact lens- A substitution for Eye Glass

A contact lens (also known simply as a "contact") is a corrective, cosmetic or therapeutic lens usually placed on the cornea of the eye. Modern contact lenses were invented by the Czech chemist Otto Wichterle.

Contact lenses usually serve the same corrective purpose as conventional glasses, but are lightweight and virtually invisible — many commercial lenses are tinted a faint blue to make them more visible when immersed in cleaning and storage solutions. Some cosmetic lenses are deliberately colored for altering the appearance of the eye.

People choose to wear contact lenses for various reasons. Some are listed below:

• Many consider their appearance to be more attractive with contact lenses than with glasses.
• Contact lenses are less affected by wet weather, do not steam up, and provide a wider field of vision.
• They are more suitable for a number of sporting activities.

Types of Contact lenses

Corrective contact lenses

A corrective contact lens is a lens designed to improve vision. In many people, there is a mismatch between the refractive power of the eye and the length of the eye, leading to a refractiion error. A contact lens neutralizes this mismatch and allows for correct focusing of light onto the retina. retina. Conditions correctable with contact lenses include near (or short) sightedness (myopia), far (or long) sightedness, etc.

Cosmetic contact lenses

A cosmetic contact lens is designed to change the appearance of the eye. These lenses may also correct the vision, but some blurring or obstruction of vision may occur as a result of the color or design. Theatrical contact lenses are a type of cosmetic contact lens that are used primarily in the entertainment industry to make the eye appear pleasing, unusual or unnatural in appearance, most often in horror and zombie movies. These lenses have been used by Ray Park as Darth Maul and Ian McDiarmid as Darth Sidious in Star Wars. Other frequent wearers of contact lenses include Paris Hilton, Britney Spears, Naomi Campbell, Brad Pitt, Tom Cruise and Arnold Schwarzenegger

Therapeutic contact lenses

Soft lenses are often used in the treatment and management of non-refractive disorders of the eye. A bandage contact lens protects an injured or diseased cornea from the constant rubbing of blinking eyelids thereby allowing it to heal. Contact lenses that deliver drugs to the eye have also been developed.