About Vision > Normal Vision > What is Nearsightedness? > What is Farsightedness? > What is Astigmatism? > Eye Disorders and Diseases > Cataracts > Children's Vision

Light rays or images enter the eye through the front clear surface, or cornea. From here they travel through the lens of the eye where they are focused onto the retina. The retina is a thin membrane in the back of the eye which converts these light images into electrical signals. These signals are then passed through the optic nerve to the brain where "vision" results. Common Refractive Disorders: In a normal eye, light images are focused directly onto the retina for clear vision to result. However, in an eye with a refractive disorder, these light rays do not focus properly on the retina thereby resulting in blurred or distorted vision. The three most common refractive vision disorders are:

• Nearsightedness
• Farsightedness
• Astigmatism

Each of these can be compensated for with the use of glasses, contact lenses, or some form of refractive surgury.