Myopia, or hypermetropia, is one of the most common vision problems. This is due to the fact that the human eyeball is not perfectly round. When a person looks at objects closely, his eyeball begins to shrink, and this causes image distortion. As a result, the eyes begin to focus on close objects, but distant objects may appear blurry. The most common type of myopia is severe myopia. People with this form of myopia have eyes that are usually too weak to cope with focusing on close objects. They use another device called accommodation. This is the process by which the lens of the eye contracts to move closer to the retina when a person approaches an object for close vision. Excessive accommodation can often lead to overstrain of the eye muscles, as well as an increased risk of developing glaucoma (swelling of the eyeball), cataracts (deformation of the lens), and retinal detachment (the inner layer of the eye). About 3% of the population are myopic. The exact mechanism of why myopia develops is unknown. About half of all nearsighted people have some form of myopia due to heredity. Some studies show that a sharp increase in the consumption of instant