The two most common eye defects are myopia (nearsightedness) and hyperopia (farsightedness). These defects arise from the failure of light rays to focus on the retina to form a clear image. People with myopia are unable to focus properly on distant objects but can see near objects clearly. Myopia is corrected by a concave lens (which curves inward like the inside of a bowl) placed in front of the eye. This lens helps to change the focus and cause images to fall on the retina. Those with hyperopia can see distant objects clearly but cannot focus properly on near objects. Since the lens has lost its elasticity, it is not thick enough to focus. Thus, the lens focuses light behind the retina instead of focusing on it. Placing a convex lens (which curves outward like the outside of a bowl) in front of the eye can correct hyperopia. Recent techniques for correcting eye defects include an artificial replacement lens implanted in front of the original lens through a tiny cut in the cornea.