Engineers invent a noninvasive technique to correct vision

Nearsightedness, or myopia, is an increasing problem around the world. There are now twice as many people in the US and Europe with this condition as there were 50 years ago. In East Asia, 70 to 90 percent of teenagers and young adults are nearsighted. By some estimates, about 2.5 billion of people across the globe may be affected by myopia by 2020.