Why Billions Do Not Have Glasses: BBC

As many as 2.5 billion people worldwide need but do not have eyeglasses. The Vision Council of America suggests that 75 percent of adults need eyeglasses to read, drive and work. Glasses, often taken for granted in developed nations, support worker productivity and safety. Yet millions worldwide lack access to eyewear. “And many of those people may have no idea glasses could help them,” explains Tim Harford for BBC News. “Still, even conservative estimates put the economic losses from poor eyesight into the hundreds of billions of dollars - and that's before you think about people's quality of life or children struggling at school.” Harford describes the evolution of eyeglasses, beginning with their invention in the late 1200s, most likely in Italy, to modern-day digital glasses and augmented reality that allow precision work and increase worker productivity. Researchers tested vision of hundreds of tea-pickers in India and distributed inexpensive eyeglasses: 20 percent more tea was picked, with productivity higher among older subjects. Studies suggest that teachers often provide early alerts and trained nurses could test vision to provide eyeglasses. Harford concludes that 13th-century technology should be widely available.” – YaleGlobal