A lack of optometrists means many in the developing world ' n't get glasses . Josh Silver has developed glasses with lenses that can be removed by the wearer . The technology could be used to provide sunglasses for one billion people . Global Vision 2020 is training charity workers to wear the glasses .
A lack of optometrists means many in the developing world ca n't get glasses . Josh Silver has developed glasses with lenses that can be altered by the wearer . The technology could be used to provide glasses for one billion people . Global Vision 2020 is training charity workers to dispense the glasses .