Self-prescripting Eyeglasses for $1

More than 153 million people around the world with poor or no eyesight either don't have access to or can't afford vision correction, according to the World Health Organization (WHO). Ninety percent live in low- or middle-income countries, WHO reports, where optometrists are harder to come by and individually crafted lenses cost too much for many.

A British physicist, Josh Silver, wants to solve that problem. He has his sights set on the lofty goal of distributing one billion pairs of glasses, at $1 a pair, by 2020.

The glasses are round plastic frames with lenses made of clear sacs of silicon oil, sandwiched between two clear plastic circles.

As a wearer adjusts the dials he or she can control how much liquid is loaded into each sac (thereby custom forming each membrane's curvature); this fine-tunes the glasses to an individual's prescription. After the world comes into focus, the sacs are sealed off permanently with a small valve, and the adjusting mechanisms are removed.

Here is a video of Josh demonstrating his invention in a TED talk, via YouTube:

Source: Scientific American