This story was originally reported by PRI's The World. For more, listen to the audio above.
Eye exams simply aren't available for many people. The technology used to test people's eyes is too expensive and too difficult transport to remote parts of the world. Ramesh Raskar of the Massachusetts Institute of Technology told PRI's The World that there are half a billion people in the world living with uncorrected refractive errors in their vision that affects their livelihood. It can lead to both illiteracy and poverty.
"Although some solutions have emerged that allow you to create very cheap glasses," Raskar told The World, "surprisingly there is no easy solution for measuring the error."
A new technology developed by Raskar could make it easier to bring eye exams to some of the most hard-to-reach parts of the world. The system requires a smartphone, some software, and a plastic lens attachment that costs about $2.
The system is meant to be "a thermometer for your vision," Raskar says. Patients use the phone's arrow keys to try to line up parallel red and green lines, so it's easy to use for speakers of any language. It takes about two minutes for people to get a prescription.
Right now, the system uses the extremely high-resolution screens on smart phones, combined with the software from app stores, to run the tests. In theory, though, the system could use a wide range of cell phones.
Considering the rapidly expanding cell phone market throughout the world, Raskar believes the opportunities for this kind of system will continue to grow.
You can watch a video of the technology below:
PRI's "The World" is a one-hour, weekday radio news magazine offering a mix of news, features, interviews, and music from around the globe. "The World" is a co-production of the BBC World Service, PRI and WGBH Boston. More "The World."