Information Madness

Now its no need of specialized equipment operated by a trained professional and all you can do at home with your mobile phone.

NETRA (Near-Eye Tool for Refractive Assessment), is a project of the Media Lab's Camera Culture research group. A small plastic device which currently can be produced for less than US$2. This can easily clipped onto a mobile phone screen. To use it, simply hold the device up to the eye, look into it, and use the phone’s keypad until two patterns overlap. This is repeated several times per eye, with the patterns at different angles. In this process software loaded onto the phone computes and provides the data needed to create a prescription. The whole process takes about two minutes.

As many as two billion people worldwide have refractive errors of the eye, and according to the World Health Organization, these errors, left uncorrected, are the world's second-highest cause of blindness. This technology surely helpful in in the developing countries for small size and low cost of the device.