MIT Media Lab’s has demonstrated an optometry system called NETRA that uses a standard mobile phone display and an inexpensive hardware add-on.
"Our device has the capability to make routine eye exams simpler and cheaper and therefore more accessible to millions of people in developing countries," said MIT spokesman Manuel M. Oliviera on the MIT’s YouTube video.
The NETRA system demonstration utilises an Android application and a small plastic device that clips onto the front of the smartphone’s screen. The user looks through the device and uses controls to move lines until they begin to overlap. The process is repeated eight times with the lines and different angles for each eye.
It’s clear that the system is not in any way a replacement for a visit to a professional optometrist, not the least because they can gain more accurate results as well as performing other vital health checkups by peering into the eye manually.
That said, traditional optometry equipment is large, complicated, expensive and requires expert operation. Group member Ankit Mohan explains: "What’s really great about our technique is that it involves no moving parts and that all the intelligence is in the software so we can make it really cheap and easily accessible."
The optical device is derived from one which the group had developed previously in the development of an advanced form of barcode which the group called ‘Bocodes’. On the YouTube video Ramesh Raskcar describes the discovery when his wife was unable to view Bocodes with one eye but could with the other, and reminded him that she had differential vision, Eg. a different prescription in one eye.
While the main application will be the developing world, there may be some interest in the ability for the general public to more easily check their prescription and potentially check for changes in prescription which could serve as the cue to visit an optometry professional.
MIT have further details on the NETRA project here.