Phoropters and Aberrometers are widely used for determining prescriptions for eyeglasses. For developing nations, access to these systems is extremely limited. They are expensive, and delivery of this equipment to remote locations around the world can be a daunting task.
According to the World Health Organization, uncorrected refractive errors are the second highest cause of blindness, which affects about 2 percent of the world’s population.
Engineers at MIT’s Media Lab have developed a new, simpler and cheaper way to obtain prescription information from patients using camera lenses mounted on cell phones.
Preliminary testing on 20 people produced results comparable to the standard aberrometer test.
The aberrometer is the most expensive system and works by shining a laser into the eye, which uses an array of tiny lenses to measure its characteristics—with no interaction from the patient.
Apart from the software that runs on the phone, all that’s needed for this invention to work, is a snap-on plastic device, which researchers said can be produced at a cost of about $1 to $2 today—but could cost only a few cents in large quantities.
The patient looks into the small lens, and presses the phone’s arrow keys until sets of parallel green and red lines just overlap. This is repeated eight times, with the lines at different angles, for each eye. Researchers explained that the whole process takes less than two minutes, and the software provides the prescription data. “Our device has the potential to make routine refractive eye exams simpler and cheaper, and, therefore, more accessible to millions of people in developing countries,” said Professor Manual Oliveira.
This simple, inexpensive and portable eye-testing device is expected to have a dramatic impact in parts of Africa and Asia, where it will initially launch.
