NETRA (Near-Eye Tool for Refractive Assessment) uses a phone’s LCD display(iPhone) and intelligent software to administer a quick, effective and accurate vision test that patients can perform at home.

he NETRA test consists of a small plastic device clipped onto the phone’s screen. The patient looks into a tiny lens, presses the phone’s arrow keys to make a set of parallel green and red lines overlap, bringing view into sharp focus, and repeats this eight times for each eye as the lines appear at different angles. Software loaded onto the phone then provides the precise prescription data. It may sound laborious, but the entire process takes under two minutes.

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