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Poor Vision? There's an App for that.

necro81 (917438) writes | more than 3 years ago

2

necro81 (917438) writes "Researchers at MIT's Media Lab have developed a smartphone app that allows users to measure how poor their vision is (myopia, hyperopia, and astigmatism) and receive a corrective prescription. The user peers through a $2 optical adapter at the screen of a smartphone. The app displays lighted bars, and prompts the user to adjust the display until the bars line up. Repeating this with bars in different locations and orientations allows the vision distortion to be determined to within about 0.4 diopters (using a Nexus One). The iPhone 4, with its higher-resolution display, should be able to improve that to 0.28 diopters. This could have broad application in the developing world, where experienced opticians and diagnostic equipment are hard to come by."

2 comments

ok... but (1)

butterflysrage (1066514) | more than 3 years ago | (#32777376)

This could have broad application in the developing world, where experienced opticians and diagnostic equipment are hard to come by

ok, but just how popular are iPhones?

Diopter (2, Informative)

necro81 (917438) | more than 3 years ago | (#32778054)

For those that don't know, the diopter [wikipedia.org] is a measure of the strength of a lens. The higher the diopter number, the more the lens can bend light. It is the reciprocal of focal length. Negative diopters cause parallel rays to converge (a convex lens); positive diopter leads to divergence (concave). A prescription for eyeglasses will be called out in diopters, indicating how strong the lenses in the glasses need to be to correct for focusing problem of the eyes. Typical reading glasses will be +1.0 to +3.0 diopter.

The project page points out that opticians typically prescribe corrective lenses in 0.25-diopter increments. So being able to diagnose a vision problem to within 0.28 diopters brings it close to what you would be able to readily get from any lens manufacturer.
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