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automated eye exams



I had an Opthamologist show me an explanation of these machines that he
was given by a B&L saleswoman. The paperwork says that the machine
attempts to form an image of a "fine" square array (grid) is formed on
the retina through the cornea. It then "views" an image of that image
as it comes back out through the cornea. adjustments are made be the
computer to its optics while it tries to form a correct clear copy of
the original on the camera focal plane. Edge detection and other
techniques are used to help the computer "bracket in" on the correct
perscription to be used so the optimal result is obtained including an
astigmatic correction, if necessary.


On Thu, 14 Nov 1996, Leigh Palmer wrote:

I think my comment about the reflector at the back of the fovea was
wrong; I think that pertains only to nocturnal predators like cats
and raccoons.

Speaking of eyes, on the weekend I was treated to an automated
optometric measurement. I looked into a machine very briefly with
each naked eye, and the machine printed out my prescription!
Would anyone out there like to let me in on how this machine works?

Leigh




ERTEL SENDS. _____________________
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/ jpe@nadn.navy.mil \
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