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From: mcovingt@athena.cs.uga.edu (Michael A. Covington)
Newsgroups: sci.electronics
Subject: Re: Those little autofocus cameras
Message-ID: <1991Jun8.045145.18898@athena.cs.uga.edu>
Date: 8 Jun 91 04:51:45 GMT
References: <1991Jun8.020128.23216@milton.u.washington.edu>
Organization: University of Georgia, Athens
Lines: 12

I believe they work by comparing the fineness of detail in the image
at positions in front of and behind the intended focal plane.
Fineness of detail can be measured with just a couple of tiny photocells
by determining the difference between the light levels on them.
I hope someone who really understands autofocus will come on and post
a more thorough explanation.

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Michael A. Covington | Artificial Intelligence Programs
The University of Georgia  |  Athens, GA 30602   U.S.A.
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