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Summary
DescriptionFresnel only.JPG
English: Front view of Fresnel-lens cover used on window of typical passive infrared motion detector. Illuminated from behind by a single point light source. Each spot of light is one of 18 Fresnel lenses.
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Photographed and uploaded by me.
Author
Jack LaRosa
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Public domainPublic domainfalsefalse
I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
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{{Information |Description={{en|1=View of Fresnel lens window cover used on passive infrared motion detector. Lit from behind by a point light source}} |Source=Photographed and uploaded by me. |Author=Jack LaRosa |Date=07-26-08 |Permission= |other_version