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principal plane
Examples
noun
,
Optics.
1.
a plane that is perpendicular to the axis of a lens, mirror, or other optical system and at which rays diverging from a focal point are deviated parallel to the axis or at which rays parallel to the axis are deviated to converge to a focal point.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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principal plane
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Word Value for
principal
15
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