Lesson 4 Define the terms principal axis, focal point, focal length and linear magnification as applied to a converging (convex) lens. Define the power. - ppt download
Lens Focal Length and F-stop | Digital Camera Know-Hows | Digital Camera | Digital AV | Support | Panasonic Global
File:Convex lens - Object on Focal point.png - Wikimedia Commons
Focal Point | COSMOS
Focal points and focal planes, Gaussian optics
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