PURPOSE: To illustrate pincushion and barrel distortion and correction thereof.

DESCRIPTION: This is a two-lens system with an iris between, modeling camera or projector lenses. For the purpose of this demonstration there are apertures preceding and following the lens doublet. Closing only the preceding aperture results i n barrel distortion, and closing only the following aperture produces pincushion distortion. Closing only the aperture between the two lenses results in no distortion.See below for optical components used.

SUGGESTIONS: This is not a really bright display, but is neat because of its application to real optical devices.


EQUIPMENT: Bright point source with condenser, ground glass screen, coarse wire mesh, iris on tilting holder and separate optical rail, 10cm focal length convex lens, iris, 10cm focal length convex lens, and iris,

SETUP TIME: 10 min.

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