6A65.31 - Distortion - Coma

See paragraph one in the procedure section.
Code Number:
Demo Title:
Distortion - Coma
Off Axis Lens Effects
Area of Study:
Optics Table, 30 cm focal length lens, 48 cm focal length lens, Slide Projector (Distant Light).

Coma - Set up is the same as that for Chromatic Aberration. Turn the lens so that it is no longer perpendicular to the angle of the light from the slide projector. A figure that looks like a bow tie will be produced with one lobe red ringed and one lobe blue ringed.

  • John H. Moore, Christopher C. Davis, Michael A. Coplan,  "Coma",  Building Scientific Apparatus 2nd Edition,  p. 146.
  • C. Harvey Palmer, "Experiment A13: The Off-Axis Aberrations of Lenses",  Optics - Experiments and Demonstrations, John Hopkins Press, 1962.

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