411 REFERENCE · Wiktionary
Oppel-Kundt illusion
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English
thumb|right|The part of the figure filled with some elements (upper, discretely; lower, continuously) seems longer than the unfilled part of the same length.
Etymology
Named after German physicists Johann Joseph Oppel and August Kundt.
Noun
An optical illusion that occurs when comparing the sizes of filled and unfilled parts of an image.
en Optical illusions
en eponyms