Zollner illusion

[ tsuhl-ner; German tsœl-nuhr ]
/ ˈtsʌl nər; German ˈtsœl nər /

noun Psychology.

a spatial illusion in which parallel lines intersected by short oblique lines are perceived as converging or diverging.

Origin of Zollner illusion

1950–55; named after J. K. F. Zöllner, 19th-century German physicist