Lissajous figure

Named after French mathematician Jules Antoine Lissajous (1822–1880), who invented an apparatus that projected such figures onto a wall.

Lissajous figure (plural Lissajous figures)

1. (mathematics) A plane curve traced by a point which executes two perpendicular independent harmonic motions, the frequencies of which are in a simple ratio.
   • 1966, Thomas Pynchon, chapter 3, in The Crying of Lot 49, New York: Bantam Books, published 1976, →ISBN, page 30:

     The Scope proved to be a haunt for electronics assembly people from Yoyodyne. The green neon sign outside ingeniously depicted the face of an oscilloscope tube, over which flowed an ever-changing dance of Lissajous figures.

• Lissajous curve

• Lissajous knot
• Lissajous orbit

• harmonograph