Questacon > Kids > Online Science Activities > The ABCs of Lissajous Patterns

Online Science Activities

The ABC's of Lissajous

Move the horizontal and vertical sliders to create patterns.

The patterns on the screen are called Lissajous patterns, named after a French scientist of the nineteenth century.

A fast moving bright dot traces the patterns on the screen. You can control the dot's side-to-side speed (horizontal speed) by moving the horizontal slider. You can control the dot's up-and-down speed (vertical speed) by moving the vertical slider.

Try making these patterns:

• Circle shape — adjust the dot's horizontal speed to equal its vertical speed.
• Australian Broadcasting Corporation (ABC) logo — adjust the dot's vertical speed so that it is 3 times faster than its horizontal speed.

Using Lissajous patterns

Electronics engineers use Lissajous patterns to measure radio signal frequencies. They do this by analysing the type of pattern an unknown signal makes when it is combined with a signal of known frequency.