Jules Antoine Lissajous

Jules Antoine Lissajous ( born March 4, 1822 in Versailles, † June 24, 1880 in Plombières -les- Bains ) was a French physicist.

Lissajous made ​​famous by the eponymous Lissajous figures, resulting from the superposition of linear oscillations. Their shape is dependent on the frequency and the phase angle difference existing at the beginning. With unequal frequencies results in a steady figure, when both frequencies form a rational ratio. Otherwise, the path curves not repeat the Lissajous figure is constantly changing. With equal frequencies of different ellipses eccentricity arise.

In 1855 Lissajous described a method for the preparation of such vibrations. In 1873 he was honored by the Academy of Sciences with the Lacaze Prize for his work on observation, measurement and interpretation of vibrations. A simple experimental arrangement for imitation of Lissajous work might look like this: A pendulum is suspended so that the pendulum can not only move in one plane but in different directions. It is first offset by a surge in vibrations. Then another shot, the pendulum receives in a different direction. Now the pendulum performs the same vibrations in two different directions, with the result that the path of the pendulum mass, although a very complicated, but self-contained line, namely, a Lissajous curve describes. They can record by using a sand-filled funnel as vibrating mass, from which flows the sand slowly.

A first description of such figures Nathaniel Bowditch wrote in 1815 in connection with the attempt to simulate the apparent motions of the moon.

In the space of Lissajousorbit is named after Lissajous.