Lesson 15: Lissajous Curves

Engineering students typically use oscilloscopes to plot waveforms repetitively in an amplitude versus time format (Ex: volts versus time). But oscilloscopes can also be used to plot traces in a channel-1 versus channel-2 format (XY mode) to produce Lissajous curves, which can produce interesting and sometimes rotating patterns on the oscilloscope’s display. This lesson shows how Lissajous patterns can used to tune/tweak frequency and phase parameters of a device-under-test based on a unique pattern.

#oscilloscope #scope #lissajous #lissajouspattern #lissajoustrace #lissajouscurve #measurement #measure

[thomassouthern]

This XY mode is supposed to give a linear signiture measuring a component or circuit path through a curve tracer octopus which gives voltage through channel one and current through chanel two. The two signals will have zero phase shift. The supply power to the octopus can be 115VAC stepped down to a much lower voltage through a transformer or the AC source can come from a waveform generator where you can control the frequency.

[electronicatutorial]

1. Physics and Engineering: Lissajous figures can be used to study and visualize the relationship between two periodic waveforms. They are often employed in the analysis of electrical circuits, particularly in oscilloscopes, to determine the phase and frequency differences between two alternating currents or voltages.

2. Sound and Music: Lissajous figures can be used in the field of acoustics to visualize and analyze the phase relationships between two different sound waves. By applying these figures, it is possible to study the characteristics of musical instruments, determine the harmonics and overtones present in a sound, and analyze stereo sound signals.

3. Laser Technology: Lissajous figures are used in laser technology for aligning and calibrating laser systems. By directing two laser beams onto a pair of X-Y galvanometers, the resulting Lissajous pattern can be observed. This technique enables precise adjustments and alignment of laser beams for various applications, including laser cutting, laser engraving, and laser show displays.

4. Mathematics and Education: Lissajous figures are used in mathematics education to illustrate concepts related to trigonometry, parametric equations, and the relationship between periodic functions. They provide visual representations of mathematical principles and can help students understand complex concepts in a more intuitive way.

5. Art and Aesthetics: Lissajous figures have an aesthetic appeal and can be utilized in art installations, visualizations, and design. Artists often incorporate these patterns into their works to create visually captivating displays or to explore the intersection of science, mathematics, and art.

[TheAlexandreom]

Congratulations for your good lecture. I use to apply Lissajous curves to analise signals from RFT (remote field testing) testing.

[Pismensky]

Many thanks for making and uploading this great explanational video.

[aturegano]

I was surprised by one application that @EEVBlog explained in his channel: calibration of measurement instruments through the alignment of 2 reference oscillators running at 10 MHz.

[larrybud]

Love to see a more advanced class now that this is 2 years old. Maybe some real-world troubleshooting? I also bought and repair an old analog tek scope just to do XY plotting. lol