lissajous curves/figures

Jun 2019
1
0
I have found myself in a position where i need to learn more about lissajous curves/figures. I have come across them before but only ever setup equipment to show the different types of patterns.
I now need to understand more on how to use and interpret a lissajous in a practical sense as in how to make sense of the patterns when hooked up to a circuit.
Can anyone explain how a lissajous is used and how to make sense of the images produced. Or maybe point me in a direction that may help me to learn more about them with out going too glass eyed?
 
Aug 2010
434
174
What have you already looked up about them? It has been a very long time since I dealt with Lissajous figures but a Google search gave several websites. This one: https://www.bing.com/search?q=lissajous+figures&form=EDNTHT&mkt=en-us&httpsmsn=1&plvar=0&refig=73d8c2b95f5c47f4b96ca27991d41e4e&PC=HCTS&sp=2&qs=SC&pq=lissajou+&sk=SC1&sc=8-9&cvid=73d8c2b95f5c47f4b96ca27991d41e4e&cc=US&setlang=en-US
defines them as "graph of a system of parametric equations x=Asin(at+δ), y=Bsin(bt)" (I hadn't remembered the "\(\displaystyle +\delta\)", I just used x= A sin(at) and y= B sin(bt) so the curves all passed through (0, 0).)
 
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Jun 2016
1,190
555
England
Alternatively try:
<Lissajous Figure Definition>

"any of a number of characteristic looped or curved figures traced out by a point undergoing two independent simple harmonic motions at right angles with frequencies in a simple ratio."

This gives a hint toward the type of usages I have seen them used for,
comparing the characteristics of two (related) signals.

If you feed a sinusoidally varying signal into the X channel of an oscilloscope
and a different sinusoidally varying signal into the Y channel of the oscilloscope
then it will display Lissajous figures.

The pattern of the figure has a direct relationship with the frequency differences of the signals
 
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