This optical illusion is more effective for certain parameters than others. What settings make the lines look least parallel to you?
The Story of Spikey—Stephen Wolfram Writings
Maths Ed Ideas: 2018
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Halftone - Wikipedia
How can mathematics say that parallel lines meet at infinity? What is the concept behind it? - Quora
Wolfram Demonstrations Project, illusory Motion, concentric Objects, Optical illusion, illusion, rotation, brain, spiral, optics, geometry
Grids of Lines - Wolfram Demonstrations Project