What is an anamorphic illusion? I found this clever demonstration at Science World, which now that I think about it, was more trippy than I expected. Notice how the shape looks distorted on the disc but looks like a perfectly normal star on the mirror image seen on the cylinder. You need to find the right angle for it to work.
This illusion goes as far back as the 17th century. Although it seems like a useless party trick, it has been applied in fields like architecture, cognitive science, marketing, film, education, and so on. It has also been used to create the illusion of 3D in digital displays without the need for VR goggles.
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