Optical Wonderful
New to optical illusions?

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Try four different ways your brain makes sense of what you see. Begin with the picture, then open an explanation to learn what is happening.

  1. Ambiguous

    Duck-Rabbit Illusion

    One outline reads as a duck facing left or a rabbit facing right. Most people can't see both at once, and what you expect to see decides which comes first.
  2. Size & Perspective

    Müller-Lyer Illusion

    Two identical lines look different lengths because of the fins at their ends. Measure how far the illusion pulls your judgement in a one-minute test.
  3. Color & Contrast

    Checker Shadow Illusion

    Two squares on a checkerboard, one in shadow, are exactly the same grey, but almost nobody sees it until a bridge joins them. Why the brain reports surfaces, not light.
  4. Geometric

    Penrose Triangle

    Three beams that form an impossible closed triangle. Turn a real 3D model in the demo and find the one direction from which it becomes impossible.

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