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Lecture Series for Those Who Stay Home
World of 3D Optical Illusion
Many people are fighting against the new coronavirus, but I cannot do anything except for just staying home. So I decided to start this series of lectures of 3D optical illusion with the hope that they could entertain those who stay home. It is my pleasure if you could enjoy them. (Related links are
here.)
One general remark is that seeing videos is quite different from seeing 3D objects directly. When we see objects directly, we can use two eyes and hence can understand the depth relatively easily. On the other hand, seeing videos is essentially equivalent to seeing objects by one eys, because a video camera has only one lens center. Some of the illusions presented here do not occur when we see the objects directly. Anyway you may enjoy all of the illusions as long as you are watching the videos. [April 4, 2020]
In this series of lectures from 1 to 18 (except for Lecture 6), I showed my own theories together with my own illusion artworks. In Lecture 6, Lecture 19 and afterward, on the other hand, we choose general topics on 3D optical illusion that are known in this research area. In those cases also I use original material that I create myself. [July 28, 2020]
Lecture 1. Right-Facing Arrow
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Gallery of Facing-Right Objects
Lecture 2. Anti-Gravity Slopes
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Gallery of Anti-Gravity Slopes
Lecture 3. Height-Reversing Staircase
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Gallery of Height-Reversing Staircases
Lecture 4. Penrose Triangle
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Gallery of Anomalous Objects
Lecture 5. Circular Rectangle
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Gallery of Ambiguous Objects Made by Circular Rectangles
Lecture 6. Multiple Silhouette Objects
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Gallery of Multiple Silhouette Objects
Lecture 7. Height-Reversing Objects
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Gallery of Height-Reversing Objects
Lecture 8. Invisible Chicken
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Gallery of Partly Invisible Objects
Lecture 9. Ambiguous Cylinders
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Gallery of Ambiguous Cylinders
Lecture 10. Topology-Disturbing Objects
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Gallery of Topology-Disturbing Objects
Lecture 11. Card Marks Floating on a Mirror
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Gallery of Reflexively-Fused Objects
Lecture 12. Paper-Made Ambiguous Cylinders
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Gallery of Paper-Made Ambiguous Cylinders
Lecture 13. Ambiguous Tiling
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Gallery of Ambiguous Tiling
Lecture 14. Triply Ambiguous Objects
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Gallery of Triply Ambiguous Objects
Lecture 15. Ambiguous Objects with Six Interpretations
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Gallery of Ambiguous Objects with Six Interpretations
Lecture 16. Impossible Motion
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Gallery of Impossible Motion
Lecture 17. Figure Construction Methof for Ambiguous Objects
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Lecture 18. Ambiguety with Shadows
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Gallery of Ambiguety with Shadows
Lecture 19. Depth Reversal Illusion
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Lecture 20. How to Draw Impossible Figures
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Lecture 21. Pictures That Stand Up
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Lecture 22. Viewpoint Trick
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Lecture 23. Classical Illusion Caused by Depth Perception
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Gallery of classical illusion caused by depth perception
Lecture 24. Illusions That Might Be Caused by Depth Perception
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Gallery of illusions that might be caused by depth perception