2023 年 22 巻 2 号 p. 4_1-4_12
An ordinary 3D object, when reflected in a mirror, reverses its orientation along the line perpendicular to the mirror surface. However, some objects defy this expectation due to an optical illusion. This paper concentrates on one such visual phenomenon, in which a 3D object looks like it is translated in a mirror reflection, instead of having a reversed orientation. We name this phenomenon the “translation illusion.”We consider mathematical conditions for this illusion, propose an algorithm for designing this class of 3D objects, show various examples, and discuss possible extensions for providing a new technique to create 3D artwork.