This Ambiguous Cylinder Is An Amazing Optical Illusion To Trick Your Friends

Mirror, mirror on the wall!

This optical illusion uses a mirror that seemingly turns small squares into circles and vice versa. But interestingly, it’s not some mirror trick; it is the shape combination that makes use of your shifting perspective. The illusion was presented by Kokichi Sugihara of Meiji University, Japan for the “Illusion Of The Year” competition.

Speaking about this illusion, the competition said:

“The direct views of the objects and their mirror images generate quite different interpretations of the 3D shapes. They look like vertical cylinders, but their sections appear to be different; in one view they appear to be rectangles, while in the other view they appear to be circles. We cannot correct our interpretations although we logically know that they come from the same objects. Even if the object is rotated in front of a viewer, it is difficult to understand the true shape of the object, and thus the illusion does not disappear.”

Explanation of Optical Illusion

How does it work? First of all, as with many other optical illusions, there is only one optimal viewer position. Once you change it, the perspective might change while causing some drastic changes in the normal view of the eye.

Inclined angle
Inclined angle

The mirror is inclined. One can see that the top of the figure is not perpendicular. Moreover, apparently at the lower edge of the figure, there are some interesting details. One can conclude that the basic form of the “rectangular cylinder” is  a square with rounded corner edges.

Basic shape of the rectangular cylinder. Credits:
The basic shape of the rectangular cylinder


This figure will now be shown in the video from two different angles: one directly and the other one in the mirror. From the image, it is clear that this optical illusion only works if the angle to the object is identical to the angle to the mirror image of the object. Combination of these images is responsible for this optical illusion.

Red line: Direct view of object Blue line: Mirror Image view of the object. Combination of both these images give the optical illusion.
Red line: Direct view of object. Blue line: Mirror Image view of the object. Combination of both of these images gives the optical illusion.

Sugihara is known for working on Optical Illusion projects. Previously, his ‘Impossible Motion Illusion’s and his ‘Impossible Rooftop & Folding Ladder Illusions also gained massive popularity.

Behind every trick and illusion, there lies some scientific logics and explanation. Don’t you agree?

Leave a Reply

Your email address will not be published. Required fields are marked *