A ball appears to roll up a slope, but actually it is going down. Various objects that are shown in different shapes in the mirror in optical illusions are on display at Meiji University Museum. (Kenji Takayama)

A ball rolls up a slope. A circular cylinder changes its form into a star-shaped cylinder when seen in a mirror.

Everything is not what it seems at a special exhibition featuring false illusions that opened on July 13 at the Meiji University Museum in Tokyo’s Kanda-Surugadai district.

The creator of the works is Kokichi Sugihara, a Meiji University professor who researches visual illusions of 3-D scenes from a mathematical analysis perspective.

Previously, he created works by cutting and molding paper. But now, the job is done by 3-D printers and other devices.

A scene of a ball going up a slope is created through a design in which slopes are placed in a setting akin to the inside of a foot-warmer fixed in a sunken floor, a traditional Japanese table called “horigotatsu.”

The optical deception is even more severe when a viewer looks at it with just one eye as it is more difficult to grasp the perspective without looking at it with both eyes.

A circular cylinder can be seen as many different shapes, depending on the angle from which it is viewed, as the upper part of the cylinder is cut in shape.

Such tricks have already been applied to the real world, according to Sugihara.

“Optical illusions are used at tunnels and other places to control drivers' speed,” he said.

The exhibition will run through Sept. 8. Sugihara will present a session on optical deception on July 17, Aug. 23 and Sept. 5.