Pretty much every exhibit in this museum is dedicated to optical illusions. There's everything from the shrinking room (pictured above) to the mirrors maze and vortex tunnel.

The shrinking room is commonly known as an Ames Room, named after American ophthamologist Adelbert Ames, Jr., who created the first such room in 1946. When seen from a certain viewpoint (through a pinhole), the room appears cubic, even though it's actually shaped like a trapezoid, meaning its walls slant outward and its floor is on an incline. The room's far left corner is lower than the near right corner, which is why someone standing in one corner looks bigger than someone standing in another corner. This is also why someone in the room appears to be shrinking as they walk across the room.