Visual illusion
The Ames Room
A demonstration of the classic Ames Room illusion, where a distorted room appears cubic from a specific vantage point.
The Illusion
The Ames Room is one of the most famous optical illusions in perception psychology. Invented by ophthalmologist Adelbert Ames Jr. in 1946, it makes people or objects appear to grow or shrink as they move from one corner of the room to another.
How it Works
The room is constructed as a distorted trapezoid, but it is viewed through a peephole (monocular vision) that forces the observer to perceive it as a standard rectangular room.
- Distorted Geometry: As shown in the “Top View” panel, the left corner is much farther away than the right corner.
- Slanted Floors: As shown in the “Front View” panel, the floor slopes upward and the ceiling slopes downward from left to right.
- Forced Perspective: The walls and windows are also trapezoidal, skewed to cancel out the effects of perspective distance when viewed from the “eye” point.
Because the brain assumes the room is rectangular (a “carpentered world” assumption), it interprets the difference in retinal image size of the people not as a difference in distance, but as a difference in physical size.