A giant kaleidoscope
Step into an equilateral triangle made up of three mirrors. Observe the image produced as a result of multiple light reflections. Examine how the image changes as you move.
How it works
The image is a result of light reflected by three flat mirrors of the same size according to the laws of reflection (the angle between the surface an incident ray and a reflected ray remains the same). The image produced in this way is symmetric.
We think that rooms with mirror-covered walls were used in the past for a sophisticated kind of torture forcing people to look at the infinite number of their own reflections.