The kaleidoscope effect
If we put any object between two incident mirrors at angle that divides 180° (45° in the picture), we get a kaleidoscope effect.
Exhibit of Simmetria, giochi di specchi - Symmetry, playing with mirrors.
© matematita
The image belongs to the sections...:
Images between two incident mirrors (From the exhibitions of matematita)
Further information:
http://specchi.mat.unimi.it