of the Month #19: June·July 2012 Back | Home
this page you can test your visual ability with interactive
optical illusion challenges. Each month, we
will post new puzzling illusions to solve and/or to
comtemplate: ambiguous and completion figures, impossible
figures, hidden objects, illusions involving colors,
geometric illusions, illusory moving patterns, verbal
illusions and paradoxes.
these illusions were adapted/designed by the authors
with the aim of allowing the visitor/reader to:
• discover how we
• test and enhance
the power of observation and critical thinking skills,
• improve mental flexibility,
• have fun being deceived
by puzzling visual challenges.
You can use the SVI
feature below in your non-commercial webpage
for free as long as you leave the copyright and
author's info intact and link to
you explain why the 'black hole' in this still picture seems
holes are the most mysterious celestial bodies!
We can see in the picture a magnificent black hole
that seems to expand but, do not worry, it is just
an illusion! Strangely enough, when you move your
head away from the picture, the hole will appear
The effect by its nature, is quite opposite from
the other illusion called Troxler’s
fading or vanishing effect, but it works in the
same way. The solid central black ‘hole’ is
not expanding at all, as it is rather the outer blurred
surrounding that is slowly shrinking (in fact, disappearing)
due to unvarying visual stimuli, giving finally the
impression the solid black spot actually expands.
encouraged to expand and/or improve this article.
Send your comments, feedback or suggestions to Gianni
A. Sarcone. Thanks!
of Optical Illusions by G. Sarcone & M.-J.
The illusions will fascinate, challenge and trick
you, and the explanations of how they work will
encourage you to look differently at the world
we live in.
Iphone Skin by G. Sarcone
This 4-eyed cat will hypnotize your friends!
A funny picture for Iphone and Ipod.
Univers des Illusions d'Optique by G. Sarcone & M.-J.
La réalité est visiblement incroyable
! Plongez dans un monde fascinant où tout
n'est qu'illusion !
Les images clignotent, se déforment, tournent.
Attrapez le vertige en restant immobile ! Un
sujet qui fascine tous les publics, de 7 à 77
ans. Une mise en scène extraordinaire
et des images à couper le souffle !