Visual distortions Visual illusions

Goering's illusion (fan illusion)

Straight lines are, in fact, parallel.

Illusion of Wundt (1896)

The lines in the center are, in fact, parallel.

Here, too, the lines are parallel.

Illusion cafe "Wall"
Are horizontal lines parallel?

Yes, parallel!

Illusion discovered by R. Gregory in the Wall Cafe in Bristol (Richard Gregory, 1979).

The red lines are straight, although they appear to be curved.

Illusion of Zollner (1860).

Parallel straight lines appear to be curved.

The illusion of Poggendorf (Poggendorf, 1860)

On one straight line lie the lines BC, not AC, as it seems.

An illusion with twisted ropes (James Frazer, 1908).
Is it straight or not?

These are parallel straight lines.

Illusion of Perelman
The letters are actually parallel to each other.

One more parallel straight lines

Lipps Illusion

The central parts of the lines are parallel to each other.

Vertical and horizontal lines are parallel.

Illusion of W. Erenstein (W. Ehrenstein, 1921)

The square seems distorted.

Blue squares appear unevenly painted.

The pattern bends inward?

All squares are not really distorted.

Is the pattern coming forward?

In the figure, all the squares are not distorted.

Thompson Illusion

In the above figure, the direct tangent to all circles of different radii seems to be a curve, since we involuntarily liken it to an upper curved boundary.

Illusion of J. Fraser (Fraser, 1908)

The figures are not spirals, but concentric circles.
James Fraser . "A new visual illusion of direction" // British Journal of Psychology 2: 307-337, 1908

Circles or spirals?

Orbinson Illusion

Inside the wheel is not an ellipse, but the correct circumference.

The circumference in the center seems distorted.

Circles are on the same line.