Which square is darker, A or B?

OPTICAL ILLUSIONS

What is an Illusion?

• illusions that deceive the human visual system into perceiving something that is not present or incorrectly perceiving what is present.

An optical illusion (also called a visual illusion) is characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source.

There are three main types:

• literal optical illusions •physiological illusions• Pathological visual illusions

Literal Optical Illusions

create images that are different from the objects that make them.

This is the This is the Bunny/Duck Bunny/Duck illusionillusion. At . At first glance, first glance, what do you what do you see? Now give see? Now give it some time, it some time, but do not but do not focus on one focus on one certain area, certain area, and then ask and then ask Yourself; what Yourself; what do Ido I really see? really see? Now, look Now, look again. You again. You might be might be surprised!!!!!!surprised!!!!!!

What do you see?

Try blinking quickly!

Physiological Illusions

Are the effects of excessive stimulation of a specific type (brightness, color, size, position, tilt, movement), and cognitive illusions, the result of unconscious inferences.

The ‘brown’ square in the centre top, and the ‘orange’ square in the centre front are exactly the same shade of brown.

Don't believe it?

Which is larger – the left or right hand card?

One face? Or two profiles facing each other?

Pathological visual illusions

• Arise from a pathological exaggeration in physiological visual perception mechanisms causing the aforementioned types of illusions.

Julian Beever creates pavement art. Many of his creations are optical

illusions, such as this one, where he appears to be perched on a ledge, waiting for Batman and Robin to

climb the building and rescue him.

In reality, there is just pavement in front of him – the rest is a 'trick the

eye'.

HOW DO OTICAL ILLUSION WORK?

Questions?

Exercises :

Are the two circles the same colour?

The "illusion" is that this is just a picture of coffee beans; but it is not. Can you find a man's face among the beans?

If you find the face in 3 seconds or less, the right half of your brain may be more well developed than most.

Look at the wildlife painting of a Bengal tiger.

Can you find the hidden tiger in the picture?

Read what the sign says

Make your own optical/ visual illusion. Choose one on bellow:literal optical illusionsphysiological illusions Pathological visual illusions

What do you see?

Do you see a ‘floating triangle’?

Are the linesparallel?

Totally straight lines?

The SCINTILLATING GRID – black dots appear at random intersections

Focus on a single intersection, the dot does not appear. The dots disappear if you are too close or too far from the image.

How many horses can you see in the picture?

Some people see 5, some 6 and some even see 7!

Can you see the Shark in the picture above. The trick is not to focus directly on the image but

try to focus on a point through the image. With a bit of patience and relaxation you CAN do it.

Move your head back and forward.

What happensto the

circles?

Focus on just the centre circle

while moving your head

How many circles

can you see?

Did you see the 16 circles?

If your eyes follow the movement of the rotating pink dot,

the dots will remain only one color, pink.

However if you stare

at the black " +" in the center, the moving dots turns to green.

Now, concentrate on the black " + " in the center of the picture. After a short period, all the pink dots will

slowly disappear, and you will only see only

a single green dot rotating.

How many legs does the elephant have?

“the hidden tiger” is written in the tiger

What do you see?

In black you can read the word GOOD; but the word EVIL also appears in white letters inside each black letter.

What word can you see?

What do you see?

You may not see it at first, but the white spaces create the word OPTICAL,while the blue landscape spells out ILLUSION

What do you see?

You probably read the word ME in brown, but....... when you look through MEyou will see YOU!

What do you see?

You should see a face ….

but also a word.

Tilt your head to the right – the word begins with L.

Read what the sign says

Count the people in the picture below.After they shift, count them again!

How many deer can you see in the picture?Just the one?

What do you see in this picture?

Can you see the baby?

This is called an "impossible object," which means that it's impossible to build.

But drawing it is not impossible, as you see in the image.

Perpetually ascending staircase...how can the man go up all the time

and come back to the same place over and over?

IMPOSSIBLE STAIRS

DIGITAL BUMPS

MOVING HEART

1 length of rope

…..or 2?

Two elderly faces, or a larger scene?

What can you see in the picture above?

Remember the trick is not to focus directly on the image but try to focus on a point through the image.

With a bit of patience and relaxation you CAN do it.

What can you see in the picture above?

And one final MAGIC EYE STEREOGRAM

Thanks for listening

Prepared by:MIRANDA,DAISY JANE G.