Optical illusions, also called visual illusions are images that trick our eyes and brain to show us something in an image that don’t really exists! (Or it appears to be much different form original one).   When our eye receives information, it transfers it to our brain. By looking on an optical illusion the information that our eye transfers to brain may not match with the real image. In other words our eyes and brain are deceived by that image! Optical illusions might occur due to many reasons. Some are real optical illusion while others are because of psychological effects. Psychological optical illusions are seen because of the color or brightness while position, size and movement might be responsible for others.

Cognitive illusions

Another type of Optical illusion is “Cognitive illusions”. Cognitive illusions may also have different kinds. They may be “ambiguous illusions” which may lead to different interpretations of the image and mostly leads to ambiguity. Impossible cube is an example of ambiguous illusions.

One of Cognitive illusion is Paradox illusions. These illusions shows some objects whose existence is either impossible to exist or it is impossible to understand. If anyone tries to understand the object it only leads to ambiguities. Example of Paradox illusion is “penrose triangle”.

Another type of Cognitive illusion is “distorting illusion”. Distorting illusions are may show us different lengths of things having same length or non-parallel lines that are actually parallel.

History of optical illusion

All these types of optical illusion are drawn and are being used to amaze us for centuries. Nobody knows exactly that when these optical illusions were first drawn or who invented them first to doge our eyes and brain. Because the history of visual illusions goes as far as 500 B.C. philosophers at that time knew that our senses are not as much accurate and they can be tricked! It’s not only about our eyes and brain it’s also about our other senses. As we feel outside temperature warmer if we stay in a cold room for some time. It’s probably not that it’s hot outside but because we’ll feel that the temperature is very high and thus we are making a wrong guess!

Deceiving our eyes like other senses was also possible and people at that time realized this very well. In 1826 a psychologist named Johannes Mueller used the term “visual illusions”. Before that there was no appropriate name for optical illusions (at least we don’t know one). In 1854 a psychologist named continued published some optical illusions and they got very popular among people. In 20th century the concept of optical illusions was quite wide spread and ordinary people were quite  familiar with it. In 1915 a cartoonist named W.E. Hill published an optical illusion that was showing tree different persons in one picture which appeared to be a photo of one person only!

Many artists tired to draw illusions after that. Even today new optical illusion are created to trick our eyes and amaze us but in a little advance way!