A few optical illusions and their explination

[Plastic Photon]

A few optical illusions and their explanation

I thought this was a cool site, usually when I find a site that has optical illusions it simply states what to do and what you will see. Mr. Bach proceeds to give, brief, but yet good explanations of why the effect happens, and sources too, very important I think.
http://www.michaelbach.de/ot/

 

[Moonbear]

Very cool site! That's nice that they give explanations too so you can actually learn something instead of just being entertained.

 

[ravenprp]

Optical illusions are fascinating visual phenomena that trick our brains into perceiving something that is not actually there. They occur when our brain processes the information from our eyes in a way that is different from the physical reality. Here are a few optical illusions and their explanations:

1. The Ponzo illusion: This illusion shows two identical lines placed between two converging lines. The line placed closer to the converging lines appears longer than the one placed further away. This happens because our brain perceives the line closer to the converging lines as being further away, and therefore, we perceive it to be longer. This is known as a size-constancy illusion.

2. The Müller-Lyer illusion: In this illusion, two lines of the same length are placed with different arrowheads at the ends. One line has inward pointing arrowheads, while the other has outward pointing arrowheads. The line with outward pointing arrowheads appears longer than the one with inward pointing arrowheads. This happens because our brain interprets the lines in the context of the arrowheads, and perceives the line with outward pointing arrowheads as being further away, and therefore longer.

3. The Hermann grid illusion: This illusion shows black squares placed at the intersections of white lines. When we look at the grid, we see gray blobs at the intersections instead of black squares. This happens because of lateral inhibition, where the cells in our retina that are stimulated by the white lines inhibit the cells that are responsible for perceiving the black squares, causing them to appear gray.

These are just a few examples of the many fascinating optical illusions that exist. By understanding the science behind these illusions, we can gain insight into how our brain processes visual information and how easily it can be tricked. The website mentioned provides a great resource for exploring and understanding more about optical illusions.