Thread: Top Phenomenon

When I was working at a museum there was a top with different lengths of black bars printed on top. When you spun the top the black bars would appear as various blurry colors that weren't actually present. I asked about this and nobody knew the name of the phenomenon and the best explanation I could get was, "it has something to do with the rods and cones in your eyes". Does anyone know anything about this phenomenon?

I have come across this before, there was an experiment on black and white TV which appeared to show violet green and yellow (I think), they did this by flashing patches, - If I remember the details I'll add to this post.

Off subject but here's a website to drive a slightly insane person over the edge:

http://www.illusion-optical.com/Optical-Illusions/

Originally Posted by zythum

When I was working at a museum there was a top with different lengths of black bars printed on top. When you spun the top the black bars would appear as various blurry colors that weren't actually present. I asked about this and nobody knew the name of the phenomenon and the best explanation I could get was, "it has something to do with the rods and cones in your eyes". Does anyone know anything about this phenomenon?

The BBC demonstrated this in the 1960s, before colour was introduced in the UK, on an edition of Tomorrow's World. They flashed squares at varying frequencies on screen, and these appeared coloured. It sounds like the same phenomena you describe.

[As a beautiful example of synchronicty I had been thinking of this demonstration this morning, for perhaps the first time in a couple of decades!]