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Fun optical chimaera

Posted: Tue Nov 26, 2013 12:53 pm
by hungerburg
Recently, the Feynman Lectures on Physics became free to read on the web. In the chapter on the eye - http://feynmanlectures.caltech.edu/I_36.html#Ch36-F1 - there is mention of an illusion. I had to give it a try, and QCAD is my tool of choice for such drawings: Although they are not strictly CAD, it has the right tools to construct certain 2D vector grafics.

So, attached the drawing and below a foto of what the thing looks like - beware though, that the effect is only visible with the real stuff, the foto cannot capture it. First I tried with the electric drill, but that went much too fast. More mundane it works when built as a top. Speed is very essential, one has to wait a little in order to see; especially in a dim room and the disc below a light bulb the effect will show very good.
ColourTop.jpg
Foto of the completed thing as a spinning top
ColourTop.jpg (153.87 KiB) Viewed 6148 times

Re: Fun optical chimaera

Posted: Thu Nov 28, 2013 2:18 pm
by Clive
Cool 8) , I'm going to laser cut some of these....so, that's all my Christmas presents sorted out - just kidding :lol: :lol: