anyone know what thing is this ?
 

When i was a kid , i went to exhibition of some kind, there on desk , there was this electrical thing with wire attached to it,

it had few leds on a single arm, then the guys started it and the arm started to revolve in the globe/circular motion and the leds made few words floating. looked very awesome.

anybody ? know what that thing is called ?

thanks

I forget what its called, but I know what you mean. It's based on the old persistence of vision illusion (http://en.wikipedia.org/wiki/Persistence_of_vision). It is 1, 2 or 3 rows of light that display words or images that are only visible when they are moving or spinning.

A company tried to turn this into rims for cars a few years ago.



Talk about tacky...

The illusion is called something like

Programmable LED message display?

http://ecx.images-amazon.com/images/I/51xP4tVK7RL.jpg

thanks man.

thanks.

this is it.,