A few friends and I have come up with the bold idea of doing something fun with the electronics skills we picked up at school, and we decided to make a rotating led display. This would be an array of leds, mounted perpendicoulous on a spinning rod, switching on and off very fast in a predefined pattern. Because of the slowness of the eye, the pattern of leds should remain clearly visible when it moves across the plane of sight, this phenomenon is know as persistence of vision (POV). This pattern can be anything from letters, words and sentences to entire pictures, depending on the size and complexity of the electronics.
The POV led toy we are going to make, isn’t going to be able to display complex figures, the goal is to display a single phrase, on 7 or 8 standard red leds, scrolling continuously through the air. We also want a way to update the display by means of a computer without switching off the motor. We would hate to have to recompile the POV firmware every time we want to change the fraze.
Now, we are still trying to figure out what we are going to need for this project, how to design and manufacture the circuit boards, write the firm- and software for the microcontroller and computer interface, and to come up with a working mechanical solution.
We don’t even have all the required tools, I still need to buy a new multimeter after my last one got stolen many years ago, and I’m also considering to buy a second hand oscilloscope to measure the signals in case we run into some problems.
More news follows when we have more information about how we are going to realise this.