Wednesday, July 3, 2013

Visualizing Electromagnetic Fields


In yesterday's post I mentioned my interest in ham radio as a youngster.  I think part of the intrigue comes from the idea that there are these invisible fields around us all the time and they can be used to communicate information.  It seems like magic.  Some folks have been coming up with techniques to visualize this hidden world.  I like this idea.  The video above shows the electromagnetic fields around electronic devices by taking long exposure photos while moving an android phone configured as an electromagnetic field meter along the device in question.  It is a great technique and the results are informative and artistic.

Someone else did something similar with RFID below.  In this case they used a device that blinks whenever the RFID reader senses it.  The space it defines is the area in which the reader can sense an RFID (ie how close an RFID tag needs to be in order for the reader to sense it).