proximity sensor?

I'm looking to make a pair of something that light up when near each other--say a foot or two. Is what i'm looking for a proximity sensor, or is there some simpler solution to this?

[edit] Could I use a set of rf transmitters and receivers to turn on the light in each object without having to program anything?

Thanks in advance,

10player


Goodhart8 years ago
It might depend on what you mean by "light up".  Incandescent bulbs?  LEDs?  Paint  in special light?  

If the "light" is / are LED(s), then an infrared detector would probably be the easiest. Actually, come to think of it, that is true of regular light bulbs too.

Sensing presence, is normally done by sensing motion,  but if you mean one thing that senses only the other of the pair; then there are a lot of options.
 
10player (author)  Goodhart8 years ago
" but if you mean one thing that senses only the other of the pair; then there are a lot of options."

Ah, that's what I was trying to say :\ haha. And, sorry for not including in the original post, I did mean LED's also >.<