How to make a big transparent touch sensor?

I would like to make a big cube for an art project that if you touch one side of it, an arduino would sense it an then turn on a light inside.

I have played with capacitive touch sensors but the are usually small and would require the user to touch in a small target area. Also when the cube illuminates, that part would block light (not a huge deal).

Is there any easy way to make a capacitive touch sensor out of transparent material that could cover the whole side?

It is acting like a switch and not trying to locate X-Y.

basically I am trying to make a giant illuminated pushbutton.

Any ideas???

thanks!

Here's a cheesey idea :slight_smile:

bounce a laser back and forth closely together so you can detect when a finger tries to pass through the "plane". Could just be in open air:

getting the mirrors parallel enough and everything lined up will be tricky.

Use a the capacitive touch sensor idea only make the sensor the metal frame of a fish tank. Any touch on the glass walls will give you enough change to detect and turn your light on.

I saw a video where someone had three large aluminium plates at right angles and they superimposed a 3D image to give an imagined touch. That was done with an Arduino.