Hi all, I've been researching about how to make a touch sensor, the circuit itself is relatively easy, there are tons of ICs that can make this possible ranging from 555 timer to ATMEL AT42QT1010. (I've chosen atmel).

However, how about the sense electrode? I understand touching any copper plate will do, you can even cover it will any non-conductive material, but how they make this thing possible (image in attachment), how the electrode sense the touch from the glass alone?

I appreciate the help a lot! This is basically the only thing that I'm stuck with

 

Either it uses a large electrode in the base that extends the sensing range, or a transparent conductive coating- Indium Tin Oxide, for example, on the plastic.

http://www.indium.com/inorganic-compounds/indium-compounds/indium-tin-oxide/

 

Either it uses a large electrode in the base that extends the sensing range, or a transparent conductive coating- Indium Tin Oxide, for example, on the plastic.

http://www.indium.com/inorganic-compounds/indium-compounds/indium-tin-oxide/

are there any research papers regarding electrode size and sensing range? I'm just trying to make this touch sensor lamp for fun, using a special conductive coating sounds like too sophisticated, or maybe I should go for other designs for the touch sensor lamp already

 

You will find the (not very special) answer to your question in this ebay listing....

http://www.ebay.co.uk/itm/Creative-...d-Gift-/201652953529?var=&hash=item74a33872ac

 

Use ultra thin wires - almost invisible.

 

You will find the (not very special) answer to your question in this ebay listing....

http://www.ebay.co.uk/itm/Creative-...d-Gift-/201652953529?var=&hash=item74a33872ac

Thanks! I bought the sensor lamp myself awhile ago, they really used the vibration sensor, we actually need to smack it for the lamp to detect the vibration. Thanks again for the answer