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What should be a properties of a body so a contact with it can be detected by a capacitive touchscreen or a touchpad?

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Not sure this passes the "too basic" criteria, can be answered from Wikipedia surely? Vote to close. – Alasdair Allan Nov 3 '10 at 15:24
Wikipedia is too basic here; I'm pretty sure someone in topic could elaborate a lot more. – mbq Nov 3 '10 at 15:34
up vote 2 down vote accepted

This reference from Wikipedia seems like a good place to start. See

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According to the wikipedia article, capacitative sensors detect things with conductive or dielectric properties; so to me, that means these sensors detect a contrast in the electrical properties between your finger, say, and the air around it.

I just tested this out on my touchpad with a metal ruler and if I pushed down, I got a little bit of response.

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Try whit glass an report – ralu Nov 3 '10 at 22:23
I tried with a wooden chopstick and nothing happened. – j.c. Nov 4 '10 at 9:51
This reference from Wikipedia seems good. See… – sigoldberg1 Nov 4 '10 at 16:19
@sigoldberg1 Post it as an answer so I could accept it. – mbq Nov 10 '10 at 16:28

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