I think it's the same type of technology a laptop touchpad or a ipod clickwheel uses you know. Something to do with your finger affecting the capacitance of it.
It's pretty neat that they've got it work on a screen.
I've always wondered why other objects didn't work on the iPhone (gloves, pointing devices, finger nails). I was never able to explain to people, that you need to use your finger tip when operating the iPhone. I thought it was due to the iPhone touch screen needing a larger surface area for input detection. Recently, over the last few weeks... I've began to notice that the fingers I use to interact with the iPhone are beginning to tingle here and there... also.... when I use the iPhone I swear I can feel a small tingling sensation. So I theorized that the screen is conductive or senses heat...
I tested this theory and tried it out on multiple fingers... and I wrote it off as it being in my head. Also... the fact that I placed a membrane to protect the screen caused me to believe that the touch screen can't be conductive.
After some more time... I still feel tingly sensations in my index finger, so I googled for a bit and I haven't been able to find really credible facts, but I did find a post that stated "The iPhone touchscreen works using electrical conductivity, not pressure" (SOURCE: http://www.jasonsantamaria.com/archive/2007/01/14/a_plea_for_the_fatfingered.php). I was unaware of this and would explain why my finger is feeling funny.
My question to the BOL Forum is "How does the iPhone touch screen exactly work?" What are the specifics (current etc), are there any long term effects (tingling, numbness)??? Thanks for any light you all can shed on this for me!!!
Deigratia (Jazzman)

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