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(I'm new to EE.SE, so I don't know if this is on-topic here. Please forgive me.)

From what I understand, capacitive touch technology relies on coating one side of a resistive material with a conductor; this conductor is usually indium tin oxide, and the resistive material is almost always glass or some substance based on glass.

Why can't the resistive material be replaced with a thermoplastic, such as PMMA/acrylic or polycarbonate? Surely, that would make the panel quite a bit stronger than the glass-based panels that are used. Edit: This is definitely possible.

If this is possible, why don't any manufacturers produce plastic-based projected capacitive touch panels? (Or is there one that does, and I just haven't come across it?)

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    \$\begingroup\$ I've just Googled plastic touch panel . Now I wonder if you've done that before asking "why not?" \$\endgroup\$ – Nick Alexeev Jan 21 '13 at 1:11
  • \$\begingroup\$ @NickAlexeev Everything I found was either not an actual product (eg. technical demonstrations), highly specialized (eg. very low-resolution PCT grids for large displays; Samsung's flexible AMOLED mobile display prototypes), or resistive. \$\endgroup\$ – Tortoise Jan 21 '13 at 1:15
  • \$\begingroup\$ I've found papers such as this one claiming that this can exist, but I haven't found any actual manufacturers of these types of panels. I'm too lazy to figure out how to apply ITO to a piece of plastic in a grid and use it to measure capacitance in an integrated device with Linux drivers myself, so I was kind of looking for something I could actually obtain and use. \$\endgroup\$ – Tortoise Jan 21 '13 at 1:17
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The normal process for applying ITO is vapor deposition: like 'fogging' a mirror with steam, but using a boiling metal alloy. The challenge in doing that with thermoplastic would be not melting it in the process. (There are some references on google to doing this at room temperature with a plasma instead, though).

Recent advances in glass hardness mean that 'gorilla' glass screens are much less prone to scratching and chipping than acrylic (which in my experience scratches almost immediately). They are more brittle rather than flexible, but as long as the screen isn't bent that's not an issue.

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