ITO-coated glass with a measured sheet resistance of just over 20 ohms is conductive enough to build a functional touch-sensitive button, and that is exactly what maker Sokol demonstrates on YouTube.
The build skips the obvious capacitive approach. Instead, two pieces of ITO glass are placed with their conductive sides facing each other, separated by a paper spacer. Pressing the glass flexes it enough to bridge the two ITO surfaces and complete the circuit, exactly how resistive touchscreens resolve finger position by measuring resistance between two conductive layers.
The part worth reading closely is the implication: this same two-pane sandwich, combined with firmware that samples resistance at multiple points, could yield a DIY multi-position touch surface built entirely from commodity glass. Sokol's video shows the proof-of-concept working. The scaling question is open.
[READ ORIGINAL →]