3
\$\begingroup\$

I'm looking at touchscreen supplier specs such as this one.

What does the specification "touchpoint density" expressed as touches/sq.cm sq.in or mean? The value given is "> 100,000 touches/in^2". Does this mean it can differentiate between pinpoint touches at 100,000 points at every square inch?

\$\endgroup\$
1
\$\begingroup\$

In 1 square inch of touchscreen area, there are more than 100,000 distinguishable points. It doesn't mean it can distinguish between a touch at (0,0) and (1,0), but that the touchscreen controller could return 100,000 different points.

\$\endgroup\$
  • \$\begingroup\$ So, to clarify, since sqrt(100000) is about 316, the controller can return any coordinates from (0,0) to (316,316) in one square inch? \$\endgroup\$ – Jay Feb 29 '12 at 15:48
  • \$\begingroup\$ Be careful in general this resolution is a math exercise. The sensing methodology gives four signals which are used to calculate the center of touch which is reported. The number of points reported is more a function of how many "decimals" I include in the calculation. To borrow an ADC parallel, beware the ENOB of reported position. \$\endgroup\$ – naven87 Nov 22 '12 at 7:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.