[Nexus 7 Q&A, Help & Troubleshooting] Bifurcator:
Any progress?

I think it's almost impossible for it to be the fault of the screen protector. But there are many kinds of touch screens and if the Nexus7 just happens to be using some hybrid that needs pressure then it's certainly possible.

Think of CTS screens (almost) as proximity sensors. They can actually sense (you) from around a foot away quite easily. As the distance decreases the "signal strength" increases. If we apply an arbitrary numerical value to that signal strength it /might/ look something like:

9 inches - 0.01

8 inches - 0.02

7 inches - 0.02

6 inches - 0.03

5 inches - 0.04

4 inches - 0.05

3 inches - 0.07

2 inches - 0.10

1 inches - 0.20

0.1 inches - 1.00

0.001 inches - 2.00

0" full contact - 10.00

But typically the software algorithms which determine whether a touch event has occurred or not imply a threshold value of (again arbitrary for the sake of example), 9.00. The dielectric properties of "the" plastics of interest for protectors and screens have been thoroughly examined and established AFAIK. They do disperse the electrical force somewhat via factors such as air-space between the protector layer and the screen, whatever insulating impurities may be present in the protector material, the material's own molecular structure, and etc. The amount of electrical field dispersion or distortion that occurs through the material is a function of the materials thickness in the case of the materials commonly being used. Maybe you can imagine looking at a flashlight through murky/milky water where the closer you get the stronger the signal and the more clarity (of the source) can be distinguished. Where this "strength/clarity" begins to become a problem for software "touch" detection is usually around 5mm or 6mm (of commonly used material) between your fingertip and the sensor. If different materials are used this distance changes and can change radically. In keeping with my photovoltaic example, if the material in question could act like a tight bundle of optical fibers (only of course conducting electricity and not light) then the "protective" material could be meters thick without being detrimental to the registration of a touch event.

This is why i think it's almost impossible for it to be the fault of the protector... But everything factor's in. Body weight, blood iron content, protector material impurities, humidity (RH), temperature, skin moisture, variations in the Earth's electrical field from area to area and over time, material thickness, the software algorithm's threshold values, and so on. If they all come together in just the wrong way you could experience the touch registration intermittence you are describing - for sure. And with millions and millions of sensor screens being manufactured it could also be faulty connections there too but /that/ would be my very last guess as they really are ultra-simply constructed. If it's charging at all it should (famous last words) work equally across the entire surface area.

---------- Post added at 01:20 AM ---------- Previous post was at 12:58 AM ----------

Have a look at that poll thread tho:

http://xdaforums.com/poll.php?do=showresults&pollid=9771

416 people report screen separation and almost 130 people report touch-screen malfunction.

That's pretty radical! Maybe it's time to ditch Nexus7 all together?