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by piyush_soni 3224 days ago
Is there some more information on that? I believed so far (or the industry made me believe) that capacitive screens were much faster than the resistive ones.
2 comments

I don't have like, hard tested data. But the delay is enough that experience was all I needed to convince me.

Nintendo DS / 3DS and Wii U are all resistive screens. I also have experience with resistive screens of Palm Pilot and Palm phones of the early 2000s. And all of those were more "responsive" than a 2007-era iPhone, despite the iPhone's significantly higher processing power.

Play a serious game like Monster Hunter (very timing intensive) and compare it to a serious timing-intensive game on a capacitive screen (I know I've seen people play Marvel vs Capcom 2 on an iPhone emulator...). The lag and delay is noticeable even in the modern era.

But people wanted multi-touch pinch to zoom. Capacitive sensing also requires a microcontroller to literally "charge up" the screen over and over.

When your finger is on the screen, it "charges up slower" (because your finger changes the capacitance at that location). Innately, that "charge and discharge" cycle requires a measurement over time.

And to make sure that power isn't wasted, only one part of the screen is often tested (there are grids and stuff that then calculate where the fingers or multiple-fingers are located). So innately, there's a delay as the "scan-lines" of the sensors test each point of the screen.

Resistive screens instantly tell you where the stylus is without any such delay or processing. So it just makes sense.

I don't have any direct links, but the latency on processing touch input from a capacitive display can be as high as 40ms, remember there is a lot of filtering going on and spurious crap that has to be filtered out.

Think how crazy the trackpad goes on a cheap laptop when you plug in a knock-off power supply with poor power conditioning.