In our coverage of Nokia’s Lumia announcement this morning, we mentioned one demonstration the company did with the the 920, showing how its capacitive touch sensor worked even when the user was wearing bulky mittens. We usually think of capacitive sensors as requiring exposed skin to work, so what’s Nokia up to here?
We’ve talked a little about the different kind of capacitive sensors in the past, like when Sony introduced phones with its “floating touch” feature. The sensors at the heart of all these interfaces are a lot more flexible than we give them credit for, and are sometimes capable of detecting motion at a distance. In practice, manufacturers want to dial-down that sensitivity so it gives the illusion of requiring physical contact with the screen. That also lets them filter-out unintended inputs.
It’s not clear yet exactly what Nokia’s doing with the 920 and its so-called “Super Sensitive Touch” technology, but it sounds like a combination of increasing the sensitivity of the capacitive sensor in order to detect more motion at a distance, combined with improved software to weed-out stray inputs. That’s how it can still sense your finger through a glove. Other tricks, like the using a key to point with in the video below, are easily done with pretty much any smartphone (update: some of you are calling foul on this. Maybe try a different key, if the alloy’s an issue, but it works on all the capacitive displays I’ve tried. It seems to work better with more metal, so also try a keyring with additional keys on it – try a spoon if you don’t believe me) – the only question is if the screen’s tough enough not to get scratched.