A recent patent filing by Apple has come to light, and it discusses a touch-based input system that would enable "unprecedented integration of typing, resting, pointing, scrolling, 3D manipulation, and handwriting into a versatile, ergonomic computer input device."

AppleInsider calls the filing further evidence of Apple's oft-rumored tablet device, while a PC World blog says it's simply "a new kind of keyboard and mouse combo, not an oversized iPod Touch," which is how the Apple tablet has been described by many web sites, including AppleInsider. Apple's patent filings are made public just like any other patent filings, but they're usually cryptic enough that it's not clear how, or even if, they'll eventually be used.

In this case, the patent explains: "Many attempts have been made to embed pointing devices in a keyboard so the hands do not have to leave typing position to access the pointing device . . . The limited movement range and resolution of these devices, leads to poorer pointing speed and accuracy than a mouse, and they add mechanical complexity to keyboard construction."

Given the fact that the patent describes the user placing both hands on the input device and performing specific tasks through combinations of fingers -- called "chords" in the filing -- it seems that PC World is closer to being on the right track, since placing both hands on a tablet device would obscure nearly the entire screen. (Apple's device is rumored to have a 10-inch screen.)

However, as with all of Apple's patent filings, this particular one must be taken with a very large grain of salt. It could describe functionality that will be used in a way not envisioned by either web site, and there's no guarantee the technology will even emerge from Apple's R&D labs.