We've had a glimpse at Apple's conception of a sensor-based keyless layout, and the latest patent application from Cupertino shows the company looking to further refine the input experience -- this time using a camera and other sensors to detect hand position and overlay that hand position on a device's screen. The filing details three methods to this end. The first shows a user's hands on a traditional hardware keyboard projected in an on-screen representation (as background, Apple mentions the ergonomic strain of looking down to check your hand placement, so perhaps that's the thinking behind this one). A second scenario involves a laptop with unlabeled keys, where the marked keyboard is displayed on the screen, and the final, most intriguing, setup shows backside controls on a tablet a la the PS Vita, with a user's fingers projected as if the device was transparent. Of course, this is just a patent application at this point, so don't expect to see this tech make its debut September 12th.