By AppleInsider Staff

Published: 12:00 PM EST

Apple Computer in its research and development labs is experimenting with a variety of touch-screen technologies, recent patent filings have revealed.

The latest filing surfaced late last week, describing a virtual input device placement on a touch-screen user interface. Based on the visual diagrams associated with the filing, Apple appears to be working on several methods of displaying a virtual keyboard as part of the Mac OS X interface, which would allow users to type and input data without the use of a physical keyboard.

Virtual keyboard

In the filing, made Sept. 16, 2005, Apple said the technology includes "an application display, associated with an application executing on the computer, and a virtual input device display for a user to provide input to the application executing on the computer via the touch screen."

"In response to a virtual input device initiation event, initial characteristics of the virtual input device display are determined," the filing goes on to read. "Based on characteristics of the application display and the characteristics of the virtual input device display, initial characteristics of a composite display image are determined including the application display and the virtual input device display. The composite image is caused to be displayed on the touch screen."

Illustrations included with the patent filing reveal several different approaches Apple could use to integrate the virtual keyboard into the Mac OS. The first shows the keyboard merging upward from the base of the display to accommodate the bottom half of the touch-screen display, overlaying the Mac OS and application interfaces, which remain unchanged.

Similarly, a second and third approach describes example touch screen displays where the spatial aspect of the application display is modified in accommodation of the virtual keyboard. In one example, the entire Mac OS interface is shifted upwards, cropping the top half of the the Mac OS interface to allow room for the keyboard. Another example skews the Mac OS interface to fit entirely above the virtual keyboard without cropping.

Yet another approach portrayed in the illustrations is a partial pop-up virtual keyboard, which floats above the Mac OS interface in balloon-help window.

The patent filing is credited to three Apple software engineers, Imran Chaudhri, Greg Christie and Bas Ording.

Virtual click-wheel

Earlier this month, another touch-screen Apple patent filing surfaced, which describes "Gestures for touch sensitive input devices." Unlike the most recent filing, visual diagrams associated with this patent request feature illustrations of a hand using a touch-screen click-wheel controller on a PDA-sized device.

The patent states that "the invention relates, in one embodiment, to a computer implemented method for processing touch inputs... the method includes reading data from a touch sensitive device having a multipoint capability. The method also includes identifying at least one multipoint gesture based on the data from the touch sensitive device."

Some design aspects covered in the patent include a touch-screen device's ability to rotate, zoom, pan, page turn, and make scroll wheel, inertia, and floating control sequence actions, among others.

A detailed description of the invention stated that "the invention generally pertains to gestures and methods of implementing gestures with touch sensitive devices." Examples of touch sensitive devices include touch screens and touch pads, Apple said in the filing.