Abstract: A mouse is provided that uses a camera as its input sensor. A real-time vision algorithm determines the six degree-of-freedom mouse posture, consisting of 2D motion, tilt in the forward/back and left/right axes, rotation of the mouse about its vertical axis, and some limited height sensing. Thus, a familiar 2D device can be extended for three-dimensional manipulation, while remaining suitable for standard 2D Graphical User Interface tasks. The invention includes techniques for mouse functionality, 3D manipulation, navigating large 2D spaces, and using the camera for lightweight scanning tasks.

Abstract: This invention describes a method and apparatus for filtering noise from a measurement of the X and Y coordinates of a resistive digitizer. The method applies to both four and five wire resistive digitizers biased with a DC voltage. The same filtering and measurement apparatus can be used on both types of digitizers with inclusion of an extra signal pin to accommodate the sense lead of the five wire digitizer. This approach involves connecting the signal to be read to a filter, reading the filtered voltage, and disconnecting the signal from the filter before disconnecting bias voltage from the planes of the digitizer. A separate filter is used for the X and Y coordinate signals and each filter voltage can be read at any time before the next measurement. A reset voltage is available to an established reference on the filter capacitor when a “pen up” status is detected.