System and method for accurate detection of an input device liftoff

Various systems and methods are used for lift-off detection. There may be used a beam triangulation, and in one embodiment an optical liftoff detection module of the optical tracking module is disconnected. In one embodiment, a capacitive liftoff detection technique is used. A capacitor is built into the bottom casing of the mouse. If the mouse is resting on a surface, the surface material serving as a dielectric for the capacitor, while air acts as a dielectric when the mouse is lifted off. This change in the dielectric leads to a change in the capacitance value, resulting in detection of lifting. In one embodiment, a capacitor with a slightly compressible material is interposed between the two electrodes may be used. In another embodiment, a mechanical piston is used with an elastic membrane for the off-hook detection. The lift-off detection can be adjustable and / or customized. Instead of simple on-off notifications the actual amount of lift can be detected.