Patent ID: 7312788

Claim:
A gesture-based input device for a user interface of a computer comprising: two pairs of electrodes scalable for any screen size, wherein the electrodes are arranged to capture a quasi-electrostatic field surrounding a user in order for the user interface to provide different options or tasks to be selected by the user, a platform for supporting the user, a quasi-electrostatic field generator source connected to the platform; and a circuitry connected to the electrodes for determining, relative to each of the electrodes, a position of a part of the user being closest to electrodes, wherein the position of the part of the user in each dimension of the electrodes is determined based on a relation of four voltage signals of the circuitry, respectively, each voltage signal indicating a distance between the part of the user and the respective electrode, whereby the position within the electrode closest to the part of the user is determined without any calibration of a sensor system, and V H =  U O  L  U O  R V V =  U O  B  U O  T is utilized to cancel an environment effect and remove a calibration process before use of the input device by the user, and U o is the output signal from the correspondent electrode.