Abstract: A pressure sensitive transducer array in which a plurality of transducers are connected in series and in parallel with one another. In one embodiment, a resistive layer is formed from carbon or silver ink on a polyester film. A plurality of conductive shunt elements having greater conductivity than the resistive layer is formed on a second polyester film. The films are placed adjacent to one another with the shunt elements contacting the resistive layer. Voltage is applied across the resistive layer and pressure is applied thereto. As the pressure increases, the number of current paths set up through contact points on the shunt elements increase thereby decreasing the resistance across the resistive layer and increasing current flow. In another embodiment a plurality of plate elements are contained in a plane on one side of a dielectric layer. A plurality of plate elements are contained in a plane on the other side of the dielectric layer.

Abstract: Data acquisition in a multi-function keyboard system includes both acquiring typing data by conventional keyboard scanning techniques and, simultaneously, acquiring pointing data by sampling force sensors coupled to the multi-function pointing key. The keyboard system periodically samples the force sensors to determine bias values defining a null point, and updates the bias values by a moving average calculation to compensate for manufacturing tolerance and long term drift. In response to a start pointing command from the host processor, the keyboard system transmits bias values and then pointing values, the latter being responsive to forces applied to the pointing key by the user for cursor control. The sensor values are encoded so as to pass through to the host processor in a manner transparent to application software. The system scans the force sensors periodically to acquire successive pointing values, and transmits them to the host, as long as pointing mode persists.

Abstract: A computer system employs an integrated keyboard and pointing device to allow user input of alpha numeric (typing) information, pointing direction information and pointing event information without moving the user's hands from the usual typing position on the keyboard. The new system has typing and pointing modes of operation. In the pointing mode, preassigned keyswitches are used to input pointing events, cursor speed changes, and other modifications to the system's operation. All such modifications are transparent to the operating system and application software because they are processed at keyboard interrupt level.

Abstract: A keyswitch-integrated pointing assembly in which a plurality of substantially planar force sensing elements are disposed on a planar surface adjacent a keyswitch on a keyboard. The keyswitch includes a plunger which extends downwardly from a key cap for actuating a switch at the lower end of vertical key cap travel. The key cap engages an indexing surface when fully depressed which transmits force applied to the key cap to the force sensing elements. The force sensing elements are sandwiched between a pair of opposing plates thereby biasing the elements into a substantially linear operating region when no force is applied to the key cap.

Abstract: A computer system employs a keyboard that includes an integrated pointing device coupled to a pointing key. The system has a typing mode of operation and a pointing mode of operation. In the pointing mode, the pointing key is used to enter pointing information, thereby obviating a discrete pointing device such as a mouse. The system may be switched between the typing mode and the pointing mode explicitly by predetermined commands. Alternatively, the system may be switched into the pointing mode implicitly by monitoring and timing keyboard events following a pointing key press.

Abstract: A computer system employs an integrated keyboard and pointing device to allow user input of alpha-numeric (typing) information, pointing direction information and pointing event information without moving the users's hands from the usual typing position on the keyboard. The new system has typing and pointing modes of operation. In the pointing mode, preassigned keyswitches are used to input pointing events, cursor speed changes, and other modifications to the system's operation. All such modifications are transparent to the operating system and application software because they are processed at keyboard interrupt level.