Abstract: A force-sensing data input device of very high accuracy and a method for operating such a force-sensing input device. An input surface is provided having a transparent faceplate which conforms to the display surface of a display device, such as a cathode-ray tube display, with which the input device is used. A flange of the input surface is separated from a rigid, conductive reference surface or frame by force-sensing piezoelectric transducers, preferably constructed of lead-zirconium titanate. At least portions of the piezoelectric transducers which are sensitive to electromagnetic interference are located within wells formed in the frame so as to be shielded. Preferably, four piezoelectric transducers are provided, one at each corner of a rectangular opening formed in the frame. To determine the point of application of force on the input surface, the outputs of the four transducers are first summed.

Abstract: A controller is provided for manually actuated movement of a cursor in an interactive display wherein overshoot in the positioning of the cursor when rapid movement is involved is compensated employing a factor involving the user's reaction time and the motion rate of the cursor.

Abstract: A display apparatus may be constructed by imparting motion to the light from a small light source to give the appearance of a line, causing the light to be "off" and "on" as desired during traverse of a line length, using as many light sources as needed for a two-dimensional display and precorrecting the light timing to compensate for the apparent change in movement rate during the motion.

Abstract: A display system includes an oscillating mirror for deflecting modulated optical energy. The system includes apparatus for indicating when the mirror has reached its travel end point in both directions. Images are written during mirror travel in one direction between said end points, and synchronizing apparatus is provided to allow an image to be written during mirror travel in a direction opposite said one direction in such a fashion that the images written during both directions of mirror travel are superimposed on each other. Apparatus is provided to measure the time elapsed between cessation of writing during mirror travel in one direction, and the time the mirror reaches the end point of its travel in that direction. A second time period is measured out, beginning from the time the mirror reaches its travel end point, and production of modulated optical energy is allowed to proceed at the completion of the second time period which is made equal to the measured first time period.