Abstract: A transparent coordinate input apparatus for an electrostatic capacity coupling system mounted on a CRT tube surface, an LCD display surface or the like to effect input. The transparent coordinate input apparatus comprises a tablet composed of a plurality of electrode wires arranged close to the display surface of the inptu device such as CRT, LCD, etc. and arranged in an axial direction of the axis of coordinate; a control section for sequentially applying pulse signals to the electrode wires of said tablet; a coordinate indication means electrostatic-capacity coupled to the pulse applied to each of the electrode wires of said tablet to effect signal detection; a calculation section for calculating a positional coordinate from the signal detected by said coordinate indication means, and a noise preventive means for relieving a noise from the display surface of the input device such as CRT, LCD, etc.

Abstract: A cursor device for a capacitive coupling tablet used as a digitizer for inputting a figure or pattern. An index indicative of a coordinate position on a tablet to be input is displayed on a pane mounted on a window of a housing, and on the side opposite the pane are carried a detection electrode corresponding to the index and a signal transmission wire extending from the electrode. The detection electrode is capacitively coupled to a few conductors adjacent to each other within the table to detect pulses having a level related to the distance from these conductors. In this case, the level of the pulse detected from the conductors present at a position crossed to the signal transmission wire tends to relatively lower, and therefore, a shield layer distributed around the electrode is formed on the pane to solve such inconveniences.

Abstract: Disclosed is a pattern input apparatus in which an input pen is made to be in contact with a tablet having a matrix composed of sets of conductors disposed at intervals along coordinate axes, thereby applying hand writing information to an electronic computer, or the like. In this pattern input apparatus, the input pen is made to be contact with or moved on the upper surface of the tablet to thereby obtain detection signals, the respective potential levels of at least three higher ones of the obtained detection signals being selected out, the detection signal having the highest potential level among the three selected out detection signals being regarded as a reference signal, subtraction being made between the reference signal and each of the remainder ones of the three selected out detection signals to obtain two potential differences, thereby determining the position of the pen on the basis of the ration between the two potential differences.