Single Plane Tablet Using Resistive Wedges
Original Publication Date: 1982-Jan-01
Included in the Prior Art Database: 2005-Feb-08
A single-layer capacitive tablet in which electrodes provide capacitive coupling with a pen to produce signals which correspond to the X and Y dimensions of the position of the pen on the tablet is described in U.S. Patent 4,087,625. To achieve position signals for two orthogonal axes from one conductive pattern, one axis uses the geometry of wedge-shaped conductors to produce a variable coupling to the sensing pen and the other axis uses a conventional voltage gradient applied by a separate external voltage divider.