Scriptel Corporation

Scriptel Holding, Inc.

Robert G Kable

Philip A Schlosser

Shoichiro Nakamura

Shiochiro Nakamura

The electrographic apparatus of a variety wherein a transparent resistive layer is deposited upon an insulative substrate in a manner wherein a rectangularly-shaped resistive layer region is developed having a predetermined conductivity. A conduction band is provided about the periphery of the resistive layer region having a value of conductivity enhanced with respect to the conductivity value of the resistive layer. Discrete resistive elements are positioned intermediate the conduction band and the resistive region and four terminals are provided, one at each of the four corners of the rectangular resistance region. The discrete resistance elements are designed so that a uniform impedance is witnessed with respect to the resistive layer region as witnessed with respect to each of the four terminals. The control system for the device provides for development of coordinate pair information and includes as non-volatile memory retained configurational data for initial set-up of the apparatus by the operator.

Electrographic apparatus

An improved tracer for use with electrographic surfaces which employs reticle components including crosshairs and a sighting circle which additionally functions to provide capacitive coupling. Formed of a conductive material such as chromium, these components are geometric regular shape and somewhat concentrated at the center portion of the reticle targeting center. As such, the device is capable of achieving a close correspondence between actual physical targeting location and resultant digitized coordinate readout. These components further achieve an avoidance of inaccuracies due to active surface border influences. The reticle-capacitive coupling components are placed on one side of a transparent disk, the opposite or upwardly disposed surface of which is coated with a transparent electrically conductive material such as indium tin oxide. This upwardly disposed conductive layer is coupled with ground and there results a dissipation of spurious signals which otherwise may influence the performance of the device.

Tracer for electrographic surfaces

A stylus for use with an electrographic system of a variety wherein a digitizer surface is excited. The stylus accomplishes capacitive coupling with the surface without distortion due to perpendicular orientation of its central axis with respect to the digitizer surface. Due to the employment of a carefully shielded signal transmission rod in conjunction with a conductive body wall, spurious noise developed through the body and hand of the user is avoided. A switching technique wherein the stylus is depressed into the digitizer surface is provided, preferably employing a Hall effect switching device.

Stylus for position responsive apparatus having electrographic

A position responsive apparatus, system and method which employs a position responsive surface formed of two orthogonally disposed arrays of grid elements which in one embodiment, the elements are coupled along one border with a resistor chain or the equivalent which is excited with an a.c. source at terminal locations. Capacitive coupling between the orthogonally disposed arrays at the cross-over locations of grid elements is significantly reduced by reducing the area of the grid elements at the cross-over positions. Further, intermediate grounding terminals serve to minimize disruptive potentials caused by the capacitive coupling. The control for the system employs a procedure wherein a correction look-up table is developed as part of the manufacture of the apparatus wherein readings are taken at the nodal points of communication between the grid array and the resistor chain and which then are treated to provide a regularly incremented sequence of address values developed from a signal domain computation. Physical domain coordinate values are correspondingly derived and are located in the table with each address value. The control for the embodiment accesses this memory for purpose of developing corrected coordinate outputs, thus eliminating the need for precise calibration of each resistor within the resistor chain. The invention further contemplates the employment of transparent grid array elements. Significant improvements to performance are achieved by exciting these elements from resistor chains located and coupled therewith at oppositely disposed ends of the grid elements. An improved switching approach is provided wherein excitation currents are employed at the switching stage which then are applied to voltage follower stages for coupling with the grid array terminal.

Position responsive apparatus, system and method having electrographic

An electrographic apparatus or digitizer has a resistive layer with an active area which operates in conjunction with a stylus or other suitable position locator. An a.c. source or alternatively a signal treatment means is connected to the resistive layer through rows of electrodes and position coordinates of the position locator are developed by the apparatus. Voids or discontinuities are formed in the resistive layer to increase the edge-to-edge resistance of the layer and to provide identical edge-to-edge resistances in the x- and the y-coordinate direction for digitizers which are rectangular and non-square.

An electrographic system and method having a control which carries out correction for graphic surface non-linearities. The control employs a procedure wherein a correction look-up table is developed as part of the manufacture of the device wherein output readings are taken along a physical domain rectangular grid array of predetermined dimension and these output readings are adjusted in their signal domain to establish a regularly incremented sequence of address values within that signal domain. Physical domain coordinate values then are derived and placed in the table for each address value. The control then accesses this memory for each of a given locator or tracer position on the graphic surface and carries out an interpolative weighting to derive acceptably accurate coordinate pair signals which are outputted to a host computer or the like.

Electrographic system and method

An electrographic apparatus and system utilizing a resistive layer having an active area which operates in conjunction with a stylus or tracer or other suitable position locator. An a.c. source or alternatively a signal treatment means is connected to the resistive layer through rows of electrodes. Improved accuracy is achieved through the use of electrodes at the ends of the electrode rows and through the use of an enhanced conductivity region which also allows the boundary of the active area to be placed in close proximity to the electrodes.

An electrographic apparatus utilizing a resistive layer which operates in conjunction with a stylus or tracer. Either the resistive layer or the cursor may be excited from an a.c. source to develop coordinate-defining electrical signals. A sequence of border switching arrays is provided which minimizes the number of switching components required for any given resistive layer or tablet architecture. Improved accuracy is achieved through an automatic gain control and gain election procedure as well as through the imposition of a positive offset signal and a control technique wherein the offset values of the circuit are cyclically evaluated and the coordinate data information is adjusted in accordance with that evaluation.

Growing community of inventors

Dublin, OH, United States of America

Robert G Kable