Telegraphy – Systems – Position coordinate determination for writing
Patent
1976-07-30
1978-01-24
Robinson, Thomas A.
Telegraphy
Systems
Position coordinate determination for writing
G08C 2100
Patent
active
040705447
ABSTRACT:
Electrographic apparatus, that is apparatus for obtaining electrical signals related to the movement of a point, such as a pen or stylus, over a pressure sensitive surface, and a method of producing an electrode surface for such apparatus. The pressure sensitive surface is formed by the upper surface of a taut flexible membrane. Two generally parallel electrode surfaces are formed by electrically conductive coatings on the lower surface of the flexible membrane and on an upper surface of a backing member so that pressure applied to the pressure sensitive surface locally interconnects the electrode surfaces. In use, voltages are applied orthogonally to the respective electrode surfaces so that the potentials developed at points on the surfaces correspond to the X and Y coordinates of those points. The method of forming such an electrode surface comprises the steps of forming the coating so as to have a region of high resistivity traversed by parallel lines of low resistivity, the lines being interconnected by film resistor tracks, and selectively removing portions of the film material of the resistor tracks to provide uniform potential gradients between adjacent pairs of the lines when a voltage is applied to the electrode surface. The membrane is substantially uniformly tensioned by springs, and the upper surface of the backing member is concave so that the force required to be applied to the membrane to cause the membrane to contact the upper surface of the backing member is substantially independent of the location at which the force is applied.
REFERENCES:
patent: 2597674 (1952-05-01), Robbins
patent: 3480728 (1969-11-01), Chandler
patent: 3885097 (1975-05-01), Pobgee
patent: 3921165 (1975-11-01), Dym
Quest Automation Limited
Robinson Thomas A.
LandOfFree
Electrographic apparatus and method of producing an electrode su does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrographic apparatus and method of producing an electrode su, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrographic apparatus and method of producing an electrode su will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-489370