Simplified touch tablet data device
A touch tablet is provided containing two sheets of insulating material
each of which contains a plurality of spaced apart conductive lines. A
resistive strip on each sheet contacts and connects electrically one end
of each of the plurality of conductive lines on that sheet. Each resistive
strip functions as a potentiometer. Mounted between the two sheets and
spaced apart therefrom is a conductive middle sheet. The first and second
sheets are mounted such that the first and second sets of a plurality of
conductive lines on these sheets are orthogonal to each other. A user
presses on one of the two sheets to bring all three sheets into contact.
The impedence of each potentiometer is a function of the contact point.
The potentiometer is used as part of an RC circuit to provide a variable
time constant representative of the coordinate of the contact point.
Thornburg; David D. (Los Altos, CA), White, III; George M. (Los Altos, CA) |
Koala Technologies Corporation
March 15, 1983|
Sears; C. N.