Electrographic apparatus
First Claim
1. Apparatus of a type wherein a surface is selectively accessed with respect to positional data, comprising:
- an insulative substrate;
a resistive layer supported upon said substrate having an operational region extending within an operational periphery of predetermined geometric pattern and configured to exhibit predetermined values of conductivity and resistivity;
said operational periphery being spaced inwardly from an outer boundary;
mutually spaced terminals supported upon said substrate positioned adjacent said outer boundary and the corners of said geometric pattern;
means defining a conduction band exhibiting enhanced conductivity with respect to said operational region conductivity supported upon said substrate intermediate said outer boundary and said operational periphery;
a plurality of spaced, discrete resistance elements, each in electrical communcation intermediate said conduction band and said resistive layer and each having a resistance value selected to effect exhibition of a substantially uniform electrical impedance of said layer to each said terminal;
an excitation signal source;
a ground reference;
swich means actuable for applying said ground reference to first select ones of said terminals while, simultaneously applying said excitation signal source to second ones of said terminals oppositely disposed from said first ones; and
control means for actuating said switch means to effect derivation of positional data modes.
21 Assignments
0 Petitions
Accused Products
Abstract
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.
-
Citations
42 Claims
-
1. Apparatus of a type wherein a surface is selectively accessed with respect to positional data, comprising:
-
an insulative substrate; a resistive layer supported upon said substrate having an operational region extending within an operational periphery of predetermined geometric pattern and configured to exhibit predetermined values of conductivity and resistivity;
said operational periphery being spaced inwardly from an outer boundary;mutually spaced terminals supported upon said substrate positioned adjacent said outer boundary and the corners of said geometric pattern; means defining a conduction band exhibiting enhanced conductivity with respect to said operational region conductivity supported upon said substrate intermediate said outer boundary and said operational periphery; a plurality of spaced, discrete resistance elements, each in electrical communcation intermediate said conduction band and said resistive layer and each having a resistance value selected to effect exhibition of a substantially uniform electrical impedance of said layer to each said terminal; an excitation signal source; a ground reference; swich means actuable for applying said ground reference to first select ones of said terminals while, simultaneously applying said excitation signal source to second ones of said terminals oppositely disposed from said first ones; and control means for actuating said switch means to effect derivation of positional data modes. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. Apparatus of a type wherein a surface is selectively accessed with respect to positional data, comprising:
-
an insulative substrate; a resistive layer supported upon said substrate having an operational region extending within an operational periphery of predetermined geometric pattern and configured to exhibit predetermined values of conductivity and resistivity, said operational periphery being spaced inwardly from an outer boundary; mutually spaced terminals supported upon said substrate and positioned adjacent said outer boundary and the corners of said predetermined geometric pattern to develop positional data modes; means defining a conduction band exhibiting enhanced conductivity with respect to said operational region conductivity, supported upon said substrate intermediate said outer boundary and said operational periphery; a plurality of spaced discrete resistance elements, each in electrical communication intermediate said conduction band and said resistive layer and each having a resistance of value selected to effect exhibition of a substantially uniform electrical impedance of said layer to each said terminal; a time varying excitation signal source for providing a first signal at a first select frequency and a secon signal at a second select frequency; switch means actuable for applying said first signal to first select ones of said terminals while, simultaneously, applying said second signal to second select ones of said terminals oppositely disposed from said first ones; and control means for actuating said switch means to effect derivation of said positional data modes. - View Dependent Claims (13, 14, 15, 16)
-
-
17. Electrographic apparatus, comprising:
-
an insulative substrate; a resistive layer supported upon said insulative substrate and extending in an x-coordinate sense between first parallel, spaced-apart borders and in a y-coordinate sense between second parallel, spaced-apart border to provide a rectangular resistive layer region having four corners and configured to exhibit predetermined values of resistivity and conductivity, said resistive layer region being spaced inwardly from an outer boundary; a terminal supported upon said substrate adjacent said outer boundary for interaction with said resistive layer region at each said corner; means defining an elongate conduction band exhibiting predetermined enhanced conductivity with respect to said conductivity of said resistive layer region, supported upon said substrate intermediate said outer boundary and said first and second parallel, spaced-apart borders; a plurality of discrete, spaced resistance elements, each in electrical communication intermediate said conduction band and said resistive layer region and each having a value of resistance selected to effect exhibition of a substantially uniform electrical impendance of said region to each said terminal an excitation signal source; a ground reference; switch means coupled with said terminals, said source and said ground reference and actuable to selectively apply said excitation signal and ground reference to said terminals; locator means movable into adjacency with said resistive layer for reacting therewith to develop position signals; and control means for actuating said switch means during a first data mode to apply said ground reference and excitation signal to first and second pairs of said terminals selected in said x-coordinate sense and, to apply said ground reference and excitation signal to third and fourth pairs. of said terminals selected in said y-coordinate sense during a second data mode, and including signal treatment means responsive to said position signals derived during said first and second data modes for deriving respective x-coordinate and y-coordinate signals. - View Dependent Claims (18, 19, 20, 21, 22)
-
-
23. Electrographic apparatus, comprising:
-
an insulative substrate; a resistive layer supported upon said insulative substrate and extending in an x-coordinate sense between first parallel, spaced-apart borders and in a y-coordinate sense between second parallel, spaced-apart borders to provide a rectangular resistive layer region having four corners and configured to exhibit predetermined values of resistivity and conductivity, said resistive layer region being spaced inwardly from an outer boundary; a terminal supported upon said substrate adjacent said outer boundary for interaction with said resistive layer region at each said corner; means defining an elongate conduction band exhibiting enhanced conductivity with respect to said conductivity of said resistive layer region, supported upon said substrate intermediate said outer boundary and said first and second parallel, spaced-apart borders; a plurality of discrete, spaced resistive elements, each in electrical communication intermediate said conduction band and said resistive layer region and each having a value of resistance selected to effect exhibition of a substantially uniform electrical impedance of said region with respect to each said terminal; an excitation signal source deriving a first signal at a first select frequency and a second signal at a second select frequency; switch means coupled with said terminals and said source and actuable to selectively apply said first and second excitation signals to said terminals; control means for actuating said switch means during a first data mode to apply said first and second signals to first and second pairs of said terminals selected in said x-coordinate sense and to apply said first and second signals to third and fourth pairs of said terminals selected in said y-coordinate sense during a second data mode, and including signal treatment means responsive to said position signals derived during said first and second data modes for deriving respective x-coordinate and y-coordinate signals. - View Dependent Claims (24, 25, 26, 27, 28)
-
-
29. Apparatus of a type wherein a surface is selectively accessed with respect to positional data, comprising:
-
an insulative substrate; a resistive layer supported upon said substrate having an operational region extending within an operational periphery of predetermined geometric pattern and configured to exhibit predetermined values of conductivity and resistivity;
said operational periphery being spaced inwardly from an outer boundary;mutually spaced terminals supported upon said substrate, positioned adjacent said outer boundary the corners of said geometric pattern; means defining an elongate conduction band exhibiting enhanced conductivity with respect to said operational region conductivity supported upon said substrate intermediate said outer boundary and said operational periphery; a plurality of spaced, discrete resistance elements, each in electrical communication intermediate said conduction band and said resistive layer and each having a resistance of value selected to effect exhibition of a substantially uniform electrical impedance of said layer to each said terminal; an excitation signal source; locator means coupled with said excitation signal source and movable into contacting adjacency with said resistive layer for applying said source thereto at a select location; current to voltage converter means coupled with each said terminal, exhibiting a virtual ground thereto and having position output signals in response to said source application by said locator means; switch means actuable for collecting select said position output signals in accordance with predetermined positional data modes; and control means for actuating said switch means in accordance with said data modes and for treating said collected position output signals to derive x- and y-coordinate signals corresponding with said locator means select location. - View Dependent Claims (30, 31, 32)
-
-
33. Electrographic apparatus, comprising:
-
an insulative substrate; a resistive layer supported upon said insulative substrate and extending in an x-coordinate sense between first parallel, spaced-apart borders and in a y-coordinate sense between second parallel, spaced-apart borders to provide a rectangular resistive layer region having four corners and configured to exhibit predetermined values of resistivity and conductivity, said resistive layer region being spaced inwardly from an outer boundary; a terminal supported upon said substrate adjacent said outer boundary for interaction with said resistive layer region at each said corner; means defining an elongate conduction band exhibiting enhanced conductivity with respect to said conductivity of said resistive layer region, supported upon said substrate intermediate said outer boundary and said first and second parallel, spaced-apart borders; a plurality of discrete, spaced resistance elements, each in electrical communication intermediate said conduction band and said resistive layer region and each having a value of resistance selected to effect exhibition of a substantially uniform electrical impendance of said region to each said terminal; an excitation signal source; locator means coupled with said excitation signal source and movable into adjacency with said resistive layer for reacting in signal transfer relationship therewith at a select location; current to voltage converter means coupled with each said terminal, exhibiting a virtual ground thereto and having position output signals in response to said locator means reaction; switch means actuable for collecting select said position output signals; and control means for actuating said switch means during a first data mode to effect collection of said position output signals from first and second pairs of said terminals selected in said x-coordinate sense and to effect collection of said position output signals from third and fourth pairs of said terminals selected in said y-coordinate sense during a second data mode, and including signal treatment means responsive to said collected position signals derived during said first and second data modes for deriving respective x-coordiante and y-corrdiante signals. - View Dependent Claims (34, 35, 36)
-
-
37. A digitizer tablet of a variety wherein an electrically active surface is accessed by a locator to effect the generation of coordinate pair signals which are converted to coordinate pair digital values by a signal treatment circuit and wherein a microprocessor having memory converts said digital values to digital outputs in correspondence with operator selected received configuration parameters, the improvement comprising:
-
a readout mounted upon said tablet for observation by said operator; a menu signal region designated upon said active surface and accessible in signal transfer relationship by said locator; said memory retaining said configuration parameters including mode of operation, scale units and coordiante speed; said microprocessor being responsive to said signal tranfer at said menu signal region for effecting a menu selection display at said readout for prompting said operator to select derived said configuration parameters by select movement of said locator upon said active surface.
-
-
38. The method for converting voltage gradient distortion from rectilinearity in an electrographic device formed of an insulative substrate supporting a resistive layer of rectangular shape within a predetermined periphery of parallel borders, said layer exhibiting predetermined resistivity and corresponding conductivity and having access terminals at each corner of said rectangualr shape comprising the steps of:
-
providing four elongate narrow conduction bands of conductivity enhanced by ratio of at least 10;
1 with respect to the said conductivity of said resistive layer, substantially parallel with and in spaced adjacency from each said resistive layer parallel border and in electrical communication with adjacent said terminals; andproviding a plurality of discrete, spaced resistive components intermediate each said conduction band and an adjacent said parallel border, each said resistive component having a resistance value selected such that the impedances witnessed between each and the said terminal closest thereto are substantially equal. - View Dependent Claims (39, 40, 41, 42)
-
Specification