Abstract: Selected touch point locating apparatus has an array of two or more electrical touch members constituted by impedance elements coupled to a circuit for causing electric current to flow through a selected touch point as the algebraic sum of separate currents through the electrical touch members. The relative amplitudes are translated into at least two signals corresponding to the location in two axes of the selected touch point.

Abstract: Selected touch point locating apparatus has an array of two or more electrical touch members constituted by conductive electrodes or impedance elements coupled to a circuit for causing electric current to flow through a selected touch point as the algebraic sum of separate currents through the electrical touch members. The relative amplitudes are translated into at least two signals corresponding to the location in two axes of the selected touch point.

Abstract: A method and apparatus for calculating the growth interacting substance potency and growth ratio for the intersections of a scanning spot with a track of visible microbial colonies on an interaction plate. The potency is a measure of the weight of a growth interacting substance which is deposited on the interaction plate per unit volume of the growth culture medium. The growth ratio is a measure of the growth interacting substance effect on growth of colonies of microbes on the interaction plate along the path of interaction of the scanning spot with visible microbial colonies.

Abstract: A hand-held electronic musical instrument and system has a plurality of resistance elements that have adjacent thereto indentations or notches, or other tactile structures for locating discrete notes. Each resistance element is connected to a circuit for translating the position of the musician's finger on the element into an electrical signal, the frequency of the signal corresponding to the position touched. Transducers convert the electrical signals into sounds, which are modified by an acoustic cavity within the instrument. At least one control panel is provided on a side of the instrument engaged by the thumb or thumbs of the musician, each control panel also being a one-dimensional touch panel with the control axis perpendicular to the long axis of the panel so that the musician's thumb can slide along the panel parallel to the long axis without changing its position in the control axis. The musician controls the volume of the sound by adjusting the position of the thumb transverse to the instrument.

Abstract: Edge terminations for polygonal impedance or resistance surfaces provide linearization of current flow to and/or from the surface through electrical connections at the vertices of the polygon. The edge terminations are constituted by a series of parallel ranks or rows of connective segments overlaid, inlaid or printed at each edge of the polygonal surface with the innermost row or rank being short straight segments and the length of each segment of the next innermost row, respectively, being longer. The central segment in each row or rank is electrically interconnected with the central segments in the other rows. A guard plane of conductive metal insulated from the impedance or resistance surface is also provided.

Abstract: A general method is disclosed for accurately determining the location or position of a source or sink of electric current on the surface of a resistance element or impedance layer. Touch panels are described that detect the presence of a user's finger on such surface, and produce output signals corresponding to the position of the finger in one or more axes. A preferred embodiment discloses a touch panel that includes a signal generator and determines the position of the user's finger from current flowing through the user's body to ground. Another touch panel embodiment determines the position of the user's finger from currents caused by ambient electrical noise. A pressure-sensitive touch panel, a transparent touch panel for use with a video display, a touch-panel-controlled audio mixer, and a video game incorporating touch panels are also disclosed.

Abstract: A video game apparatus and method in which two-axis output signals are produced when a surface activated with X-Y excitation signals is touched by the human finger. The control surface has a configuration corresponding to the play area on the video display. The device has the ability to sense the presence or absence of the user's finger, as well as intensity of touch or pressure, thus adding further dimensions of control since the presence of the user's finger on the control surface can be used to activate the video display and present the user's playing implement, if that be the case, on the screen wherever it is touched to introduce a further element of surprise and excitement into the playing of video games.

Abstract: A general method is disclosed for accurately determining the location or position of a source or sink of electric current on the surface of a resistance element or impedance layer. Touch panels are described that detect the presence of a user's finger on such surface, and produce output signals corresponding to the position of the finger in one or more axes. A preferred embodiment discloses a touch panel that includes a signal generator and determines the position of the user's finger from current flowing through the user's body to ground. Another touch panel embodiment determines the position of the user's finger from currents caused by ambient electrical noise. A pressure-sensitive touch panel, a transparent touch panel for use with a video display, a touch-panel-controlled audio mixer, and a video game incorporating touch panels are also disclosed.

Abstract: A system is described for coupling two voltage sources to a resistive plane, surface or layer so as to produce a uniform electric field in said plane with orthogonal components along the two axes of the plane generated by the two voltage sources so that coordinates of position of a digit or finger in the field may be determined. Techniques are described for fabricating both the plane and the coupling elements from the same resistive material. It is also shown how nonlinear electric fields can be created while preserving orthogonality. Three-dimensional fields of predetermined characteristics can be created by extending the techniques to curved surfaces and by using multiple surfaces.

Abstract: A human-machine interface apparatus includes a first, or phase, surface with associated circuitry so devised that an alternating electrical field is created above the surface with its phase, relative to a fixed point on the surface, changing continuously along an axis of the surface; a second, or pickup, surface located so that when the operator of the interface apparatus inserts a finger in the field an electrical signal with phase corresponding to the point of insertion is transmitted through the operator's body to the pickup surface; and a phase discriminator with one input connected to the pickup surface and a reference input connected to an alternating voltage source of predetermined phase relationship to the alternating electrical field at a fixed point on the phase surface. The preferred embodiment combines two such apparatuses, sharing common phase and pickup surfaces but operating at different frequencies, to provide outputs corresponding to two orthogonal axes on the phase surface.

Abstract: A human-machine interface apparatus includes a first, or phase, surface with associated circuitry so devised that an alternating electrical field is created above the surface with its phase, relative to a fixed point on the surface, changing continuously along an axis of the surface; a second, or pickup, surface located so that when the operator of the interface apparatus touches the phase surface an electrical signal with phase corresponding to the spot touched is transmitted through the operator's body to the pickup surface; and a phase discriminator with one input connected to the pickup surface and a reference input connected to an alternating voltage source of predetermined phase relationship to the alternating electrical field at a fixed point on the phase surface. The preferred embodiment combines two such apparatuses, sharing common phase and pickup surfaces but operating at different frequencies, to provide outputs corresponding to two orthogonal axes on the phase surface.