Abstract: In a resistive planar graphic device, conductor strips are divided into two segments and corner resistances interconnect outer ends of the conductor strips which extend in spaced relationship along the edges of a rectangular resistive area and which are connected by edge connecting and isolating resistances to the edges of the rectangular area. The corner resistances are selected to improve the linearity of voltage gradients in the rectangular area.

Abstract: The frequency capability of a planar multiple switch for entry of digital data is improved by forming an upper conductive planar member from fine conductive elements electrically joined, such as a screen or conductor pattern, together but with sufficient space between elements to substantially reduce capacitive coupling between the upper member and lower contact members. Further, multiple bit switch areas are formed adjacent single bit switch areas; and coded contact areas are formed on parallel lines by placing insulation on selected sections of lines and building up adjacent contact sections by additional conductor material.