Abstract: A method for producing a desired resistive taper under computer control for controlling the surface resistivity of an electrical element, which comprises the steps of creating a computer controlled optically graded pattern corresponding to the desired resistive taper, producing a phototool from the graded pattern and using the phototool to photochemically etch the graded pattern onto a substrate.

Abstract: A sensor and method for identifying the surface properties of a workpiece includes a microstrip sensor for transmitting and receiving microwave signals and surface properties determining means for determining the surface properties of the workpiece, including the type of material from which the workpiece is constructed, based upon the strength of the detected microwave signals. The surface properties identifying sensor also includes a microwave generator for producing microwave signals at a predetermined frequency for transmission by the microstrip sensor and a detector for detecting the microwave signals received by the microstrip sensor from the workpiece. Thus, workpieces comprised of a conductive material, an insulative material and a conductive material coated with a radar absorbing material can be readily distinguished by the surface properties identifying sensor and method.