Abstract: Control in the positioning of a computer mouse is improved by adding a finely adjusted frictional force component to relative motion in the plane of the mouse-supporting surface, or mouse pad, system. The added frictional force component operates to produce a drag component that dampens the movement. The added frictional force component may be provided by additional small localized weight increments, the effect of a magnetic field, or a change in coefficient of friction between parts that move in relation to each other, as examples.

Abstract: In electrical circuitry, and particularly superconducting circuitry including Josephson tunnelling devices, it is often necessary to provide solder contacts to electrical lines, where the electical lines would be destroyed if there were interdiffusion between the lines and the solder. To avoid this problem, a laterally extending metallic layer is used as a diffusion barrier between the solder land and the electrical line which can be a superconducting line. The diffusion barrier is comprised of a refractory metal which has a first portion electrically contacting the solder land and a second, laterally displaced portion, electrically contacting the electrical line. An insulating protective layer on the diffusion barrier layer separates the solder land and the electrical line.