Abstract: In a device for measuring the movements of a person's eye there are one or more sets of cooperating light detecting elements and light emitting elements intended primarily for measuring in chosen selected directions. Each set could consist of two light detecting elements located at a distance on each side of the eye and symmetrically with respect to the eye and in a symmetry plane of the eye containing the direction chosen. The associated light emitting elements are located, also symmetrically, in a plane substantially orthogonal to the plane with the light detecting elements. When many sets of cooperating light emitting and detecting elements of this kind are combined into a symmetrical or semisymmetrical arrangement, this permits selecting, for an eye movement in a given direction, the most suitable set for detecting the eye movement in this direction. Only one set of light emitting elements, assigned to the axis of measurement, is active at a time.

Abstract: An arrangement for controlling the current in a circuit having a source of current connected with an inductive device and a load. A switching member is provided in the circuit, this member being controlled between on and off conditions by a triggering element joined to a series circuit which includes the inductive member, an additional inductance and a control member. The control member establishes the rate at which the additional inductance becomes saturated when the switching member is turned off. The state of saturation is employed to operate the switching member thereby controlling current flow to the load.