Abstract: A switching device comprises a swinging element (1) that is able to move between two end positions (A, B). Holding electrodes (4, 5) are placed in end positions (4, 5). A control circuit (8) controls the switching by generating signals of suitable voltage. Swinging element (1) is attached in an elastic manner (for example, by a flexible rod 2) in such a way that the elastic return force which tends toward a zero position (0) has, in an essential amplitude range, a higher value than the electrostatic force of attraction created by the control circuit and holding electrodes (4, 5) and acts in the opposite direction, in such a way that the switching time of the swinging element is determined primarily by its natural frequency and not by the magnitude of the electrostatic force of attraction.

Abstract: An optical device utilizing white light interferometry, having a Fabry-Perot interferometer incorporated in a reference branch of the optical device. The succession of interference products occurs from a combination of the light traveling through the transmission branch with the light traveling through the reference branch which has undergone 0 to N+1 reflections in the Fabry-Perot interferometer. The interference product gives a series of equally spaced absolute marks.

Abstract: The present invention relates to a process of coupling optical fibers by means of a holographic lens, and an apparatus for carrying out this process. A holographic lens H.sub.2 is recorded conventionally by utilization of a provisional hologram H.sub.1, by means of two monomodal optical fibers mounted by their respective end pieces in a block used to support the holographic lens. The block has bores, clearly defined in shape and position, into which are introduced the end pieces of monomodal fibers to effect recording of the holographic lens, and in which are fixed the end pieces of multimodal fibers which are to be optically coupled after withdrawal of the monomodal fibers. The process and apparatus of the invention enables the speckling phenomenon, i.e., that of non-uniform distribution of light in the transmitted beams, to be suppressed, improving the efficiency of the holographic lens.