Abstract: The method and the device are intended to measure the geometrical characteristics of components of optical communication systems comprising a body (1) with nominally cylindrical external surface and an internal element (2) nominally coaxial with body (1). The component is placed in a V-groove (3) and rotated by 360.degree.. A TV-camera (8) detects the curve (4) described by a point of the internal element during the rotation. Numerical analysis of the curve provides, by a single operation, eccentricity of the internal element and non-circularity of the external surface of the body. (FIG.

Abstract: A branched light-transmission network includes at least one body with a plurality of light-reflecting surfaces meeting in a common point or edge for illumination by a primary light guide, such as a light-conducting filament or foil, emitting a beam which is split among these surfaces into several components directed toward respective secondary light guides. Each reflecting surface is part of an optical system forming two conjugate points respectively coinciding with the centers of the proximal ends of the primary and secondary light guides emitting and collecting the rays reflected by that surface. These conjugate points may be the foci of an ellipse partly defined by the intersection of the reflecting surface with the common axial plane of the associated light guides; alternatively, they are the focal points of two lenses of positive refractivity which define paths of parallel light rays impinging upon and departing from the flat reflecting surface.

Abstract: Several monochromatic light beams of different wavelengths, modulated with respective message signals, are combined at a transmitting station into a composite beam conveyed via a fiber-optical path to a receiving station where the composite beam is resolved into its constituent beams. The mixing and separation of individual beams takes place with the aid of bodies each consisting of two transparent portions whose refractive indices vary as a function of wavelength along curves of different slope intersecting in a common point; a monochromatic beam whose wavelength corresponds to that point passes undeflected through the boundary of these portions whereas the beam or beams of larger wavelength, for which the complement of the critical angle of incidence equals or exceeds the glancing angle, are internally reflected to fall into line with the undeflected beam upon mixing and to deviate therefrom upon separation.

Abstract: Signals, especially short pulses, are transmitted by way of a series of light guides with internally reflecting boundaries (i.e. fibers or foils) angularly adjoining one another, each junction being encased in an external body having the same index of refraction as the light guides. Within the body the light rays exiting from one guide are intercepted by one or two mirrors reflecting them to the other guide, each mirror having a cross-section in the form of a segment of an ellipse whose foci are the center points of the two guide ends in a common axial plane of the guides. Each segment terminates in two points represented by the intersection of a respective guide axis with the path of a limiting ray from the other guide.