Abstract: A process for the manufacturing a fiber optic depolarizer as well as an arrangement of that type uses two optical fiber sections which obtain the polarization planes of the light and which are connected with one another in such a manner that the principal axes of the optical fiber sections enclose an angle of 45.degree.. An optical fiber piece which obtains no polarization is inserted between the optical fiber sections whose principal axes enclose an angle of 45.degree., in that the optical fiber sections and the optical fiber piece are fixed to one another at their connecting areas. The principal axis orientations of the optical fiber sections are adjusted in such a manner that, in the case of a firm positioning of one of the two connecting areas by the torsional twisting of the other connecting area, an angle of 45.degree. is adjusted.

Abstract: The protective cladding for a mono-mode directional coupler made of at least two incoming and outgoing fiber optic waveguides which are fused to one another along a coupling segment comprises at least two open cladding parts which can be connected to form a tube-shaped cladding. The material of the cladding parts has the same coefficient of expansion as the waveguide material of the mono-mode directional coupler. The protective cladding, being mechanically tightly connected with the incoming and outgoing fiber optic waveguides while leaving open the coupling segment of the mono-mode directional coupler, is closed off in a gas-tight manner such that in the case of temperature changes, there are no mechanical tensions in the coupling segment.

Abstract: A sagnac-type fiber optic gyroscope in which depolarizers are connected to both ends of the fiber coil and are then connected with the outputs of a 3.times.3 directional coupler.

Abstract: A Sagnac-type fiber optic gyro having a control and analysis unit which controls the intensity and the center wave length of the light emitted from the light source in such a manner that the ratio of the output signal of the light detector to the output signal of its monitoring detector is constant.

Abstract: A laser diode is provided having a strip-shaped web based on the principle of a metal clad ridge waveguide laser diode with a strip-shaped web width of less than 10 .mu.m. At least one lateral web extends laterally of the strip-shaped web and serves as a carrier for an electrical connection between the metal cladding of the strip-shaped web and a contacting surface for an electrical lead.