Abstract: The invention relates to polyol formulations containing fillers, to polyurethanes produced therefrom, to components having said polyurethanes containing fillers, and to a method for producing the components, in particular using spray technology.

Abstract: Heterodyne optical time domain reflectometer (OTDR) for determining the attenuation behavior of a monomode waveguide (test waveguide) by measurement of the backscattered parts of light pulses transmitted in said waveguide. An acousto-optic modulator (AOM) which deflects the transmission beam from a laser into the waveguide to be tested at a light frequency which is modulated with the acoustic frequency when the AOM is acoustically energized in a pulse mode. The light pulses backscattered from the test waveguide are superimposed on a local oscillator beam (LO) constituted by the laser beam which traverses the AOM when the AOM is not energized. The optical system losses are reduced in that the superposition is realized in a passive coupler, particularly a fibre coupler (10, 26).

Abstract: An optical multi-port element with an acousto-optical modulator (AOM) has at least two monomode optical waveguide connections, at one side thereof. The end surfaces of the waveguides disposed in the focal plane of a lens situated between the optical waveguides and the acousto-optical modulator. In order to obtain a construction which can be adjusted in a simple manner and which has low attenuation, with a small overall length, it is provided that at least one side of the AOM (1) a single lens (2,3,31) is disposed with its optical axis aligned to the transmission axis of the AOM (1), and that the optical wave-guides (4 to 6, 18 to 20 or 27,28) are disposed with their axes parallel to one another and spaced from the optical axis of the lens (2,3,31) in such a manner that parallel beams (14 to 17), leading from the lens (2,3,31) to the AOM (1), are directed to the active region of the AOM (1) at the Bragg angle to the optical axis.

Abstract: The invention relates to a polarization scrambler comprising a controllable optical phase retardation element for retarding with respect to one another components of a light beam with a different state of polarization, the light beam propagating through the element, and a control arrangement for controlling the phase retardation element, said control arrangement being adapted to supply a control signal so that as a function of time the phase retardation is controlled in such a way that with a given state of polarization (SOP) of the light entering the polarization scrambler varying states of polarization occur at its output in such a way that, averaged in time, the light intensities emerging in each SOP are at least substantially equal.