Abstract: The invention relates to an optical polarization regulator having a wave-guide structure for converting the polarization state of an optical beam passing through and comprising devices for adjusting the coupling constants K of the TE and TM modes of the optical beam and for adjusting the difference .DELTA..beta. of the propagation constants .beta..sub.TE and .beta..sub.TM of these modes. The wave-guide structure is a magnetooptical element (8, 9, 13). The coupling constant K is adjusted by a magnetic field acting upon the wave-guide structure (8, 9, 13) and the difference .DELTA..beta. is adjusted by a mechanical deformation force exerted on the wave-guide structure.

Abstract: The invention relates to a magnetooptical waveguide device for the conversion of modes of propagation of the device. The device comprises layers (1, 4, 5, 6, 7) which are epitaxially applied to a substrate layer (8) and of which at least the waveguide layer (1) in which the modes propagate consists of a transparent magnetooptical material for which mode conversion can be induced by a magnetic field. For more accurate matching of the phase velocity of the TE and TM modes this structure is disposed in an apparatus (14, 15) by which an adjustable mechanical deformation force (24, 25) is exerted on the wave guide structure.