Method and device for generating an error signal in connection with coherent heterodyne reception of lightwaves

The invention relates to a method and device in for generating an error signal in connection with the coherent heterodyne reception of lightwaves. A device is used for generating error signals for regulating the optical alignment of two lightwaves in connection with coherent heterodyne reception and comprises a receiver device () arranged focused opposite a front face at the end of a lightwave fiber () in order to make possible the transmission of the received information lightwave through the lightwave fiber () to an optical waveguide coupler (), which is connected via a further lightwave fiber () with a local laser () and via two further lightwave fibers () with respectively one detector () for generating at least one error signal (Sr). A piezoelectric deflection unit () acts on this front face of the lightwave fiber () located in the focusing area of the receiving device.