Abstract: The invention relates to an integrated optical polarization splitter based on the mode filter principle, in which the asymmetry, necessary therefor, of the waveguides is obtained by using a polable glassy polymer as optical waveguide material, which material is polarization-sensitive in the poled state and is not, or virtually not polarization-sensitive in the unpoled state. A Y-shaped optical waveguide pattern 8 of polable glassy polymer comprises a continuous optical waveguide formed by the optical waveguide sections 8.1 (incoming) and 8.2 (outgoing) in which the polymer is in the unpoled state and an outgoing optical waveguide section 8.3 which connects to said optical waveguide at an acute angle and in a tapered fashion and in which the polymer is in the poled state. Since the poled material is also electro-optical, an electric field, for example generated between electrodes 2 and 10, can still correct any small deviations in the asymmetry.