An optical device has two optical waveguides embedded in a clad. The optical waveguides are mutually parallel and are separated by a distance that allows optical coupling between them. The optical waveguides have identical square cross sectional shapes in a plane orthogonal to the direction of light propagation, so that light propagates through each optical waveguide without polarization dependence. The length of each side of the square cross section of the optical waveguides is determined from the refractive index of the clad and the distance between the longitudinal axes of the optical waveguides so that coupling between the two optical waveguides is also polarization independent for light with a wavelength of 1.49 micrometers, which is the longer of the two wavelengths used in optical subscriber networks.