The present invention provides an electro-optical device, characterized in that it comprises two plane optical substrates (100) each having at least one optical waveguide (110), and a nematic liquid crystal (200) inserted between them, in which the liquid crystal (200) is split into two separate active zones (210, 220) serving to control coupling/decoupling of a respective one of the TE and TM polarizations of a light signal injected into the waveguides (110).