OPTICAL LIGHT WAVEGUIDE SWITCHING ELEMENT, AND SWITCHING MATRIX COMPOSED OF A MULTITUDE OF SUCH AN ELEMENT

An optical switching element including two parallel optical guides G1 and G2 each constituted by a strip of a semiconductor material having a refractive index n1 formed on a semiconductor substrate having a lower refractive index n0, the switching operation being obtained by the effect of voltages applied to electrodes arranged in the switching zone, characterized in that the latter is constituted by a strip of the same semiconductor material as the guides, which extends between the latter over a coupling length D between the abscissae -D/2 and +D/2 indicated on the orientated longitudinal axis of symmetry, and in that the electrodes are at least three in number, of which a first electrode permits of applying a reference voltage to the substrate, a second electrode extends substantially at the surface of the second guide from the abscissa -D to the abscissa - epsilon , epsilon being small with respect to D, and a third electrode extends substantially at the surface of the first guide from the abscissa + epsilon to the abscissa +D, the second and third electrodes forming strips whose longitudinal axes of symmetry enclose with the optical axes of the second and first guides, respectively, an angle - theta defined on first approximation by the relation: theta 2 APPROX 2(n1-n0)/n1.