Planarer elektro-optischer Lichtstrahlablenker und Verfahren zu seiner Herstellung

The invention relates to a planar electro-optical light beam deflector comprising a row of adjacent prism deflectors equipped with electrodes to which an electrical voltage can be applied. A main feature of the invention is that the light beam is guided in a Z section lithium niobate or lithium tantalate crystal, preferably in a monomode layer optical waveguide extending along its surface, and the prism deflectors each consist of two triangular or prism-shaped regions in which a largely uniform polarization direction is formed by inverting the polarization direction determined by the E field vector in domaines where the spontaneous polarization direction opposes the present direction, whereby each of the neighbouring triangular-shaped regions has an opposing polarization direction, and that a square electrode covering the triangular regions is attached to the top side of the crystal and a counter-electrode is attached to the bottom side of the crystal. The measures according to the inv ention achieve the phenomenon that a refractive index with a different sign is induced in the adjacent triangular or prism-shaped regions when a voltage is applied between the electrode and the counter-electrode, whereby the distribution of refractive indices represents ideally almost a sawtooth pattern. The invention also relates to a process for the production of such a light beam deflector.