Abstract: In a method of producing a device having at least one optical waveguide on a substrate, two transparent layers are formed one on top of the other on the substrate. The material of the two layers is selected so that the melting point of the material of the second layer is lower than that of the material of the first layer, but has a higher refractive index than the first layer. After formation of the structure, a heating process is performed in which the material of the second layer melts and, due to surface tension, its surface, when seen in cross section, takes on the shape at least approximating the arc of a circle. With this cross-sectional shape, coupling of light waves into and out of an optical fiber is possible at one edge of the substrate after the end faces of the optical waveguide have been ground or polished.