The invention relates to a coupling device comprising a support substrate; a first layer arranged on the support substrate and comprising first patterns produced within the thickness of said first layer, said first patterns being arranged in parallel and periodic rows; a second layer arranged on the first layer and comprising second patterns passing through the thickness of said second layer, said second patterns being arranged in parallel and periodic rows. The direction of periodicity of the rows of the first patterns is perpendicular to the direction of periodicity of the rows of the second patterns. The rows of the first patterns extend over a distance greater than or equal to the wavelength in the void of the optical wave intended to be coupled. The first patterns have a width less than or equal to a tenth of the wavelength of the optical wave intended to be coupled, and the period of these patterns is between 50 nm and 1 μm. The second patterns are arranged so as to form a periodic diffraction grating.