Abstract: The present disclosure describes an optical waveguide device and a method for making such device. The device comprises a substrate; a waveguide embedded in the substrate, the waveguide having a refractive index higher than the refractive index of the substrate; and first and second optical mirrors placed respectively in two different positions along the waveguide. The method comprises steps of (a) cleaning a substrate by means of a cleaning agent; (b) embedding a waveguide in the substrate; and (c) placing first and second optical mirrors respectively at two different positions in the substrate, the steps (b) and (c) being performed in such a manner that the mirrors being positioned along the waveguide.