Planar nanophotonic waveguide comprising a structure for optical coupling with an optical fibre

摘要

The nanophotonic monomode planar waveguide comprises an optical core (16), an optical cladding (18, 20) covering the core, a structure for coupling the core of waveguide with a core of monomode optical fiber, and a prism (40) that includes first and second flat sides and is arranged on the optical cladding. The coupling structure comprises an adjustment element including a progressive widening of the core of waveguide of which an end is adapted with the core of the optical fiber through a wider region, and a light transmission element that is optically connected with the wider region. The nanophotonic monomode planar waveguide comprises an optical core (16), an optical cladding (18, 20) covering the core, a structure for coupling the core of waveguide with a core of monomode optical fiber, and a prism (40) that includes first and second flat sides and is arranged on the optical cladding. The coupling structure comprises an adjustment element including a progressive widening of the core of waveguide of which an end is adapted with the core of the optical fiber through a wider region, and a light transmission element that is optically connected with the wider region and defines a flat coupling surface (34) through which the light is transmitted to the optical fiber. A rate of optical coupling through the coupling surface is the maximum for a predetermined coupling angle of light with respect to the coupling surface, when the surface is contacted with air. The first flat side is arranged on or in contact with the coupling surface, and the second flat side is designed to optically cooperate with the optical fiber, where the sides are separated from each other at an angle whose value is equal to an angle of refraction (theta p) in the prism. The light transmission element comprises periodic slits formed on a side of the wider region. The second side of the prism inscribes a terminal section of the optical fiber with which the second side of the prism is designed to be optically connected. The prism and a portion of the optical cladding have same refractive index and are made of same material such as silicon. An independent claim is included for an optical coupling system.