Patent ID: 7295744

Claim:
A frequency-selective light coupler-decoupler device comprising a component of photonic crystal structure constituted by a plurality of dielectric elements with periodic spatial distribution, and in which a waveguide having rows of said dielectric elements extending along its longitudinal edges is formed by an absence of at least one row of said dielectric elements and/or by an offset between rows of said dielectric elements on either side of the waveguide, wherein, on at least one of said longitudinal edges, the number of rows of said dielectric elements is reduced so as to define a thin edge of the waveguide and form coupling zones between the waveguide and the outside of the photonic crystal structure for coupling frequencies, each zone enabling a component at a frequency corresponding to a light signal propagating in the fundamental mode of the waveguide to be extracted from the waveguide through its thin edge and/or enabling a component at said frequency of a light signal to be injected into said waveguide through its thin edge, the coupling frequencies lying in a photonic band gap or MSB of the waveguide and being defined by variations in dimensional parameters of the waveguide and/or of the photonic crystal structure between the ends of the waveguide.