An optical waveguide that performs both in-coupling and out-coupling using two diffractive optical elements is provided. Each optical element is a diffraction grating and can be applied to the same or different surface of the optical waveguide. The diffraction gratings overlap to form two overlapping regions. The first overlapping region in-couples light into the waveguide and the second overlapping region out-couples light from the optical waveguide. Because the optical waveguide only uses two gratings, and therefore only has two grating vectors, the optical waveguide is easier to manufacture than optical waveguides with a greater number of grating vectors.

An apparatus includes an input radio frequency waveguide. The apparatus includes a radio-frequency-to-optical-radio-frequency-impedance-matching interface communicating with the input radio frequency waveguide. The apparatus includes a plurality of optical modulators communicating with the radio-frequency-to-optical-radio-frequency-impedance-matching interface. The apparatus includes a plurality of respective optical waveguides communicating with the plurality of optical modulators. The plurality of respective optical waveguides in operation includes a plurality of respective optical waveguide fields. The input radio frequency waveguide in operation includes an input radio frequency waveguide field. The input radio frequency waveguide field interacts with the plurality of respective optical waveguide fields to convert an input radio frequency signal into a plurality of optical signals.

A photonics integrated device for coupling radiation using flood illumination is disclosed. The photonic integrated device comprises an integrated waveguide, a coupler grating at the surface of the device for coupling radiation from said flood illumination towards the integrated waveguide, and a grating for blocking, reflecting or redirecting radiation away from the coupler grating at the surface of the device. The grating for blocking, reflecting or redirecting radiation away from the coupler grating thereby is positioned relative to the coupler grating so as to prevent at least some radiation from said flood illumination, impinging at the grating for blocking, reflecting or redirecting radiation away from the coupler grating and thus impinging at a position of said surface away from the coupling grating, from being reflected within the device towards the coupler grating.

An optical device includes an array of optical grating couplers and a plurality of single-core fiber couplers located over a planar substrate. The optical grating couplers of the array are located to optically couple in a one-to-one manner to optical cores of a multi-core fiber or optical cable having an end located adjacent to the surface. Each single-core fiber coupler includes a planar optical waveguide connecting a corresponding one of the optical couplers of the array to an edge of the substrate.

An integrated optical coupler device comprising, on a substrate surface: an integrated optical coupling grating extending in lateral directions parallel to the substrate surface and which, by diffraction at its grating structures, either converts electromagnetic waves, guided parallel to the substrate surface, of at least two waveguide modes of integrated optical waveguides into fiber modes propagating perpendicularly to the substrate surface, or converts electromagnetic waves, propagating perpendicularly to the substrate surface, of a fiber mode into electromagnetic waves, propagating parallel to the substrate surface, of at least two waveguide modes, and a first conductor pair, connected to the coupling grating and formed by a first and a second integrated optical waveguide, through which, in mutually opposite first and second directions parallel to the substrate surface, electromagnetic waves of at least two waveguide modes can be conducted to the coupling grating or can be conducted away from the coupling grating.

A wavelength division multiplexer is disclosed. The wavelength division multiplexer may include an input waveguide, in which a plurality of Bragg gratings for separating multiplexed optical signals into respective optical signals are provided, and a plurality of output waveguides connected to the input waveguide and configured to receive the optical signals separated by the plurality of Bragg gratings. The plurality of Bragg gratings may include a first Bragg grating including first protrusions each having a first width, and a second Bragg grating including second protrusions each having a second width larger than the first width. Each of the first and second protrusions may include a curved side surface, to which a corresponding one of the optical signals is incident.

An optical display system and an augmented reality electronic device are disclosed. The optical display system comprises: a waveguide; an input coupler, provided at the input end of the waveguide and couples an image light into it; and a two-dimensional grating, provided at the output end of waveguide. The waveguide delivers the image light to the two-dimensional grating, which performs pupil expansion on the image light and out-couples the expanded image light. The two-dimensional grating has rhombus lattices. Unit cells of the two-dimensional grating are un-symmetric along respective axes parallel with a propagation direction of the image light incident onto the two-dimensional grating, from a top view of the two-dimensional grating. The unit cells are oriented with the propagation direction of the image light and each of the unit cells has at least two vertexes at its end side.

An object of the present disclosure is to provide an optical side input/output circuit for allowing light for being input into or output from a side surface of an optical fiber with high efficiency.

The present disclosure is an optical side input/output circuit including: a tap unit in which a tap waveguide is formed for allowing light for propagation through a core of an optical fiber for being input into or output from a side surface of the optical fiber; and a refractive index matching unit, having a refractive index higher than a refractive index of the tap waveguide, on the side surface of the optical fiber where the light is allowed for being input or output by the tap waveguide.

An optoelectronic integrated circuit for coupling light to or from an optical waveguide formed in an optical device layer in a near-normal angle to that layer. In an embodiment, the integrated circuit comprises a semiconductor body including a metal-dielectric stack, an optical device layer, a buried oxide layer and a semiconductor substrate arranged in series between first and second opposite sides of the semiconductor body. At least one optical waveguide is formed in the optical device layer for guiding light in a defined plane in that device layer. Diffractive coupling elements are disposed in the optical device layer to couple light from the waveguide toward the second surface of the semiconductor body at a near-normal angle to the defined plane in the optical device layer. In an embodiment, an optical fiber is positioned against the semiconductor body for receiving the light from the coupling elements.

An optoelectronic integrated circuit for coupling light to or from an optical waveguide formed in an optical device layer in a near-normal angle to that layer. In an embodiment, the integrated circuit comprises a semiconductor body including a metal-dielectric stack, an optical device layer, a buried oxide layer and a semiconductor substrate arranged in series between first and second opposite sides of the semiconductor body. At least one optical waveguide is formed in the optical device layer for guiding light in a defined plane in that device layer. Diffractive coupling elements are disposed in the optical device layer to couple light from the waveguide toward the second surface of the semiconductor body at a near-normal angle to the defined plane in the optical device layer. In an embodiment, an optical fiber is positioned against the semiconductor body for receiving the light from the coupling elements.