Periscope assemblies are provided which have a light path that travels in a first plane along the first waveguide, a second plane along the second waveguide that is parallel to the first plane, and along a third plane along the third waveguide that intersects the first plane and the second plane. In some examples the periscope assembly includes first and second carriers comprising respective first and second waveguides and defining respective first and second cavities in which a third carrier comprising a third waveguide is disposed and optionally includes an optical component. In some examples, the cavities are defined in one or more carriers on a mating surface, on a side opposite to the mating surface, or on a side perpendicular to a mating surface.

An optical network having at least one star coupler comprising transmit and receive optical mixers which are respectively optically coupled to transmitters and receivers of a plurality of optical-electrical media converters. Each optical-electrical media converter comprises a respective receiver optically coupled to the receive optical mixer by way of plastic optical fibers and a respective transmitter optically coupled to the transmit optical mixer by way of plastic optical fibers. The output plastic optical fibers attached to an output face of the receive optical mixer have a diameter less than the diameter of the input plastic optical fibers attached to an input face of the receive optical mixer.

A graded index fiber having a refractive index profile that causes a beam to be re-imaged in the graded index fiber with a regular period may include a set of bends that have a bend period matched to or nearly matched to a pitch of the graded index fiber. For example, the set of bends may be formed in the graded index fiber using one or more bending devices that include one or more protrusions that have a periodicity matched to or nearly matched to a pitch of the graded index fiber. A first section of the one or more bending devices may be actuated to move towards a second section of the one or more bending devices such that the one or more protrusions cause the bends to be formed in the graded index fiber.

Provided is an optical coupler configured to cause an NA of light, which exits a taper fiber, to be smaller as compared with a conventional optical coupler. A taper fiber has a high refractive index part which is provided inside a core of the taper fiber and which has a refractive index smaller than a refractive index n.sub.core of the core. An exit end surface of each GI fiber is bonded to an entrance end surface of the taper fiber so that at least a part of the exit end surface of the each GI fiber overlaps with a section of the high refractive index part. A relative refractive index difference of the taper fiber is smaller than 0.076%.

A device for inserting a plurality of optical beams into a single-mode optical fibre, a guiding structure of which is composed of a core with a first refractive index, a cladding with a second refractive index, and a coating with a third refractive index. The device includes an optical mixer configured to insert, into the single-mode optical fibre, the plurality of optical beams, at least one of which has a distribution of its radial and angular electromagnetic amplitude with a maximum amplitude peak in the cladding.

A light source assembly having N outputs, the assembly including: a light source arrangement arranged for supplying light to M inputs, where M an N independently of each other are integers and where M≥2 and M≥N; at least one optical couplers, each having at least one input arm and a plurality of output arms; and an integer number, P, of mode scramblers. The light source arrangement may include a broadband light source and a multimode coupler configured for receiving one or more light beams from the light source arrangement, wherein the one or more light beams being derived from the broadband light source and wherein a mode scrambler is arranged for mode scrambling one of said light beams before it enters the multimode coupler.

An apparatus includes an optical transmitter having a plurality of optical data modulators and an end-face coupler. Each of the optical data modulators is configured to output a corresponding data-modulated optical carrier. The optical end-face coupler is configured to direct the data-modulated optical carriers into a pattern of light beams to illuminate an end-face of a multi-mode optical fiber with a pattern of light spots. The optical end-face coupler is configured to cause each of the data-modulated optical carriers to excite a set of orthonormal optical propagating modes of the multi-mode optical fiber. Some of the orthonormal optical propagating modes of the set have nontrivially differing intensity and/or phase profiles.

A device includes an optical splitter comprising a plurality of splitter outputs. The splitter outputs are out of phase and include a non-uniform phase front. The device includes a one-dimensional phase compensation array communicating with the optical splitter. The phase compensation array receives the non-uniform phase front and outputs a uniform phase front. The phase compensation array includes a plurality of array outputs. The device includes a tunable linear gradient phase shifter communicating with said phase compensation array to impart a linearly-varying phase shift across said plurality of array outputs, thereby steering a beam along a first angle in a first plane. The device includes a waveguide grating out-coupler communicating with said linear gradient phase shifter, and a uniform phase shifter communicating with the waveguide grating out-coupler. The uniform phase shifter steers the flat phase front along a second angle in a second plane perpendicular to said first plane.

An aspect of the disclosure provides for an optical-phased array (OPA) comprising a star coupler coupled to a plurality of grating couplers, wherein the star coupler comprises multiple inputs and multiple outputs. In some embodiments, each output of the star coupler is coupled to a grating coupler of the plurality of grating couplers. In some embodiments, the star coupler is coupled to the plurality of grating couplers by a plurality of optical delay lines. In some embodiments each output of the star coupler is coupled to a grating coupler of the plurality of grating couplers via an optical delay line of the plurality of optical delay lines. In some embodiments, the OPA further includes an optical switch coupled to the multiple inputs of the star coupler, and at least one tunable laser. Another aspect of the disclosure provides a method for steering light using the OPA.

A passive optical network includes a central office providing subscriber signals; a drop terminal; and a wave division multiplexer. A fiber distribution hub may split or separate out dedicated optical signals from subscriber optical signals between the central office and the drop terminal. The wave division multiplexer separates dedicated optical signals pertaining to a specific dedicated subscriber from other optical signals on the line received at the wave division multiplexer. The wave division multiplexer may be part of a cable or part of an intermediate service terminal.