A light source unit generates an optical signal out of a bend-insensitive (“BI”) optical fiber that is compliant with a desired encircled flux (“EF”). The unit includes a light source to generate an optical light signal and a conventional multimode optical fiber coupled to receive the optical light signal from the light source at a first end. A modal conditioner is arranged to condition the optical light signal propagating along different modes of the conventional multimode fiber. A first bend-insensitive (BI) multimode optical fiber has an input end, the input end of the first BI multimode optical fiber being coupled at a second end of the conventional multimode optical fiber to receive the conditioned optical light signal from the conventional multimode fiber. The output from the first BI multimode optical fiber outputs an optical signal having the desired EF.

A high-sensitivity high-temperature sensor based on dislocation welding of suspended optical fiber is provided and includes a broadband light source, an optical fiber circulator, a sensing head and a spectrometer. The optical fiber circulator is connected to the broadband light source, the sensing head and the spectrometer individually, the sensing head includes a first single-mode optical fiber, a multi-mode optical fiber, a suspended core optical fiber and a second single-mode optical fiber which are connected in sequence. The high-sensitivity high-temperature sensor has the following advantages: simple to manufacture, no need for expensive special equipment; small sizes, compact structure, easy to use; full optical fiber structure, which can measure high temperatures up to 1000 degrees; no need for adhesive, good sensor stability; double cavities in parallel can generate vernier effects with high sensitivity.

A multimode optical fiber having a core region. The core region includes silica, has an outer radius r.sub.1, and has a maximum relative refractive index of about 1.5% or less. Additionally, the multimode optical fiber is configured to have an effective bandwidth of about 4.7 GHz-Km or greater for an excited portion of the core region that has a diameter greater than 50 microns, the effective bandwidth being at a wavelength that is within a range of between about 800 and about 1370 nm.

The present disclosure relates to semiconductor structures and, more particularly, to multi-mode optical waveguide structures with isolated absorbers and methods of manufacture. The structure includes: a waveguide structure including tapered segments; and at least one isolated waveguide absorber adjacent to the waveguide structure along its length.

The invention relates to a waveguide and a polarisation splitter based on said waveguide, in which a rotation of an angle greater than zero is applied to a plurality of sections of a core material and a plurality of sections of a covering material, thereby achieving an independent control of the refractive indices of a zero-order transverse electric mode and a zero-order transverse magnetic mode. This document also describes a manufacturing method of said waveguide which allows the birefringence of the light that passes through the waveguide.

An MCF or the like according to the present disclosure ensures sufficient manufacturing tolerance, is excellent in mass productivity, and is also capable of suppressing degradation of splice loss. The MCF includes four cores that extend along a central axis, and a common cladding. On a cross-section, the common cladding has a circular outer periphery, the four cores are arranged at positions to be line symmetric with respect to a straight line that intersects with a central axis and that intersects with none of the four cores, and a core arrangement defined by the four cores has rotational symmetry once with central axis being a center of rotation.

An apparatus (1) for guiding light and a method for producing a photonic lantern (2) are described. The apparatus (1) for guiding light from an input side (5) to an output side (6), comprises an input waveguide (3) at the input side (5) formed by at least two multi-mode fibres (7), an output waveguide (4) at the output side (7) formed by a single multi-mode fibre (5) and a photonic lantern (2) optically connecting the at least two multi-mode fibres (7) of the input waveguide to the single multi-mode fibre (8) of the output waveguide. The photonic lantern (2) is being designed such that, light transmitted by light guiding cores (9) of the at least two multi-mode fibres (7) of the input waveguide (3) is coupled into a light guiding core (10) of the single multi-mode fibre (8) of the output waveguide (4) and propagates through the light guiding core (10) of the single multi-mode fibre (8) of the output waveguide (4) and that claddings (11) surrounding the light guiding cores (9) of the at least two multi-mode fibres (7) of the input waveguide (3) are tapered down until they do at least almost not confine light.

An object of the present invention is to provide a simple method capable of reducing MDL after construction of a transmission path.

An optical connector 301 is an optical connector including a multimode optical fiber 11, in which a core 20 of the multimode optical fiber 11 includes a plurality of cavities 25 along a central axis. The optical connector 301 further includes a ferrule 12 surrounding the multimode optical fiber 11 and a connector plug 13 serving as a connection with another optical connector. The shape of the optical connector 13 is a shape of a generally used SC connector, FC connector, MT connector, or the like.

A test apparatus has at least one optical source, a high-speed photodetector, a microcontroller or processor, and electrical circuitry to power and drive the optical source, high-speed photodetector, and microcontroller or processor. The apparatus measures the frequency response and optical path length of a multimode optical fiber under test, utilizes a reference VCSEL spatial spectral launch condition and modal-chromatic dispersion interaction data to estimate the channels total modal-chromatic bandwidth of the fiber under test, and computes and presents the estimated maximum data rate the fiber under test can support.

An optical fiber comprising: (a) a core having an outer radius r.sub.1; (b) a cladding having an outer radius r.sub.4<32.5 microns; (c) a primary coating surrounding the cladding having an outer radius r.sub.5, a thickness t.sub.P>8 microns, in situ modulus E.sub.P≤0.35 MPa and a spring constant χ.sub.P<2.0 MPa, where χ.sub.P=2E.sub.P r.sub.4/t.sub.P; and (d) a secondary coating surrounding said primary coating, the secondary coating having an outer radius r.sub.6 and a thickness t.sub.S=r.sub.6−r.sub.5, and in situ modulus E.sub.S of 1200 MPa or greater; t.sub.S>8 microns, r.sub.6≤56 microns. The fiber has a mode field diameter MFD greater than 8.2 microns at 1310 nm; a fiber cutoff wavelength of less than 1310 nm; and a bend loss at a wavelength of 1550 nm, when wrapped around a mandrel having a diameter of 10 mm, of less than 1.0 dB/turn.