A high-bandwidth bend-insensitive multimode optical fiber includes a core and a cladding. A refractive index profile of the core has a parabola shape and a distribution index thereof is . The core has a radius of 23-27 m. A maximum relative refractive index difference of a central position of the core is 0.9%-1.2%. The core is a germanium-fluorine co-doped silicon dioxide glass layer. The central position of the core has a minimum amount of fluorine doped, and a mass percentage of fluorine content is C.sub.F,min. A mass percentage of fluorine content of the core changes with the radius according to a function. The cladding successively comprises an inner cladding, a trench cladding, and an outer cladding from inside to outside. The optical fiber reduces bandwidth-wavelength sensitivity while improving bandwidth performance; is compatible with existing OM3/OM4 multimode optical fibers, and support wavelength-division multiplexing technology in a wavelength range of 850-950 nm.

A method for determining a curvature and/or torsion of an optical waveguide of a fibre-optic sensor, comprising at least two Bragg gratings introduced into the optical waveguide and extending through a common cross-sectional plane, situated in a radial direction, through the optical waveguide, wherein the Bragg gratings are introduced in the core and/or on the boundary between the core and the cladding and/or in an inner edge region of the cladding within an evanescence region of the light, the method comprising: providing reference data of intensities of reflected light portions of light coupled into the optical waveguide, in particular depending on known reference deformations of the optical waveguide, measuring at least one light intensity of reflected light portions of light coupled into the optical waveguide, wherein the optical waveguide has a deformation to be determined, and determining the deformation by comparing the light intensity with the reference data.

The present application is directed in various illustrative embodiments to an optical waveguide, an optical waveguide system with such an optical waveguide, a light energy storage structure, light confining structures, a light energy storage system and an energy storage and/or conversion system with such an optical waveguide system. In an aspect, an optical waveguide is provided, comprising an optical fiber with a fiber core and an optical active cladding structure over at least a portion of the fiber core at a first end of the optical waveguide, wherein the optical active cladding structure comprises a Bragg mirror stacking having a high transmittance in a first wavelength region and a high reflectivity in a second wavelength region of wavelengths longer than wavelengths in the first wavelength region, and a wavelength conversion coating over the fiber core of the optical fiber. The wavelength conversion coating is configured to convert radiation with wavelengths in the first wavelength region into radiation with wavelengths in the second wavelength region and the Bragg mirror stacking is disposed over the wavelength conversion coating.

Disclosed herein are methods, apparatus, and systems for providing an optical beam delivery system, comprising an optical fiber including a first length of fiber comprising a first RIP formed to enable, at least in part, modification of one or more beam characteristics of an optical beam by a perturbation assembly arranged to modify the one or more beam characteristics, the perturbation assembly coupled to the first length of fiber or integral with the first length of fiber, or a combination thereof and a second length of fiber coupled to the first length of fiber and having a second RIP formed to preserve at least a portion of the one or more beam characteristics of the optical beam modified by the perturbation assembly within one or more first confinement regions. The optical beam delivery system may include an optical system coupled to the second length of fiber including one or more free-space optics configured to receive and transmit an optical beam comprising the modified one or more beam characteristics.

The invention relates to an optical waveguide with two or more light-guiding cores (1a-1e) extending continuously along the longitudinal extension of the optical waveguide, parallel to one another and spaced apart from one another, from one end of the optical waveguide to the other, and with a first cladding (2) enclosing the cores (1a-1e). It is an object of the invention to provide a multicore optical waveguide for high-power operation with reduced system complexity compared to the prior art. This object is achieved by the invention in that the cores (1a-1e) are arranged relative to one another and are spaced apart from one another in such a way that the propagation modes of the light propagating in the optical waveguide at a working wavelength couple to one another, the length of the optical waveguide being selected such that the light coupled into only a single one of the cores (1a-1e) at one end of the optical waveguide first spreads to the other cores (1a-1e) during propagation through the optical waveguide and, after passing through the optical waveguide, leaves the optical waveguide again at the other end from a single core (1a) with at least 60%, preferably at least 75%, of the total light power propagating in the optical waveguide. The invention also relates to a laser system with such an optical waveguide as an optical amplifier, and a method for guiding light in an optical waveguide.

An optical fiber manufacturing apparatus includes a rotating mechanism including a holding member that holds one side of an optical fiber and a rotating member that rotates the holding member, the optical fiber including a glass fiber portion and a coating layer covering the glass fiber portion; a guiding member secured at a distance from the rotating mechanism and configured to retain the other side of the optical fiber loosely fitted therein; and a heating mechanism configured to heat a part of the glass fiber portion exposed and extending out of the coating layer, the part being interposed between the holding member and the guiding member. By rotating the rotating member counterclockwise by a given angle, the glass fiber portion is drawn from the guiding member and bent with a predetermined curvature while being heated.

A monolithic photonic integrated circuit includes a platform, a monolithic laser formed in/on the platform, and an electro-optic polymer modulator monolithically built onto the platform and optically coupled to the monolithic laser. The polymer modulator is optically coupled to the monolithic laser by waveguides including electro-optic polymer waveguides. The electro-optic polymer modulator and the electro-optic polymer waveguides including an electro-optic polymer core and top and bottom electro-optic polymer cladding layers. The electro-optic polymer core having an electro-optic coefficient (r.sub.33) greater than 250 pm/v, and a Tg 150 C. to >200 C., and the top and bottom electro-optic polymer cladding layers having a Tg approximately the same as the Tg of the electro-optic polymer core.

An imaging sensor includes at least one fiber Bragg grating for filtering an image from a subject for wavelength bands, and an imaging device for converting an image transmitted through the fiber Bragg grating into a digital signal.

An optical fiber includes a core, a depressed inner cladding surrounding the core, and an outer cladding surrounding the inner cladding, where a refractive index profile of the core includes an power distribution in which an index is 3.5 or more and 6 or less, a relative refractive index difference .sup. of the inner cladding with respect to the adding is set such that an absolute value |.sup.| thereof is 0.01% or more and 0.045% or less, a radius r1 of the core and an outer circumference radius r2 of the inner cladding are set such that a ratio r1/r2 thereof is 0.2 or more and 0.6 or less, a cable cutoff wavelength .sub.cc of 22 m is 1260 nm or less, and a mode field diameter MFD at a wavelength of 1310 nm is 8.6 m or more and 9.5 m or less.

An optical dispersion compensator integrated with a silicon photonics system including a first phase-shifter coupled to a second phase-shifter in parallel on the silicon substrate characterized in an athermal condition. The dispersion compensator further includes a third phase-shifter on the silicon substrate to the first phase-shifter and the second phase-shifter through two 22 splitters to form an optical loop. A second entry port of a first 22 splitter is for coupling with an input fiber and a second exit port of a second 22 splitter is for coupling with an output fiber. The optical loop is characterized by a total phase delay tunable via each of the first phase-shifter, the second phase-shifter, and the third phase-shifter such that a normal dispersion (>0) at a certain wavelength in the input fiber is substantially compensated and independent of temperature.