Abstract: Disclosed herein is a fiber optic system including at least one fiber optic cable assembly having a multimode optical fiber for communication of an optical data signal at an operating wavelength and a devices having a single-mode fiber stub with a mode field diameter within 20% of the mode field diameter of the fundamental mode of the multimode optical fiber at the operating wavelength. The single-mode fiber stub is secured to a ferrule, and a center of a core of the single-mode fiber stub is within 0.5 ?m of a center of the ferrule. An end of the single-mode fiber stub that extends to or beyond the back end of the ferrule and forms an optical connection with the multimode optical fiber where the center of the single-mode fiber stub is within 2 ?m of a center of the multimode optical fiber.

Abstract: An apparatus comprises a fiber input, the fiber input comprising a plurality of input fiber cores receiving a plurality of input optical signals. The apparatus also comprises an optical signal manipulation device that is one of a fiber mode shuffler, a fiber coupler, a power splitter, or a 90-degree optical hybrid. The optical signal manipulation device comprises an input aperture held in spaced relation to the fiber input, an output aperture, and a plurality of metasurfaces that manipulate phase profiles of the plurality optical signals to generate a plurality of output optical signals having a different spatial arrangement than the input optical signal. A fiber output is held in spaced relation to the output aperture such that fiber cores of the fiber output receive the plurality of output optical signals.

Abstract: A few mode optical fiber that includes a core and a cladding surrounding the core, the cladding comprising at least one stress member. The core and the cladding support the propagation and transmission of at least LP01, LP11a, and LP11b modes at one or more wavelengths. Furthermore, the LP01, LP11a, and LP11b modes each have a birefringence of about 5.7×10?6 or less at 1310 nm. And an effective index difference between the LP11a and LP11b modes is about 3.0×10?5 or greater.

Abstract: A method of categorizing single mode optical fibers, the method including determining one or more fiber properties of an optical fiber, the optical fiber being a single mode optical fiber at an operating wavelength of about 1310 nm. The method further including calculating a peak bandwidth wavelength of the optical fiber based on the one or more fiber properties, comparing the calculated peak bandwidth wavelength with a target peak bandwidth wavelength and based on the comparison, determining if the optical fiber meets a target modal bandwidth.

Abstract: The optical fibers disclosed have single mode and few mode optical transmission for VCSEL-based optical fiber transmission systems. The optical fibers have a cable cutoff wavelength ?C of equal to or below 1260 nm thereby defining single mode operation at a wavelength in a first wavelength range greater than 1260 nm and few-mode operation at a wavelength in a second wavelength range from 970 nm and 1070 nm. The mode-field diameter is in the range from 9.3 microns to 10.9 microns at 1550 nm. The optical fibers have an overfilled bandwidth OFL BW of 1 GHz.km to 3 GHz.km at the at least one wavelength in the second wavelength range. VCSEL based optical transmission systems and methods are disclosed that utilize both single core and multicore versions of the optical fiber.

Abstract: A method of categorizing a group of multimode optical fibers, the method including comparing an effective modal bandwidth of a first multimode optical fiber with a first threshold, the first multimode optical fiber being in a group of multimode optical fibers meeting a first OM-standard and the first threshold being an effective modal bandwidth of the first multimode optical fiber. The method further including categorizing the first multimode optical fiber as meeting OM functional requirements of a second OM-standard if the effective modal bandwidth of the first multimode optical fiber is equal to or above the first threshold, wherein the second OM-standard is higher than the first OM-standard.

Abstract: An optical system, comprising: (i) multiple input optical fibers; (ii) an optical mode multiplexer/demultiplexer coupled to said input optical fibers with, said optical mode multiplexer/demultiplexer comprising a plurality of metamaterial structures having length and forming at least one stage of metamaterials, the at least one stage of metamaterials is being situated on a surface of the optical mode multiplexer/demultiplexer facing the input optical fibers, and the at least one stage of metamaterials is oriented at angles between 60 and 120 degrees relative to the axis of the input fibers; and the metasurfaces are structured to receive a first optical signal having a first mode from at least one of said multiple input optical fibers and convert the first mode to a different mode.

Abstract: Systems, devices, and techniques for performing wavelength division multiplexing or demultiplexing using one or more metamaterials in an optical communications systems are described. An optical device may be configured to shift one or more phase profiles of an optical signal using one or more stages of metamaterials to multiplex or demultiplex wavelengths of optical signals. The optical device may be an example of a stacked design with two or more stages of metamaterials stacked on top of one another. The optical device may be an example of a folded design that reflects optical signals between different stages of metamaterials.

Abstract: Systems, devices, and techniques for performing wavelength division multiplexing or demultiplexing using one or more metamaterials in an optical communications systems are described. An optical device may be configured to shift one or more phase profiles of an optical signal using one or more stages of metamaterials to multiplex or demultiplex wavelengths of optical signals. The optical device may be an example of a stacked design with two or more stages of metamaterials stacked on top of one another. The optical device may be an example of a folded design that reflects optical signals between different stages of metamaterials.

Abstract: A method including transmitting an intensity-modulated light through a mode conditioner to generate a mode-conditioned intensity-modulated light in one or a plurality of launch conditions and transmitting the mode-conditioned intensity-modulated light through a multimode optical fiber under test (FUT) to excite a plurality of modes of the FUT. The method further includes converting the mode-conditioned intensity-modulated light transmitted through the FUT into an electrical signal, measuring, based on the electrical signal, a complex transfer function CTF(f) of the FUT, and obtaining an output pulse based on the measured complex transfer function CTF(f) from one or a plurality of launch conditions and an assumed input pulse using the equation: Pout (t)=?1(CTF(f)*(Pin(t))). Wherein, Pout (t) is the output pulse, ?1(CTF(f)*(Pin(t))) is the inverse Fourier transform of the function CTF(f)*(Pin (t)), and (Pin(t)) is the Fourier transform of the assumed input pulse.

Abstract: The optical fibers disclosed have single mode and few mode optical transmission for VCSEL-based optical fiber transmission systems. The optical fibers have a cable cutoff wavelength ?C of equal to or below 1260 nm thereby defining single mode operation at wavelengths greater than 1260 nm and few-mode operation at wavelengths in a wavelength range from 800 nm and 1100 nm. The mode-field diameter is in the range from 8.0 microns to 10.1 microns at 1310 nm. The optical fibers have an overfilled bandwidth OFL BW of at least 1 GHz·km at at least one wavelength in the wavelength range. The optical fibers have a single-step or two-step core and can have a trench refractive index profile. VCSEL based optical transmission systems and methods are disclosed that utilize both single core and multicore versions of the optical fiber.

Abstract: A multimode optical fiber having a core region. The core region includes silica, has an outer radius r1, 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.

Abstract: A optical fiber comprising a central core region having an outer radius r1 of 3 ?m to 7 ?m, and a maximum refractive index ?1 of 0.25% to 0.5% and an alpha (a) profile of 1 to 20; a cladding region comprising (i) a first inner cladding region surrounding the core, having a refractive index ?2 of ?0.25% to 0.05% and a radius r2 of 6 ?m to 15 ?m, (ii) a second inner cladding region, surrounding the first inner cladding region, having a refractive index ?3 of ?0.1% to 0.2% and a radius r3 of 7 ?m to 15 ?m, and (iii) an outer cladding region, surrounding the second inner cladding region, having a refractive index ?4 between ?0.05% to 0.1%; wherein the optical fiber exhibits a cable cutoff of less than 1260 nm, a mode field diameter at 1310 nm of greater than 8.2 microns.

Abstract: A multimode optical fiber having a core region. The core region includes silica, has an outer radius r1, 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.

Abstract: The present disclosure is directed to systems and methods for calculating a modal time delay and a modal bandwidth. For example, a method may include: transmitting an intensity-modulated light through a mode conditioner to generate a mode-conditioned intensity-modulated light; transmitting the mode-conditioned intensity-modulated light through an optical fiber under test (FUT) to excite a plurality of modes of the optical FUT; converting the mode-conditioned intensity-modulated light transmitted through the optical FUT into an electrical signal; measuring, based on the electrical signal, a transfer function or a complex transfer function of the optical FUT based on at least on one pair of the plurality of modes; calculating a modal delay time of the optical FUT based on the transfer function or the complex transfer function; and calculating a modal bandwidth of the optical FUT based on the modal delay time, the modal bandwidth being calculated for any given launch conditions of the plurality of modes.

Abstract: Methods of forming a bandwidth-tuned optical fiber for short-length data transmission systems include establishing a relationship between a change ?? in a modal delay ?, a change ?T in a draw tension T and a change ?? in a BM wavelength ? of light in a BM wavelength range from 840 nm and 1100 nm for a test optical fiber drawn from a preform and that supports BM operation at the BM wavelength. The methods also include drawing from either the preform or a closely related preform the bandwidth-tuned optical fiber by setting the draw tension based on the established relationships of the aforementioned parameters so that the bandwidth-tuned optical fiber has a target bandwidth greater than 2 GHz·km at a target wavelength within the BM wavelength range.

Abstract: The optical fibers disclosed have single mode and few mode optical transmission for VCSEL-based optical fiber transmission systems. The optical fibers have a cable cutoff wavelength ?d C of equal to or below 1260 nm thereby defining single mode operation at wavelengths greater than 1260 nm and few-mode operation at wavelengths in a wavelength range from 800 nm and 1100 nm. The mode-field diameter is in the range from 8.0 microns to 10.1 microns at 1310 nm. The optical fibers have an overfilled bandwidth OFL BW of at least 1GHz·km at at least one wavelength in the wavelength range. The optical fibers have a single-step or two-step core and can have a trench refractive index profile. VCSEL based optical transmission systems and methods are disclosed that utilize both single core and multicore versions of the optical fiber.

Abstract: The present disclosure is directed to systems and methods for calculating a modal time delay and a modal bandwidth. For example, a method may include: transmitting an intensity-modulated light through a mode conditioner to generate a mode-conditioned intensity-modulated light; transmitting the mode-conditioned intensity-modulated light through an optical fiber under test (FUT) to excite a plurality of modes of the optical FUT; converting the mode-conditioned intensity-modulated light transmitted through the optical FUT into an electrical signal; measuring, based on the electrical signal, a transfer function or a complex transfer function of the optical FUT based on at least on one pair of the plurality of modes; calculating a modal delay time of the optical FUT based on the transfer function or the complex transfer function; and calculating a modal bandwidth of the optical FUT based on the modal delay time, the modal bandwidth being calculated for any given launch conditions of the plurality of modes.

Abstract: A multimode optical fiber transmission system that employs an optical fiber with at least one modal-conditioning fiber is disclosed. The system includes a single-mode transmitter that generates modulated light having a wavelength between 800 nm and 1600 nm; an optical receiver configured to receive and detect the modulated light; a multimode optical fiber that defines an optical path between the single-mode transmitter and the optical receiver, the multimode optical fiber having a core with a diameter D40 and a refractive index profile configured to optimally transmit light at a nominal wavelength of 850 nm; and at least one modal-conditioning fiber operably disposed in the optical path to perform at least one of modal filtering and modal converting of the optical modulated light.

Abstract: A multimode optical fiber transmission system that employs an optical fiber with at least one modal-conditioning fiber is disclosed. The system includes a single-mode transmitter that generates modulated light having a wavelength between 800 nm and 1600 nm; an optical receiver configured to receive and detect the modulated light; a multimode optical fiber that defines an optical path between the single-mode transmitter and the optical receiver, the multimode optical fiber having a core with a diameter D40 and a refractive index profile configured to optimally transmit light at a nominal wavelength of 850 nm; and at least one modal-conditioning fiber operably disposed in the optical path to perform at least one of modal filtering and modal converting of the optical modulated light.