Abstract: Methods and apparatuses negate a measured mechanical twist of an optical fiber by introducing a counteracting twist to bring the net mechanical twist closer to zero, which reduces the fiber's polarization mode dispersion (PMD). A spool of optical fiber having undesirable mechanical twist is mounted and fiber is drawn from the end of the spool to impart a specified counteracting mechanical twist. Additionally, the spool may be controllably rotated by a control system while optical fiber is drawn there from, allowing the system to generate a precise amount of counteracting mechanical twist in the fiber.

Abstract: A system and method is disclosed for manufacturing single mode optical fiber which incorporates a spin in the molten fiber during manufacturing. The introduction of spin minimizes a form of distortion called polarization mode dispersion (PMD) and varying the spin, i.e. changing its characteristics, is known to further reduce PMD. However, introducing spin on a molten fiber may result in also introducing twist on the fiber. Twist is a non-permanent rotational force on the cooled fiber which causes stress and is to be avoided. A spin function is disclosed that not only contains a high degree of variability for reducing PMD, but also ensures that mechanical twist on the fiber is minimized, thus reducing stress on the fiber. The spin function modulates either the amplitude, frequency, or both, at the beginning of a cycle to minimize twist on the fiber.

Abstract: Methods and apparatuses negate a measured mechanical twist of an optical fiber by introducing a counteracting twist to bring the net mechanical twist closer to zero, which reduces the fiber's polarization mode dispersion (PMD). A spool of optical fiber having undesirable mechanical twist is mounted and fiber is drawn from the end of the spool to impart a specified counteracting mechanical twist. Additionally, the spool may be controllably rotated by a control system while optical fiber is drawn there from, allowing the system to generate a precise amount of counteracting mechanical twist in the fiber.

Abstract: Methods and apparatuses introduce mechanical twist to an optical fiber having relatively large polarization mode dispersion (PMD), such as unspun fiber or fiber spun with constant spatial frequency, which mechanical twist reduces the fiber's PMD. A spool of optical fiber having relatively large PMD is mounted and fiber is pulled from the end of the spool to impart a specified mechanical twist. Additionally, the spool may be controllably rotated by a control system while optical fiber is pulled therefrom, allowing the system to generate a precise amount of mechanical twist to the fiber. Also, it is possible to measure the amount of mechanical twist in an optical fiber and the amount of mechanical twist in an optical fiber as a function of fiber length.

Abstract: Systems and methods are disclosed for measuring Polarization Mode Dispersion (PMD) of single-mode optical fiber. The method allows for a faster and easier method of accurately measuring intrinsic ultra low PMD optical fiber in a low mode coupling state. The method involves the introduction of a plurality of localized external perturbations on the optical fiber, after which the optical fiber is allowed to reach a steady state, and then measurement of the differential group delay occurs using standard measurement techniques. The plurality of localized external perturbations is altered followed by another measurement of the differential group delay. After obtaining a sufficient number of measurements to provide a Maxwellian distribution, the Polarization Mode Dispersion value can be calculated as the average of the distribution.

Abstract: Systems and methods are disclosed for measuring Polarization Mode Dispersion (PMD) of single-mode optical fiber. The method allows for a faster and easier method of accurately measuring intrinsic ultra low PMD optical fiber in a low mode coupling state. The method involves the introduction of a plurality of localized external perturbations on the optical fiber, after which the optical fiber is allowed to reach a steady state, and then measurement of the differential group delay occurs using standard measurement techniques. The plurality of localized external perturbations is altered followed by another measurement of the differential group delay. After obtaining a sufficient number of measurements to provide a Maxwellian distribution, the Polarization Mode Dispersion value can be calculated as the average of the distribution.

Abstract: A system and method is disclosed for manufacturing single mode optical fiber which incorporates a spin in the molten fiber during manufacturing. The introduction of spin minimizes a form of distortion called polarization mode dispersion (PMD) and varying the spin, i.e. changing its characteristics, is known to further reduce PMD. However, introducing spin on a molten fiber may result in also introducing twist on the fiber. Twist is a non-permanent rotational force on the cooled fiber which causes stress and is to be avoided. A spin function is disclosed that not only contains a high degree of variability for reducing PMD, but also ensures that mechanical twist on the fiber is minimized, thus reducing stress on the fiber. The spin function modulates either the amplitude, frequency, or both, at the beginning of a cycle to minimize twist on the fiber.

Abstract: A communication jack has a first pair and a second pair of contact wires defining corresponding signal paths in the jack. Parallel, co-planar free end portions of the wires are formed to connect electrically with a mating connector that introduces offending crosstalk to the signal paths. First free end portions of the first pair of contact wires are supported adjacent one another, and second free portions of the second pair are supported adjacent corresponding ones of the first free end portions. Intermediate sections of the first pair of contact wires diverge vertically and traverse one another to align adjacent to corresponding intermediate sections of the second pair of wires, to produce sufficient inductive compensation coupling to counter the offending crosstalk from the plug. Capacitive compensation coupling may be obtained for the contact wires via one or more printed wiring boards supported on or in the jack housing.