Ofs Fitel, LLC

Fitel USA Corporation

Furukawa Electric North America, Inc.

Furukawn Electric North America, Inc.

Jinkee Kim

Kelvin B Bradley

Gregory Alen Sandels

Man Fei Yan

David Kalish

George Edward Oulundsen, Iii

Robert Lingle, Jr

Durgesh Vaidya

Xinli Jiang

Yi Sun

Yifei Qian

James William Fleming

Willard C White

Harry Douglas Garner, Jr

Robert L Lingle

Sean L Jones

Zhi Zhou

Roman Shubochkin

Yu Lu

Alan H McCurdy

Donald Jablonowski

Kasyapa Balemarthy

George Oulundsen

George E Oulundsen

Durgesh Shivram Vaidya

Described is a technique for the design and manufacture of MMFs. Designs are implemented so as to limit the maximum variation in z(r, &#x3bb;) with respect to wavelength, where z(r, &#x3bb;) is the dielectric constant weighted by the square of the wavelength. MMFs for use in CWDM applications are specifically described.

Manufacture of multi-mode optical fibers

Structures and techniques are described relating to the alignment of multicore fibers within a multifiber connector. These structures and techniques include: multicore fibers having a number of different shapes, including, for example, circular, elliptical, D-shaped, double D-shaped, and polygonal; multifiber ferrules, having a plurality of fiber guide holes therein of various shapes; alignment fixtures for aligning multicore fibers within multifiber ferrules; and various multicore fiber alignment techniques.

Multifiber connectorization techniques for multicore optical fiber cables

An optical fiber ferrule has a plurality of guide holes therein for guiding a respective plurality of flat-sided fibers at an end of a multifiber optical fiber cable. The fibers' flat sides identify a particular rotational orientation of the fiber. Rotational alignment is achieved by urging the fibers' flat sides against a corresponding reference surface within the ferrule or within an alignment fixture. Also described is a fiber array block having a plurality of V-shaped grooves extending across an outer surface and terminating at an endface. The V-shaped grooves are shaped to guide a respective plurality of flat-sided fibers. A lid is installable across the plurality of V-shaped grooves, over fibers that have been loaded therein.

Connectorization techniques for polarization-maintaining and multicore optical fiber cables

Optical fiber designs are depicted with a core having an alpha profile inner portion and a steep vertical step between the core and a cladding with no shoulder, referred to herein as a truncated core. A further aspect of this invention can include a trench between the truncated core and cladding. In this embodiment, the core performs as not only as the primary light guiding structure, but now also functions essentially the same as that of a trench structure. Thus, what was formally a trench can now be much less negative or even positive. Another embodiment of the present invention includes an optical fiber having a truncated core with the addition of a ledge or shoulder between the core and vertical step, followed directly by a cladding.

Optical fibers with truncated cores

Connectors for use with polarization-maintaining and multicore optical fiber cables

Multifiber connectors for multicore optical fiber cables

An optical fiber cable connector includes a ferrule with a guide hole that is shaped to closely receive a multicore fiber having a flat side indicative of the rotational orientation of the cores of the multicore fiber. The ferrule includes a flat surface at one side of the guide hole, corresponding in position to the flat side of the multicore fiber. Installing the multicore fiber into the guide hole with its flat side abutting the flat surface along the side of the guide hole provides alignment of the cores with respect to an optical component to which the multicore fiber endface is to be connected.

Single-fiber connectors for optical fiber cables

Optical fiber refractive index profile designs having an alpha core profile and a negative index trench to control bend loss, are modified by truncating the edge of the alpha core profile and adding a ledge to the truncated core. The result is low bend loss and preservation of low differential mode delay and high bandwidth.

DMD performance in bend optimized multimode fiber

The specification describes multimode optical fibers with specific design parameters, i.e., controlled refractive index design ratios and dimensions, which render the optical fibers largely immune to moderately severe bends. The modal structure in the optical fibers is also largely unaffected by bending, thus leaving the optical fiber bandwidth essentially unimpaired. Bend performance results were established by DMD measurements of fibers wound on mandrels vs. measurements of fibers with no severe bends.

Bandwidth-maintaining multimode optical fibers

An improved optical fiber design has been found to exhibit a relatively low attenuation at the wavelength of 1385 nm (the 'water peak'), allowing for Raman amplification to be efficient and effective at wavelengths in the S-band range of 1460 to 1530 nm. An ultra-dry process is used to mate an inner core rod (core plus surrounding trench) with a cladding tube (ring region plus cladding layers) and provide a water peak loss on the order of 0.325 dB/km. The low water peak is combined with appropriate dispersion values and zero dispersion wavelength to form a fiber that supports transmission and Raman amplification in the S-, C- and L-bands of interest for optical transmission systems.

Optical fiber for improved performance in S-, C- and L-bands

A laser cleaving apparatus for use in terminating optical fiber cable ends has a laser beam source, the output of which is directed through a beam distorting member, which produces a beam having a chisel shape with a substantially flat side normal to the axis of a connector fiber containing ferrule and focuses it onto the fiber at a point adjacent the ferrule end face with the flat side also adjacent the end face. A single step polishing stage polishes the cleaved fiber end face to make it flat and flush with the ferrule end face.

Laser cleaving method and apparatus for optical fiber cables

The specification describes an improved optical fiber design in which the criteria for high performance in a Raman amplified optical system, such as moderate effective area, moderate dispersion, low dispersion slope, and selected zero dispersion wavelength, are simultaneously optimized. In preferred embodiments of the invention, the dispersion characteristics are deliberately made selectively dependent on the core radius. This allows manufacturing variability in the dispersion properties, introduced in the core-making process, to be mitigated during subsequent processing steps.

Method for the manufacture of optical fibers, improved optical fibers, and improved raman fiber amplifier communication systems

Method for the manufacture of optical fibers, improved optical fibers, and improved Raman fiber amplifier communication systems

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.

Growing community of inventors

Norcross, GA, United States of America

Jinkee Kim