Fitel USA Corporation

Other

Lucent Technologies Inc.

Fitel Ush Corp.

Siu-Ping Hong

David Kalish

Thomas John Miller

Zhi Zhou

Jason W Shiroishi

Xiaoyuan Dong

James A Hudson

James William Fleming

Ian A White

Steven Alan Jacobs

Harry Douglas Garner, Jr

Albert John Ritger

Paul Francis Glodis

Alan H McCurdy

Haiying Huang

Urmi Ray

Nirupama Kenkare

Don H Smith

Jeffrey Jonathan Evans

Shunhe Xiong

Ronald Lamar Adams

Gene Kent Weeks

Stephen Mast

John F Ryan, Iii

John Popwell

Trudy Murrell Thiele

Methods for modifying preform core ovality during and subsequent to the formation of an optical fiber preform. After MCVD deposition forms the core rod, but prior to overcladding of the core rod, the code rod may be etched to change its ovality. In order to etch the core rod, the core rod may be mounted to lathe, rotated by at least two rotors, and subjected to a heat source. Additionally, one of the at least two rotors may be phase-shifted from another one of the at least two rotors after the core rod is mounted on the lathe.

Methods for modifying ovality of optical fiber preforms

An expeditious method for introducing geometric perturbations into lightguide during fabrication offers a perturbation stream of amplitude and periodicity&#x2014;constant or varying&#x2014;to satisfy a variety of needs.

Optical fiber fabrication and product

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.

Methods and apparatuses for correcting mechanical twist in optical fiber

Systems and methods are disclosed for an automatic and continuous supply of coating material to a coating applicator in optical fiber fabrication. The present invention switches from one coating reservoir to another by way of a transitional period in which both coating reservoirs are supplying coating material to the coating applicator. For example, while an in-use reservoir is supplying the coating material to the coating applicator, a standby reservoir is being filled, settled to off gas air bubbles and then slowly pressurized. A sized orifice is used to slowly bleed off pressure from the in-use reservoir at a rate that does not allow the pressure in the in-use reservoir from falling out of a desired pressure range. When the in-use reservoir is substantially emptied of coating material and the pressures in both reservoirs are substantially equalized, then both reservoirs simultaneously supply coating material to the coating applicator for a period of time before switching completely over to the standby reservoir.

Systems and methods for automatic and continuous coating supply during optical fiber production

Methods and apparatuses estimate and control optical fiber primary coating diameter for wet-on-wet optical fiber manufacturing. The primary coating diameter for a particular length of optical fiber is calculated based upon a measurement of the weight of primary and/or secondary coating material consumed during optical fiber manufacturing. Control of the primary coating diameter is effected by a coating controller which can increase or decrease the primary coating diameter through control of glass temperature, coating viscosity and/or other parameters during wet-on-wet fiber manufacture.

Methods and apparatuses for controlling optical fiber primary coating diameter

Defects in optical fibers are detected during manufacturing by using three bandpass filters to separate signals from a scattered light signal produced by a light source in a fiber measurement system. The separated signals include a clad diameter signal, a regular airline signal and a core airline signal. The regular airline signal is compared with the clad diameter signal to produce a normalized regular airline signal, and the core airline signal is compared with the clad diameter signal to produce a normalized core airline signal. The normalized regular airline signal and normalized core airline signal are monitored to determine if they increase, which indicates the presence of a defect in the optical fiber.

Method and apparatus for detecting airlines in optical fibers

Embodiments of the invention include a method and apparatus for making optical fiber preforms and optical fiber. The method includes the steps of positioning an overclad tube around a preform core rod, heating the overclad tube along the length thereof in the presence of a pressure gradient to collapse onto the preform core to form the overclad optical fiber preform, and adjusting the radial size of a heated portion of the preform core rod and/or the overclad tube to actively match the radial dimensions of the preform core rod along the length thereof with corresponding portions of the overclad tube. The active matching reduces variations in the physical dimensions of the preform core rod and/or the overclad tube, which improves transmission and other performance characteristics of fiber drawn from the created preform, e.g., by maintaining a relatively constant D/d ratio of the preform.

Method and apparatus for making improved optical fiber preforms and optical fiber therefrom

Embodiments of the invention include a method and apparatus for making a multiple overclad optical fiber preform. The method includes positioning a first overclad tube around a preform core rod, positioning at least one second overclad tube around the first overclad tube, and collectively heating the preform core and the overclad tubes under pressure to collapse the overclad tubes onto the preform core rod thus producing a multiple overclad optical fiber preform. The apparatus includes a preform core rod, a first overclad tube surrounding the preform core rod, and at least one second overclad tube surrounding the first overclad tube. A quartz disc with or without one or more quartz spacers is used for supporting the preform core rod and the first overclad tube within the additional overclad tubes.

Collapsing a multitube assembly and subsequent optical fiber drawing in the same furnace

Glass preforms are cleaned by contacting each preform (,) with supercritical carbon dioxide which dissolves residual index-matching oil on the preform. The liquefied carbon dioxide is then converted to gaseous carbon dioxide which conveniently separates the index-matching oil so that it can be recovered and reused. The gaseous carbon dioxide is likewise recycled for use in cleaning other preforms, and so there is substantially no waste.

Optical fiber preform cleaning method

Growing community of inventors

Alpharetta, GA, United States of America

Siu-Ping Hong