Lucent Technologies Inc.

Baker Hughes Corporation

Onetta, Inc.

Baker Hughes, a Ge Compnay, LLC

At&t Bell Laboratories

Intuitive Surgical Operations, Inc.

Inplane Photonics, Inc.

Unopsys, LLC

Alcatel Lucent

Alcatel-lucent USA Inc.

Lgs Innovations LLC

Baker Hughes Holdings LLC

Paul Francis Wysocki

Rolando Patricio Espindola

Christopher H Lambert

Douglas P Holcomb

David John DiGiovanni

Sergey V Frolov

Thomas Andrew Strasser

Brooks A Childers

Joseph Shmulovich

Carl W Stoesz

Neal S Bergano

Roger Glen Duncan

Andrew John Stentz

Stephen Tod Kreger

Juan P Franco

William S Wong

Mitchell Steven Wlodawski

Maxim A Bolshtyansky

Vincent J Mazurczyk

Mark Earl Froggatt

Jefferson L Wagener

Allan James Bruce

Paul S Westbrook

Kenneth L Walker

Thomas Huntington Wood

Ian Bradford Mitchell

James W Sulhoff

William Albert Johnston

Atul Kumar Srivastava

James Patrick Koonmen

Yan Sun

Jon W Engelberth

Daniel Boyd Cooper

Justin Boyd Judkins

Tek-Ming Shen

Ashwin Chandran

Gloria R Jacobovitz-Veselka

John J DeMarco

Ajit Balagopal

Chia-Chi Wang

Stephan Wielandy

Kim Willard Womack

Matthew Thomas Raum

Isaac Ryazansky

Paul Bollond

Jeff T Lacroix

Alan Heaney

Ken Walker

Namkyoo Park

Kenneth Walker

An embodiment of a system for performing measurements in a downhole environment includes an optical interrogation assembly configured to emit a pulsed optical signal, the pulsed optical signal including a selected wavelength, and an optical fiber configured to be disposed in a borehole in an earth formation and configured to receive the pulsed optical signal, the optical fiber having at least one measurement location disposed therein and configured to at least partially reflect the pulsed optical signal. The optical fiber has a core and a cladding, at least a portion of the core made from at least substantially pure silica, and the optical fiber has a refractive index profile configured to have a zero dispersion wavelength that is greater than the selected wavelength.

Dispersion-shifted optical fibers for downhole sensing

A sensing apparatus includes a sheath, a central member disposed in the sheath, at least one optical fiber disposed with the central member, and a film adhesive disposed between the central member and the sheath, the film adhesive provided in one or more sheets or strips and disposed in one or more layers between the central member and the sheath, and the film adhesive attached to the sheath.

Distributed sensing system employing a film adhesive

An embodiment of a method of manufacturing a fiber optic cable includes selecting a cable support structure configured to support an optical fiber sensor, adhering the optical fiber sensor to the cable support structure by applying a temporary adhesive, and installing a protective layer around the cable support structure and the temporarily adhered optical fiber sensor. The method further includes removing a bond between the optical fiber sensor and the temporary adhesive, wherein removing the bond includes injecting a debonding material into a space formed between the cable support structure and the protective layer, and injecting a permanent adhesive into the space, the permanent adhesive configured to immobilize the optical fiber sensor relative to the protective layer and allow strain to be transferred from the protective layer to the optical fiber sensor.

Strain locked fiber optic cable and methods of manufacture

A temperature sensing arrangement includes a member having a first coefficient of thermal expansion, and an optical fiber having a second coefficient of thermal expansion. The optical fiber is strain transmissively mounted to the member. And the first coefficient of thermal expansion is greater than the second coefficient of thermal expansion such that strain measurable in the optical fiber is correlatable to temperature changes in the member.

Temperature sensing arrangement, method of making the same and method of sensing temperature

A method of measuring acoustic energy impinging upon a cable includes, interrogating at least one optical fiber of the cable with electromagnetic energy, the at least one optical fiber is nonconcentrically surrounded by and strain locked to a sheath of the cable, monitoring electromagnetic energy returned in the at least one optical fiber, and determining acoustic energy impinging on the cable.

Method of measuring acoustic energy impinging upon a cable

An apparatus for estimating a parameter includes: an optical fiber sensor including at least one optical fiber configured to be disposed in a downhole location and including at least one sensing location configured to generate measurement signals; at least one light source configured to transmit a measurement signal having a wavelength to interrogate a sensing location and cause the sensing location to return a reflected measurement signal indicative of a measured parameter, and configured to transmit a reference signal and cause a reflected reference signal to be returned from a location associated with the sensing location, the reflected reference signal having a known relationship to hydrogen concentration; and a processor configured to receive the reflected measurement signal and the reflected reference signal, estimate the hydrogen concentration based on the reflected reference signal, and calibrate the first reflected signal based on the estimated hydrogen concentration.

Loss compensation for distributed sensing in downhole environments

A fiber optic cable arrangement includes a core, a sheath surrounding the core and being strain locked to the core, and at least one optical fiber positioned within the sheath being strain locked to the core.

Fiber optic cable arrangement

A twisted, multicore fiber communicates light input to each core to an output. The twisting mitigates relative time delays of the input light traveling through each of the cores in the multicore fiber to the output caused by bending of that multicore fiber. An example application is in an optical network that includes an optical input terminal and an optical sensor connected by a twisted multicore connecting fiber. One example of twisted multicore optical fiber is helically-wrapped, multicore fiber.

Co-registration of cores in multicore optical fiber sensing systems

An optical cable includes an outer tubing. At least one optical fiber disposed within the outer tubing. A stiffening member configured to bend with bending of the outer tubing; wherein the stiffening member shifts a neutral plane of the cable away from the at least one optical fiber. Also included is a method of increasing a bending sensitivity in an optical cable.

Optical cable, downhole system having optical cable, and method thereof

A method and structure for terminating an optical fiber are disclosed that provide an optical fiber termination structure with a small volume and very low return loss, even when the termination is in close proximity to reflective surfaces. In one example embodiment, the optical fiber termination reduces reflections into the one or more cores to a return loss of &#x2212;70 dB or less regardless of the presence of surfaces proximate the optical fiber termination. At the same time, a length of the optical fiber termination is less than 5 mm and a largest transverse dimension of the optical fiber termination is less than 325 um. The optical fiber termination is useful in fiber sensing applications in general and is particularly effective for terminating a multi-core fiber used in a distributed shape sensing application.

Reducing reflection at termination of optical fiber in a small volume

Systems and methods for monitoring signals in an optical fiber amplifier system are provided. The optical amplifier system includes a tapered fiber bundle which couples optical energy into the cladding of an optical amplifier. A signal passing through the optical amplifier is amplified. To monitor the amplified signal, a single fiber of a tapered fiber bundle may be used as a monitor fiber. Alternatively, a monitor or coupler may be integrated into the tapered fiber bundle during manufacturing. The systems and methods disclosed allow for monitoring the amplified signal without increasing the length of the amplified signal's path, thus minimizing the introduction of additional non-linearities.

Tapered fiber bundle apparatus with monitoring capability

An optical amplifier comprises at least two gain regions, an intermediate region situated between the gain regions, and a transition region situated between the intermediate region and each gain region. The aforesaid regions have claddings that collectively form a path for pump radiation propagating from at least one of the gain regions to the other gain region, and cores that collectively form a path for signal radiation propagating from at least one of the gain regions to the other gain region. The cores in the gain regions support multiple propagating optical modes, including at least one signal mode and at least one non-signal mode. The intermediate region, however, supports fewer propagating core modes than are supported by the gain regions. The transition regions are conformed such that when radiation in propagating non-signal core modes passes from the gain regions into the intermediate region, it is at least partly coupled into cladding modes of the intermediate region.

Cladding-pumped optical amplifier having reduced susceptibility to spurious lasing

A universal inline functional module for operation with nonzero average gain G&#x2260;0dB over a bandwidth is provided. The module includes at least one optical functional element producing loss over the bandwidth and at least one rare-earth doped fiber segment. The module produces a flat gain spectrum to within a specified tolerance when made to operate at an average gain of 0 dB over the bandwidth.

Article comprising a multichannel optical amplified transmission system with functional upgrade capabilities and universal modules

A method and apparatus for improved efficiency in optical fiber lasers. The system increases the efficiency of cladding pumped optical fiber amplifiers through a seeding technique which includes pumping an erbium/ytterbium doped fiber amplifier with pump energy, directing an optical signal through the erbium/ytterbium doped fiber amplifier, and seeding the optical signal with seed energy. The seed energy may have a higher energy level than the optical signal and a lower energy level than the pump energy, and the seed energy may be initially amplified in the amplifier and subsequently attenuated while amplifying the optical signal in the amplifier.

Optical fiber laser having improved efficiency

A method for increasing the number of channels amplified by an optical amplifier arrangement is provided. The optical amplifier arrangement includes at least one optical amplifier stage amplifying a first number of channels at a given average gain level. The method begins by selecting a second number of channels to be amplified by the optical amplifier arrangement. At least one additional optical amplifier stage is serially coupled to an input or output of the at least one optical amplifier stage to form a multistage optical amplifier arrangement. The gain shape of the multistage optical amplifier is adjusted to maintain, at the given average gain level or greater, a prescribed degree of gain flatness over an operating bandwidth in which the second number of channels are located.

Article comprising a series expandable erbium-doped fiber amplifier (SE-EDFA)

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Flemington, NJ, United States of America

Paul Francis Wysocki