Ii-vi Incorporated

Ii-vi Delaware, Inc.

Nortel Networks Corporation

Ian Peter McClean

Aravanan Gurusami

Nadhum Kadhum Zayer

Martin Richard Williams

Timothy K Zahnley

Scott R Dahl

Manish Sharma

Peter Gerard Wigley

Eric Timothy Green

Deepak Devicharan

Michael J Cahill

Mark H Garrett

Yajun Wang

Massimo Martinelli

Mark Filipowicz

Kevan Jones

Paul Johnson

Yongshi Gu

Yongjun Fu

Zhiqian Zhu

Stephen Fourte

An amplifier operable with an electric drive signal can amplify signal light having a signal wavelength. A laser diode has an active section with input and output facets. The facets are in optical communication with the signal light and are configured to pass the signal light through the laser diode. The active section is configured to generate pump light in response to injection of the electrical drive signal into the active section. The pump light has a pump wavelength different from the signal wavelength. A doped fiber doped with an active dopant is in optical communication with the signal light and is in optical communication with at least a portion of the pump light from the laser diode. The pump wavelength of the pump light is configured to interact with the active dopant of the fiber and thereby amplify the signal light.

Doped fiber amplifier having pass-through pump laser

A system for providing advanced characterization of an optical fiber span is based upon the use of a pair of optical time domain reflectometers (OTDRs), located at opposing end terminations of the span being characterized. Each OTDR performs standard reflectometry measurements and transmits the resulting OTDR trace to monitoring equipment in a typical manner. The pair of OTDR traces is thereafter combined in a particular manner ('stitched together') to create an OTDR trace of the entire fiber span (essentially doubling the operational range of prior art OTDR measurement capabilities). The transmit portion of one OTDR may be paired with the receive portion of the other OTDR, with time-of-light measurements (or signal loss measurements) used to determine optical path length and/or optical signal loss of the span. Using a multi-wavelength light source in the paired transmit/receive arrangement allows for a characterization of chromatic dispersion of the span.

Fiber span characterization utilizing paired optical time domain reflectometers

A dual output laser diode may include first and second end facets and an active section. The first and second end facets have low reflectivity. The active section is positioned between the first end facet and the second end facet. The active section is configured to generate light that propagates toward each of the first and second end facets. The first end facet is configured to transmit a majority of the light that reaches the first end facet through the first end facet. The second end facet is configured to transmit a majority of the light that reaches the second end facet through the second end facet.

Fiber amplifier having dual output laser diode

An EDFA may include an input photodiode configured to generate a control signal based on an input signal. The EDFA may include a blind stage configured to generate an amplified signal based on the control signal and the input signal. The EDFA may include a non-blind stage configured to generate an output signal based on the amplified signal within the blind stage, the control signal, and a feedback signal. The EDFA may include a filter configured to generate a filtered signal based on the output signal. The EDFA may include an output photodiode configured to generate the feedback signal based on the filtered signal. The EDFA may include an alarm device. A signal within the non-blind stage may be generated based on the feedback signal and the control signal. The alarm device may be configured to generate an alarm signal when the signal exceeds a threshold value.

Blind pump laser detection

An optoelectronic module includes a housing and a printed circuit board ('PCB') positioned within the housing. A positioning member is coupled to the PCB and includes one or more receptacles each configured to receive and secure positioning of an optical component relative to the PCB. The positioning member may include a plurality of receptacles positioned relative to one another in an arrangement defining a vertical array of receptacles, a lateral array of receptacles, or both. In one form, an optical component, when positioned in a receptacle of the positioning member, is spaced from the PCB. The positioning member may be formed of a thermally insulative or thermally conductive material, and a number of optical fibers may be routed between the positioning member and the housing.

Organizer for fiber optic components

An OTDR system utilizes a laser source that is turned 'on' and kept powered until its light reaches the end of the fiber span being measured (i.e., until the fiber span is fully illuminated). At any point in time after the fiber is fully illuminated, the laser source can be turned 'off'. The return (reflected and backscattered) signal is directed into a photodetector of the OTDR, and is measured from the point in time when the fiber span starts to be illuminated. The measurements are made by sampling the return signal at predetermined time intervals&#x2014;defined as the sampling rate. The created power samples are then subjected to post-processing in the form of a differentiation operation to create a conventional OTDR trace from the collected data.

Edge propagating optical time domain reflectometer and method of using the same

An optical amplifier assembly for determining a parameter of an optical fiber configured to amplify an optical signal being propagated therethrough, the assembly comprising: at least one amplifier pump light source assembly configured to transmit light at a plurality of wavelengths into the optical fiber; a receiver configured to receive light that has propagated through at least part of the optical fiber; and a processor configured to determine the parameter of the optical fiber based on the received light.

Method and apparatus for determining optical fibre characteristics

An optical amplifier module is configured as a multi-stage free-space optics arrangement, including at least an input stage and an output stage. The actual amplification is provided by a separate fiber-based component coupled to the module. A propagating optical input signal and pump light are provided to the input stage, with the amplified optical signal exiting the output stage. The necessary operations performed on the signal within each stage are provided by directing free-space beams through discrete optical components. The utilization of discrete optical components and free-space beams significantly reduces the number of fiber splices and other types of coupling connections required in prior art amplifier modules, allowing for an automated process to create a 'pluggable' optical amplifier module of small form factor proportions.

Optical amplifier module

A doped fiber amplifier (e.g., an erbium-doped fiber amplifier&#x2014;EDFA) module is configured to include metrology functionality for performing real-time measurements of the fiber spans connected to the EDFA. In one embodiment, a separate component utilized to perform optical time domain reflectometry (OTDR) measurements is embedded with the EDFA module. The OTDR measurement component includes its own laser source and detector, which are used to analyze the input and output fiber spans associated with the EDFA. In another embodiment, the pump laser of the EDFA is also used as the optical probe light source for the OTDR component, where the source is either 'switched' or 'shared' between performing amplification and providing OTDR measurements. In yet another embodiment, a &#x201c;dual pump&#x201d; source is included with the OTDR component itself and modified to utilize one laser for amplification and the other for OTDR purposes.

Rare earth-doped fiber amplifier with integral optical metrology functionality

An arrangement for providing real-time, in-service OTDR measurements in an optical communication system utilizing distributed Raman amplification. One or more of the laser diodes used to provide the pump light necessary to create optical gain is modified to also generate short duration pulses that ride above or below the conventional pump light. These short duration pulses (which co-exist with the pump light within the optical fiber) are used in performing OTDR measurements, with a conventional processing system used to evaluate reflected pulses and create the actual OTDR measurements.

In-service optical time domain reflectometry utilizing raman pump source

A light source assembly () for emitting depolarized light, and comprising: at least one light source () configured to emit substantially polarized light; and a light depolarizer () arranged to receive light from the light source and comprising a high birefringence optical fiber having a longitudinal core and orthogonal birefringent axes having an angular displacement around the core that varies along the length of the fiber, wherein light emitted from the depolarizer comprises a plurality of polarization states.

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Brixham, United Kingdom

Ian Peter McClean