Patents Assigned to Exfo Inc.
  • Patent number: 9829429
    Abstract: A polarization-related characteristic of an optical path is determined from a predetermined function of the mean-square of a plurality of differences between polarization-analyzed optical power parameters corresponding to pairs of wavelengths mutually spaced about a midpoint wavelength by a small optical frequency difference. At least some of the said differences correspond to wavelength pairs measured under conditions where at least one of midpoint wavelength, input state of polarization (I-SOP) or analyzed state of polarization (A-SOP) of a pair is different.
    Type: Grant
    Filed: February 14, 2013
    Date of Patent: November 28, 2017
    Assignee: EXFO INC
    Inventors: Normand Cyr, Hongxin Chen, Gregory Walter Schinn
  • Patent number: 9825700
    Abstract: There is provided a method for measuring an optical power attenuation value of a multimode DUT. The method generally has, using an optical source, propagating test light along a multimode device link having a first multimode device, the multimode DUT and a second multimode device serially connected to one another; said propagating including inducing a preferential attenuation of high-order optical fiber modes of the test light along the first multimode device and along the second multimode device; using an optical power detector, detecting an optical signal resulting from the propagation of the test light along the multimode device link and transmitting an output signal based on the detected optical signal; and using a processor, determining the optical power attenuation value of the multimode DUT based on the output signal.
    Type: Grant
    Filed: July 27, 2016
    Date of Patent: November 21, 2017
    Assignee: EXFO INC.
    Inventors: Bernard Ruchet, Gang He
  • Patent number: 9749043
    Abstract: The computer readable memory has recorded thereon instruction code for execution by a computing device for use with an optical power loss measurement (OPLM) system. The instruction code generally comprises: code for displaying a first set of instructions including measuring a first power value of test light outputted from a first reference optical waveguide; code for displaying a second set of instructions including measuring a second power value of test light outputted from a reference waveguide link including the first reference optical waveguide connected in series to a second reference optical waveguide; code for displaying a third set of instructions including measuring a reference power value of the OPLM system resulting from the propagation of light from via the reference waveguide link; and code for determining a corrected reference power value based on the reference power value and on the first and second power values.
    Type: Grant
    Filed: November 16, 2015
    Date of Patent: August 29, 2017
    Assignee: EXFO INC.
    Inventor: Stephane Perron
  • Patent number: 9733616
    Abstract: A portable inspection probe for the inspection of a recessed mating surface of an optical fiber connector is provided. In one variant, the portable inspection probe includes a digital holographic detection module operable to digitally record a hologram of the recessed mating surface, and a rigid probe tip configured to be optically coupled to the digital holographic detection module and shaped to provide optical access to the recessed mating surface. In another variant, the portable inspection probe is to be used with a rigid probe tip connectable thereto, and the digital holographic detection module includes a probing optical assembly not traversed by a reference beam and configured to direct an object beam onto the recessed mating surface and to collect the object beam upon reflection thereof by the recessed mating surface. An inspection system and an inspection method are also provided.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: August 15, 2017
    Assignee: EXFO INC.
    Inventors: Bernard Ruchet, Normand Cyr
  • Patent number: 9709460
    Abstract: The reflectometric method for measuring an optical loss value of an optical fiber link generally comprises: obtaining at least one bias value being indicative of a bias induced by differing backscattering characteristics of a first optical fiber length and a second optical fiber length; propagating at least one test signal serially into the first optical fiber length, the optical fiber link and the second optical fiber length; monitoring at least one return signal resulting respectively from the propagation of the at least one test signal; and determining the optical loss value based on the at least one return signal and the at least one bias value.
    Type: Grant
    Filed: December 18, 2014
    Date of Patent: July 18, 2017
    Assignee: EXFO INC.
    Inventors: Michel Leblanc, Stéphane Perron
  • Patent number: 9673899
    Abstract: There is provided a system and a method for determining an in-band noise parameter representative of the optical noise contribution (such as OSNR) on a polarization-multiplexed optical Signal-Under-Test (SUT) comprising two polarized phase-modulated data-carrying contributions and an optical noise contribution.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: June 6, 2017
    Assignee: EXFO Inc.
    Inventors: Henrik Sunnerud, Mats Skold, Mathias Westlund
  • Patent number: 9673894
    Abstract: There is provided a method of determining at least one linear-crosstalk-related parameter of an optical signal-under-test having, within an optical channel bandwidth, at least a data-carrying signal contribution and a wavelength-dependent linear-crosstalk contribution arising from a data-carrying signal contribution of an adjacent optical signal associated with an adjacent channel to the optical signal-under-test, the method comprising: acquiring at least one optical spectrum trace encompassing a quasi-continuum of closely-spaced wavelengths over a spectral range extending to at least part of both the signal under test and the adjacent optical signal; and estimating said linear-crosstalk contribution using at least spectral properties of said at least one optical spectrum trace; wherein one of said at least one linear-crosstalk-related parameter is the linear-crosstalk contribution and is determined from said estimating.
    Type: Grant
    Filed: May 28, 2012
    Date of Patent: June 6, 2017
    Assignee: EXFO INC.
    Inventors: Daniel Gariepy, Gang He
  • Patent number: 9654213
    Abstract: A portable apparatus for measuring optical powers of optical signals propagating concurrently in opposite directions in an optical transmission path between two elements, at least one of the elements being operative to transmit a first optical signal (S1) only if it continues to receive a second optical signal (S2) from the other of said elements, comprises first and second connector means for connecting the apparatus into the optical transmission path in series therewith, and propagating and measuring means connected between the first and second connector means for propagating at least the second optical signal (S2) towards the one of the elements, and measuring the optical powers of the concurrently propagating optical signals (S1, S2). The measurement results may be displayed by a suitable display unit. Where one element transmits signals at two different wavelengths, the apparatus may separate parts of the corresponding optical signal portion according to wavelength and process them separately.
    Type: Grant
    Filed: March 14, 2016
    Date of Patent: May 16, 2017
    Assignee: EXFO Inc.
    Inventors: Bernard Ruchet, Normand Cyr
  • Patent number: 9641243
    Abstract: A safe-mode OTDR method for characterizing an optical fiber link is provided, as well as an OTDR apparatus operating under such a safe mode. The method includes performing OTDR acquisitions along the fiber link using an OTDR apparatus connected at a proximal end of the optical fiber link, and operating under OTDR acquisition conditions that have been deemed safe for a communication device at a distal end of the fiber link. The obtained reflectometric trace, representing a proximal portion of the optical fiber link, is used to determine a partial-link loss value associated with the proximal portion of the fiber link. Modified acquisition conditions that are safe for the communication device are determined based on the partial-link loss value and on loss-related maximum rating parameters for the communication device. The process is repeated using the modified OTDR acquisition conditions until the end of the link has been reached.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: May 2, 2017
    Assignee: EXFO INC.
    Inventor: Stéphane Perron
  • Patent number: 9596027
    Abstract: There is provided a method and an apparatus for determining quality parameters on a polarization-multiplexed optical signal based on an analysis of the power spectral density of the Signal-Under-Test (SUT). The method is predicated upon knowledge of the spectral shape of the signal in the absence of significant noise or spectral deformation. This knowledge is provided by a reference optical spectrum trace. Based on this knowledge and under the assumption that ASE noise level is approximately constant in wavelength over a given spectral range, the spectral deformation of the signal contribution of the SUT may be estimated using a comparison of the spectral variations of the optical spectrum trace of the SUT with that of the reference optical spectrum trace.
    Type: Grant
    Filed: May 2, 2014
    Date of Patent: March 14, 2017
    Assignee: Exfo Inc.
    Inventors: Gang He, Daniel Gariepy, Mats Skold
  • Patent number: 9571186
    Abstract: An OTDR device and method for characterizing one or more events in an optical fiber link are provided. A plurality of light acquisitions is performed. For each light acquisition, test light pulses are propagated in the optical fiber link and the corresponding return light signals from the optical fiber link are detected. The light acquisitions are performed under different acquisition conditions, for example using different pulsewidths or wavelengths. Parameters characterizing the event are derived using the detected return signal from at least two of the plurality of light acquisitions.
    Type: Grant
    Filed: September 21, 2015
    Date of Patent: February 14, 2017
    Assignee: EXFO INC.
    Inventors: Stéphane Perron, Michel Leblanc
  • Patent number: 9549470
    Abstract: There is provided an adapter device for connecting and interfacing a transceiver module in conformance with first mechanical specifications and first connector specifications into a host socket adapted to receive transceiver modules in conformance with second mechanical specifications and second connector specifications.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: January 17, 2017
    Assignee: EXFO Inc.
    Inventors: Michel Blier, Patrick Begin, Sergio Prestipino
  • Patent number: 9506838
    Abstract: There is provided a bi-directional optical reflectometric method for characterizing an optical fiber link.
    Type: Grant
    Filed: August 7, 2015
    Date of Patent: November 29, 2016
    Assignee: EXFO Inc.
    Inventors: Mario L'Heureux, Michel Leclerc, Eric Thomassin, Stephane Perron
  • Patent number: 9450854
    Abstract: Method and test device for performing testing in a network conveying a plurality of traffic flows. At the test device, receiving traffic flows through a first interface of the test device on a first segment and forwarding the received plurality of traffic flows towards a second segment of the network through a second interface. At the test device, receiving a test request directed to an address of a test module and, in response to the test request, causing a sequence of proprietary traffic to be injected on the second segment. A reprogrammable test device comprising a networked test module at least in part on a reprogrammable partition of a programmable logic device and a reprogramming module, on a static partition of the programmable logic device, for reprogramming at least a portion of the reprogrammable partition implementing the test module in accordance with reprogramming data received at the test device.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: September 20, 2016
    Assignee: EXFO Inc.
    Inventors: Sylvain Nadeau, Sébastien Prieur, Dominic Lapierre
  • Patent number: 9438336
    Abstract: There is provided a method for determining a noise parameter characterizing an optical Signal-Under-Test (SUT) having a signal contribution, an Amplified Spontaneous Emission (ASE) noise contribution and a non-ASE optical noise contribution, such as a carrier-leakage contribution or a depolarized-signal contribution, within an optical-signal bandwidth. The method comprises acquiring optical spectrum trace(s) of the SUT, discriminating at least the non-ASE optical noise contribution from the ASE-noise contribution using the optical spectrum trace(s) and/or a trace obtained from the optical spectrum trace(s); and determining the noise parameter using discriminated non-ASE optical noise contribution and/or the discriminated ASE-noise contribution.
    Type: Grant
    Filed: August 13, 2013
    Date of Patent: September 6, 2016
    Assignee: EXFO INC.
    Inventors: Gang He, Daniel Gariepy, Hongxin Chen, Bernard Ruchet
  • Patent number: 9432206
    Abstract: A method and apparatus for testing network links bi-directionally and independently employ local test apparatus (1000) at one end of the link (1105, 1110, 1115) and remote test apparatus (1200) at the opposite end of the link. The local test apparatus transmits test traffic to the remote test apparatus which analyzes the test traffic to determine characteristics of the link in the local-to-remote direction. While the analysis is taking place, the remote test apparatus transmits interim test results to the local test apparatus, i.e., while the remote test apparatus is still running the test and without disrupting the test. Preferably, the remote test apparatus transmits test traffic to the local test apparatus which the latter analyzes to determine characteristics of the link in the remote-to-local direction. The local test apparatus may report the test results for both directions. The network may be a connected or connectionless network.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: August 30, 2016
    Assignee: EXFO Inc.
    Inventors: Bruno Giguere, Isabelle Piette, Michel Grenier
  • Patent number: D788612
    Type: Grant
    Filed: February 11, 2016
    Date of Patent: June 6, 2017
    Assignee: EXFO INC.
    Inventors: Denis Lafrance, Antoine-Alexandre Michaud
  • Patent number: D796522
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: September 5, 2017
    Assignee: EXFO INC.
    Inventors: Mario L'Heureux, Félix Gaudreault, Benoît Fellice, Jean-François Drolet, Laurence Choquet
  • Patent number: D796524
    Type: Grant
    Filed: February 15, 2016
    Date of Patent: September 5, 2017
    Assignee: EXFO INC.
    Inventor: Jean-Sébastien Martel
  • Patent number: D798171
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: September 26, 2017
    Assignee: EXFO INC.
    Inventors: Michel Blier, Patrice Gonay, Sebastien Nadeau, Pascal Recoura-Massaquant