10results about "Reflectometers dealing with polarization" patented technology

A system for monitoring the strength of optical back-scattering strength along an optical fiber line includes an optical transmitter, a coherent optical receiver, and a processor. The optical transmitter is configured to probe the line with light that is phase-modulated with repetitions of code sequences longer that the round-trip time in the fiber line. The coherent receiver uses homodyne detection to convert light retuned by the optical fiber line to obtain a time sequence of return signal measurements. The processor correlates successive segments of the return signal measurements with the modulation code to obtain a time sequence of intensity response estimates, and generates a back-scattering intensity profile for the optical fiber line by time-averaging corresponding portions of the intensity response estimates.

An optical measurement system in which a coherent light source generates a light signal, and a launch stage receives the light signal from the light source and generates a test signal. The test signal is launched along an optical path. The launch stage includes a first IQ modulator for controlling the test signal. The optical measurement system further includes a local oscillator stage configured to generate a local oscillator signal, wherein local oscillator stage has a second IQ modulator for controlling the local oscillator signal. A detector stage of the system is configured to receive the local oscillator signal from the local oscillator stage and a scattered signal from the optical path, and interfere the local oscillator signal with the scattered signal. The optical measurement system is implemented with one or more photonic integrated circuits.

The present invention relates to a method of re-connecting a first optical fiber (12) with a second optical fiber (34), the first fiber (12) and the second fiber (34) each having a plurality of outer cores, comprising: (a) positioning a first end section of the first fiber (12) and a second end section of the second fiber (34) in proximity so as to be aligned with one another along a longitudinal axis of the first and second end sections in a current connection position including a current connection orientation, in which a current relative rotational angle between the first and second end sections about the longitudinal axis is not known with respect to a relative rotational angle between the first and second end sections in a registered connection orientation determined with respect to a coordinate system during a previous connection of the first fiber (12) with the second fiber (34); (b) optically interrogating the outer cores of the first and second fibers (12, 34) through the current connection position to receive optical signals from the outer cores; (c) modifying, from the optical interrogation of the outer cores, the registered connection orientation such that the first and second fibers in the current connection orientation including the current relative rotational angle between the first and second end sections about the longitudinal axis are correctly registered with respect to the coordinate system.

A fiber rotator system includes a clamp assembly and a fiber rotator assembly for aligning multiple optical fibers. The clamp assembly has a base with fiber channels, fiber clamps, and a guide assembly. The fiber rotator assembly includes a linear actuator and wheel clamps, each aligning with a fiber base channel. Each fiber clamp includes a jaw, connecting rod, spring, and handle, while each wheel clamp includes a linear actuator contactor, wheel jaw, fiber channel rod, and wheel guide. A fiber detection and alignment system analyzes fiber end faces and provides alignment data to a fiber rotator controller. In operation, each wheel clamp contacts and rotates with the linear actuator. The fiber rotator controller selectively engages and disengages the fiber clamps and wheel clamps to iteratively rotate and secure fibers until all fibers are aligned. The system scalably automates alignment of multiple polarization maintaining (PM) fibers with high precision.

An optical measurement system in which a coherent light source generates a light signal, and a launch stage receives the light signal from the light source and generates a test signal. The test signal is launched along an optical path. The launch stage includes a first IQ modulator for controlling the test signal. The optical measurement system further includes a local oscillator stage configured to generate a local oscillator signal, wherein local oscillator stage has a second IQ modulator for controlling the local oscillator signal. A detector stage of the system is configured to receive the local oscillator signal from the local oscillator stage and a scattered signal from the optical path, and interfere the local oscillator signal with the scattered signal. The optical measurement system is implemented with one or more photonic integrated circuits.

The optical fiber sensor includes a setting unit which sets a section to be evaluated set in the optical fiber to one of a first section and a plurality of second sections, each of which is shorter than the first section, an extraction unit which extracts a state change of light from the optical fiber, and a detection unit which detects a change in the surrounding environment based on time-series data of the state change of light in the section to be evaluated.

The invention provides an optical measurement system. The optical measurement system comprises a coherent light source configured to generate a light signal, and a launch stage configured to receive the light signal from the light source and generate a test signal and launch the test signal along an optical path. The launch stage includes a first IQ modulator for controlling the test signal. The optical measurement system further comprises a local oscillator stage configured to generate a local oscillator signal, wherein local oscillator stage comprises a second IQ modulator for controlling the local oscillator signal. A detector stage of the system is configured to receive the local oscillator signal from the local oscillator stage and a scattered signal from the optical path, and interfere the local oscillator signal with the scattered signal. The optical measurement system is implemented with one or more photonic integrated circuits.

A line monitoring system may include a laser source to launch a plurality of pulsed probe signals; an optical transmission system, comprising a plurality of loopbacks, to receive the plurality of pulsed probe signals, and direct the plurality of pulsed probe signals through the plurality of loopbacks. The system may include a receiver to receive a plurality of return signals, derived from the plurality of pulsed probe signals from the transmission system, and a perturbance detection system, coupled to the receiver, to measure a phase difference between a polarization of a pair of return signals of the plurality of return signals. The pair of return signals may be received from a pair of loopbacks of the plurality of loopbacks, from a first loopback and a second return signal from a second loopback. The perturbance detection system may determine a location of a perturbation, based upon the phase difference.

To provide spatially resolved disturbance detection using a line monitoring system.SOLUTION: The line monitoring system may include: a laser source to launch a plurality of pulsed probe signals; and an optical transmission system, comprising a plurality of loopbacks, to receive the plurality of pulsed probe signals, and direct the plurality of pulsed probe signals through the plurality of loopbacks. The system may include a receiver to receive a plurality of return signals, derived from the plurality of pulsed probe signals, from the transmission system, and a disturbance detection system coupled to the receiver and used to measure a phase difference between a polarization of a pair of return signals of the plurality of return signals. The pair of return signals may be received from a pair of loopbacks of the plurality of loopbacks, a first loopback, and a second return signal from a second loopback. The disturbance detection system may determine a location of a disturbance, based upon the phase difference.SELECTED DRAWING: Figure 1

This invention discloses a method and apparatus for detecting the polarization characteristics of optical fibers based on acoustic waves. The method includes: a laser beam emitted from a laser sequentially passes through an aperture stop, a polarizer, and a semi-reflective lens before entering an optical fiber coupler; the optical fiber coupler splits the laser beam into a first beam and a second beam; the first beam is incident on a first Faraday rotator mirror via a first optical fiber; the second beam is incident on a second Faraday rotator mirror via a second optical fiber; the first optical fiber is a bare fiber, and the second optical fiber is tightly wound around a component; the reflected light from the first and second Faraday rotators returns along the original optical path and is coupled through the optical fiber coupler to the semi-reflective lens; an acoustic signal is played onto the second optical fiber tightly wound around the component, while simultaneously muting the first optical fiber; the semi-reflective lens reflects the returned coupled reflected light to an analyzer to obtain polarization information. This invention is used to detect the influence of acoustic wave frequency on the polarization characteristics of optical fibers, helping to ensure the accuracy of optical path transmission.