1032results about "Testing fibre optics/optical waveguide devices" patented technology

The invention relates to a monitor for monitoring at least one optical signal parameter in an opticl fibre having an access region of reduced cladding sufficient to allow access to the evanescent field. The monitor includes an optical element mountable adjacent to the access region of an optical fibre which optical element is capable of obtaining access to the evanescent field to enable use of the data therein to derive the at least one optical signal parameter.

The disclosed automatic calibration systems and methods provide a repeatable way to detect internal catheter reflections and to shift the internal catheter reflections to calibrate an image.

An optical switching assembly selectively connects an optical source and a detector to at least one fiber optic device. The assembly includes first and second groups of optical paths, and first and second optical switches. The first optical switch selectively connects the optical source to one end of the first group of optical paths, and the second optical switch selectively connects the detector to the one end of the second group of optical paths. The assembly laos includes a plurality of junctions, each having a lead associated therewith, and one or more of the leads are connected to the fiber optic device. The junctions connect the other end of the first group of optical paths and the other end of the second group of optical paths to the lead to facilitate the testing of the fiber optic device.

The disclosed automatic calibration systems and methods provide a repeatable way to detect internal catheter reflections and to shift the internal catheter reflections to calibrate an image.

A method is provided for computing a composite image representing a focused image of an object in an application of machine vision in an optical inspection system. An image tessellated into focus regions is evaluated by region for fine feature sharpness. A sharpness image is computed for each focused region using a fine feature sharpness measurement. A focused composite image is computed by combining as a weighted average, the images at several focus settings, using the sharpness image at each focus setting as the weight. The focused composite image can be further analyzed, inspected, or otherwise processed.

An optical receiver may include a photodetector that is configured to generate an electrical signal in response to detecting an optical signal, a first gain path coupled to receive and amplify the electrical signal generated by the photodetector, and a second gain path coupled to receive and amplify the electrical signal generated by the photodetector. The second gain path may have a higher gain than the first gain path. The two gain paths may be configured to amplify the electrical signal independently of each other. The optical receiver may also include a switch that selectably outputs an amplified electrical signal from one of the gain paths based on a magnitude of a signal corresponding to the optical signal.

A mechanical splice fiber optic connector installation tool operable for performing splice terminations and verifying an acceptable splice termination includes a power source, a connector holder, an integrated Visual Fault Locater having an optical transmission element and a display for displaying the status of the termination. An adapter configured to receive the connector and align the connector with the optical transmission element, such that the optical transmission element is spaced apart from the connector at a predetermined distance and is in optical communication with the connector for propagating light energy through the adapter and along the stub optical fiber to a termination area of the connector.

A system for monitoring a liquid level in an aircraft shock strut includes a cylinder having an internal chamber sealed by a piston telescopically movable within the cylinder. The chamber contains a gas and a liquid, and a sensor assembly is provided for monitoring a condition of a level of the liquid in the chamber. The sensor assembly includes at least one probe within the chamber, and a fitting assembly allows one or more leads from the probe to pass through the wall of the strut while maintaining pressure in the chamber. The fitting assembly includes a plug molded to the one or more leads extending from the probe. The fitting assembly also includes a retainer for holding the plug in sealed relationship with a through passage in the strut.

Embodiments of the invention include an active optical cable and method for controlling the operation of the active optical cable based on the detection of signal loss, e.g., due to fiber breakage, within the active optical cable. The active optical cable includes first and second optical transceivers, each with an open fiber control module coupled between the transmission side and the receiver side of the respective optical transceiver. The transmission side of each optical transceiver is coupled to the receiver side of the other optical transceiver via a plurality of transmission channels, such as a plurality of optical fibers. Each open fiber control module is configured to detect an optical power level of an optical signal received by the receiver side of the optical transceiver within which the open fiber control module resides and, based on such detection, control the operation of the corresponding transmission side of the optical transceiver.

A method and system for rendering the shape of a multi-core optical fiber or multi-fiber bundle in three-dimensional space in real time based on measured fiber strain data. Three optical fiber cores arc arranged in parallel at 120° intervals about a central axis. A series of longitudinally co-located strain sensor triplets, typically fiber Bragg gratings, are positioned along the length of each fiber at known intervals. A tunable laser interrogates the sensors to detect strain on the fiber cores. Software determines the strain magnitude (ΔL/L) for each fiber at a given triplet, but then applies beam theory to calculate curvature, beading angle and torsion of the fiber bundle, and from there it determines the shape of the fiber in s Cartesian coordinate system by solving a series of ordinary differential equations expanded from the Frenet-Serrat equations. This approach eliminates the need for computationally time-intensive curve-tilting and allows the three-dimensional shape of the optical fiber assembly to be displayed in real-time.

A method, apparatus and system for minimally intrusive fiber identification includes imparting a time-varying modulation onto an optical signal propagating in an optical fiber and subsequently detecting the presence of the time-varying modulation in the optical signal transmitting through the fiber to identify the fiber. In a specific embodiment of the invention, a time-varying curvature is imposed on the fiber to be identified and the presence of the resultant time variation in the transmitted power of a propagating optical signal is subsequently detected for identification of the manipulated fiber.

A wireless sensor system includes a passive sensor apparatus configured to be embedded within a concrete structure to monitor infiltration of contaminants into the structure. The sensor apparatus includes charging circuitry and a plurality of sensors respectively configured to measure environmental parameters of the structure which include information related to the infiltration of contaminants into the structure. A reader apparatus is communicatively coupled to the sensor apparatus, the reader apparatus being configured to provide power to the charging circuitry during measurements of the environmental parameters by the sensors. The reader apparatus is configured to independently interrogate individual ones of the sensors to obtain information measured by the individual sensors. The reader apparatus is configured to generate an induction field to energize the sensor apparatus. Information measured by the sensor apparatus is transmitted to the reader apparatus via a response signal that is superimposed on a return induction field generated by the sensor apparatus. Methods of monitoring structural integrity of the structure are also provided.

A method of testing a planar lightwave circuit is achieved by coupling an optical probe to the planar lightwave circuit. In one embodiment, a second probe is used in combination with the first probe to test the planar lightwave circuit by sending and receiving a light beam through the planar lightwave circuit.

A waveguide fabrication method including the steps of providing a substrate including at least one waveguide recess structure and a stress release recess structure for receiving a waveguide material, and depositing the waveguide material onto the substrate and into both the waveguide recess structure and the stress release recess structure.

The location of a physical disturbance along an optical waveguide is determined by measuring different propagation times for the resulting phase variation to propagate to phase responsive receivers at ends of bidirectional signal paths. Each receiver can have a coupler that functions as a beam combiner and as a beam splitter inserting the opposite signal. On each receiving end, the coupler provides one or more detectors with signals from which phase related independent variable values are taken, processed and mapped to phase angles. Relative phase angle versus time is derived for each opposite signal pair and correlated at a time difference, i.e., a difference in propagation time from which the location of the disturbance is resolved. Polarization sensitive and polarization insensitive examples are discussed with various optical fiber arrangements.

Problems of excessive fading in systems for monitoring single-mode optical fiber for physical disturbances are addressed by launching into the fiber polarized light having at least two different predetermined launch states of polarization whose respective Stokes vectors are linearly-independent of each other; downstream from the first location, receiving the light from the fiber; analyzing the received light using polarization state analyzer means having at least two different analyzer states of polarization that are characterized by respective Stokes vectors that are linearly-independent of each other and detecting the analyzed light to provide corresponding detection signals; deriving from the detection signals measures of changes in polarization transformation properties of the fiber between different times that are substantially independent of said launch states and said detection states; and, on the basis of predefined acceptable physical disturbance criteria determining whether or not the measures are indicative of a reportable physical disturbance.