Lucent Technologies Inc.

American Telephone and Telegraph Company, At&t Technologies, Inc.

At+t Corp.

At&t Bell Laboratories

American Telephone & Telegraph Co., At&t Bell Laboratories

At&t Technologies, Inc.

John Mark Palmquist

Andrei Csipkes

Ian A White

Muid Ur-Rehman Mufti

Ralph A Treder, Jr

Behzad Shahraray

Richard Joseph Pimpinella

Frank Salvatore Leone

Randy Alan Reagan

William Joseph Parzygnat

Joel Leslie Mock

Donald Q Snyder

Arthur T Schmidt, Iii

Morton Jefferson Saunders

Susan S Sachs

Thomas L Williford, Jr

Joseph S Kovalchick

Felton Davis

Robert P Lyons

A segment detection system automatically, contactlessly, rapidly, and precisely detects a segment along an edge, such as a boundary, of an object in a digitized image. The segment detection system includes an imager for capturing an image of an object and converting the image into an electrical signal. A computer is connected to the camera for receiving the electrical signal. A machine vision system is associated with the computer and is adapted to analyze the image. A segment detection program is disposed in the computer for driving the computer and the machine vision system in accordance with the present invention. The segment detection program includes an initialization subroutine and a matching subroutine. The initialization subroutine configures the program to search for a particular target polynomial equation. The matching subroutine derives a test polynomial equation that represents a test segment from a test edge of the object based upon an analysis of the image. Further, the matching subroutine determines whether the test segment matches the target segment by comparing corresponding coefficients of the test polynomial equation and the target polynomial equation.

Segment detection system and method

An improved fiber optic cable connector is provided that exhibits a consistent return loss rating of 60 dB or better. The connector comprises matable connector housings that terminate the ends of respective optical cables to be joined. Within each housing, the optical fiber of the respective cable is secured within a ceramic ferrule that extends axially of the connector. The endface of each optical fiber is exposed at the end of its respective ferrule. The ends of the ferrules are ground and polished in such a way that the endfaces of the optical fibers exhibit a planar undercut with respect to the lip of the axial passageway in which the fibers are secured. When the ferrules are brought and pressed together end-to-end as the connectors are mated, the material of each ferrule compresses until the endfaces of the optical fibers engage each other with near null pressure. The result is the near elimination of pressure on the optical fiber itself, which avoids a density and index of refraction change at the junction and thus improves return loss performance.

Fiber optic connector with improved return loss performance

An insertion loss determination system contactlessly and automatically determines an insertion loss of an optical fiber connector having a domed combination of an optical fiber and a surrounding support ferrule. The system is suitable for a fully automated connector assembly line. In structure, the system comprises (a) a core-to-ferrule eccentricity (CFE) inspection system configured to determine a CFE parameter corresponding with an offset between a fiber center and a ferrule center; (b) a fiber light intensity tester (FLIT) configured to determine a FLIT parameter corresponding with an amount of a reference light that fails to pass through the fiber; and (c) an insertion loss evaluation system configured to determine an insertion loss of the connector based upon the parameters. The evaluation system may further be configured to identify an insertion loss class, for example, very good, good, or bad, based upon the insertion loss.

System and method for contactlessly and automatically determining the

An improved fiber optic cable connector is provided that exhibits a consistent return loss rating of -60 dB or better. The connector comprises matable connector housings that terminate the ends of respective optical cables to be joined. Within each housing, the optical fiber of the respective cable is secured within a ceramic ferrule that extends axially of the connector. The endface of each optical fiber is exposed at the end of its respective ferrule. The ends of the ferrules are ground and polished in such a way that the endfaces of the optical fibers exhibit a planar undercut with respect to the lip of the axial passageway in which the fibers are secured. When the ferrules are brought and pressed together end-to-end as the connectors are mated, the material of each ferrule compresses until the endfaces of the optical fibers engage each other with near null pressure. The result is the near elimination of pressure on the optical fiber itself, which avoids a density and index of refraction change at the junction and thus improves return loss performance. A method of fabricating such a fiber optic cable connector is also provided.

Fiber optic connector with improved loss performance and method for

An offset determination system and method permit accurate calculation of an offset of a central feature of an object. The offset determination system and method are particularly suited for, but not limited to, an automatic inspection system for determining the eccentricity of an optical fiber core relative to a theoretical ideal center of an optical fiber termination. The core is extremely smaller (typically between about 50 and 500 times) in size than the termination boundary. An inspection system has a feature imager, one or more boundary segment imagers but preferably four in number, and a machine vision system connected to the foregoing imagers. The feature imager is positioned to capture an image of the feature (e.g., fiber core endface), and the one or more boundary segment imagers are positioned to capture an image of a corresponding boundary segment of the object (e.g., termination endface). The machine vision system determines the offset, or eccentricity, based upon the feature image, the one or more boundary segment images, and the offset determination system and method.

Eccentricity determination system and method for accurately computing an

A surface analysis system can contactlessly, automatically, and rapidly detect, classify, and evaluate a surface of an object, particularly, an optical fiber end face, for discontinuities to derive a single pass/fail conclusion regarding the surface. The surface analysis system has a scope for capturing an image of the end face. A computer is connected to the scope. A machine vision system is associated with the computer for receiving the image. A surface analysis program is associated with the computer for driving the machine vision system. The program searches for any discontinuities in the image by analyzing each pixel and a corresponding pixel structure of pixels to determine whether a discontinuity resides at each pixel. Discontinuities are classified as one of the following: binary thresholds, local gradients, and directional gradients. The pixel structure includes a plurality of pixels that were previously analyzed. The program determines whether the surface is continuous based upon any discovered discontinuities.

Surface analysis system and method

The present invention is an optical monitoring and test access interconnection module especially adapted for use with a fiber optic distribution frame for a fiber optic communications system. The interconnection module provides a combination of monitoring and test access for two fiber lines, typically a transmit/receive pair, where wavelength division multiplexer (WDM) test access is provided to both the transmit and receive fibers. In one embodiment of the present invention, the interconnection module monitors only the receive fiber line where a power monitoring circuit receives a monitor level optical signal via an optical tap and converts the optical signal to an electrical output. Processing electronics and firmware within the module are operable to generate alarms and other control signals when changes in the power level of the received signal are detected. A test access path is provided on the module for use, for example, with an optical time domain reflectometer (OTDR). In one embodiment of the present invention, the interconnection module incorporates a unique physical design arrangement that separates the optical signal processing from the electronic processing into partitioned sub-modules. The optical and electronic sub-modules may advantageously be assembled (and dis-assembled) by means of guides that allow the module halves to slide together. A unique optical mating connector is provided in the sliding arrangement to join the optical module to an opto-electronic photodetector in the electronic module.

Optical monitoring and test access module

An automatic inspection method contactlessly measures the offset of a feature of an object from a theoretical ideal center of the object, and is particularly suited for measuring at an endface of an optical fiber termination the eccentricity of an optical fiber core relative to a theoretical ideal center of the termination. The core is extremely smaller (typically between about 50 and 500 times) in size than the termination boundary. An inspection system for implementing the novel inspection method has a feature imager, one or more boundary segment imagers but preferably four in number, and a machine vision system connected to the foregoing imagers. The feature imager is positioned to capture an image of the feature (e.g., fiber core endface), and the one or more boundary segment imagers are positioned to capture an image of a corresponding boundary segment of the object (e.g., termination endface). The machine vision system determines the offset, or eccentricity, based upon the feature image and the one or more boundary segment images.

Automatic inspection method for contactlessly measuring an offset of a

A balanced focus system and method achieve optimal focus of different areas of an object that are concurrently imaged and then combined to form a combined image. The balanced focus method is particularly suited for, but not limited to, use with an automatic inspection system for contactlessly measuring at an endface of an optical fiber termination the eccentricity of an optical fiber core relative to a theoretical ideal center of an alignment surface of the termination. The inspection system has an imaging system with a feature imager and one or more boundary segment imagers but preferably four in number, a focus adjustment mechanism (FAM) for adjusting the position of the imagers relative to the imaged object along an optical axis, and a machine vision system for receiving image data from the foregoing imagers and configured to control the FAM. The feature imager is positioned to capture an image of the feature (e.g., fiber core endface), and the one or more boundary segment imagers are positioned to capture an image of a corresponding boundary segment of the object (e.g., termination endface). The machine vision system determines the eccentricity based upon the feature image and the one or more boundary segment images. Significantly, the machine vision system employs the balanced focus system and method to achieve an optimal focus position for the imaging system based upon a series of combined images and a statistic S that is computed for each of the sampling locations.

Balanced focus system and method for achieving optimal focus of

An automatic inspection system contactlessly measures the offset of a feature of an object from a theoretical ideal center of the object, and is particularly suited for measuring at an endface of an optical fiber termination the eccentricity of an optical fiber core relative to a theoretical ideal center of the termination. The core is extremely smaller (typically between about 50 and 500 times) in size than the termination boundary. An inspection system has a feature imager, one or more boundary segment imagers but preferably four in number, and a machine vision system connected to the foregoing imagers. The feature imager is positioned to capture an image of the feature (e.g., fiber core endface), and the one or more boundary segment imagers are positioned to capture an image of a corresponding boundary segment of the object (e.g., termination endface). The machine vision system determines the offset, or eccentricity, based upon the feature image and the one or more boundary segment images.

Automatic inspection system for contactlessly measuring an offset of a

A return loss determination system contactlessly and automatically determines a product-to-product return loss of an optical fiber connector having a domed optical fiber termination endface (i.e., an endface having an optical fiber and a surrounding support ferrule). The return loss determination system includes (a) an undercut/protrusion (U/P) inspection system for determining a U/P parameter corresponding with an offset of the fiber relative to a curvature of the ferrule along an axis of the fiber, (b) a dome polish eccentricity (DPE) inspection system for determining a DPE parameter corresponding with a displacement in a plane perpendicular to the axis between a curvature center of the curvature and a fiber center of the fiber, (c) a curvature radius (CR) inspection system for determining a CR parameter corresponding with a radius of the curvature relative to the curvature center, (d) a discontinuity inspection system for determining a discontinuity parameter to quantify surface discontinuities in the fiber, and (e) a return loss evaluation system for determining a return loss of the connector based upon the parameters.

An alignment and lighting system aligns and lights an optical fiber termination so that an inspection system can measure the eccentricity of an optical fiber core relative to the termination. The inspection system has an imaging system comprising a feature imager and one or more boundary segment imagers but preferably four in number, a machine vision system connected to the imaging system, and an alignment and lighting system for aligning the termination with the imaging system and lighting the termination without having to launch light therethrough. The feature imager is positioned to capture an image of the fiber core endface, and the one or more boundary segment imagers are positioned to capture an image of a corresponding boundary segment of the termination endface. The machine vision system determines the offset, or eccentricity, based upon the feature image and the one or more boundary segment images. The alignment and lighting system includes an alignment apparatus and a unique lighting scheme. The alignment apparatus has a plurality of alignment arms that are spaced apart via spacings to form a cross-shaped aperture that is engaged with the termination endface. Light is projected toward the exposed regions at a light projection angle that is outside the light acceptance angle associated with the fiber core. As a result, light is not generally received by the core, and light is scattered within and reflects out from the fiber cladding and the termination support material surrounding the cladding.

Alignment and lighting system and method for aligning and lighting an

A zone analysis system and method (211) optimize speed and minimize adverse effects resulting from noise in an inspection system (90) for measuring disparity between two surfaces. In particular, the zone analysis system and method (211) can be implemented in an inspection system (90) for contactlessly measuring undercut or protrusion of an optical fiber (26) relative to a surrounding support material (36) at the endface (79) of an optical fiber termination (37). In structure, the inspection system (90) has a measurement apparatus (91) with an interferometer (98) controlled by a machine vision system (92) for determining the degree of disparity. The inspection system (90) measures an offset of an interferometric fringe (113') produced by the interferometer (98) over the target (82) in the image in order to determine the disparity. Further, the machine vision system (92) employs the zone analysis system and method (211) for optimizing the performance thereof.

Zone analysis system and method for optimizing the performance of an

A self-calibration system and method (125) determines the adequacy of an interferometer angle .phi. and surface curvatures in an inspection system (90). The inspection system (90) can contactlessly measure the disparity between two surfaces, such as the undercut or protrusion of an optical fiber (26) relative to a surrounding support material (36) at the endface (79) of an optical fiber termination (37). The inspection system (90) measures an offset of the fringe (113') in the image over the target (25') in the image (111a, 111b, 111c) in order to determine the disparity. In structure, the inspection system (90) has a measurement apparatus (91) with an interferometer (98) situated at the angle .phi. relative to the target (82) controlled by a machine vision system (92) for determining the degree of disparity. Further, the machine vision system (92) preferably employs the self-calibration system and method (125).

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Lilburn, GA, United States of America

John Mark Palmquist