At&t Bell Laboratories

Lucent Technologies Inc.

Western Electric Company, Inc.

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

At&t Technologies, Inc.

Micron Optics, Inc.

Donald Q Snyder

Harold F Muth, Jr

Robert W Mock, Jr

Andrei Csipkes

John Mark Palmquist

Yufei Bao

Stephen K Ferguson

Felton Davis

Improved fiber Fabry-Perot (FFP) filter configurations are provided in which at least one of the mirror-ended fiber ends forming the FFP has a concave fiber core end. The mirror at that fiber core end is thus concave. The invention provides waferless FFP configurations in which the FFP cavity is an air-gap cavity formed by two highly reflective dielectric mirrors deposited directly on optical fiber ends. The air gap cavity can be tuned using various methods to tune the filter. Use of a concave mirror at the fiber core enables filters with improved performance characteristics: including very wide FSR (&#x3e;12000 GHz), very high finesse (&#x3e;5,000), and high glitch-free dynamic range (GFDR) (&#x3e;40 dB). The invention also provides improved wafer-based FFP fixed and tunable filters that incorporate a concave mirror at a fiber core forming the FFP cavity and a fiber (SMF) waveguide within the cavity.

Waferless fiber Fabry-Perot filters

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 apparatus (19) which is capable of being used in the field is adapted to polish fiber end faces each terminated by a plurality of cylindrically shaped ferrule type connector plugs (30--30). The apparatus includes a platform (50) which includes a plurality of nests (52--52) each adapted to receive a plug such that a plug end face (29) is disposed adjacent to a polishing surface and such that an end portion of fiber which protrudes from each plug engages the polishing surface. Facilities are provided in each nest for applying forces to each plug which may be varied to control the pressure between each fiber end face and the polishing surface and, if desired, subsequently between each plug end face and the polishing surface. Relative motion between the plurality of plugs and the polishing surface is caused to exist such that the polishing surface is turned rotatably while being revolved about an axis to provide uniformly polished fiber end faces. The apparatus also may be used to contour-polish simultaneously a plurality of plugs prior to terminating optical fibers therewith.

Methods of and apparatus for polishing an article

In an apparatus (20) for end finishing an assembly (22) comprising a plurality of lightguide fibers (23--23) positioned between two silicon chips (26--26), a tool carriage (45) is moved past the assembly which at first is held in a fixed position with respect to a path of travel of the carriage. A profiling wheel (110) which is mounted rotatably on the carriage severs a portion of the chips and fibers from the assembly to provide an end portion having a predetermined end configuration. Subsequently, a grinding wheel (131) and a polishing wheel (141) are moved past the newly formed end of the assembly to grind and polish a surface of the end portion and ends of the fibers which terminate in the surface. These last two operations are accomplished while forces are applied to the assembly to bias it toward the tool carriage to provide a controlled pressure and avoid the removal of excess material from the surface and fibers.

Apparatus for end finishing a lightguide fiber termination

Methods of end finishing a lightguide fiber termination

In terminating a ribbon which comprises an array of lightguide fibers, a substrate having a plurality of parallel grooves is positioned in a nest and supported at its end portions after which an end portion of the ribbon is moved longitudinally to cause the fibers to be separated by a comb-like device adjacent one end of the nest after which the ribbon is secured with a clamp adjacent the other end of the nest. Another substrate having aligned grooves is placed over the fibers so that the fibers are held in channels formed by the opposing grooves after which the assembly of substrates and fibers are secured together with a temporary clamp which applies compressive forces to end portions of the assembly along a longitudinal centerline of the assembly. Then a vise which includes jaws having parallel surfaces for engaging the substrate is moved toward the assembly to position a lower jaw under the lower substrate and an upper jaw above the upper substrate. Further motion between the jaws is caused to clamp together the substrates and is controlled to avoid damage to the assembly. The temporary clamp is disengaged from the assembly and the vise is removed to an environment wherein heat transfer into the vise is caused so that a potting compound applied to the assembly fills the interstices thereof to bond together the substrates and fibers.

Methods of and apparatus for terminating a lightguide fiber ribbon

Growing community of inventors

Marietta, GA, United States of America

Donald Q Snyder