Lucent Technologies Inc.

Fitel USA Corporation

The University of Sydney

Agere Systems Guardian Corp.

Furukawa Electric North America, Inc.

Benjamin John Eggleton

John A Rogers

Paul S Westbrook

Thomas Andrew Strasser

Paul Steinvurzel

Robert Scott Windeler

Rolando Patricio Espindola

Arturo Hale

Gadi Lenz

Charles Kerbage

Sungho Jin

Karl Raymond Amundson

Hareesh Mavoori

Laura Ellen Adams

Kenneth Stephen Feder

David John DiGiovanni

Jefferson L Wagener

Kenneth L Walker

Richart Elliott Slusher

Rebecca Jane Jackman

Jon W Engelberth

Clifford E Headley

Sandra Greenberg Kosinski

Peter Mach

Mark David Pelusi

Juhi Chandalia

Ashish Ahuja

Xiang Liu

Daniel Mahgerefteh

Toshio Kimura

Stefan Hunsche

Shu Namiki

Yoshihiro Emori

Ashish Madhukar Vengsarkar

Thomas G Brown

Mikhail Sumetsky

Akira Fujisaki

Gregory Raybon

Kirk William Baldwin

Torben N Nielsen

Chunhui Xu

Herbert Haunstein

Steven Herbert Simon

Mikhail Sumetskiy

Justin Boyd Judkins

Glen Robert Kowach

Matthias Berger

Carl Edmund Soccolich

Stephan Wielandy

Pierre Wiltzius

Anatoli A Abramov

Sharad Ramanathan

Rajan D Deshmukh

Tsing Hua Her

David James Moss

Michael Sumetsky

Richard J Ramsay

Justin D Ging

Stefan Heinz Spalter

Trung Duc Vo

William Peter Corcoran

Misha Sumetsky

Andreas Munk

Mikio Ogai

Jochen Bernhard Schroeder

Dane Austin

Akheelesh Abeeluck

Carel Martijn De Sterke

Abds-Sami Malik

Jeremy Bolger

Jean-Christophe Bouteiller

Feng Luan

Robert A Macharrie

Dong-Il Yeom

Pavel Ivanoff Reyes

Timothy Iredale

Torben N Nielson

Geoffrey L Burdge

Akira Fujisakii

This invention concerns real-time multi-impairment signal performance monitoring. In particular it concerns an optical device, for instance a monolithic integrated photonics chip, comprising a waveguide having an input region to receive a signal for characterization, and a narrow band CW laser signal. A non-linear waveguide region to mix the two received signals. More than one output region, each equipped with bandpass filters that extract respective discrete frequency bands of the RF spectrum of the mixed signals. And, also comprising (slow) power detectors to output the extracted discrete frequency banded signals.

Photonic monitoring for optical signals

A method and apparatus for providing optical supercontinuum. The method comprises creating a spectrally narrow phase feature within a supercontinuum spectrum produced from a laser pulse that has been subjected to supercontinuum generation, thereby producing a modified supercontinuum spectrum, and propagating the modified supercontinuum spectrum through an optical waveguide that is suitable for supercontinuum generation, thereby further modifying the modified supercontinuum spectrum. The method may include modifying the modified supercontinuum spectrum by increasing its energy in a vicinity of the phase feature.

Tunable optical supercontinuum enhancement

An optical noise monitoring method and monitor, the monitor comprising an optical transmitter for receiving at least a portion of an optical signal, a device arranged to extract a reflected optical signal comprising a portion of the optical signal back-reflected by stimulated Brillouin scattering in the optical transmitter, and a photodetector for receiving the reflected optical signal. The optical transmitter can scatter the optical signal by stimulated Brillouin scattering.

Optical signal to noise monitor

A microstructured optical waveguide is formed to include a periodic sequence of 'plugs' of optically active material within the inner cladding air tunnels. The plugs are utilized as a grating structure for generating resonant and periodic structures. The waveguide (in one embodiment, an optical fiber) is tunable by changing the spacing of the plugs (e.g., heating the structure, changing the pressure within the structure, etc.), or by modifying the initial spacing of the plugs during the formation of the microstructured optical waveguide (i.e., by modifying the 'dipping frequency' of the waveguide into a reservoir of optically active material). In general, any number of different types of optically active material may be used to form the plugs, where two or more different materials may be used in the same structure, and introduced in an alternating fashion.

Microstructured optical waveguide for providing periodic and resonant structures

Embodiments of the invention include system for monitoring the effectiveness of pulse shaping in a nonlinear optical fiber (). The spectral content of the pulse, after passing through the nonlinear fiber (), provides an indication of how effectively the pulse was regenerated. A portion of the pulse exiting the nonlinear fiber is tapped off and its pulse energy is measured in at least one selected spectral region. The selected spectral region is one in which the pulse tends to gain energy when effective regeneration is taking place. The information concerning the effectiveness of pulse shaping in a nonlinear optical fiber is fed back to dynamically change the residual dispersion at the regenerator input. The spectral measurement leads to a control signal () to indicate a level of performance of the system, or to improve the performance of the system by adjusting an operational parameter.

Nonlinear device comprising a spectrally broadening fiber

A tunable optical fiber device comprises a length of fiber having a core having a certain refractive index; a cladding peripherally surrounding the core with a refractive index less than the refractive index of the core; and at least one hollow region disposed within the cladding in proximity to the core or within the core itself. Fluid (typically liquid) controllably moved within the hollow region modifies the effective index of the fiber and thereby tunes its characteristics.

Tunable microfluidic optical fiber devices and systems

In accordance with the invention, the fabrication of a grating phase mask is improved by providing a multiple-scan exposure which can provide an accumulated exposure that is effectively phase modulated or modulated rapidly in amplitude. Applicants have determined that exposure scans can be chosen so that each is modulated in amplitude and without modulation in phase, but the accumulated exposure of the multiple scans is modulated in phase and/or modulated in amplitude. The improved method can be used to make phase masks for fabrication of sophisticated fiber gratings such as superstructure gratings.

Method of making gratings and phase masks for fiber grating fabrication

In accordance with the invention, an optical fiber communication system is provided with a tunable linearly chirped Bragg grating in high birefringence fiber for reduction of polarization mode dispersion without increasing chromatic dispersion. A first embodiment using a single grating can be tuned for optimal PMD compensation, optimal chromatic compensation or optimal simultaneous compensation. Alternative embodiments using a plurality of gratings permit simultaneous compensation of both PMD and chromatic dispersion.

Optical fiber communication systems having simultaneous compensation of polarization mode dispersion and chromatic dispersion

A microstructured optical component is formed from an optical preform fabricated to include one ore more internal regions of differing refractive index. The preform is drawn into a fiber and sliced into relatively long individual fiber segments, each segment thus forming a microstructured optical component. An optical signal may then be coupled through a sidewall of the component in a direction parallel to the endfaces of the segment. A more complex structure can be formed by grouping together a plurality of fiber segments and performing an additional drawing and slicing process.

Optical devices including microstructured fiber sections disposed for transverse signal propagation

In accordance with the invention, a modulated RZ pulse source comprises a modulated light source optically coupled to a stabilized Bragg grating filter and one or more optical taps. The light source is preferably modulated in power and frequency and has an adjustable channel wavelength &#x3bb;. The Bragg grating filter has a reflectivity bandwidth having a high slope reflectivity cutoff and is preferably tunable. A feedback arrangement responsive to the taps keeps the source channel wavelength &#x3bb; on the edge of the reflectivity bandwidth for shaping RZ pulses. When the Bragg grating is stabilized, the feedback system maintains &#x3bb; at a value linked to the grating reflectivity edge and, by overlapping at least part of the optical spectrum of the source, converts the modulated source light into RZ pulses with high extinction ratio (&#x2267;12 dB). The result is a high power, jitter-free RZ pulse source that is compact, inexpensive and power efficient.

Optical pulse source for long haul optical communication systems

The specification describes a wavelength monitoring system for multiple wavelength communications systems, such as WDM systems, based on the recognition that the mechanism for spatially separating the individual wavelength bands can be achieved within the optical fiber itself. Individual wavelength bands are separated using a series of discrete gratings spaced longitudinally along the fiber core. The wavelength bands are extracted from the fiber core by converting the energy in the selected band from a core-guided mode to a radiation mode. By using a tilted grating, the light in the radiation mode is directed through the cladding and out of the fiber. Spatial resolution of the selected bands can be any desired physical length. An important implication of this is that detection can be made in the near field using inexpensive detecting apparatus. Near field is defined for convenience in this case as the optical field of the radiated energy without any optically modifying elements (collimating devices, diffraction elements, mirrors, etc.). This eliminates nearly all of the optics, and the attendant expense, in prior art monitoring systems.

Wavelength monitoring optical fibers using detection in the near field

A colorless tunable dispersion compensator (TDC) comprises a plurality of N separate dispersion compensation elements, each centered at a different wavelength used in the communication system. A single tuning element is coupled to the plurality of separate dispersion compensation elements. A 1-out-of-N selector (such as a 1&#xd7;N optical switch) is used to select the particular tunable dispersion compensation element to be implemented for an associated channel in the system. Advantageously, the same TDC can then be used in association with each channel in the communication system, as controlled by the 1-out-of-N selector to chose the particular compensation element for a specific channel wavelength.

Colorless tunable dispersion compensator

A filled-core optical fiber and method where the optical fiber is collapsed at opposing ends subsequent to the active optical material being introduced into the hollow core region. The collapsing-functions to &ldquo;pinch off&rdquo; the active material (which may be a liquid or solid) within the fiber structure and also collapse the cladding layer ring surrounding the core into a solid core region on either side of the active material. The filled-core fiber is then sealed and can be coupled to standard fiber using conventional splicing processes.

Filled-core optical fiber and method of making the same

A multi-wavelength cascaded Raman resonator (&ldquo;MWCRR&rdquo;). The MWCRR has an optical source for pumping optical radiation centered around an input wavelength. The MWCRR further includes a Raman fiber having at least a first set of optical gratings for converting the pumped optical radiation to wavelengths other than the input wavelength. The Raman fiber also has at least one adjustable output coupler having a variable reflectivity for controlling the power of the optical radiation propagating from the at least one set of optical gratings at the wavelengths other than the input wavelength.

Multiwavelength cascaded raman resonator

Embodiments of the invention include an optical fiber device such as a tunable birefringent optical fiber having a core region, a cladding layer therearound, and a controllable active material disposed in, e.g., selective capillaries or pockets formed in the cladding layer. The active materials include, e.g., electro-optic material, magneto-optic material, photorefractive material, thermo-optic material and/or materials such as laser dyes that provide tunable gain or loss. The application of, e.g., temperature, light or an electric or magnetic field varies optical properties of the active material, which, in turn, varies or affects the propagation properties of optical signals in the device. The optical device can include a tapered region or long period grating that causes the core mode to spread or couple into the cladding region and, simultaneously, allows the active material to be relatively close to the propagated modes, thus allowing interaction between the active material and the propagating modes.

Modifying birefringence in optical fibers

Growing community of inventors

Summit, NJ, United States of America

Benjamin John Eggleton