Match Document Document Title
6496301 Helical fiber amplifier  
A multi-mode gain fiber is provided which affords substantial improvements in the maximum pulse energy, peak power handling capabilities, average output power, and/or pumping efficiency of fiber...
6496300 Optical amplifier  
An optical amplifier of a wavelength-division multiplexing transmission system that includes a pre-stage optical amplifying unit and a post stage optical amplifying unit. The pre-stage optical...
6493133 System and method for increasing capacity of undersea cables  
A method of increasing usable bandwidth on a long-haul cable system having at least one optical fiber, the method comprising the steps of: (a) effecting counter-propagating first and second signals...
6490079 Device for suppressing transient effect of optical fiber amplifier in WDM system  
A device for suppressing the transient effect of an optical fiber amplifier in a WDM system includes an input sensor which converts an input optical signal to an electrical signal; a transient...
6487352 Electrical detector for adaptive control of chromatic dispersion in optical systems  
An optical device for detecting chromatic dispersion is described. The optical device includes a receiver, which converts an optical signal into an electrical signal having a plurality of frequency...
6487006 Simultaneous single mode and multi-mode propagation of signals in a double clad optical fiber  
An optical amplifier having a suitable length of Er/Yb co-doped double clad optical fiber is used to amplify an input optical signal. The inner clad of the double clad optical fiber supports the...
6487005 Optical fiber transmission system with chromatic dispersion compensation  
A long-distance optical transmission system comprising pulse emitter and receiver means ( 1, 2 ) and an optical line ( 3 ) which extends between said emitter and receiver means ( 1, 2 ) and which...
6483637 System and method for per-band optical amplification  
A method and apparatus for amplifying an optical signal is provided. In accordance with one example embodiment of the invention, the optical amplification system includes an optical signal...
6483636 Optical amplifier  
An optical amplifier to reduce signal loss by reducing crosstalk, and method therefor. A demultiplexer isolates an optical signal into a first wavelength band and a second wavelength band. The...
6483635 Apparatus for light amplification  
A system for reducing reflection of an optical system can reduce or eliminate reflection at facets of a semiconductor gain medium and can suppress natural longitudinal modes produced within the...
6483632 Multistage optical amplifier with gain flattening  
A variable gain optical amplifier, in which homogeneous gain broadening is dominant, has first and second fixed gain rare-earth doped optical waveguide amplifiers ( 21, 23 ) optically in series...
6483631 Optical amplifier spectral tilt controllers  
Spectral tilt controllers are provided for optical amplifiers and other optical network equipment used in fiber-optic communications links in fiber-optic networks. The tilt controllers may be used...
6483630 OPTICAL AMPLIFIER, METHOD OF CONTROLLING THE OUTPUT LIGHT FROM THE OPTICAL AMPLIFIER, OPTICAL TRANSMISSION SYSTEM AND METHOD OF CONTROLLING AN OPTICAL TRANSMISSION PATH CROSS REFERENCE TO RELATED APPLICATION  
A method of controlling an output of an optical amplifier which amplifies a multiplexed light ray propagated through a transmission path in an optical transmission system and which includes a probe...
6480329 Multi-wavelength light amplifier  
A multi-wavelength light amplifier includes a first-stage light amplifier which has a first light amplifying optical fiber amplifying a light input, a second-stage light amplifier which has a...
6477297 Reduction of bend loss through constraint of optical fiber parameters  
A method of assembling an optical system includes the steps of: (i) selecting, from a plurality of optical fibers characterized by a common nominal cut-off wavelength λ cn and an actual cut-off...
6476961 Optical amplifier systems with transient control  
Optical amplifier equipment for operation in fiber-optic communications networks is provided. The optical amplifier equipment may include one or more gain, stages based on rare-earth-doped fiber or...
6473225 Light amplifier device  
In order to be able to use a semiconductor light amplifier of conventional type and operating under gain saturation conditions while nevertheless providing constant gain for an optical signal to be...
6469826 Optical amplifier  
In the optical amplifier an optical divider based on long wavelength (or short wavelength) transmission type dielectric multi-layer filter divides input signal light according to wavelengths, and...
6469825 Method of amplifying optical signals using erbium-doped materials with extremely broad bandwidths  
In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous yttrium aluminum oxide...
6466712 Optical transmission link incorporating highpass optical filtering  
An optical fiber transmission link with reduced channel depletion due to stimulated Raman scattering is formed by including a high pass optical filter in the transmission fiber. The filter may...
6466364 Gain flattening with nonlinear sagnac amplifiers  
An apparatus and a method provide gain flattening in communications systems wherein a large number of optical signals at different wavelengths must be amplified while maintaining signal power...
6466362 Hybrid amplifier and control method herefor that minimizes a noise figure for particular span loss  
A hybrid amplifier reduces the noise generated by the hybrid amplifier. The hybrid amplifier includes a rare-earth doped fiber amplifier such as an EDFA (erbium-doped fiber amp), a Raman amplifier,...
6466344 Optical switch, optical amplifier and optical power controller as well as optical add-drop multiplexer  
The first present invention provides an optical switch including the following elements. At least a plurality of optical transmission lines are provided for transmission of optical signals. Each of...
6462878 Double chirped mirror  
The invention is a double chirped mirror and a method of constructing a double chirped mirror for a frequency range of electromagnetic radiation, comprising specifying a design including a...
6462863 System and method for resolving polarization mode dispersion in optical fibers  
A system and method for resolving polarization mode dispersion (PMD) in a span of optical fiber is described. The method involves three main stages: (1) launch two co-polarized optical signals to...
6462862 Optical fiber amplifier and dispersion compensating fiber module for optical fiber amplifier  
The invention provides an optical fiber amplifier which assures stable operation of a pump light source and efficiently makes use of residual pump power to achieve improvement in conversion...
6462861 Optical amplifying apparatus and optical communication system  
The present invention aims at providing an optical amplifying apparatus constituted by combining Raman amplifiers, in which deterioration of a signal/noise ratio of output light is prevented to...
6459527 Optical amplifier apparatus and control method thereof, and optical transmission system using optical amplifier apparatus  
A control method of an optical amplifier apparatus for compensating a gain characteristic of an optical amplifying medium. The control method includes providing an active gain characteristic...
6459526 L band amplifier with distributed filtering  
An L-band optical amplifier has a rare earth doped gain medium including a filter distributed over a finite physical portion of the gain medium. The filter is distributed over between about 25% to...
6456427 Systems and methods for reducing a signal spectrum tilt  
Methods and systems for reducing a first tilt of a spectrum of light transmitted via an optical fiber are provided. To reduce the first tilt, an amplifier, such as an erbium doped fiber amplifier,...
6456426 Raman amplifiers with modulated pumps  
Optical amplifiers are provided in which optical gain is produced by Raman pumping fiber. The Raman-pumped fiber may be a span of transmission fiber or a coil of fiber in a discrete amplifier....
6456425 Method and apparatus to perform lumped raman amplification  
A method and apparatus to amplify an optical signal is described. A first filter splits an optical signal into a first and second parts. A first raman amplifier amplifies the first part. A second...
6452722 Optical amplifier with automatic level control and automatic gain control  
Regulated optical amplifiers for wavelength-division multiplex signal transmission that include a first control device for regulating the gain and a second, dominating control device having a...
6452719 Optical communication system and optical amplifier  
An optical communication system having a transmitting station for outputting WDM (wavelength-division multiplexing) signal light, an optical fiber transmission line, a receiving station, and an...
6452718 WDM-channel equalizer  
The present invention relates to an arrangement and a method relating to optical channel equalizers. The channel equalizer includes at least one Q-port direction-dependent router ( 40 ), where...
6452717 Fiber optic amplifier  
The present invention relates to a fiber optic amplifier comprising a structure enabling favorable signal amplification characteristics to be maintained even in an environment exposed to radiation....
6449085 Optical direct amplifier and control method thereof  
An optical direct amplifier includes an O/E converter for converting a branched output light into an electric signal, a frequency variable filter for detecting a modulated frequency specific to a...
6449070 Optical transmission device and wavelength-multiplexed optical transmission system  
An optical transmission device that can be applied to a wavelength-multiplexed optical transmission system includes a first part creating a supervisory control signal to be transmitted in optical...
6445493 Balanced gain flattening filters  
Compound gain flattening filters of optical amplification include a series of filter components with spectral responses that are combined to approach a target loss spectrum. Small variations in the...
6441955 Light wavelength-multiplexing systems  
A wavelength-division multiplexing optical communication system for wavelength-division multiplexing a plurality of optical signals having different wavelengths and transmitting a...
6441953 L band multistage amplifier with improved noise figure  
A multi-stage optical fiber amplifier comprises a first gain stage amplifying and optical signal; a pumping source coupled to the first gain stage, a second gain stage coupled to the first gain to...
6441952 Apparatus and method for channel monitoring in a hybrid distributed Raman/EDFA optical amplifier  
The present invention provides a hybrid Raman/EDFA optical amplifier that utilizes a first optical detector that generates a first electrical or electronic signal that is proportional the combined...
6437908 Optical amplifying device  
An optical brancher 110 branches an input optical signal into two. An optical detector 120 converts one optical signal branched by t e optical brancher 110 into an electrical signal. A first...
6437906 All-optical gain controlled L-band EDFA structure with reduced four-wave mixing cross-talk  
An approach for minimizing four-wave mixing (FWM) cross-talk (XT) in a WDM (wavelength division multiplexing) optical communication system is disclosed. An Erbium doped Fiber Amplifier (EDFA)...
6433925 Optical fiber amplifier and optical transmission system using the same  
A variable attenuator is inserted into an optical input part and a feedback control is performed so that an optical input to an amplifying optical fiber becomes constant. Further, a control for...
6433924 Wavelength-selective optical amplifier  
A wavelength-selective filter, such as a narrow bandpass filter, is used to filter both the input and output of an optical amplifier. The selected channel is amplified and can be re-combined with...
6433923 Optical transmission path having sections which overcompensate for dispersion occurring in the sections  
An optical communication system which includes a transmission path through which a light is transmitted to a specific point, such as to a receiver. The transmission path includes a plurality of...
6433922 Apparatus and method for a self adjusting Raman amplifier  
This invention describes an apparatus and method for a self adjusting Raman amplifier for fiber optic transmission lines incorporating a line diagnostic mechanism in order to calculate, control and...
6433920 Raman-based utility optical amplifier  
An optical amplifier with a flattened wideband response is obtained by coupling counter-propagating pumping energy into an optical waveguide to cause Raman amplification in the optical waveguide,...
6429964 High power, multiple-tap co-doped optical amplifier  
A high power optical amplifier with a multiple-tap output includes a preamplifier stage (such as an EDFA), followed by a power amplifier comprises a concatenated set of co-doped optical amplifier...