Abstract: A source that employs an Erbium-Doped Fiber Amplifier (EDFA) for generating light in an S-band of wavelengths. The EDFA uses a fiber having a core with a core cross section surrounded by a depressed cladding with a depressed cladding cross section and a secondary cladding with a secondary cladding cross section. A pump source is provided for pumping the Erbium contained in the core of the fiber to a high relative inversion D, such that the Erbium exhibits positive gains in the S-band and high gains in a long wavelength band longer than the S-band. The core cross-section, the depressed cladding cross-section, and the refractive indices no, n1, and n2 are selected to produce losses at least comparable to the high gains in the long wavelength band and losses substantially smaller than the positive gains in the S-band.

Abstract: An optical system (10) that couples pump light (30) into a signal fiber (12) of a fiber array laser/amplifier. The system (10) includes a tapered light guide (TLG) (24) optically coupled to the signal fiber (12) so that the signal light propagates into a single-mode core (48) extending through the TLG (24). The TLG (24) includes a diffraction grating aperture (34) through which the pump light (30) is coupled into the TLG (24). An array of diode emitters (28) is positioned adjacent to the diffraction grating aperture (34) so that the pump light (30) is diffracted into the TLG (24). The pump light (30) is reflected off of the interface (40) between the TLG (24) and air. The angle of the pump light (30) as it is reflected off of an interface (40) between the TLG (24) and air decreases so that the pump light (30) is contained within the signal fiber (12).

Abstract: An apparatus and method for making n different types of optical amplifiers on one manufacturing line, n being equal to 2 or more. The method includes providing a supply of at least four functional groups of subunits for each of the circuits which comprise each of the optical amplifiers to be made, where at least one functional group contains at least n different types of sub-units, and where each of the sub-units in three of the functional groups includes a pluggable optical connector half and where each of the sub-units of the fourth of the functional groups includes three pluggable optical connector halves. The method further includes selecting a specific sub-unit from each of the four functional groups and plugging together each of the selected subunits to form an optical amplifier having the desired specification.

Abstract: An optical transmission device which reduces optical noise in an optical transmission system. The optical transmission device includes a core light amplifying unit, and a first buffer light amplifying unit for amplifying a first signal light from a first transmission path and an amplified second signal light from the core light amplifying unit. The first buffer light amplifying unit supplies the core light amplifying unit with the first signal light, and supplies the first transmission path with the amplified second signal light. Also provided is a second buffer light amplifying unit for amplifying a second signal light from a second transmission path and an amplified first signal light from the core light amplifying unit. The second buffer light amplifying unit supplies the core light amplifying unit with the second signal light, and supplies the second transmission path with the amplified first signal light.

Abstract: An optically active fiber (30) is disclosed for making a fiber laser (18) or an amplifier (16). This double-clad structured active fiber (30) has a core (34), doped with an optically excitable ion having a three-level transition. The core (34) has a core refractive index and a core cross-sectional area. An inner cladding (32) surrounds the core (34). The inner cladding (32) has an inner cladding refractive index less than the core refractive index, an inner cladding cross-sectional area between 2 and 25 times greater than that of the core cross-sectional area, and an aspect ratio greater than 1.5:1. An outer cladding (36) surrounds the inner cladding (32) and has an outer cladding refractive index less than the inner cladding refractive index.

Abstract: 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 material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: 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 material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: Provided herein are a planar optical circuit and optical transmission system in which signal light power can be adjusted with respect to signal light and light that is different from the wavelength band of the signal light can be maintained satisfactorily. The planar optical circuit 1 is composed of a filter 10 that can cause loss of variable wavelength dependence to signal light of a signal light wavelength band such that signal light input from a signal light input end 111 is caused to have loss at given wavelength dependent loss by filter 10 and is output from signal light output end 112.

Abstract: An erbium-doped fiber amplifier, a flexible optical circuit and a method for fabricating the flexible optical circuit are described herein. Basically, the erbium-doped amplifier includes a laser diode, a multiplexer and a flexible optical circuit. The flexible optical circuit in one embodiment includes a predetermined length of optical fiber that is placed onto and secured to a partially flexible sheet of material. Several different embodiments of the flexible optical circuit are described herein. In operation, the erbium-doped amplifier receives an optical signal that is coupled by the multiplexer along with a light from the laser diode into the erbium-doped optical fiber which becomes excited by the light from the laser diode and outputs an amplified optical signal.

Abstract: Optical fibers (e.g., fiber lasers and fiber amplifiers), and systems containing such optical fibers are disclosed.

Abstract: Optically pumped rare-earth-doped polarizing fibers exhibit significantly higher gain for one linear polarization state than for the orthogonal state. Such a fiber can be used to construct a single-polarization fiber laser, amplifier, or amplified-spontaneous-emission (ASE) source without the need for additional optical components to obtain stable, linearly polarized operation.

Abstract: The present invention relates to a fluorescent glass capable of being doped with a high concentration of rare earth ions and suitable for optical communication application, and an optical component incorporating it. The fluorescent glass comprises Al2O3 of 15 to 50 mol %; SiO2 of 0 to 80 mol %; an oxide of 5 to 85 mol % in total comprising at least one of B2O3, Ga2O3, Y2O3, Ta2O5, Sb2O3, Nd2O5, La2O3, and Yb2O3; and a rare earth ion. Concentration quenching is more suppressed in this fluorescent glass than in conventional fluorescent glasses, and it is thus feasible for the fluorescent glass to be doped with a high concentration of rare earth ions and to highly efficiently generate fluorescence of wavelengths in the signal wavelength bands generally used in optical communication.

Abstract: A tellurite glass material has a composition of Li2O:TiO2:TeO2, and contains a dopant comprising ions of a rare earth metal. The rare earth ions can be thulium ions, Tm3+, to provide a material offering optical gain at 1470 nm. The properties of the glass make it suitable for the fabrication of high quality optical fibers and planar waveguides, which can in turn be used in optical amplifiers and oscillators. Co-doping the glass with acceptor ions such as holmium ions, Ho3+, improves the population inversion in the rare earth ions and hence enhances the gain.

Abstract: An optical waveguide fiber amplifier comprising a core region comprises at least in part between 1300 wt.ppm and 3600 wt.ppm Er2O3, between 6.0 wt. % to 10.0 wt. % Al2O3 and between 9.0 wt. % and 20.0 wt. % GeO2. The amplifier also comprising an inner clad surrounding the core region and an outer clad surrounding the inner clad. The relative refractive index percentages and radii of the core region, inner clad and outer clad are chosen from the following ranges: the relative refractive index percent of the core segment within the range of from about 0.5% to about 2.0%; the relative refractive index percent of the inner clad within the range of from about 0.0% to about 0.4%; the outer radius of the core region within the range of from about 0.7 &mgr;m to about 1.5 &mgr;m; and, the outer radius of the inner clad within the range of from about 4.3 &mgr;m to about 18.8 &mgr;m.

Abstract: An optical amplifier and a laser generator based on the fiber side-polished technology having a high pumping efficiency, a low noise figure and a small footprint are provided in this application. The optical amplifier and the laser, which have a very long effective interaction length in conjunction with highly doped Erbium glass attached to its surface and an addition of a slanted fiber grating inscribed in the guiding core at the polished region can spatially separate the signal and pump power to simultaneously improve the pumping efficiency and optimize the penetrated depth of the signal evanescent-field. The spontaneous emission is kept from being amplified and therefore a high quality amplified signal is produced.

Abstract: A source of optical pulses, comprises an optical source operable to generate ultrashort optical pulses at a first wavelength; and an optical fiber amplifier comprising an optical fiber having a core containing a dopant to provide optical gain at the first wavelength and anomalous dispersion over a wavelength range including the first wavelength and a second wavelength. The optical fiber receives the ultrashort optical pulses, amplifies the ultrashort optical pulses, and alters the wavelength of the ultrashort optical pulses to at least the second wavelength by the soliton-self-frequency shifting effect. Microstructured and/or tapered fibers can be used to provide the required dispersion characteristics. Pulses can be generated in one of three spectral regimes—monocolor solitons, multicolor solitons and continuous broadband spectra by adjusting the energy of the optical pulses, and tunability can be achieved by varying the power of pump light provided to the amplifier.

Abstract: A waveguide amplifier having an input coupler, a gain stage, and a pump reflector monolithically integrated on a common substrate. The input coupler multiplexes pump light with signal light, the active region of the gain stage absorbs some of the pump light, amplifies the signal light, and passes the unabsorbed pump light and/or any unabsorbed amplified spontaneous emissions (ASE) to the reflector. The reflector reflects the unabsorbed pump light and/or any unabsorbed amplified spontaneous emissions (ASE) back into the active region of the gain stage to improve the efficiency of the waveguide amplifier.

Abstract: 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 efficiency. The optical fiber amplifier includes a rare earth doped fiber. Pump light from a pump light source is introduced into one end of the rare earth doped fiber by way of a first optical coupler, and residual pump light originating from the pump light and arriving at the other end of the rare earth doped fiber is applied to the other rare earth doped fiber amplifier or the loss compensation of a dispersion compensating fiber by Raman amplification.

Abstract: A supervisory system and supervisory method of an optical amplifier repeater are proposed that can implement operation supervision taking account of the characteristics of individual supervisory targets of the optical amplifier repeater, thereby achieving higher reliability.

Abstract: This invention relates to an optical amplification fiber having a structure capable of exhibiting an excellent amplification characteristics, and the like. In the optical amplification fiber, the ratio (&agr;P/&agr;S) of an unsaturated absorption peak value &agr;P in a pumping light wavelength band of 0.98 &mgr;m to an unsaturated absorption peak value &agr;S in a signal wavelength band of 1.55 &mgr;m is 0.8 or more and, more preferably, 0.9 or more.

Abstract: An L band optical amplifier in disclosed. The optical amplifier includes a signal line which has an input, an output disposed optically downstream of the input, and an amplifying gain medium optically disposed between the input and the output. The optical amplifier further includes a laser optically connected to the first amplifying gain medium and a C band seed pump optically connected to the signal line for directing C band light into the amplifying gain medium.

Abstract: The amplifying optical fiber (1) comprises a single-mode core (10) and a multimode core (20) surrounding the single-mode core, the multimode core containing a doped layer referred to as a “doped ring” (21) and having a certain concentration of active rare earth ions (6) to perform amplification by active rare earth ions on at least one optical signal for injection into the amplifying fiber. The fiber is dimensioned so that the product of its length multiplied by its Raman efficiency is greater than or equal to 0.5 W−1. In addition, the fiber presents absorption defined by an absorption coefficient expressed in dB/m, which absorption presents, at a certain wavelength, a maximum value referred to as the “absorption maximum”, the fiber presents accumulated absorption, corresponding to the product of its length multiplied by the absorption maximum, that is greater than or equal to 100 dB.

Abstract: A backlight for a liquid crystal display (LCD) employing light recycling. In one embodiment the backlight includes a light guide fabricated from a substantially non-absorptive material and a reflective layer fabricated from a highly reflective material. In another embodiment the backlight includes a light source, a bundle of optical fibers, and a reflective layer fabricated from a highly reflective material, wherein the bundle of optical fibers is configured to receive light from the light source and distribute it to the reflective layer.

Abstract: An optical threshold device including an optical loop having first and second terminals aid including at least one non-linear optical element and at least one optical attenuator; and an optical coupler able to couple a first portion of an input signal to the first terminal and a second portion of the input signal to the second terminal, wherein the optical loop is able to produce a first return signal at the second terminal and a second return signal at the first terminal, and wherein the optical coupler is able to combine the first and second return signals into an output signal.

Abstract: A simple and flexible WDM laser source is disclosed using a loop erbium-doped fiber amplifier (LEDFA) configuration. The loop serves as a mirror and as an amplification medium. The laser cavity was made from the loop mirror and a set of fiber Bragg gratings (FBGs) which select the proper lasing wavelengths. The FBGs can be placed either in parallel or in series at the output of the loop configuration. Optical attenuators are placed in front of the FBG to control the flatness of the laser source output and determine the required lasing condition for each wavelength to avoid competition of the different lasing wavelengths. This configuration is flexible for adding any number of wavelengths as long as enough amplified spontaneous emission (ASE) is generated in the loop. Signal to noise ratio as high as 55-dB can be achieved.

Abstract: 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 material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: An L band optical amplifier in disclosed. The amplifier includes a signal line for transmitting a signal light in a first direction. The signal line includes an input, an output disposed optically downstream of the input, and a first amplifying gain medium optically disposed between the input and the output. A first laser is optically aligned with the first amplifying gain medium to transmit a first pump light to the first amplifying gain medium toward the output. A first reflector is disposed along the signal line between the first amplifying gain medium and the output to reflect a first bandwidth of light from the first amplifying gain medium back into the first amplifying gain medium. A second laser is optically aligned with the first amplifying gain medium to transmit a second pump light to the first amplifying gain medium toward the input.

Abstract: This invention relates to the following four structures for attaining a flat gain spectrum over a wide wavelength region. The first structure relates to a Raman amplifier where a tellurite fiber is pumped with two wavelengths having a predetermined difference. The second structure relates to a Raman amplifier or an optical communication system employing a tellurite fiber and a silica fiber. The third structure relates to an optical fiber amplifier employing an Erbium-doped tellurite fiber of which Erbium concentration is low. The fourth structure relates to an optical fiber amplifier employing a rare-earth doped fiber such as the Erbium-doped fiber and a tellurite fiber.

Abstract: The present invention relates to an optical fiber transmission line and the like comprising a structure for enabling repeating sections to become further longer. The optical fiber transmission line comprises first and second optical fibers successively disposed along the traveling direction of signal light, and an optical multiplexer for supplying Raman amplification pumping light to one of the first and second optical fibers. The first and second optical fibers are optically connected to each other. The second optical fiber has an effective area smaller than that of the first optical fiber, and a chromatic dispersion and a length which are different from those of the first optical fiber. In particular, the respective lengths of the first and second optical fibers are appropriately regulated so as to effectively suppress nonlinear phenomena other than Raman amplification.

Abstract: An optical fiber for optical amplification used for 1.58 &mgr;m band signal light amplification, at least a core region thereof being doped with Er has a core region at least a part thereof made of silica glass co-doped with Ge and Al together with Er, and Er average atomic concentration in the core region is from 1000 wt-ppm to 3000 wt-ppm inclusive, and cutoff wavelength is from 1.3 &mgr;m to 1.5 &mgr;m inclusive.

Abstract: An optical amplifier, or optical repeater, for amplifying wavelength division multiplexed (WDM) light A first demultiplexer demultiplexes the WDM light into first and second lights corresponding to different wavelengths in the WDM light. First and second optical amplifiers amplify the first and second lights, respectively. A first multiplexer multiplexes the amplified first and second lights into a multiplexed light. A dispersion compensator compensates for dispersion in the multiplexed light. A second demultiplexer demultiplexes the dispersion compensated, multiplexed light into the first and second lights. Third and fourth optical amplifiers amplify the demultiplexed first and second lights, respectively. A second multiplexer multiplexes the amplified first and second lights from the third and fourth optical amplifiers into a WDM light. The optical amplifier can be configured so that the first and second lights travel through the dispersion compensator in opposite directions.

Abstract: A method of producing a short-pass fiber by drawing a preform for a depressed cladding fiber at a predetermined drawing ratio. The preform has a core of refractive index no, a depressed cladding surrounding the core and having a refractive index n1, and a secondary cladding surrounding the depressed cladding and having a refractive index n2. The core has a core cross-section and the depressed cladding has a depressed cladding cross-section that is larger than the core cross-section. The drawing ratio is determined based on the parameters of the preform measured along the axis of the preform and based on a desired minimum fundamental mode cutoff wavelength &lgr;m. The final core cross-section defines a fundamental mode cutoff wavelength &lgr;c such that &lgr;c≧&lgr;m along the axis. Then the preform is pulled by the thus-determined drawing ratio to produce the short-pass fiber. In some embodiments a test section of the fiber is pulled first before pulling the short pass fiber.

Abstract: An erbium-doped (Er-doped) superfluorescent fiber source (SFS) has an enhanced mean wavelength stability. A method determines an estimated mean wavelength of a SFS. The method includes providing an Er-doped SFS having an actual mean wavelength. The method further includes configuring the SFS such that the actual mean wavelength has a dependence on the temperature of the EDF. The method further includes obtaining the dependence of the actual mean wavelength on the temperature of the EDF. The method further includes measuring the temperature of the EDF. The method further includes calculating the estimated mean wavelength using the measured temperature of the EDF and the dependence of the actual mean wavelength on the temperature of the EDF.

Abstract: An optical fiber transmission line including first, second and third optical fibers connected together so that light travels through the transmission line from the first optical fiber, then through the second optical fiber and then through the third optical fiber. The first, second and third optical fibers have first, second and third characteristic values, respectively. The second characteristic value is larger than the first characteristic value and the third characteristic value. The characteristic value of a respective optical fiber being a nonlinear refractive index of the optical fiber divided by an effective cross section of the optical fiber. Pump light is supplied to the transmission line so that Raman amplification occurs in the transmission line as an optical signal travels through the transmission line.

Abstract: A fiber optic isolator device is used by fiber optic systems operating at more than one wavelength. The device may be inserted anywhere within the fiber network. The fiber optic device permits the separation of the wavelengths so that an optical isolator module can isolate a first wavelength without significantly affecting the second wavelength. This device is useful isolating a communications signal at 1.55 &mgr;m while avoiding significant losses for an optical time domain reflectometry signal, for example at 1.3 &mgr;m.

Abstract: An optical amplifier includes an optical amplifying medium, an excitation source which excites the optical amplifying medium, and at least one of a first monitor for monitoring an amplified multiplexed light from the optical amplifying medium and a second monitor for monitoring a multiplexed light input to the optical amplifying medium. An operation amount of the excitation source for the optical amplifying medium is controlled using a monitoring result output from at least one of said first and second monitors.

Abstract: A compact, high-power, low-cost broadband ASE source is achieved by multi-mode pumping a highly doped multi-component glass fiber in standard ASE source configurations. The multi-mode pump is coupled into and propagates in the fiber cladding exciting the rare-earth dopant ions (Er,Yb) in the fiber core. The multi-component glass includes a network former selected from either phosphate (P2O5) or tellurite (TeO2) and is doped with at least 0.25 weight percent rare-earth dopants. The high concentrations of dopants supported by these glasses absorbs the multi-mode pump in a short length, less than 100 cm, and provides high saturated output powers.

Abstract: An optical fiber amplifier features an optical amplifying section for amplifying an inputted optical signal. A sampling section is provided for shunting part of the optical signal amplified by the optical amplifying section and detecting a first test light belonging to a short wavelength band and a second test light belonging to a long wavelength band. An input power control circuit serves to compare respective powers of the first and second test lights and then outputs a control signal for controlling an input power of the optical signal inputted to the optical amplifying section according to the power differential of the first and second test lights. An output power control circuit derives an output power of the optical amplifying section from the power of the optical signal shunted at the sampling section and also controls the optical amplifying section so that the output power of the optical amplifying section attains a predetermined value.

Abstract: Disclosed is an L-band optical amplifier for amplifying optical signals with the wavelength band of the L-band. The L-band optical amplifier comprises an optical-amplifying section for emitting spontaneous emission and for amplifying the optical signals by pumping of the spontaneous emission, a mirror for reflecting the optical signals amplified by the optical-amplifying section to re-enter back to the optical-amplifying section, and a feedback loop connected with both terminals of the optical-amplifying section for causing spontaneous emission emitted from the optical-amplifying section to be fed back to the optical-amplifying section.

Abstract: Multi-wavelength light is inputted to an erbium-doped fiber as an optical amplification medium. Pump light is supplied to this erbium-doped fiber. When a transition from a state signal light on the short wavelength area in the multi-wavelength is input in the erbium-doped fiber to a state the signal light is not input, the output power of signal light on the long wavelength area in the multi-wavelength light can vary. The wavelength of pump light is selected in such a way that the output power of the signal light on the long wavelength area can not be negative when the power varies.

Abstract: The optical transmission system in accordance with the present invention is an optical transmission system in which an optical fiber transmission line is laid between a transmitting station and a receiving station, first and second optical couplers are provided on the optical fiber transmission line, a first Raman amplification pumping light source is connected to the first optical coupler, a second Raman amplification pumping light source is connected to the second optical coupler, the optical fiber transmission line Raman-amplifies signal light in S band when Raman amplification pumping light is supplied thereto while transmitting the signal light, and the optical fiber transmission line has a zero-dispersion wavelength of 1350 nm to 1440 nm and a cable cutoff wavelength of less than 1368 nm.

Abstract: Featured is a high power, broadband superfluorescent source with very low relative intensity noise (RIN) including a seed source, a modulator operably coupled to the seed source and a polarization maintaining (PM) amplifier operably coupled to the modulator. The output of the seed source is processed in the modulator so the modulator outputs a polarized optical output to the PM amplifier. The PM amplifier amplifies the modulated, polarized optical output so as to provide an amplified polarized optical output therefrom. Also featured is a feedback circuit operably coupled to the PM amplifier to control the transmission of the modulator so as to minimize the amplitude fluctuations in the output signal. Such a source is advantageous in high precision fiber optical rotation sensors and multiplexed strain sensing arrays.

Abstract: A detector system for a fiber optic component is insensitive to stray light. Specifically, the invention comprises a detector chip, which converts received light into an electric signal. A baffle substrate is positioned over the detector chip. This baffle substrate has a transmission port through which an optical signal is transmitted to the detector chip. As a result, light that is not directed to be transmitted through the port is blocked by the baffle substrate. In this way, it rejects stray light that may be present in the hermetic package. A detector substrate is provided on which the detector chip is mounted. This detector substrate preferably comprises electrical traces to which the detector chip is electrically connected. The detector substrate can further comprise bond pads for wire bonding to make electrical connections to the electrical traces.

Abstract: A controller for controlling a transceiver having a laser transmitter and a photodiode receiver. The controller includes memory for storing information related to the transceiver, and analog to digital conversion circuitry for receiving a plurality of analog signals from the laser transmitter and photodiode receiver, converting the received analog signals into digital values, and storing the digital values in predefined locations within the memory. Comparison logic compares one or more of these digital values with limit values, generates flag values based on the comparisons, and stores the flag values in predefined locations within the memory. Control circuitry in the controller controls the operation of the laser transmitter in accordance with one or more values stored in the memory. A serial interface is provided to enable a host device to read from and write to locations within the memory.

Abstract: An optical fiber includes a core for guiding light of a specified range of wavelengths therethrough, each wavelength in the specified range of wavelengths traveling through the core at a particular group velocity and the light potentially producing a nonlinear optical effect. The optical fiber also includes a cladding formed around the core for substantially containing the light within the core. The optical fiber further includes a predetermined amount of at least one dopant uniformly dispersed throughout the core such that no two distinct wavelengths in the specified range of wavelengths travel through the core at the same, particular group velocity, thereby causing the nonlinear optical effect to be suppressed.

Abstract: An optical waveguide for use in amplifying light signals with an integrated gain equalization filter. The optical waveguide includes a gain section for amplifying light signals. The optical waveguide further includes an equalization filter to improve the uniformity of optical gain over a wavelength range for which the gain section is intended to provide amplification.

Abstract: An optical fiber amplifier is considered comprising a mono-mode core, a first cladding around said core and at least a further cladding around said first cladding while said first cladding includes a ring shaped active region doped with rare earth material surrounding said mono-mode core. Advantageously, the first cladding is designed with a radial refractive index following an almost continuous decreasing function for increasing radius. The use of a continuously decreasing refractive index for the cladding at the outer border of the ring shaped active medium optimize the efficiency of the coupling between the core and the cladding.

Abstract: An optical amplifier utilizes two or more doped fiber segments or portions to achieve a lower noise figure and a higher saturation power than would be possible using any one of the doped fiber segments. Each doped fiber portion may be considered to be a doped fiber optical amplifier, and has a different doping level than each of the other doped fiber portions. Each such doped fiber portion has distinct amplitude gain and noise characteristics relative to each of the other doped fiber potions. The two or more doped fiber portions are coupled to each other in series and most often in a predefined order based on their relative amplitude gain, noise and saturation power characteristics.

Abstract: According to an exemplary embodiment of the present invention, an optical waveguide and method of use includes a grating which has a grating parameter that is adapted for dynamically variable non-uniform alteration. The non-uniform alteration of the grating parameter results in the introduction of a predetermined amount of chromatic dispersion and dispersion slope into an optical signal traversing the waveguide. According to another exemplary embodiment of the present invention, an optical apparatus and method of use includes a plurality of optical waveguides each of which have an optical grating and at least one of the waveguide gratings has a grating parameter that is adapted for dynamically variable non-uniform alteration. The optical apparatus further includes a device, which dynamically varies the grating parameters of each of the waveguides to selectively introduce chromatic dispersion and dispersion slope into an optical signal traversing the apparatus.

Abstract: Disclosed is a multi-lambda source for outputting an optical signal having a plurality of channels, the multi-lambda source comprising an optical fiber amplifier, having a back and front end, for amplifying an optical signal received from the back end and outputting ASE light to the back end, a reflector coupled to the back end of the optical fiber amplifier for reflecting a received optical signal, and a comb filter arranged between the optical fiber amplifier and the reflector and having a pass band of wavelengths for filtering the ASE light and generating the optical signal of the channels according to a transmission spectrum of the filtered ASE light.