Abstract: A laser therapeutic apparatus includes a laser and a therapeutic optical fiber. The therapeutic optical fiber is configured for being implanted into a body of a patient during surgery to perform a repair treatment on a spinal cord site to-be-treated by irradiation and then being removed from the body of the patient after the surgery. The therapeutic optical fiber includes N number of laser fibers, N?1 number of optical fiber connection components, an optical fiber guiding structure, and an optical fiber controller; the N number of laser fibers are coupled with one another by the N?1 number of optical fiber connection components to form a cascaded optical fiber structure, an end of the cascaded optical fiber structure is coupled to the optical fiber guiding structure, and another end of the cascaded optical fiber structure is coupled to the optical fiber controller.

Abstract: An optical amplifier (1), and a related optical amplification method, comprising an optical path (2) having an input end (3) and an output end (4), a first erbium doped optical fiber (5) placed along the optical path, a first gain flatting filter (6) placed along the optical path downstream the first erbium doped optical fiber, a second erbium doped optical fiber (7) placed along the optical path downstream the first gain flatting filter, a second gain flatting filter (8) placed along the optical path downstream the second erbium doped optical fiber, a third erbium doped optical fiber (9) placed along the optical path downstream the second gain flatting filter, and an optical pump (10) optically coupled to the optical path so as to optically pump at least the first and the third erbium doped optical fiber.

Abstract: Various embodiments described herein comprise a laser and/or an amplifier system including a doped gain fiber having ytterbium ions in a phosphosilicate glass. Various embodiments described herein increase pump absorption to at least about 1000 dB/m-9000 dB/m. The use of these gain fibers provide for increased peak-powers and/or pulse energies. The various embodiments of the doped gain fiber having ytterbium ions in a phosphosilicate glass exhibit reduced photo-darkening levels compared to photo-darkening levels obtainable with equivalent doping levels of an ytterbium doped silica fiber.

Abstract: A light generation and amplification system includes a length of laser-active filter fiber having a refractive index profile that suppresses unwanted Stokes orders at wavelengths longer than a target wavelength and that has normal dispersion over its operating wavelength. A nested series of reflectors is provided at the fiber's input and output ends, and are configured to provide a nested series of Raman cavities, separated in wavelength by approximately the respective Stokes shifts. The first cavity in the series is a combined cavity that provides laser oscillation due to a combination of ionic gain and feedback at a selected first wavelength and that provides Raman gain to light at the first Stokes shift of the first wavelength when light at the first wavelength has an energy exceeding a Raman scattering threshold. The Raman cavities provide a stepwise transition between the first wavelength and the target wavelength.

Abstract: The present invention has an object to provide an optical amplifier capable of realizing a good response characteristic in a wide frequency band, even when a population inversion state is formed by a pumping light supplied to an optical amplification medium and an ASE light generated in the optical amplification medium. To this end, in the optical amplifier according to the present invention, a delayed phase matching fiber in which a first fiber whose response speed is relatively low is arranged on the input side and a second fiber whose response speed is relatively high is arranged on the output side, is used as the optical amplification medium doped with a rare-earth element.

Abstract: It is an object of the present invention to provide an optical amplifier using optical amplification mediums each doped with a rare earth element for increasing amplification efficiency of signal light in S-band and the like. To this end, the optical amplifier is constituted such that, when performing optical amplification for S-band and the like in which a center wavelength of a gain peak in the optical amplification medium is located at an outside of a signal band, a gain coefficient of when a pumping condition of the optical amplification medium is maximum is set so that a parameter ? obtained by dividing a minimum value of the gain coefficient in the signal band by a maximum value of the gain coefficient outside of the signal band becomes a previously set value or more, wherein, for example, the parameter ? can be increased by controlling a temperature of each of a plurality of EDFs between which gain equalizers are disposed.

Abstract: An apparatus and that provide an optical-fiber amplifier having at least one erbium-doped fiber section and an optical pump coupled to the erbium-doped fiber section, wherein the apparatus is operable to amplify signal pulses to high energy in the erbium-doped fiber section, the pulses having a wavelength in the range of about 1565 nm to about 1630 nm. In some embodiments, the amplifying fiber is ytterbium free.

Abstract: An optical fiber amplifier apparatus and optical signal amplification method are provided. In one example, the amplifier apparatus comprises an optical combiner that is configured to receive an input optical signal to be amplified and a pump light beam. The optical combiner combines for output the input optical signal and the pump light beam. A first cladding pumped optical fiber in which Erbium is the only optically active dopant is coupled to the optical combiner to receive the pump light beam and the input optical signal. The first cladding pumped optical fiber pre-amplifies the input optical signal and passes the pre-amplified input optical signal and power of the pump light beam not absorbed by the first cladding pumped optical fiber. A second cladding pumped optical fiber is provided that is coupled to the first cladding pumped optical fiber. Erbium and Ytterbium are optically active dopants in the second cladding pumped optical fiber.

Abstract: A method of producing higher power optical energy with an optical fiber can include providing a length of optical fiber having a core constructed so as to support more than one mode at a selected wavelength, the length of optical fiber comprising an active material for providing optical gain at the selected wavelength responsive to optical pumping, said optical gain being provided to the optical energy while propagating in at least one higher order mode of the core; providing a length of output optical fiber having a core; and providing for optical communication between the length of optical fiber and the core of the length of output optical fiber wherein the optical energy from the core of the length of optical fiber that experiences optical gain while propagating in at least one of the at least one higher order modes is communicated to the fundamental mode of the core of the length of output optical fiber.

Abstract: A laser device including: a first amplifying medium capable of emitting a first output laser beam at the output wavelength ?s; and a second amplifying medium capable of emitting a second laser beam of intermediate wavelength ?i and capable of being pumped at a pump wavelength ?p such that ?i is included between ?p and ?s; wherein a single laser cavity containing said first and second amplifying media, this cavity being closed by two mirrors with maximum reflection at the wavelength ?i, and in that there are two distinct laser wavelengths ?i and ?s which take place in said cavity.

Abstract: According to an optical surge suppressive type optical amplifier in the present invention, for a WDM optical amplifier having a multi-stages amplification configuration in which a plurality of optical amplifying means is connected in series, an optical amplifying medium capable of causing a homogeneous up-conversion (HUC) phenomenon is applied to the optical amplifying means on the signal light output side, so that an optical surge is suppressed utilizing the degradation of gain efficiency by the HUC caused at the time when the input power is decreased. Further, for a one wave optical amplifier, an optical amplifying medium capable of causing a pair induced quenching (PIQ) phenomenon is applied to the optical amplifying means on the signal light input side, so that the optical surge is suppressed utilizing the degradation of output power efficiency by the PIQ caused at the time when the input power is increased.

Abstract: Disclosed is a method of doping an oxide. The example method includes forming at least one of an AlGaAs oxide or an InAlP oxide on a GaAs substrate, and incorporating Erbium into the at least one AlGaAs oxide or InAlP oxide via ion implantation to form an Erbium-doped oxide layer. The example method also includes annealing the substrate and the at least one AlGaAs oxide or InAlP oxide.

Abstract: An doped fiber optical amplifier featuring an optical component having first wavelength division multiplexer, an isolator and a second wavelength division multiplexer is described. The isolator supports the propagation of optical signals within a predetermined signal wavelength range in one direction. Pump signals having a wavelength within a pump wavelength range are diverted by the wavelength division multiplexers to inhibit coupling of the pump signals with the isolator. The optical amplifier supports the use of relatively high-powered optical pump lasers. The optical component is optically disposed between different lengths of doped fiber and serves to reduce optical noise within the amplifier.

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: An optical amplifier 1 is constructed using an amplification optical waveguide in which a first amplification optical fiber 10 and a second amplification optical fiber 20 are connected in series. A P/Al-codoped EDF 10 excellent in noise characteristics is applied to the upstream first amplification optical fiber 10, and an EDF 20 such as an Al-doped EDF or the like is applied to the downstream second amplification optical fiber 20. This realizes the optical amplifier 1, and the optical transmission system using it, capable of amplifying the signal light in the signal light wavelength band of not less than the wavelength of 1570 nm including the L-band wavelength band of wavelengths from 1570 to 1600 nm, with good gain characteristics and achieving the improvement in the noise characteristics.

Abstract: The present invention is directed to guided wave systems, beam transport and waveguide techniques. The invention may comprise passive or active, hollow and dielectric core self-imaging mode wave guide systems, beam amplifiers (10, 40), laser resonators (70), beam transports, and waveguides. Embodiments may include rectangular cross-section waveguides, and preferably maintaining spatial profile of an input beam, such as a Gaussian beam, through the self-imaging period of the waveguide while unique new capabilities to mitigate non-linear distortions that corrupt spatial, spectral and temporal coherence and polarization. Additional aspects may include, for example, transport, amplification, phase/frequency control or modulation, deflection, conversion, synthetic aperture, distributed aperture, beam forming, beam steering, beam combining, power sampling, power combining and power splitting, among other features.

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 optical waveguide amplifier fiber comprises a core region at least in part comprises Er2O3, Al2O3, GeO2 and Ga2O3. The amplifier fiber also comprises 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 1.2%; the relative refractive index percent of the inner clad within the range of from about 0.0% to about 0.3%; the outer radius of the core region within the range of from about 2.0 &mgr;m to about 5.0 &mgr;m; and, the outer radius of the inner clad within the range of from about 3.8 &mgr;m to about 10.2 &mgr;m.

Abstract: An optical transmission system includes an optical transmitting unit (10) to transmit optical signals in a transmission wavelength band above 1570 nm; an optical receiving unit to receive the optical signals; an optical fiber link optically coupling the transmitting unit to the receiving unit, at least an optical amplifying unit (100) coupled along the link and adapted to amplify the optical signals; the optical amplifying unit (100) having an amplification wavelength band including the transmission wavelength band and comprising: an input (101) for the input of the optical signals, an output (102) for the output of the optical signals, at least an erbium-doped active fiber (103a, 103b) for the amplification of the optical signals, having a first end optically coupled to the input (101) and a second end optically coupled to the output (102), a pump source (104, 106) for generating a pump radiation having a wavelength greater than 1400 nm and lower than 1470 nm, and an optical coupler (105, 107) optically coup

Abstract: An active optical amplifier in which a unitary optical amplifier constructed from a unitary optically transparent chip that has been doped so as to be optically active, amplifies incoming signal photons when excited by a pump laser of sufficient energy. The unitary optical amplifier receives input photons and pump laser energy and provides output photons that have the same spatial orientation and phase as the corresponding input photons. A laser direction and ranging (LADAR) may be constructed from the active optical amplifier by further including first imaging optics to focus the input photons onto the surface of the unitary optical amplifier and second imaging optics to focus the output photons from the active unitary optical amplifier onto a focal plane image sensor array. The electronic signals from the focal plane image sensor array may then be displayed on a conventional display.

Abstract: 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 stages. Each amplifier stage includes a tap/power extractor for removing a portion of the amplified input signal, allowing for the pump signal(s) and remaining amplified input signal to be applied as an input to the following stage.