51 results about "Nonlinear optical fiber" patented technology

The invention discloses a near-infrared wide-spectrum pulse light source generator, belongs to the technical field of laser light source manufacturing, and aims to solve the problems of complex system structure and high cost due to the fact that a supercontinuum laser generates supercontinuum through multi-stage power amplification in the prior art. The device is composed of a first semiconductor pump laser, a first wavelength division multiplexer, a first gain optical fiber, a first filter, a first dispersion compensation optical fiber, a first high-nonlinearity optical fiber, a first isolator, an optical fiber coupler, a second semiconductor pump laser, a second wavelength division multiplexer, a second gain optical fiber, a second filter, a second dispersion compensation optical fiber, a second high-nonlinearity optical fiber and a second isolator. According to the invention, the characteristic of high mode-locked pulse energy of the Mmyshev oscillator is utilized, multi-stage power amplification is not needed, and the super-continuum spectrum can be directly generated, so that the system structure is simplified, and the cost is reduced; the laser light source can be applied to multiple fields of laser sensing, photoelectric countermeasure, remote sensing detection, optical imaging and the like.

A light source includes a mode-locked laser; a beam splitter that branches the femtosecond optical pulse train; a CW solid-state laser; a first beam combiner that outputs one side of the femtosecond optical pulse train on the same axis; a secondary nonlinear optical element that outputs a difference frequency generation and conversion optical pulse train from either a continuous wave or a femtosecond optical pulse train; an amplifier that amplifies the difference frequency generation and conversion optical pulse train; a polarization-maintaining all normal dispersion high nonlinear fiber that converts the other femtosecond optical pulse train into a supercontinuum optical pulse train; a first dispersion medium that converts the supercontinuum optical pulse train into a pulse width that is approximately the same as the difference frequency generation and conversion optical pulse train; and a second beam combiner that multiplexes and outputs the difference frequency generation and conversion optical pulse train and the supercontinuum optical pulse train.

The invention discloses an optical fiber link physical parameter estimation method based on a multichannel feature input neural operator, and belongs to the technical field of optical fiber communication. The method comprises the following steps: acquiring signals of a transmitting end and a receiving end under different channel parameters, and respectively calculating multiple groups of weighting and observation data corresponding to loss, dispersion and nonlinear effect according to a nonlinear evolution equation for describing optical signal transmission; splicing the observation data and processing the observation data into a high-dimensional complex feature sequence; a frequency domain operator block comprising a parallel complex frequency spectrum and a time domain convolution branch is designed to extract and fuse the features, and aggregation representation of the channel features is obtained through Fourier transform and frequency domain attention pooling; and outputting estimated dispersion and nonlinear real number parameters through a plurality of multi-layer perceptron and a linear projection layer. According to the method, physical priori knowledge of optical fiber transmission is integrated into the deep neural operator, so that the parameter estimation capability and the model generalization performance of long-distance, strong-dispersion and strong-nonlinearity optical fiber links are improved.

The application discloses a mode division multiplexing all-optical regenerative device, which comprises a polarization controller, a few-mode amplifier, an optical coupler, a few-mode nonlinear optical fiber, an optical carrier extractor and an optical phase shifter. Mode division multiplexing signals of multi-level pulse amplitude modulation from different users can be simultaneously regenerated by the mode division multiplexing all-optical regenerative device, the regenerated mode division multiplexing signals are amplified and shaped, and the power transfer curve of each mode channel is not affected by the change of other mode levels.

The invention discloses an all-fiber laser. The all-fiber laser comprises a pump laser, a wavelength division multiplexer, a gain fiber, an isolator, a fiber coupler, a multifunctional fiber crystal and a polarization controller, and the input end of the wavelength division multiplexer is connected with the pump laser; the input end of the gain optical fiber is connected with the output end of the wavelength division multiplexer, the output end of the isolator is connected with the output end of the gain optical fiber, the second output end of the optical fiber coupler is connected with the input end of the isolator, the first output end of the optical fiber coupler realizes laser output, and the output laser proportions of the first output end and the second output end are 10%-20% and 80%-90%; the output end of the multifunctional optical fiber crystal is connected with the input end of the optical fiber coupler, the output end of the polarization controller is used for being connected with the input end of the nonlinear optical fiber crystal, and the input end of the polarization controller is connected with the common end of the wavelength division multiplexer. The stability of the all-fiber laser is improved.

This invention discloses a high-speed sweeping fiber optic light source. The specific device includes: a mode-locked pulse light source, an optical fiber amplifier, a highly nonlinear optical fiber, and a dispersion-compensating optical fiber. The passively mode-locked pulse light source outputs a high repetition rate, wide-spectrum mode-locked pulse. Its dispersion propagation follows a parabolic differential equation similar to one-dimensional paraxial diffraction, analogous to Fraunhofer diffraction. The pulse is amplified outside the cavity by an optical fiber amplifier to increase the laser pulse energy and peak power. Then, it is broadened by the highly nonlinear optical fiber to obtain a supercontinuum light source. Finally, the pulse is stretched by a highly dispersive medium provided by the dispersive optical fiber, and the pulse frequency domain spectrum is mapped to a time domain waveform, thereby realizing a high-speed sweeping frequency light source in the time domain.

A spectral domain optical coherence tomography (OCT) system utilizes an electrowetting prism having four isolated electrodes and configured to deflect a light beam according to an actuating control signal applied to the electrodes. The control signal causes the light beam to laterally scan over a sample. The light beam is produced by a broad bandwidth laser and light from the sample and a reference path is provided to a spectrometer for analysis. The light source may be an all-normal-dispersion fiber laser seeding a gain-managed nonlinear fiber amplifier. The electrowetting prism is capable of scanning up to ±6°. The system is low power and operates at kHz speed.

The invention discloses an optical frequency comb generation device and method based on a 3 * 3 optical fiber coupler, and the device comprises a single-frequency microwave source, a phase shifter, a continuous wave laser, an intensity modulator, a phase modulator, a first connection optical fiber part, and a second connection optical fiber part. The microwave signal output end is connected with the intensity modulator or the phase modulator; the continuous wave laser comprises a laser signal output end, and the laser signal output end is connected with the intensity modulator; the intensity modulator and the phase modulator are connected with the input end of the non-linear optical annular mirror through the first connecting optical fiber part, the output end of the non-linear optical annular mirror is connected with the second connecting optical fiber part, and the non-linear optical annular mirror comprises a 3 * 3 optical fiber coupler and a non-linear optical fiber which are coupled; a 3 * 3 optical fiber coupler is adopted to form a nonlinear optical annular mirror, ultra-short pulse shaping is achieved through the interference effect between two paths of reverse transmission light fields, continuous wave background noise and pulse base side lobes are effectively eliminated, and through the design of an optical fiber coupling mode and a loop port connection mode and the selection of an input end and an output end, ultra-short pulse shaping is achieved. And the nonlinear chirp part of the pulse waveform is greatly inhibited, and the linear characteristic of the nonlinear chirp part is kept, so that the ultra-wideband optical frequency comb light source with remarkable spectral balance is realized in the high nonlinear parameter mixing process.

The present application relates to the technical field of optical fibers, in particular to a dual-wavelength femtosecond fiber laser. The laser comprises a pumping light source, which is used for outputting first-wavelength femtosecond pulse laser and a first excitation light source; a double-clad nonlinear optical fiber, which is connected to an output end of the pumping light source and is used for converting part of the first-wavelength femtosecond pulse laser into second-wavelength femtosecond pulse laser by means of using the soliton self-frequency shift effect, and outputting the remaining first-wavelength femtosecond pulse laser, the second-wavelength femtosecond pulse laser and the first excitation light source; and a holmium-doped gain fiber, which is connected to the output end of the double-clad nonlinear optical fiber and is used for amplifying the first-wavelength femtosecond pulse laser and the second-wavelength femtosecond pulse laser under the excitation of the first excitation light source. Therefore, the present application achieves the output of dual-wavelength high-energy femtosecond pulse laser in full-fiber mid-infrared lasers, achieves a compact and portable structure, good environmental adaptability and wavelength and energy advantages in practical applications such as medicine and material processing, and is applicable to vehicle-mounted scenarios, airborne scenarios, etc.

The application belongs to the technical field of ultra-short pulse laser, and particularly relates to a nonlinear fiber loop and full positive dispersion pump protection type 8-shaped cavity and a laser. The nonlinear fiber loop comprises a first circulator provided with three ports, a second circulator provided with three ports and a beam combiner. The first port of the first circulator is used to connect the third port of a coupler, the second port of the first circulator is connected with the third port of the second circulator, and the third port of the first circulator is connected with the output end of the beam combiner. The first port of the second circulator is used to connect the fourth port of the coupler through a first gain fiber, the second port of the second circulator is connected with the signal end of the beam combiner, and the first input end of the beam combiner is connected with a first pump light source.

The invention discloses a high-energy and short-period mode-locked pulse fiber laser and an emission method, and relates to the technical field of lasers, the high-energy and short-period mode-locked pulse fiber laser comprises a high-power isolator, and an erbium-doped mode-locked fiber laser and a thulium-doped fiber amplifier which are respectively arranged at two sides of the high-power isolator, the erbium-doped mode-locked fiber laser is connected with the high-power isolator through a high-nonlinearity optical fiber, the thulium-doped fiber amplifier comprises a first signal pumping beam combiner, a second signal pumping beam combiner, a first pumping source and a second pumping source, the first signal pumping beam combiner is connected with the second signal pumping beam combiner through a thulium-doped optical fiber, and the second pumping source is connected with the erbium-doped mode-locked fiber laser through a thulium-doped optical fiber. The erbium-doped mode-locked fiber laser, the high-power isolator, the first signal pumping beam combiner and the second signal pumping beam combiner are arranged on the same straight line, so that the ultra-wide spectrum is provided, the structure of the laser is simplified, amplification of specific wavelengths with few periods and high energy is realized, diversified application requirements are met, and the application range is widened. And the flexibility and multifunctionality of the laser are improved.

The utility model relates to the field of ultrafast lasers, and provides a tunable low-repetition-frequency optical fiber optical frequency comb light source. Comprising an all-polarization-maintaining ultrafast fiber laser seed source, a fiber pre-amplification stage module, a fiber main amplification stage module, a grating pair dispersion matching module, a super-continuum spectrum generation module and an f-2f self-reference detection module which are sequentially arranged along a light path. The full polarization-maintaining ultrafast fiber laser seed source is used for outputting continuously tunable signal light with low repetition frequency; the optical fiber pre-amplification stage module and the optical fiber main amplification stage module are used for carrying out self-similarity amplification and power amplification on the input signal light in sequence; the grating pair dispersion matching module is used for performing dispersion matching on the amplified signal light; the super-continuum spectrum generation module is used for coupling the signal light subjected to dispersion matching into a high-nonlinearity optical fiber to generate a super-continuum spectrum light source; and the f-2f self-reference detection module is used for measuring the super-continuum spectrum light source to obtain a light frequency comb with low repetition frequency.

A mid-infrared laser generation system based on dispersion-managed soliton bunch pulses. The system can achieve high-power, high-efficiency and high-proportion mid-infrared laser output, and has the advantages of an all-fiber configuration, a compact structure and a high power proportion in a longer-wavelength region of a mid-infrared spectrum. A pulsed fiber laser device generates a nanosecond pulse laser in a 1.5-micron band. A fiber pulse stretcher is made of a single-mode silica fiber, splits nanosecond pulses into a plurality of ultrafast soliton pulses by means of a nonlinear effect, and performs spectral energy conversion from 1.5 microns to 2.4 microns. A fiber laser amplifier further increases the output power of a stretched pulse laser and extends a spectrum to a 2.7-micron band, and also increases pulse energy beyond a 2.3-micron band. A fiber mode field adapter efficiently couples into a nonlinear fiber pulses generated in the fiber laser amplifier. The nonlinear fiber extends a laser to a mid-infrared 3-5-micron band, thereby achieving high-power, high-efficiency and high-proportion mid-infrared laser output.

The present invention discloses a high-repetition-rate all-fiber ultrashort pulse laser, comprising: a pump source, a wavelength division multiplexer, an erbium-doped fiber, and a highly nonlinear fiber are connected in sequence by optical fibers downstream of the optical path of the pump source; a coupler is connected by an optical fiber downstream of the optical path of the highly nonlinear fiber; a mode-locking device is connected by an optical fiber downstream of the optical path of the coupler; the light inlet of a circulator is connected by an optical fiber downstream of the optical path of the mode-locking device; the first light outlet of the circulator is connected by an optical fiber along the optical path direction to a first fiber Bragg grating; the optical path downstream of the first fiber Bragg grating is connected by an optical fiber to a second fiber Bragg grating; a grating wavelength tuning device is connected to the second fiber Bragg grating; and the second light outlet of the circulator is connected by an optical fiber along the optical path direction to the light inlet of the wavelength division multiplexer. By means of the wavelength adjustment device, the present invention realizes the change of the center wavelength interval between the two gratings, and further realizes a high-repetition-rate ultrashort pulse laser with adjustable repetition frequency.

The invention discloses a beam-expandable dispersion-adjustable high-nonlinearity polarization-maintaining preform, an optical fiber and a manufacturing method of the polarization-maintaining optical fiber, and a core rod, the core rod comprises a core layer and an inner cladding, the core layer has a first type of doping, and the first type of doping is germanium doping; the inner cladding has a second type of doping, and the second type of doping is germanium-fluorine co-doping; the stress rod is provided with a third type of doping so as to realize a birefringence function; the sleeve is provided with a first sleeve inner hole which is located in the center of the sleeve and matched with the core rod, and two second sleeve inner holes which are symmetrically distributed on the two sides of the first sleeve inner hole and matched with the stress rods. According to the method, the problem of core cracking of the polarization-maintaining preform with the high numerical aperture during processing is solved, the problem of overlarge welding loss between the high-nonlinearity optical fiber and the conventional polarization-maintaining optical fiber is solved by controlling the expansion coefficient of the inner cladding, and meanwhile, the prepared optical fiber has the properties of high nonlinearity effect, capability of expanding beams to reduce the welding loss, adjustable dispersion and the like.

The application discloses a pulse ultrafast measurement system based on a time domain amplification method, comprising a reference pulse generation device, wherein the reference pulse generation device is sequentially connected with a first dispersion compensation optical fiber, a first power amplification device and a pulse shaping device; the pulse shaping device is connected with a light combiner; the light combiner is sequentially connected with a high nonlinear optical fiber, a first filter, a third dispersion compensation optical fiber, a second power amplification device and a first oscilloscope; the application further comprises a signal to be measured, wherein the signal to be measured is connected with a second dispersion compensation optical fiber, and the second dispersion compensation optical fiber is connected with the light combiner; the application further discloses a pulse ultrafast measurement method based on the time domain amplification method.

An assembly comprising a nonlinear element configured to generate broadband radiation from input radiation coupled into the nonlinear element. The assembly further comprises an optical element downstream of the nonlinear element, the optical element being configured to reflect a portion of the broadband radiation back into the nonlinear element. The nonlinear element is typically a nonlinear optical fiber, such as a hollow-core photonic crystal fiber (HC-PCF).

The utility model discloses an ultraviolet optical fiber optical parametric oscillator based on tunable picosecond green light. The ultraviolet optical fiber optical parametric oscillator comprises a high-power wavelength and repetition frequency adjustable 1 [mu] m laser system, a high-power second harmonic generation device and an optical fiber optical parametric oscillator, the high-power wavelength and repetition frequency adjustable 1 [mu] m laser system comprises a mode-locked fiber laser, a pulse stretcher, an adjustable fiber filter, a fiber pre-amplifier, a fiber collimator and a solid amplifier. According to the utility model, the wavelength of ultraviolet laser can be flexibly adjusted; through a narrow-band filtering technology, the generation efficiency of the ultraviolet laser is improved; an optical parametric oscillator based on a nonlinear optical fiber is designed, a more compact resonant cavity structure is realized, the influence of a heat effect on system efficiency and stability is inhibited, and ultraviolet laser with an excellent light spot mode can be output; the dispersion parameter of the nonlinear optical fiber can be regulated and controlled, so that the phase matching condition of four-wave mixing is optimized, and the efficiency and wavelength tuning range of ultraviolet laser are further improved.

This invention provides a U-band high-energy square-wave pulsed Raman light source module. It first achieves initial stable amplification of the seed light through forward pumping with a 100-watt pump source, followed by high-energy main amplification through reverse pumping with a kilowatt-level pump source. Both stages of Raman amplification utilize highly nonlinear optical fibers as the gain medium to significantly enhance the stimulated Raman scattering effect, efficiently converting pump light energy into signal light and improving overall Raman gain and energy conversion efficiency. Simultaneously, it balances the stability of the amplification process with the integrity of the pulse waveform, thereby achieving a smooth, step-by-step amplification of the U-band pulsed seed light. Ultimately, it stably outputs high-energy U-band square-wave pulsed light with a single pulse energy ≥5μJ and a pulse width of 80–120ns, significantly improving the light source's output performance and better meeting the application requirements of long-distance fiber optic communication expansion and atmospheric methane remote sensing.

The invention belongs to the technical field of gas curing, and discloses a gas curing method based on a high-brightness broadband light source, which comprises the steps of carrier gas treatment, solid gas light source construction, solid gas light path construction, solid gas treatment, quality detection and the like. Compared with an existing external irradiation technology, the method adopts a mode that pulses enter a nonlinear optical fiber, a high-brightness broadband light source is generated by utilizing a nonlinear effect, the light source has excellent light beam quality, wide spectrum and high brightness, almost all defects of the optical fiber have corresponding wavelength energy to directly reach a fiber core to improve the performance of the optical fiber, and the optical fiber performance is improved. Gas molecules are more stably left in the material, the carrier gas curing efficiency is improved, defects are reduced, and the service life of the optical fiber is prolonged.

The invention discloses a demultiplexing comb-shaped Brillouin light source generating device for spectrum synthesis, which comprises a laser generator, a high-nonlinearity optical fiber and a demultiplexing grating, and is characterized in that the laser generator is used for modulating and generating first pumping comb-shaped laser and first signal comb-shaped laser, the high-nonlinearity optical fiber is connected with the laser generator, and the demultiplexing grating is connected with the high-nonlinearity optical fiber; the first pumping comb-shaped laser and the first signal comb-shaped laser are used for reversely transmitting the first pumping comb-shaped laser and the first signal comb-shaped laser, so that the first pumping comb-shaped laser and the first signal comb-shaped laser form comb-shaped Brillouin laser with a preset frequency under the action of stimulated Brillouin gain, and the demultiplexing grating is used for separating the comb-shaped Brillouin laser with the preset frequency into a preset frequency spectral line. According to the invention, by adjusting the frequency interval difference between the first pumping comb laser and the first signal comb laser, under the action of the spectrum vernier effect, the asynchronous light field can be used for driving and generating the comb Brillouin laser with the adjustable frequency interval.

The application relates to the field of optical technology and discloses a second-order soliton trap transmission state regulation method based on an optical event horizon simulation, which comprises the following steps: preparing a second-order soliton pulse and an external probe pulse, wherein the second-order soliton pulse is generated through the balance of dispersion and nonlinearity in a nonlinear optical fiber, the external probe pulse is a weak power pulse, the group velocity parameter of the second-order soliton pulse and the external probe pulse is measured, and group velocity matching and group velocity mismatch conditions are set; through accurate setting of the group velocity matching and mismatch conditions and quantitative calculation of the refractive index change caused by the soliton pulse based on the Kerr effect, an equivalent event horizon is defined, definite physical parameter benchmarks and stable potential well environments are provided for transmission state regulation, the stability of a soliton potential well action boundary can be determined and ensured, the transmission state misjudgment problem caused by potential well drift and distortion is overcome, and the accuracy of the regulation process and the predictability of the result are ensured.

A supercontinuum source including a pump light source arranged to emit pump light and a nonlinear fiber having a core arranged to receive the pump light. The supercontinuum includes infrared wavelengths generated in the nonlinear fiber from the pump light. The nonlinear fiber has a dispersion profile including a zero dispersion wavelength, a positive peak value at a peak wavelength longer than the zero dispersion wavelength, a minimum value of dispersion at a minimum wavelength longer than the peak wavelength. The pump light is arranged to include substantial energy at one or more preferred pump wavelengths which are 10 nm longer than the zero dispersion wavelength or more. Also, a supercontinuum pump source including a nonlinear fiber having a core including a fluoride glass and having a core diameter smaller than 7 μm, where the fiber has a numerical aperture of more than 0.26.

A spectrometer system is described. The system comprises a signal input port and a pump input port, respective signal and pump dispersion fibers, a nonlinear optical fiber section, and an output dispersion fiber. The dispersion fibers are configured to apply predetermined spectral dispersion on light input associated with signal and pump inputs. The nonlinear optical fiber section is configured to receive dispersed signal and pump waves and enable nonlinear interaction between the signal and pump waves. The output dispersion fiber is configured to receive light resulting from said nonlinear interaction and apply predetermined dispersion to the received light, thereby providing output light having mapping between time and spectral components of the input signal. Wherein at least one of the signal input port and pump input port comprises temporal speckle generating unit configured to affect optical pulses passing through to induce temporal speckles within said optical pulses.

The invention discloses a tunable femtosecond soliton fiber laser, which belongs to the technical field of solid lasers and comprises a pumping source, a wavelength division multiplexer, a first focusing lens, a periodically poled nonlinear crystal, a second focusing lens, a positive dispersion high nonlinear fiber and an output coupler which are connected in sequence, and one output port of the output coupler is connected with the wavelength division multiplexer. According to the invention, only two focusing lenses are adopted to form the cavity, and the length ratio of the cavity is small; the two lenses are matched with the positive-dispersion high-nonlinearity optical fiber, during wavelength tuning, the focusing lens does not need to be translated continuously, intracavity dispersion management is achieved directly by adjusting the length of the optical fiber, then chirp-free pulses are output, 1.7-2.3 [mu] m tunable femtosecond soliton source output with high stability and high integration is achieved, the problem of a near-infrared femtosecond seed source can be solved, and the near-infrared femtosecond soliton source can be used as a near-infrared femtosecond soliton source. And the problem of expensive and complex system design caused by careful control of intra-cavity dispersion and cavity length required by stable operation of the femtosecond OPO can be solved.

The invention provides a code conversion system and method based on a coherent light orthogonal frequency division multiplexing system, and the system comprises a first low-loss band-pass filter which is used for processing an electric signal obtained after 16QAM signal conversion and then transmitting the processed electric signal to a pump laser CW1; the second low-loss band-pass filter is used for processing the electric signal converted from the QPSK signal and then sending the processed electric signal to the pump laser CW1; the pump laser CW1 is used for loading the output of the first low-loss band-pass filter and the output of the second low-loss band-pass filter to the optical laser; the first high-order nonlinear optical fiber HNLF1 is used for coupling the output of the optical laser and the output of the pump laser CW2; the second high-order nonlinear optical fiber HNLF2 is used for coupling the output of the first high-order nonlinear optical fiber and the output of the pump laser CW3; and the OFDM demodulator is used for demodulating and outputting the output of the second high-order nonlinear optical fiber.

The invention discloses an ultraviolet optical fiber optical parametric oscillator based on tunable picosecond green light. The ultraviolet optical fiber optical parametric oscillator comprises a high-power wavelength and repetition frequency adjustable 1 [mu] m laser system, a high-power second harmonic generation device and an optical fiber optical parametric oscillator body. The high-power wavelength and repetition frequency adjustable 1 [mu] m laser system comprises a mode-locked fiber laser, a pulse stretcher, an adjustable fiber filter, a fiber pre-amplifier, a fiber collimator and a solid amplifier. According to the invention, the wavelength of the ultraviolet laser can be flexibly adjusted; through a narrow-band filtering technology, the generation efficiency of the ultraviolet laser is improved; an optical parametric oscillator based on a nonlinear optical fiber is designed, a more compact resonant cavity structure is realized, the influence of a heat effect on system efficiency and stability is inhibited, and ultraviolet laser with an excellent light spot mode can be output; the dispersion parameter of the nonlinear optical fiber can be regulated and controlled, so that the phase matching condition of four-wave mixing is optimized, and the efficiency and wavelength tuning range of ultraviolet laser are further improved.

An optical-resolution photoacoustic microscopy (OR-PAM) system for visualizing water content deep in biological tissue uses an all-fiber 1930-nm hybrid optical parametrically-oscillating emitter. The emitter includes a tunable laser source whose output is amplified by a first erbium-doped fiber amplifier (EDFA). The output of the first amplifier is modulated with a Mach-Zehnder amplitude modulator that receives an RF signal with a nanosecond pulse width and a multiple kilohertz repetition rate. A second EDFA further amplifies the signal and passes it to a fiber circulator that in turn delivers it to a 1950 / 1550 mm fiber wavelength-division-multiplexing coupler WDM. The coupler introduces the signal to a cavity that includes a spool of highly nonlinear fiber and a Thulium-doped fiber amplifier TDFA. From the TDFA the signal reaches a 50 / 50 fiber coupler that sends part to a second output TDFA and guides part back to the cavity through a port of the WDM.

A kind of multi-threshold phase encoding-based all-optical quantization system belongs to all-optical analog-digital conversion field.It includes high repetition frequency femtosecond pulse light source,1×M optical splitter,phase-shifted optical quantization module, soliton self-frequency shift module and multi-threshold encoding module;The phase-shifted optical quantization module is M-path electro-optic modulator;The soliton self-frequency shift module includes first M-path high nonlinear fiber,M-path single-mode fiber and second M-path high nonlinear fiber;The multi-threshold encoding module includes M wavelength division multiplexer,M×N optical delay line array,M×N photodetector array and encoding module.The present application uses multi-threshold encoding module of phase encoding,realizes simultaneous judgment of multiple threshold points on power transmission curve of M electro-optic modulators, solves code type repetition problem of all-optical quantization system,realizes more effective quantization states with less channel number,improves quantization precision.Meanwhile,quantization bit number of the present application is improved to log2(2MN).

The invention belongs to the technical field of optical fibers, and discloses an ultra-flat super-continuum spectrum light source and a generation method, the ultra-flat super-continuum spectrum light source comprises a pulse laser seed source, a stretcher, a single-mode amplifier, a double-cladding ytterbium-doped optical fiber amplifier, a high-nonlinearity optical fiber and an end cap which are connected in sequence, and the output end of the pulse laser seed source is connected with the input end of the stretcher; the output end of the stretcher is connected with the single-mode amplifier; the single-mode amplifier comprises a wavelength division multiplexer, a first pumping LD, a single-mode ytterbium-doped fiber and an isolator; the double-cladding ytterbium-doped optical fiber amplifier comprises a second pumping LD, a pumping signal beam combiner and a double-cladding ytterbium-doped optical fiber, and the signal end and the pumping end of the pumping signal beam combiner are connected with the output end of the isolator and the output end of the second pumping LD respectively; the output end of the double-cladding ytterbium-doped optical fiber is connected with the input end of the high-nonlinearity optical fiber; the output end of the high-nonlinearity optical fiber is connected with the end cap; the spectrum can cover the range of 414-1860 nm at 3dB, the use length of the high-nonlinearity optical fiber is shortened, the compactness, stability and reliability of equipment are ensured, and the cost and the installation and maintenance difficulty are reduced.