51 results about "Supercontinuum" patented technology

The invention discloses an underwater navigation positioning method and system based on supercontinuum laser intensity correlation. The system comprises a master control system, a transmitting end underwater base station and a receiving end underwater carrier. The method comprises the following steps: firstly, a main control system generates a super-continuum laser signal with pseudo-random code information, the super-continuum laser signal is separated into optical signals of different wavelength channels through a light splitting module, and the optical signals are respectively sent to underwater base stations uniquely corresponding to the wavelength channels and are emitted; then the underwater carrier receives optical signals from a plurality of base stations, identifies a signal source base station according to wavelength identification, performs correlation operation with a locally copied pseudo-random code sequence, determines signal arrival time TOA and calculates a pseudo-range; and finally, resolving the three-dimensional coordinate and local clock error result of the underwater carrier by combining the pseudo-ranges, absolute positions and transmission delays of the underwater carrier and the at least four base stations. According to the invention, high-precision and high-robustness absolute positioning of the underwater environment is realized, and the reliability of long-time positioning and navigation of the underwater robot is enhanced.

This invention relates to the field of spectroscopic measurement technology, and particularly to a measurement system and method for measuring the concentration of high-temperature combustion gases in aero-engines. The measurement system includes a supercontinuum laser source, a first collimating mirror, a second collimating mirror, a spectrometer, and a computer. The measurement method includes acquiring the actual transmittance spectrum of the high-temperature combustion gases; calculating the theoretical transmittance spectrum of the high-temperature combustion gases; constructing constraints; fitting the actual transmittance spectrum and the theoretical transmittance spectrum into the constraints; and calculating the concentration of the high-temperature combustion gases. The measurement system has a lightweight structure, requiring only holes for mounting the laser emission and absorption devices on the inner wall of the aero-engine casing. The measurement method uses a supercontinuum laser source, which, compared to ordinary lasers used in active gas detection, offers better spatial coherence, a wider spectral adjustment range, and higher intensity, enabling the detection of more types of gases. The method uses a multi-band combustion gas absorption model to solve for the temperature of the high-temperature combustion gases, improving the accuracy of the concentration calculation.

The invention discloses an on-chip super-continuum spectrum light source based on a cascaded polarized ferroelectric material and a design method thereof. The pump light source is used for providing pump light; the pump light enters the super-continuum spectrum generation waveguide; the super-continuum spectrum generation waveguide meets the requirements that the group velocity dispersion is close to 0 under the wavelength of the pump light, the group velocity mismatch of the wavelength of the pump light and the wavelength of the frequency doubling light is close to 0, and the polarization period of the super-continuum spectrum generation waveguide meets the phase matching of frequency doubling. The polarization period of the super-continuum spectrum expansion waveguide changes along the propagation direction, and the super-continuum spectrum expansion waveguide outputs a super-continuum spectrum; the conical transition waveguide is used for connecting the super-continuum spectrum generation waveguide and the super-continuum spectrum expansion waveguide and eliminating mode mismatch between the super-continuum spectrum generation waveguide and the super-continuum spectrum expansion waveguide. The system has the advantages of low cost, high integration level and wide spectrum coverage, and is suitable for the fields of environmental monitoring, medical diagnosis, spectral analysis and the like.

A kind of mid-infrared supercontinuum light source of spatial light structure, comprising: pump source, for generating pump light;Collimating lens, for collimating pump light, output parallel light;Grating pair, by two grating parallel placement, for according to frequency to the light input to grating pair Spectral splitting is realized and the optical path of each frequency light is changed, output transmission light to roof prism;It is also used for the light that returns to grating pair from roof prism by original road to be compounded and pulse compression is realized, output compressed light to reflector;Roof prism, for the light that transmits grating pair is reflected again and transmits grating pair;Reflector, for reflecting the compressed light;Focusing lens, for focusing the compressed light reflected by the reflector;Fluoride fiber, the compressed light after focusing of focusing lens is spatially coupled into fluoride fiber at focal point, output mid-infrared supercontinuum laser.The utility model discloses in spatial light coupling system using grating pair compression pulse, the further widening of supercontinuum is realized.

The utility model discloses a pulse modulation circuit of an ultra-wideband super-continuum fiber laser, belongs to the technical field of ultra-wideband super-continuum fiber lasers, and solves the problem that the phase noise floor of a clock circuit is directly lifted due to the fact that power supply ripple coupling and LDO filter network efficiency is insufficient, for example, the output capacitance ESR is too high or a pi-type filter is missing. Comprising an input filtering module, a low dropout linear regulator module, a pi-type filter module, a clock power supply distribution module and a grounding system module. According to the utility model, high-frequency ripple filtering, voltage ripple depth suppression and residual noise absorption are carried out on power supply output through a three-stage sequential filtering framework, and finally, super-stable power supply with a phase noise base lower than-152dBc / Hz and 1kHz offset is provided for the clock circuit, so that the time sequence precision of super-continuum spectrum laser pulses is ensured.

An imaging system (400) includes an imager (410) having first and second light sensors (465, 467), the first light sensor (465) being configured to record light in a first wavelength range and the second light sensor (467) being configured to record light in a second wavelength range, an alignment mechanism (440) configured to be attached to the imager (410), an illumination source (450) configured to generate a supercontinuum light beam, and a light shaping mechanism (452) configured to transform the supercontinuum light beam into a linear strip of light (450B). The alignment mechanism (440) is configured to adjust a position of the light shaping mechanism (452) so that a back scattered light (710), resulting from a scattering of the linear strip of light (450B) from a target (620), has an intensity above a given minimum for each of the first and second light sensors (465, 467).

The discovery of a clear correlation between the Anderson localization length and the dispersion properties of highly localized TALOF modes allowed us to demonstrate that the zero dispersion wavelength can be tuned over more than 300 nm within the same fiber by selected excitation of specific modes. This enabled apparatus and methods for generating tunable, multi-octave-spanning supercontinuum (SC) spectra in a bandwidth from 460 nm to 1750 nm. Associated applications are also presented.

The invention provides a cross-octave on-chip super-continuum spectrum generation method for near-zero dispersion engineering, and the method employs the excellent third-order nonlinear characteristic of a Z-cut film lithium niobate material doped with 5% MgO, achieves the integrated dispersion characteristic of near-zero distribution through the optimization design of the geometric dimension of an optical waveguide. Secondly, by means of a low energy barrier between the pump wave and the dispersion wave, cross-octave super-continuum spectrum broadening and flat broadband short-wave band dispersion wave can be achieved no matter whether the pump wavelength is in a normal group velocity dispersion condition or an abnormal group velocity dispersion condition; finally, the experimental test result further verifies the effectiveness of the designed waveguide structure, and an on-chip super-continuum spectrum of which the 30dB spectral range covers one octave and flat short-wave band dispersion waves of which the 3dB spectral bandwidth reaches 70.1 THz and 77.3 THz are respectively obtained.

The invention discloses a high-efficiency visible light super-continuum spectrum generation method and device based on a green light pumping gradient refractive index multimode fiber, and belongs to the technical field of fiber laser. According to the method, a pulse green laser is adopted as a pumping source, the pulse green laser is coupled into a parameter-optimized multimode optical fiber with the gradient refractive index, and the gradient refractive index is obtained by exciting the synergistic effect of nonlinear effects such as geometric parameter instability and light beam self-cleaning which are unique in the optical fiber. And the high-flatness super-continuum spectrum covering the whole visible light wave band is directly and efficiently generated. The defects that a traditional photonic crystal fiber scheme is low in conversion efficiency and poor in flatness in the visible light wave band are overcome, the range and shape of an output spectrum can be accurately regulated and controlled by flexibly designing the fiber core radius, the numerical aperture and the length of the fiber, and meanwhile it is guaranteed that an output light beam is close to the diffraction limit through the light beam self-cleaning effect. According to the scheme, the system is simple in structure and high in robustness, and a novel, reliable and practical way is provided for achieving a high-performance visible light super-continuum spectrum light source.

The application discloses a kind of multispectral laser imaging radar systems based on APD array and supercontinuum laser, wavelength covering 450~2400nm supercontinuum laser is used as light source, the continuous laser output is collimated after being collimated by laser collimating system, multi-band fast selection is realized by acousto-optic tunable filter, and uniform emission is completed in combination with variable-focus laser emission optical system;Then, large field of view receiving optical system is constructed, and the echo signal is detected by APD array detector to realize multi-pixel parallel detection, the echo intensity data corresponding to different wavelengths are acquired, and the multispectral reflection information of target is formed.Finally, the laser emission time and APD array receiving time are accurately synchronized, based on time-of-flight ranging principle, the high-precision space-time information of target point cloud data and multispectral information is synchronously acquired.The application realizes the high spectral information acquisition accuracy while breaking through the efficiency and resolution limit of traditional single-point imaging mode.

The application discloses a super-surface-based continuous-order-variable perfect vortex beam generator, relates to the technical field of micro-nano optics, and aims at solving the problems of non-continuous multi-order variable order and complex variable order mode in the prior art.The generator comprises a forwardly arranged super-surface one and a super-surface two;the two super-surfaces each comprise a SiO2 substrate and a micro-nano structure array;the micro-nano structure array is composed of a plurality of cylindrical monocrystalline silicon with different diameters, the period of adjacent cylindrical monocrystalline silicon is a subwavelength size, and the layout of the plurality of cylindrical monocrystalline silicon with different diameters is formed by a phase formula.The two super-surfaces can change the relative rotation angle, thereby providing additional vortex phases with different orders for a light beam, and a perfect vortex beam with continuous variable order can be generated by using only two super-surfaces; and the application has simple structure and can increase the stability of the light beam to a certain extent.

The application discloses a method for inducing supercontinuum local dispersion wave generation in a waveguide. The method is embedding a grating structure with a limited length in an optical waveguide structure. The grating structure realizes periodic modulation of the effective refractive index of the waveguide, so as to induce supercontinuum local dispersion wave generation. The wavelength and intensity of the dispersion wave can be controlled by changing the period length, modulation depth, period number and other parameters of the grating structure. The method for inducing supercontinuum local dispersion wave generation in a waveguide can accurately control and realize supercontinuum spectrum power promotion at any specified wavelength, so as to provide a wider space for the practical application of the supercontinuum light source.

This invention discloses a high-power, broadband, tunable long-wavelength mid-infrared femtosecond laser generation device and method. The laser beam is split into a first beam and a second beam. The first beam pumps a first YAG crystal to generate a first supercontinuum, from which a signal light of a predetermined wavelength is selected. The signal light undergoes at least two cascaded optical parametric amplification stages to generate a high-power mid-infrared pump light. The second beam pumps a second YAG crystal to generate a second supercontinuum covering the long-wavelength infrared band as a seed light. This seed light is then incident on a BGGSe crystal for optical parametric amplification. Using a 1.5μm high-power femtosecond laser as the pump source, combined with the BGGSe nonlinear crystal for optical parametric amplification, the wide transmission range and high nonlinear coefficient of the BGGSe crystal are effectively utilized. Phase matching in the 6–18μm band can be achieved under 1.5μm pumping conditions, thereby obtaining a broadband, high-power, femtosecond-level laser output covering the long-wavelength mid-infrared band.

A system (12) for generating supercontinuum pulsed emission having a substantially flat spectrum, the system comprising: a fiber mode-locked oscillator (1) comprising a laser cavity (2); an amplifier (10); a non-linear optical fiber (11); the laser cavity comprises a Fiber Bragg Grating element (5) and a Semiconductor Saturable Absorber Mirror (8) configured to act as first and second mirrors respectively, the Fiber Bragg Grating element (5) having: a bandwidth between 3 nm and 15 nm, a reflectivity between 10 – 50%, and a dispersion value such that the total dispersion of the laser cavity is in the anomalous dispersion regime.

Super-resolution label-free microscopy is provided using multiplexed, temporally modulated acquisition patterns of emission point spread functions (“PSFs”). Supercontinuum ultrafast pulses can be used to enhance nonlinear processes, such as autofluorescence and harmonic generation, in order to provide super-resolution imaging of nonlinear label-free signals. Images can be reconstructed using various reconstruction techniques, including pixel reassignment, wavelet reconstruction, and deep learning model-based reconstructions.

The invention provides a multi-view spectral imaging three-dimensional reconstruction method and system based on laser-induced plasma, and the method comprises the steps: synchronously collecting an absorption image of the plasma through employing a plurality of spectral imaging detectors which are arranged at different view angles, and capturing the two-dimensional absorption distribution of the plasma through combining with supercontinuum white light illumination; and then obtaining two-dimensional distribution of the plasma density by using a Lambert-Beer law, and reconstructing three-dimensional reconstruction of the plasma density according to the multi-view two-dimensional density distribution. According to the method, non-contact, non-disturbance and high-spatial-resolution three-dimensional density diagnosis of the laser-induced plasma is achieved, high real-time performance and accuracy are achieved, and the method can be widely applied to the fields of laser processing, plasma physical research and the like.

This invention discloses a high-power, broadband, tunable long-wavelength mid-infrared femtosecond laser generation device and method. The laser beam is split into a first beam and a second beam. The first beam pumps a first YAG crystal to generate a first supercontinuum, from which a signal light of a predetermined wavelength is selected. The signal light undergoes at least two cascaded optical parametric amplification stages to generate a high-power mid-infrared pump light. The second beam pumps a second YAG crystal to generate a second supercontinuum covering the long-wavelength infrared band as a seed light. This seed light is then incident on a BGGSe crystal for optical parametric amplification. Using a 1.5μm high-power femtosecond laser as the pump source, combined with the BGGSe nonlinear crystal for optical parametric amplification, the wide transmission range and high nonlinear coefficient of the BGGSe crystal are effectively utilized. Phase matching in the 6–18μm band can be achieved under 1.5μm pumping conditions, thereby obtaining a broadband, high-power, femtosecond-level laser output covering the long-wavelength mid-infrared band.

This invention discloses a multifunctional photonic crystal fiber based on a dual-ring core structure, aiming to simultaneously achieve high-capacity communication transmission and broadband light source applications. The fiber consists of a central air hole, a double-layer composite ring core, inter-ring core air holes, and an outer cladding. The double-layer composite ring core employs a nested design, comprising an inner ring core and an outer ring core, both of which are identical five-layer composite structures. The middle layer of the composite ring core is composed of highly nonlinear soft glass SF57. The two sides of the middle layer are symmetrically distributed, composed of SF2 and LLF1 glasses with low refractive indices, respectively. Stable, low-crosstalk transmission of 332 orbital angular momentum (OAM) modes is achieved through the dual-ring core and periodic air hole structure, with effective refractive index differences for all modes exceeding a certain threshold. The optimized fiber structure design significantly reduces confinement loss to a certain level and can generate a supercontinuum covering 1147 nm to 2170 nm under 1550 nm wavelength pumping. This design improves the capacity of communication systems while meeting the multifunctional application requirements of optical imaging, frequency domain communication, and optical sensing.

The invention discloses a super-continuum spectrum laser thermal halo intensity evaluation method based on equivalent thermal distortion parameters, and relates to the technical field of transmission of high-power super-continuum spectrum laser and high-power wide-spectrum laser in a free space. The method is based on the radiation transmission principle, firstly, the equivalent absorption coefficient and the equivalent transmittance of super-continuum spectrum laser in the atmospheric transmission process are calculated, on this basis, the thermal distortion parameter spectrum is calculated, and finally, the equivalent thermal distortion parameter is obtained through laser power spectrum weighted averaging. The larger the value of the equivalent thermal distortion parameter is, the larger the intensity of the thermal halo effect is, and the influence of the thermal halo effect on the super-continuum spectrum laser is more serious. The invention provides a method for evaluating the intensity of a thermal halo effect, which is beneficial to quickly evaluating the influence degree of the thermal halo effect of the laser on laser transmission in a free space application scene.

A supercontinuum generator includes at least one dispersion compensated transmission line. Each dispersion compensated transmission line includes a pair of a first portion of and a second portion of transmission line optical waveguide that are optically connected by one pair of chirped Bragg gratings. Each chirped Bragg grating includes an optical waveguide with gratings. By interspersing the pair of chirped Bragg gratings between the pair of the first and the second portions, coherence of the spectral components of an optical frequency comb is increased. As a result, a power spectral density, of each of the spectral components of an output optical frequency comb, is increased.

This invention discloses a wide-tunable single-passband microwave photonic filter and its construction method. The filter includes a light source device for generating a supercontinuum light source, comprising a generator, an RF power amplifier, a DFB laser, a first erbium-doped fiber amplifier, a first variable optical attenuator, and a highly nonlinear fiber connected in sequence. An optical filter for selecting a certain width of supercontinuum light source is connected between the light source device and a MZI structure for spectral segmentation of the supercontinuum light source. The MZI structure is connected to a photodetector via a single-mode fiber and a second erbium-doped fiber amplifier. The photodetector is connected to the MZI structure via a vector network analyzer. This application features a simple structure, low cost, and the constructed complex coefficient filter eliminates the fundamental frequency response.

This invention provides an integrated optical system for field-of-view split-aperture imaging and laser beam expansion, belonging to the field of optoelectronic imaging technology. It includes a front-mounted common-aperture main optical system, comprising a primary mirror and a secondary mirror; an imaging branch located at the image side of the front-mounted common-aperture main optical system for receiving light signals from the target scene and focusing them; and a laser beam expansion branch located at the image side of the front-mounted common-aperture main optical system for expanding and emitting the input laser beam. This invention employs an integrated common-aperture split-aperture architecture to achieve a common optical path design for both focused and unfocused systems. It integrates focusing imaging and unfocused beam expansion optical paths with different focal lengths and field-of-view requirements under the same optical aperture, realizing the synergistic working capability of high-resolution imaging and high-magnification supercontinuum laser beam expansion.

The application discloses a kind of ultraviolet-middle infrared waveband flat type supercontinuum all-fiber laser, belong to fiber laser technical field, including dual-wavelength power amplification and beam combination structure, it includes by first wavelength power amplification substructure, second wavelength power amplification substructure, two wavelengths light output by two substructures is coupled by wavelength division multiplexer;It further includes short-wave ultraviolet waveband supercontinuum generation structure, it includes photon crystal fiber and fifth rare earth ion doped optical fiber connected in order;It further includes long-wave middle infrared waveband supercontinuum generation structure, it includes fifth fiber amplifier, mode field adapter, the high nonlinearity optical fiber of doping concentration 64mol.%-100mol.%, seventh rare earth ion doped optical fiber connected in order, three structures are connected in order.The application dual-wavelength pumped nonlinear optical fiber and introduce rare earth doped optical fiber to eliminate the mode of combination of pump residual peak, on the basis that spectrum is greatly expanded, simultaneously realize the flat output of spectrum full waveband.

The application provides a kind of on-chip f-2f self-referencing method of period taper type thin film lithium niobate optical waveguide, period taper waveguide structure is introduced to widen the phase matching bandwidth of second harmonic, make the broadband dispersion wave of supercontinuum spectrum generated by second harmonic spectrum fully cover, so as to reduce the demand of f-2f self-referencing waveguide device to pump pulse energy. ceo Beat signal; that is, the application can effectively widen the phase matching bandwidth of second harmonic, so that the second harmonic generated and the dispersion wave of supercontinuum process have wideband spectrum overlap, and on-chip f-2f self-referencing can be realized under lower pump energy, which can reduce the energy consumption by nearly 40% compared with traditional straight waveguide device.

The invention relates to a method for generating super-continuum spectrum light, comprising: providing frequency comb pump light and auxiliary pump light wherein an auxiliary center frequency is spectrally offset from a frequency comb center frequency by an auxiliary pump detuning amount; pumping a non-linear medium, the non-linear medium being associated with generating a dispersive wave at a dispersive wave frequency, the dispersive wave frequency being frequency shifted by a dispersive wave detuning amount relative to the frequency comb center frequency; performing spectral conversion on the frequency comb pump light through a cascade four-wave mixing process induced by the auxiliary pump light so as to generate cascade frequency comb light; generating a dispersive wave at the dispersive wave frequency, the generation of the dispersive wave being induced by the cascade frequency comb light, the induction being due to the integral multiple of the detuning amount of the auxiliary pump being located within the spectral range of the detuning amount of the dispersive wave; and outputting the cascaded frequency combed light and the dispersed wave, thereby providing the super-continuum spectrum light.

The application provides a kind of ultrafast time resolution measurement method and system, the system includes four components of supercontinuum white light laser generation, chirp control, multispectral collaborative imaging detection and data fusion processing;Supercontinuum white light laser generation component converts ultra-short pulse laser into supercontinuum white light laser, chirp control component divides supercontinuum white light laser into multiple wavebands of supercontinuum white light laser with time interval, multispectral collaborative imaging detection component is based on multiple wavebands of supercontinuum white light laser and is imaged to the object to be measured for spectroscopy, obtains the image of the object to be measured corresponding to each spectral component, data fusion processing component is based on multiple wavebands of supercontinuum white light laser and the image of the object to be measured corresponding to each spectral component, obtains the dynamic evolution imaging of the transient process of the object to be measured.The application realizes the dynamic evolution imaging of transient process ultrafast time resolution, and the imaging quality is high.

There is described a supercontinuum radiation source comprising: a modulator operable to modulate pump laser radiation comprising a string of radiation pulses to provide modulated pump laser radiation, the modulation being such that a selective burst of pulses is provided; and a hollow-core photonic crystal fibre operable to receive the modulated pump laser radiation and to excite a working medium contained within the hollow-core photonic crystal fibre to thereby generate supercontinuum radiation.

The application discloses a single-seed-source-based all-fiber flat ultraviolet-mid-infrared supercontinuum laser, which comprises a seed laser, two-stage ytterbium-erbium-doped fiber amplifiers, a high-nonlinear fiber NL-1550, a large-mode-field ytterbium-erbium-doped fiber amplifier, a large-mode-field ytterbium-doped fiber amplifier, a photonic crystal fiber and a passive fluorine-doped fiber which are connected in sequence; wherein the seed laser outputs seed pulse laser of 1.55 mu m, and finally outputs supercontinuum laser with a spectral range of 370-4500 nm, covering ultraviolet-mid-infrared bands. The application adopts an all-fiber structure, has high stability and portability, reduces the loss in the process of light transmission and the system complexity, realizes double-wavelength pumping through a seed source, and realizes super-flat spectral output covering ultraviolet to mid-infrared through a multi-stage amplification structure and a multi-stage nonlinear medium structure.