1789 results about "Laser fiber" patented technology

The invention discloses a three-dimensional cutting dynamic parameter adjusting system and method based on deep learning, and relates to the technical field of application of three-dimensional five-axis fiber laser cutting machines in the automobile manufacturing industry, and the three-dimensional cutting dynamic parameter adjusting system comprises a multi-mode sensor cluster, an edge calculation unit, a closed-loop control module and an AI model library, the multi-mode sensor cluster collects cutting data, the edge calculation unit receives the multi-mode sensor data and outputs dynamic adjustment parameters, and the closed-loop control module transmits the dynamic parameters to the laser generator and the five-axis motion controller through a high-speed communication bus to form a'sensing-decision-execution 'closed loop. The cutting state and risk are sensed in real time by designing a multi-mode sensor for collaborative decision, the problems that manual experience depends on and dynamic response lags are solved, the reject ratio is reduced, and the response speed is increased.

The invention provides an ultra-pulse thulium fiber laser therapy apparatus which comprises a laser, an electrical device and a coupler, the laser is connected with the coupler through a thulium fiber, the laser and the coupler are respectively connected with the electrical device through circuits, and the electrical device is connected with the coupler through a thulium fiber. The electrical device controls the operation of the laser and the coupler, the optical fiber is a thulium optical fiber emitted by the laser, and the wavelength of the laser is 1940 nanometers. The ultra-pulse thulium fiber laser therapy apparatus replaces a previous water cooling device and adopts a 1940nm laser internal air cooling device, so that the ultra-pulse thulium fiber laser therapy apparatus is more compact in structure, lighter in weight and smaller in size, and the problems of noise, frequent maintenance and replacement and the like caused by a large cooling-water machine are solved.

The invention belongs to the technical field of optical fiber laser welding, and particularly relates to optical fiber laser welding equipment which comprises a rack, a conveying mechanism used for conveying a battery module is arranged in the rack, an XYZ-axis moving mechanism is installed on one side of the rack, a laser welding device is installed on the XYZ-axis moving mechanism, and a conveying belt is connected to one side of the end of the rack. The conveying mechanism comprises two sets of transmission shafts, the two sets of transmission shafts are rotationally installed in the rack, chain wheels are installed on the two sets of transmission shafts, the two sets of chain wheels are meshed with a chain, a plurality of sets of shifting forks used for containing battery modules are arranged around the chain, and one ends of the shifting forks are fixedly connected with the chain. According to the battery module welding device, feeding, welding and discharging of the battery module can be conducted at the same time, the automation rate of the device is increased, meanwhile, the battery module can be continuously welded, and the welding efficiency of the battery module is improved.

An article of manufacture including a fiber optic termination of a small core optical fiber for use with a surgical laser apparatus (the output from which may be characterized by a high M2 factor) or other high-power or high-energy laser (including an appropriate fiber laser) is configured for safe and efficient coupling of light at a large laser focal point and / or to enable the process of coupling of radiant intensities exceeding the silica fiber damage thresholds and / or those ionizing the air if fully focused therein. The termination may include a glass cylinder structured to include a core region and a glass cladding region the ratio of dimensions of which is substantially equal to the ratio of respectively-corresponding dimensions of the employed optical fiber. A method of propagating light through such article of manufacture.

The invention provides a quasi-continuous thulium-doped fiber laser capable of synchronously suppressing relaxation oscillation and self-pulse, relates to the technical field of fiber laser, and is used for simultaneously realizing suppression of a self-pulse effect and a relaxation oscillation peak. Comprising a continuous driving module, a pulse driving module, a semiconductor laser pumping source, a high-reflectivity fiber bragg grating, a low-reflectivity fiber bragg grating, a beam combiner, a thulium-doped gain fiber, a passive fiber, a cladding pumping stripper and a laser output port, the continuous pump light and the pulse pump light are respectively driven by the continuous driving module and the pulse driving module to output continuous pump light and pulse pump light; the high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating form a resonant cavity structure, the thulium-doped gain fiber serves as a gain medium of the thulium-doped fiber laser and absorbs pump light to generate population inversion, laser oscillation is formed by combining the resonant cavity of the laser, relaxation oscillation suppression is achieved, and meanwhile longitudinal mode distribution of the laser is effectively disrupted.

The invention discloses a high-power intermediate infrared fiber laser. The fiber laser is composed of a first pumping source, a second pumping source, a pumping beam combiner, a high-reflectivity fiber grating, a low erbium-doped fluoride fiber, a low-reflectivity fiber grating, a cladding light filter, a fiber end cap, a collimating lens and a dichroscope. The mode of combining erbium ion ground state transition achieved through fiber core pumping and erbium ion excited state transition achieved through cladding pumping is adopted, mid-infrared laser upper energy level particle number accumulation is obtained, and meanwhile laser lower energy level particles are effectively consumed through the cladding pumping transition process. And the population inversion state of the laser system is kept, and the particle circulation rate and the quantum efficiency from the pump light to the intermediate infrared laser are improved, so that the generation of high-power and high-efficiency intermediate infrared fiber laser is realized.

The invention provides a downlink data transmission method, device and system for laser fiber power supply application, and the method comprises the steps: carrying out the differential coding of downlink data to be transmitted through a transmitting end, and obtaining a data bit sequence; mapping the data bit sequence into a modulation symbol sequence by adopting a single-carrier phase modulation mode; performing digital-to-analog conversion on the modulation symbol sequence to obtain an analog signal; and outputting downlink energy and downlink data through an energy optical fiber according to the analog signal. According to the invention, the signal frequency spectrum is moved to be far away from the direct current frequency through differential coding and single carrier phase modulation, so that the interference of direct current laser energy on signal detection is minimized, the signal-to-noise ratio is improved, the inter-symbol interference is reduced, and a receiving end is ensured to have enough signal-to-noise ratio to reliably detect data.

The invention belongs to the technical field of laser welding, and discloses a multi-parameter cooperative control laser welding method and system.The method comprises the steps that a laser energy control model is established based on material strength-thickness-gap ternary coupling, and the output power of an optical fiber laser is controlled; coaxial three-layer gradient gas is adopted for protection of a welding area, preheating before welding and double-temperature-zone gradient annealing after welding are adopted, the output power of an optical fiber laser and the three-layer gradient gas protection flow are regulated and controlled in real time through combination of multiple sensors and a control algorithm, the temperature of a heat affected zone is monitored in real time, and a cooling nozzle is controlled for cooling. And continuous parameter optimization is achieved through machine learning, and multi-parameter control laser welding is achieved.

The invention relates to a single-photon laser radar three-dimensional imaging system and method. An optical fiber laser is used for actively illuminating an imaging target; the single-photon APD array detector is used for receiving a laser echo signal reflected by a target; the near-infrared detector is used for realizing aiming; the upper computer is used for parameter setting and data receiving of the optical fiber laser, the single-photon APD array detector and the near-infrared detector, receiving active laser three-dimensional imaging data in a three-dimensional imaging state and realizing real-time display of a depth image and an intensity image; and the information processing board card is used for realizing synchronous triggering of the fiber laser and the single-photon APD array detector and data communication between the upper computer and the fiber laser and the single-photon APD array detector, and realizing preprocessing and three-dimensional reconstruction of APD data based on a time correlation single-photon counting method and in combination with space-time correlation characteristics of laser echo signals. According to the invention, the problem of insufficient detection capability of a single-photon laser three-dimensional imaging method under all-weather and low-signal-to-noise-ratio conditions is solved.

The invention discloses a narrow pulse generation system and method of an FPGA integrated fiber laser, and belongs to the field of all-digital fiber laser control. The narrow pulse generation system comprises a multi-phase clock generation module, a dynamic delay chain module, a pulse width search module, a signal selection module, a logic operation module, a frequency control module, a self-calibration module and an LVDS driving module which are in synergistic effect. The multi-phase clock generation module is used for realizing rough delay adjustment of nanosecond stepping; the dynamic delay chain module is used for realizing fine delay adjustment of picosecond stepping; therefore, based on the FPGA integrated design, an external delay chip and a high-frequency peripheral circuit are not needed, the hardware complexity and cost are reduced, and the anti-interference capability is high; picosecond-level stepping pulse width adjustment is realized through a two-level structure of nanosecond-level coarse adjustment and picosecond-level fine adjustment, and the limitation of a traditional FPGA (Field Programmable Gate Array) integration scheme is broken through; time delay deviation caused by environment change and hardware drift is considered, temperature compensation and TDC calibration are carried out, and the stability of pulse width is ensured.

A high-brightness and high-power fiber laser adopts an oscillator structure and comprises a pumping module, a high-reflectivity fiber grating, a gain fiber, a low-reflectivity fiber grating and a cladding light filter, the gain fiber is a rare earth ion doped ZBLAN fiber which takes ZBLAN as a matrix material and is of an all-solid-state anti-resonance structure, and the low-reflectivity fiber grating is a rare earth ion doped ZBLAN fiber which is of an all-solid-state anti-resonance structure. The gain optical fiber comprises a fiber core area, a cladding area, an anti-resonance area and a coating layer, the anti-resonance area is composed of at least one capillary tube set, each capillary tube set comprises a plurality of capillary tubes, the capillary tubes in each capillary tube set are annularly arranged on the periphery of the fiber core area with the fiber core area as the center, and the cladding layer is arranged on the cladding layer. The matrix material in each capillary tube and the matrix material in the cladding region are the same and are ZBLAN, and the matrix material ZBLAN in the fiber core region is doped with dysprosium ions. According to the invention, the rare earth doped all-solid-state anti-resonance optical fiber is adopted as the gain optical fiber, so that high-brightness, high-power and high-efficiency output can be realized.

The invention relates to the technical field of fiber laser rapid interlocking protection scheme design, in particular to a fiber laser rapid interlocking protection circuit, and aims to solve the problems of long protection delay and low reliability of an MOPA structure laser in an abnormal state. The circuit comprises an interlocking protection bus, an interlocking control circuit and a multi-stage interlocking switch circuit. When an abnormity occurs, the interlocking control circuit detects a signal and triggers the switch circuit to quickly respond through bus level change: the main amplification stage LD is immediately turned off by the main amplification interlocking switch circuit, and the pre-amplification stage LD is sequentially turned off after the pre-amplification interlocking switch circuit delays. Therefore, sub-millisecond protection is realized, the working time sequence of the laser is strictly followed, and damage expansion is avoided. The circuit is integrated in the laser without depending on an external system, so that the reliability is improved and the structure is simplified. The method is suitable for various fiber lasers, and effectively prevents burning failure.

The invention relates to the technical field of lasers, in particular to an air-cooled fiber laser. The air-cooled fiber laser comprises a heat dissipation structure which comprises a pumping source radiator and a fiber coiling radiator which are connected, the pumping source radiator is provided with a first air channel, the fiber coiling radiator is provided with a second air channel, and the first air channel and the second air channel are communicated with each other; the pumping source is arranged on the pumping source radiator so as to transfer heat into the pumping source radiator; the active fiber is wound on the fiber coiling radiator; a forced heat exchanger. The pumping source radiator and the coiled fiber radiator are separated, and the independently designed structure breaks through the limitation that the size is difficult to reduce due to mutual restriction of the traditional integrated radiating structure. Due to the modularized and distributed layout, each heat dissipation unit can be subjected to optimal size design according to the thermal load of the heat dissipation unit, so that the structure is compact and reasonable, the size of the laser is reduced, the overall size and weight are reduced, and portability and light weight are realized.

A system for preventing inadvertent actuation of a medical device. The system includes an elongate tube having a proximal end, a distal end, and a lumen extending from the proximal end to the distal end. The lumen is configured to receive a medical device configured to transition between an actuated state and an inactive state. The device further includes a detection system configured to determine a position of a distal end of the medical device relative to the distal end of the elongate tube. The detection system includes a transmitting element and a receiving element.

The invention belongs to the technical field of laser application, and discloses a feedback type multi-wavelength optical fiber laser shaping and amplifying system which comprises a laser light source, an optical fiber frequency doubling device and a laser shaping and amplifying mechanism. The laser shaping and amplifying mechanism comprises a laser shaping and amplifying branch or more than two laser shaping and amplifying branches which are arranged in sequence; the laser shaping and amplifying branch comprises a feedback type laser shaping device and an optical fiber gain amplifying device; the optical fiber frequency doubling device is used for carrying out selective frequency conversion on fundamental frequency laser output by the laser light source; the feedback laser shaping device is used for carrying out waveform shaping on target wavelength laser; and the optical fiber gain amplification device is used for performing gain amplification on the shaped target wavelength laser. The device has the advantages of being simple in structure and high in expansibility, is suitable for being used in an optical fiber laser application system, and is used for modulating laser frequency, improving multi-wavelength laser waveforms and improving multi-wavelength laser output energy.

The invention discloses a high-power picosecond pulse train laser with programmable sub-pulse energy and a method, and relates to the related technical field of lasers, the high-power picosecond pulse train laser comprises a mode-locked fiber laser, an acousto-optic modulator and a solid amplification chain which are sequentially arranged along an optical transmission path; the mode-locked fiber laser generates a mode-locked picosecond pulse sequence; the acousto-optic modulator performs pulse selection and pulse string grouping on the mode-locked picosecond pulse sequence, and performs pre-programming shaping on sub-pulse energy in a pulse string according to set intensity distribution to generate a pre-shaped pulse string; the solid amplification chain comprises at least one stage of solid amplifier, and the solid amplifier comprises a dichroscope, a laser gain crystal, a coupling optical assembly and an LD pumping source; and the dichroscope is used for focusing the pre-shaped pulse string amplified at the previous stage and the LD pump light transmitted by the coupling optical assembly into the laser gain crystal. Independent programmable regulation and control of the energy of each sub-pulse in the pulse string are realized, and the energy distribution of each sub-pulse in the pulse string can be flexibly adjusted.

The invention relates to the technical field of target distance detection and 3D scanning reconstruction, and discloses a coaxial scanning type ultra-long distance detection laser radar system, which comprises a laser light source module, which adopts a 1550nm optical fiber laser to output high-power laser, and ensures sufficient laser energy and human eye safety; according to the invention, by adopting the high-power 1550nm fiber laser, the ultra-long distance detection is realized on the premise of ensuring the safety of human eyes, and the detection range of more than 10km can be reached, so that the limitation that the detection distance of the traditional laser radar is only 500m is broken; according to the invention, by selecting the 1550nm laser device which is safer to human eyes and greatly improving the laser power to kilowatt and even myriawatt levels, stronger echo signals are realized, so that the detection signal-to-noise ratio is remarkably improved; the micro-lens array is adopted to replace a traditional DOE diffractive optical element, efficient beam shaping of a one-dimensional or two-dimensional dot matrix is achieved through flexible regulation and control of the curvature radius and the distance of the micro-lenses, meanwhile, the manufacturing cost is reduced, and the design freedom degree is expanded.

The invention discloses a rotary shrinkage type secondary coupling device and a laser fiber conduit thereof, the rotary shrinkage type secondary coupling device comprises a mounting seat, a first mounting cylinder and a second mounting cylinder, the first mounting cylinder and the second mounting cylinder are fixedly connected to two sides of the mounting seat, and a rotary sleeve assembly is rotatably mounted in the first mounting cylinder to clamp a large-core-diameter fiber group. A sliding sleeve assembly is slidably sleeved with the second installation cylinder, a small-core-diameter optical fiber set is clamped, and the laser overlapping area of a laser optical fiber guide pipe in the rotary sleeve assembly and a laser optical fiber guide pipe in the sliding sleeve assembly is controlled by rotating the rotary sleeve assembly. And the telescopic distance adjusting assembly is used for controlling and adjusting the distance between the laser optical fiber guide pipe in the rotary sleeve assembly and the laser optical fiber guide pipe in the sliding sleeve assembly, so that controllable coupling of the large-core-diameter optical fiber group and the small-core-diameter optical fiber group is realized, and coupling of various types of small-core-diameter optical fiber groups can be conveniently and quickly adapted. And moreover, while the passing ability and the treatment effect of the catheter are ensured, the large-core-diameter optical fiber group can be repeatedly used only by abandoning the small-core-diameter optical fiber group part, so that the cost of an anti-ultraviolet optical fiber material is greatly saved.

The invention discloses a multi-core all-solid-state anti-resonance optical fiber and a multi-wavelength optical fiber laser system. The multi-core all-solid-state anti-resonance optical fiber comprises an inner cladding area, at least two fiber core structures arranged in the inner cladding area and an outer cladding area or a coating layer area arranged on the periphery of the inner cladding area. Each fiber core structure comprises a fiber core area and an anti-resonance area, the anti-resonance area is composed of at least one capillary tube group, each capillary tube group comprises a plurality of capillary tubes, and the capillary tubes in each capillary tube group are annularly arranged on the periphery of the fiber core area by taking the fiber core area as the center; the optical fiber matrixes filled in the capillaries in the anti-resonance area are the same, and the refractive index of the anti-resonance area is n3gt; the refractive index n2 of the inner cladding region is equal to the refractive index n1gt of the fiber core region; and the refractive index of the outer cladding region or the coating layer region is n4. The optical fiber provided by the invention is beneficial to high-density integration of a fiber core structure in a multi-core optical fiber, has a large mode field area and a high-order mode rejection ratio, and gives consideration to both high power and high light beam quality.

The invention discloses a laser welding method for a copper-aluminum composite material, which comprises the following steps of: performing upsetting thinning treatment on a three-layer sandwich structure base material to ensure that the total thickness of a welding area is 1.5 mm, the thickness of an aluminum layer is 0.9-1.1 mm (the deformation rate is 10-30%), the thickness of a copper layer is 0.2-0.3 mm, the surface roughness Ra is less than or equal to 1.6 mu m, and the surface roughness Ra of an oxide layer is less than or equal to 5 mu m; a 1064nm optical fiber laser is adopted, welding is conducted at the power of 85%-95%, the speed of 120-150 mm / s and the frequency of 4000-6000 Hz, the fusion depth is 0.3-0.6 mm, and the fusion width is 1.2-2.0 mm. By means of the method, the tensile strength of the connector can be larger than or equal to 110 MPa, the resistivity is smaller than or equal to 2.5 * 10 <-8 > omega.m, the problems that traditional welding strength is low and conductivity is poor are solved, batch quality consistency is ensured, and the method is suitable for the fields of new energy automobiles and the like.

The invention discloses a high-efficiency erbium-ytterbium co-doped fiber laser for long-wavelength peak shifting pumping. The laser is characterized in that pump light enters an active fiber through a pump coupling device; the active optical fiber is doped with erbium ions and ytterbium ions, part of the pump light entering the active optical fiber is absorbed by the ytterbium ions, and part of the pump light entering the active optical fiber is absorbed by the erbium ions; ytterbium ions are transited from a ground state 2F7 / 2 to an excited state 2F5 / 2 energy level, cross relaxation occurs between the ytterbium ions and ground state erbium ions nearby the ytterbium ions, energy is transferred to the erbium ions, and the erbium ions are relaxed to a 4I13 / 2 energy level after transition from 4I15 / 2 to 4I11 / 2 is completed; erbium ions absorb pump light, transition from a ground state 4I15 / 2 to a 4I11 / 2 energy level and then relaxation to a 4I13 / 2 energy level are carried out, the erbium ions of the 4I13 / 2 energy level generate laser gain of 1.5 microns, and when the gain exceeds loss of a laser resonant cavity formed by the first resonant cavity feedback device and the second resonant cavity feedback device, 1.5 microns-band laser oscillation is formed and is output through the second resonant cavity feedback device. The influence of amplified spontaneous emission of ytterbium ions and excited state absorption of erbium ions on the efficiency of the laser is weakened, and the efficiency of the laser is improved.

Disclosed in the present invention is a near-infrared wavelength scanning pulse fiber laser having a low mode-locking threshold. According to the present invention, a nonlinear amplifying loop mirror and a saturable absorber mirror architecture are used to achieve a low mode-locking threshold and ensure long-term mode-locking stability. After mode-locking self-starting, an automatic control module automatically achieves single-pulse operation by adjusting the intensity of retro-reflected pulses. In the single-pulse operation stage, different frequencies of radio frequency signals and different signal intensities are provided for an acousto-optic tunable filter by means of a radio frequency module to achieve a 1030 nm-1100 nm wavelength scanning and tuning range.

The invention belongs to the technical field of laser wire stripping machines, and particularly discloses a deflection type double-head laser wire stripping machine which comprises a first machine frame and a second machine frame, the second machine frame is arranged on one side of the first machine frame, a cutting mechanism is arranged on the inner side of the first machine frame, and a placing table is fixedly connected to the top of the second machine frame; the cutting assembly is arranged, the double-laser-source modules adopt beam splitter prisms or double independent optical fiber lasers, CO2 laser and optical fiber double-waveband combination is supported, different insulation and metal materials are adapted, a driving motor is used for driving a rotating shaft to drive a connecting rod to rotate, and the two double-laser-source modules are driven to rotate by + / -30 degrees through mechanical deflection to reduce cutting dead angles. And the CCD measuring module is used for detecting the outer diameter of the wire rod and feeding back the detection result to a console, so that a worker can conveniently adjust the rotating angle of the double-laser-source modules, the cutting effect is improved, and the machining efficiency can be effectively improved through synchronous operation of the two double-laser-source modules.

The invention provides a pulse laser frequency control device and method, and belongs to the technical field of pulse fiber lasers. Comprising a frequency measurement module used for acquiring the frequency of a first external control signal; the frequency selection and frequency division module generates and outputs a seed frequency signal and a frequency division coefficient according to the frequency of the first external control signal obtained by the frequency measurement module; the frequency generation module is used for receiving the seed frequency signal output by the frequency selection and division module and outputting a seed frequency trigger signal; the pulse generation module is used for acquiring the seed frequency trigger signal output by the frequency generation module and providing a seed pulse signal for the seed driver, and the seed driver outputs pulse light according to the input seed pulse signal; the current control module is used for receiving a second external control signal and providing a current driving signal for each pump driver; and the RAM controller is used for receiving a third external control signal and the frequency division coefficient output by the frequency selection and frequency division module, and controlling the acousto-optic modulator to work.

The invention relates to a planning method, device and equipment for treating brain glioma through multi-fiber laser ablation. The method comprises the following steps: according to pre-acquired image information of a target patient and a segmentation result of a tumor region, sequentially performing segmentation sampling processing on the image information to obtain a candidate optical fiber path set; screening the candidate optical fiber path set according to an optical fiber planning objective function and an optical fiber planning constraint condition to obtain an intermediate optical fiber path set, and determining the number of optical fibers required by tumor ablation according to the intermediate optical fiber path set; determining a target optical fiber path set from the intermediate optical fiber path set according to the number of optical fibers required by tumor ablation and a predetermined path evaluation score; the target optical fiber path set at least comprises position information corresponding to each target optical fiber path. The method can improve the tumor ablation rate and reduce the use of optical fibers.

The invention discloses an optical fiber laser pipe cutting machine and an operation method.The optical fiber laser pipe cutting machine comprises a machine body, a first chuck, a second chuck and a laser cutting mechanism are installed on the machine body, and the first chuck and the second chuck are used for clamping a pipe and can drive the pipe to rotate; the machine body is fixedly connected with a pair of sliding rails matched with the first chucks, the straightening machine further comprises a fixing box, a plurality of straightening mechanisms and a force eliminating mechanism, each straightening mechanism comprises a plurality of hydraulic cylinders, the hydraulic cylinders are circumferentially and evenly fixed to the inner wall of the fixing box, and piston rods of the hydraulic cylinders are fixedly connected with pressure bearing parts. According to the optical fiber laser pipe cutting machine and the operation method, bent circular pipes can be pressed to be straight, the rejection rate is reduced, the pipes can be prevented from colliding with the laser cutting mechanism, the maintenance cost is reduced, meanwhile, the stress of the pipes can be eliminated, the pipes are prevented from being bent in the cutting process, and the cutting quality is guaranteed.

A DFB linear polarization single-frequency fiber laser based on the polarization traction effect comprises a polarization-maintaining single-axis fiber isolator, the input end of the polarization-maintaining single-axis fiber isolator is connected with the signal end of a polarization-maintaining wavelength division multiplexer, and the pumping end of the polarization-maintaining wavelength division multiplexer is connected with the output end of a single-mode pumping light source. A common end of the polarization-maintaining wavelength division multiplexer is connected with one end of the polarization-maintaining fiber bragg grating, the other end of the polarization-maintaining fiber bragg grating is connected with an output end of the phase-shift fiber bragg grating through the PZT phase modulator, and the phase-shift fiber bragg grating is inscribed on a gain fiber to form a DFB fiber laser resonant cavity and fixedly packaged in an automatic temperature control heat sink. The DFB fiber laser resonant cavity is connected with the input end of the photoelectric detector, and the photoelectric detector converts an idle end laser signal of the DFB fiber laser resonant cavity into an electric signal. The linear polarization single-frequency laser source with excellent performance, high linear polarization degree and high stability can be provided for the fields of fiber-optic gyroscopes, nonlinear frequency conversion, coherent polarization beam combination and the like.

A portable air-cooled fiber laser device disclosed by the present invention comprises a box body, a laser pumping source, a fiber output assembly, a power supply assembly, a heat dissipation engine and a control circuit are integrated in the box body, the power supply assembly adopts a drawable structure, a replaceable battery is arranged in the power supply assembly, and energy supply without an external power supply is realized. The heat dissipation engine is arranged in a sandwich type structure and is composed of a heat dissipation fin set and heat pipes embedded in the heat dissipation fin set, a transverse ventilation heat dissipation channel is formed through a heat dissipation fan, and efficient heat management is achieved. Connection with a mobile terminal or computer equipment in a wired or wireless mode is supported, and remote control over the operation state of the laser is achieved. The device is compact in structure, efficient in heat dissipation and convenient to carry, has good heat dissipation performance, independent power supply capacity and environmental adaptability, is suitable for application scenes such as multi-scene field operation and emergency use, and has good practicability and popularization value.

A high-power single-frequency laser amplifier based on prepared YAG derivative optical fibers comprises a single-frequency optical fiber laser seed source, the output end of the single-frequency optical fiber laser seed source is connected with the input end of a first-stage pre-amplifier, and the output end of the first-stage pre-amplifier is connected with the input end of a second-stage pre-amplifier. The output end of the secondary preamplifier is connected with the input end of the high-power double-cladding circulator, and the output end of the high-power double-cladding circulator is connected with a signal light input port of the high-power pumping signal beam combiner. The output end of the high-power pumping signal beam combiner is connected with one end of a specially prepared large-mode-field low-NA double-cladding rare earth doped YAG derivative optical fiber, and the other end of the large-mode-field low-NA double-cladding rare earth doped YAG derivative optical fiber is connected with the input end of the cladding light filter. The problem that expansion and diffusion of a fiber core in the YAG derived optical fiber are not controlled is solved, and therefore the theoretical power limit of single-frequency optical fiber laser amplification conducted through a silica optical fiber at present is broken through.

An apparatus includes a spectrometer receiving an optical input signal that includes an input optical spectrum. The spectrometer includes a fiber laser cavity pumped by a first optical replica of the optical input signal that generates stimulated Brillouin scattering traveling in a direction opposite to a direction of the optical input signal. The first optical replica of the optical input signal excites at least one lasing mode in the fiber laser cavity. The at least one lasing mode respectively includes at least one lasing mode frequency. The at least one lasing mode frequency is offset by a respective Brillouin frequency shift from the respective at least one input frequency. The spectrometer also includes an optical heterodyne receiver. The optical heterodyne receiver generates the electrical output signal. The spectrometer outputs a measurement of the input optical spectrum based on the respective Brillouin frequency shift and the at least one input frequency.