42 results about "Random laser" patented technology

The electro-absorption modulated laser comprises a substrate, a buffer layer, a lower waveguide layer, an active layer region, an upper waveguide layer and a cover layer from bottom to top in sequence, electromagnetic isolation regions are formed in the upper waveguide layer and the cover layer, and a DFB laser and an EAM modulator are formed on the two sides of each electromagnetic isolation region respectively; a grating layer is arranged in an upper waveguide layer of the DFB laser, one end of the grating layer extends to an electromagnetic isolation area, a waveguide area is arranged between the other end of the grating layer and the end of the DFB laser in a spaced mode, in the preparation process, the coupling butt joint face of the DFB laser and the EAM modulator is etched, and then a passive InGaAsP body material is grown for the second time; compared with a traditional electro-absorption modulated laser, the problem of grating random truncation caused during cleavage is solved in a DFB laser area, so that generation of laser random phases is avoided; optimization design is carried out on a butt joint coupling interface, so that the tidiness of the butt joint interface is improved, and the phenomenon of light scattering caused by an uneven interface is avoided; therefore, the laser has better structural characteristics, the yield of the laser is improved, the beam quality of the laser is improved, and the transmission distance of the laser is prolonged.

The utility model provides an adjustable random laser sample clamp which comprises a supporting frame, an adjusting frame and two sliding seats movably installed on the adjusting frame, the adjusting frame is rotatably installed on the supporting frame, an adjusting mechanism is arranged on the supporting frame, folded plates are rotatably arranged on the sliding seats, the middle portions of the folded plates are rotatably connected with the sliding seats, and the middle portions of the folded plates are rotatably connected with the sliding seats. The fixing plates, the elastic pieces and the fasteners are arranged on the sliding seats, the cushion blocks are detachably arranged on the fixing plates, when the sample clamping device is used, the two sliding seats can be fixed through the fasteners so that the distance between the two sliding seats can be adjusted according to the length of a sample, and the sample clamping device is suitable for clamping samples of different lengths; the elastic piece acts on the folded plate to drive one end of the folded plate to elastically abut against the cushion block to clamp a sample, the cushion blocks of different sizes can be replaced to adjust the clamping force between the folded plate and the cushion block, and the angle position of the adjusting frame can be adjusted through the adjusting mechanism according to needs so as to adjust the angle position of the sample. Experimental operation is facilitated, and experimental requirements are met.

The utility model provides a random laser experiment mounting rack with a sleeve structure, which comprises a rack body, a mounting table, an objective table, a clamping assembly, an adjusting assembly, a shading cylinder and an adjusting disc, the side surface of the shading cylinder is provided with an entrance port and an exit port, the adjusting disc is rotatably arranged on one side of the shading cylinder, a plurality of lenses are detachably arranged on the adjusting disc, and the lenses are fixed on the rack body. A sample is fixed to the objective table through the clamping assembly, the whole sample is covered with the shading cylinder, laser irradiates the sample from the incident port and is emitted out from the emergent port, most of light is shaded through the shading cylinder, light pollution is reduced, the position, irradiated by the laser, of the sample can be adjusted by adjusting the position of the objective table through the adjusting assembly, and experimental research is facilitated; and the different lenses are driven to be aligned with the emergent ports by rotating the adjusting disc, so that the light rays can be researched at different refraction angles, the operation is simple, and various experiment requirements can be met.

The invention belongs to the technical field of optical fiber lasers, and particularly relates to a random laser based on a biconical optical fiber and a multi-wavelength laser output method. The random laser based on the single-mode biconical optical fiber comprises an optical fiber reflector, a biconical optical fiber, an optical fiber coupler, a wavelength division multiplexer, an erbium-doped optical fiber, an optical fiber random Rayleigh scattering feedback unit and an optical fiber 8-degree chamfer which are connected in sequence. A signal light port of the wavelength division multiplexer is connected with an input port of the optical fiber coupler, a public port of the wavelength division multiplexer is connected with an input port of the erbium-doped optical fiber, and a pump light port of the wavelength division multiplexer is connected with an output port of the 980nm laser. According to the invention, multi-wavelength selection in the random laser is realized by using the comb filtering function of the biconical fiber; random Rayleigh scattering in the optical fiber random Rayleigh scattering feedback unit is used as optical feedback, and the random Rayleigh scattering feedback unit and the reflector form a laser cavity. And multi-wavelength laser output is formed.

The invention relates to an interference type encryption sensing method and system based on random laser, and is applied to the field of fiber lasers, and the method comprises the steps: carrying out the beam splitting of pump light generated by a pump light source, obtaining a first pump light beam and a second pump light beam, injecting the first pump light beam into an annular cavity, and generating random laser; splitting the random laser to obtain a first random laser beam and a second random laser beam; emitting the first random laser beam to the surface of a target, and generating a Doppler frequency shift signal according to reflected light reflected by the target and the first random laser beam; mixing the second random laser beam with the second pump light beam to generate a beat frequency signal, and converting the beat frequency signal into a corresponding electric signal; processing the electric signal through a spectrum analyzer and outputting a true random number; and carrying out algorithm processing on the true random number and the Doppler frequency shift signal to generate a ciphertext, and transmitting the ciphertext to a preset receiving end. The technical effect of the application is that the randomness of the ciphertext and the security of data transmission are improved.

The invention relates to a deep blue light random fiber laser based on a femtosecond active phase shift fiber grating, and relates to the technical field of laser. Comprising a 900nm random laser seed light source, a collimator, a first plano-convex lens, a frequency doubling crystal, a temperature control platform, a second plano-convex lens and a beam splitter prism, 900nm random laser enters the collimator; a light beam enters the frequency doubling crystal, the frequency doubling crystal efficiently absorbs 900nm wave band random laser through the CuFe2O4 metal nanoparticle film, and the output end face is plated with a 450nm anti-reflection film; the first plano-convex lens and the second plano-convex lens enable the optimal focusing waist spot of 900nm random laser to be at the central position of the frequency doubling crystal; 900 nm and 450 nm random laser is collimated through a second plano-convex lens, the 900 nm random laser is separated through a beam splitter prism, and 450 nm deep blue light random laser output is obtained. According to the invention, blue light random laser output with high stability, low phase noise and low coherence is obtained.

The invention discloses a compact tunable narrow-linewidth fiber laser light source, and belongs to the field of fiber lasers. The structure comprises a Brillouin pump and a Brillouin semi-open annular random fiber cavity. The Brillouin pump adopts a tunable laser and provides pump light for the Brillouin semi-open annular random optical fiber cavity. The erbium-doped optical fiber in the cavity serves as a nonlinear Brillouin gain medium and a linear gain medium at the same time, the narrowband gain of Stokes light is achieved through the stimulated Brillouin scattering effect in the optical fiber, laser output of different wavelengths can be achieved by adjusting the wavelength of Brillouin pump light and matching the center wavelength of the tunable filter, and the laser output of different wavelengths can be achieved. Random distributed feedback is introduced through the random fiber bragg grating to form random laser oscillation, the cavity length is greatly shortened, the line width is deeply compressed, and ultra-narrow line width tunable laser output is achieved while it is guaranteed that the structure of the laser light source is compact. According to the invention, the application of the tunable narrow linewidth laser in the aspects of optical fiber communication, biomedical imaging and the like is expanded.

An optical fiber sensor capable of simultaneously measuring temperature and strain belongs to the field of optical fiber sensing technology and is composed of a pump source, a wavelength division multiplexer, a 3-dB coupler, a polarization-maintaining optical fiber, an optical fiber grating, a fixed base, a translation stage, an erbium-doped optical fiber wound between the fixed base and the translation stage, a 10:90 optical coupler, and a random grating. The present invention utilizes erbium-doped optical fiber to provide optical gain, and through laser pumping by a pump source, Er 3+ It absorbs pump light and generates stimulated radiation. After reaching the output laser threshold, it generates random laser output. The Sagnac loop structure and fiber Bragg grating are used as temperature sensors, and the erbium-doped fiber winding device is used as a strain sensor. By detecting the wavelength and intensity changes of the output light, the temperature and strain can be measured simultaneously. It has the characteristics of simple manufacturing process, low cost, high sensitivity, etc., and can perform sensing measurements on different ring mirrors.

The application belongs to the technical field of laser, and relates to a method for manufacturing a PVA / dye flexible random laser based on an electrostatic spinning method. A mixed solution of PVA, ovalbumin, rhodamine dye and Au nano-particles is adopted, the sample size and the morphology of the spinning structure are controlled by controlling the voltage, the spraying distance and the needle tip size in the electrostatic spinning technology process, and then the wavelength and the mode of laser emission and other parameters are adjusted. The design is simple and intuitive, the method is flexible and convenient, the principle is reliable, and the method is easy to realize. The obtained flexible random laser is easy to be coupled with other photon devices, and the quantitative control of the laser property is easy to be realized.

The invention discloses a 3μm fiber laser based on fluoride-doped phase-shift grating feedback, which belongs to the technical field of fiber lasers. The invention comprises an LD pumped laser source group, a fiber beam combiner, an optical isolator, a fiber grating, a first high-germanium-doped fiber, a second high-germanium-doped fiber and a double-cladding Ho-doped fiber engraved with a random phase-shift grating. 3+ The present invention is composed of a double cladding doped with Ho 3+ Random phase-shifted gratings are written on fluoride optical fibers and pumped by a pump source laser. 3+ It absorbs pump light and generates stimulated radiation. When the output laser threshold is reached, random laser output is generated. The pump laser oscillates back and forth through the fiber grating reflection, which can effectively reduce the pump threshold power and improve the pump efficiency. The laser has the characteristics of low threshold power, high conversion efficiency, compact structure, and all-fiber.

The application relates to a deep blue random fiber laser based on a femtosecond active phase shift fiber grating and relates to the technical field of lasers. The application comprises a 900nm random laser seed light source, a collimator, a first plano-convex lens, a frequency doubling crystal, a temperature control platform, a second plano-convex lens and a beam splitter prism; the 900nm random laser enters the collimator; the light beam is incident into the frequency doubling crystal, the frequency doubling crystal is high-efficiency absorbed to the 900nm waveband random laser through a CuFe2O4 metal nanoparticle film, and the output end face is coated with a 450nm antireflection film; the first plano-convex lens and the second plano-convex lens make the optimal focusing waist spot of the 900nm random laser be at the center position of the frequency doubling crystal; the 900nm and 450nm random lasers are collimated through the second plano-convex lens, the 900nm random laser is separated through the beam splitter prism, and the 450nm deep blue random laser output is obtained. The application obtains the blue random laser output with high stability, low phase noise and low coherence.

An ultra-long distance transmission conductor state monitoring system comprises a demodulator, an optical fiber type stress sensor, an optical fiber type wind speed sensor, an optical fiber type meteorological sensor and a sensing conductor. Wherein various sensors and sensing wires are connected with a demodulator through sensing optical fibers in the sensing wires, so that data acquisition, signal transmission and analysis, anti-interference guarantee and remote monitoring support are realized; the demodulator comprises a broadband light source, a first erbium-doped fiber amplifier, an acousto-optic modulator, a circulator, a low-noise random laser emission module, an ultra-weak reflection fiber grating, a long-distance transmission fiber and an EDF which are connected in sequence; the acousto-optic modulator is connected with the acousto-optic modulator driver; the circulator, the second erbium-doped fiber amplifier, the attenuator, the fiber bragg grating demodulation module and the upper computer are sequentially connected in series. According to the invention, the technical blank is filled, the signal transmission distance is long, the environmental adaptability is good, maintenance is avoided, and the comprehensive technical effect is excellent.

The application discloses a wavelength-tunable visible light system based on a random fiber laser, which comprises a random fiber laser module, a first isolator, a fiber amplifier module, a second isolator, a dual-wavelength tunable Raman random laser module, a third isolator and a nonlinear frequency conversion module which are sequentially connected. The random fiber laser module is used for outputting tunable wavelength ytterbium-doped random laser. The fiber amplifier module is used for amplifying the optical power of the ytterbium-doped random laser to obtain amplified ytterbium-doped random laser. The dual-wavelength tunable Raman random laser module is used for outputting dual-wavelength tunable Raman random laser. The nonlinear frequency conversion module is used for converting the dual-wavelength tunable Raman random laser into tunable visible light random laser. The application can realize the output of wavelength-tunable visible light random laser, and there is no gap in the whole adjustment range.

The invention provides a public safety patrol system and method based on laser calibration visual obstacle avoidance. According to the public safety patrol system and method based on laser calibration visual obstacle avoidance, a non-coding, irregular and dynamically changeable random laser dot matrix is projected to a front environment; acquiring a scene image containing laser dot matrix light spots; inverting the particulate matter concentration and visibility score of the current environment based on a Mie scattering model; fusing the light spot deformation depth and the light spot visual depth to obtain space depth information of the obstacle; fitting the three-dimensional contour of the obstacle according to the space depth information of the obstacle, identifying the material category of the obstacle through a classifier, and generating a collision-free early warning profile and a real-time path based on the distance, contour and material information of the integrated obstacle and the position of the robot; according to the invention, obstacle perception can still be stably realized in scenes of no light, weak light, smog, dust and the like; the method has the advantages of low cost, high robustness, high response speed, high material identification capability and the like, and can be widely applied to public scenes such as mine patrol and underground pipe gallery patrol.

A random fiber laser based on a random phase-shift grating includes an erbium-doped fiber amplifier, a saturable absorber, an optical isolator, an electro-optic modulator, an optical filter, a 10:90 optical coupler, a polarization controller, a broadband microwave source, a microwave isolator, a microwave circulator and a random phase-shift grating; wherein the random phase-shift grating is composed of an impedance discontinuity point, an outer cladding, an outer conductor, an inner cladding and an inner conductor, and the random phase-shift grating is an impedance discontinuity point obtained by mechanical processing on a coaxial cable. It is used as a new scattering medium in a random laser. The present invention uses a random microwave signal as a control signal to solve the problem of excessive light scattering medium loss and poor directivity in a random laser. The manufacturing process is simple and the parameters are less affected by environmental factors.

The present invention discloses a broadband high-order Raman fiber random laser, which includes a tunable ytterbium-doped fiber laser seed source, a diode pump source, a pump combiner, a ytterbium-doped fiber, a second optical fiber isolator, a first wavelength division multiplexer, a Raman fiber, a second wavelength division multiplexer, an optical fiber circulator, and a superluminescent light-emitting diode, which are connected in sequence; the tunable ytterbium-doped fiber laser seed source is used as a pump source for a cascaded Raman random laser after being amplified by the ytterbium-doped fiber, and a broadband fiber loop mirror and a first fiber bevel end face for laser output are connected to the first wavelength division multiplexer; the end face reflectivity of the first fiber bevel end face is adjustable; the superluminescent light-emitting diode is connected to the second wavelength division multiplexer through the optical fiber circulator; the present invention uses the tunable ytterbium-doped fiber laser to be power-amplified by the ytterbium-doped fiber amplifier to excite cascaded Raman random laser in the Raman fiber, injects the broadband seed backward, and adopts a fiber bevel end face with adjustable reflectivity at the output end to realize broadband high-order Raman random laser with low noise and controllable bandwidth, and solves the problems of large noise and difficult bandwidth regulation of high-order Raman random laser in the prior art.

The application belongs to the technical field of semiconductor lasers, and discloses an integrated chip, a manufacturing method of the integrated chip and a semiconductor random laser. The integrated chip comprises ring mirrors, the ring mirror comprises a ring mirror waveguide and a directional coupler, the two ends of the ring mirror waveguide are connected with the ports on the corresponding sides of the directional coupler, the number of the ring mirrors is set to be multiple, the multiple ring mirrors are connected in sequence to provide random feedback, two adjacent ring mirrors are connected through a connecting waveguide, and the ring mirror located at one end is connected with a light output waveguide on the side away from the adjacent ring mirror. The semiconductor random laser comprises the integrated chip, and further comprises a semiconductor optical amplifier, the semiconductor optical amplifier is connected with the light output waveguide of the integrated chip, and the output end of the semiconductor optical amplifier is provided with a reflection structure corresponding to the light output waveguide. The integrated chip provided by the application is used as the feedback structure of the semiconductor random laser, has the advantages of simple structure, high integration, and greater reflection bandwidth and higher feedback strength.

The present invention discloses a multi-wavelength random fiber laser based on an inclined parallel inscribed fiber grating array, belonging to the technical field of fiber lasers. It includes a pump light source, a fiber grating array, a grating axial stretching device, a wavelength division multiplexer, and a gain amplification unit. The pump light is coupled into the gain amplification unit through the wavelength division multiplexer to excite it, and the gain amplification unit amplifies the pump light source in the optical path. After the fiber grating array adjusts the strain through the grating axial stretching device to change its central wavelength, it provides the feedback of the gain light and wavelength selection. The gain light reflected by the fiber grating array is amplified in the gain amplification unit, and gradually forms a multi-wavelength random laser output as the power of the pump light source increases. The present invention uses an inclined parallel inscribed fiber grating array as both a multi-wavelength selection device and a high-reflection mirror at one end of the laser cavity, and uses a Raman fiber at the other end to provide Rayleigh scattering feedback, reducing the number of components constituting the laser and making the structure simpler.

The invention discloses a dissipative soliton resonance laser reverse design method based on machine learning, and the method comprises the steps: 1) building two groups of associated data sets which are respectively used for training an SVM and a BP neural network, the SVM is used for predicting the dissipative soliton resonance pulse convergence, and the BP neural network is used for predicting the output time domain and spectral waveform of a laser; (2) a PSO algorithm particle swarm is initialized, the position parameter of each particle corresponds to a set of random laser cavity parameters, an SVM model is input in advance, particles meeting the convergence condition are screened out, and the particles serve as an initial particle swarm again; 3) iteratively updating particle position information, inputting the particle position information into the BP neural network, and predicting pulse time domain and spectral waveform information; and when the mean square error of the predicted waveform and the set target waveform is lower than a set value, outputting a group of optimal laser cavity parameters to realize the reverse design of the laser. The problem that a dissipative soliton resonance fiber laser is difficult to design under the condition of low-absolute-value net cavity dispersion is effectively solved.

The invention discloses an encryption and decryption system and method based on random laser chaotic signal generation, a transmitting end, a first reflector, a first continuous wave laser, a first circulator and a first optical coupler of the system are connected in sequence, and a second continuous wave laser is connected with the first circulator to obtain a common optical chaotic signal; the first optical coupler divides a common optical chaotic signal into a plurality of beams, each beam of optical chaotic signal sequentially passes through a tunable optical filter, a tunable dispersion compensator and the like to obtain optical chaotic signals with different parameters, then the optical chaotic signals enter a first phase modulator, and the first phase modulator is connected with a first dispersion element; the first phase modulator is connected with a second phase modulator at a receiving end; in the receiving end, a second reflecting mirror, a third continuous wave laser, a second circulator and a second optical coupler are connected in sequence, and a fourth continuous wave laser is connected with the second circulator; the second optical coupler divides the public optical chaotic signal into a plurality of beams, each beam of optical signal sequentially passes through a tunable optical filter, a tunable dispersion compensator and the like and then enters a second phase modulator to obtain a random laser chaotic signal synchronous with a transmitting end, and the second phase modulator is connected with a second dispersion element.

The application provides a fiber vortex random laser integrated with multiple orbital angular momentum modes and a preparation method thereof, and a vortex random laser generating device and method, and belongs to the technical field of lasers; the problems of the existing vortex random laser, i.e., the radiation direction to be optimized and the system integration to be strengthened, are solved; the fiber vortex random laser integrated with multiple orbital angular momentum modes comprises a microfluid channel, a single-mode optical fiber, an optical fiber splitter and an optical fiber integrated with a spiral phase plate; a gain medium and scattering particles are arranged in the microfluid channel; one end of the single-mode optical fiber is fixed in the microfluid channel; the other end of the single-mode optical fiber is coupled with an end face of the spiral phase plate of the optical fiber integrated with the spiral phase plate through the optical fiber splitter; the spiral phase plates of different optical fibers integrated with the spiral phase plates carry different topological charges, and the vortex random lasers carrying different orbital angular momentum modes are formed; the application is applied to the random laser.

The invention relates to a random laser coherence dynamic information encryption device and a use method, to-be-encrypted information is converted into binary codes through binary coding, and digits in the binary codes correspond to voltage applied by a direct current power supply, so that the voltage applied to a random laser sample is controlled according to the binary codes; therefore, the spatial coherence and the light intensity of the emergent laser emitted by the random laser excitation device are changed, and the emergent laser corresponding to the binary code is output at the same time. After the emergent laser passes through the spatial coherence observation device and generates interference fringes, the emergent laser is transmitted to the spatial coherence analysis system to obtain binary codes corresponding to spatial coherence in the interference fringes, and then encrypted information is obtained based on the binary codes, so that the rapid, simple and convenient encryption, decryption and transmission process of the to-be-encrypted information is completed. And meanwhile, encryption can be carried out in combination with information such as wavelength and phase of laser, so that the encryption flexibility of the laser is improved.

The invention relates to the technical field of photothermal effect detection, and provides a graphene photothermal effect and motion detection device and method.The graphene photothermal effect and motion detection device comprises a pulse laser, a laser energy and polarization regulation and control device, a beam splitter, a convex lens, a fiber optic spectrometer and a camera device which are sequentially arranged; the beam splitter is also connected with an energy meter; the optical fiber spectrometer is used for collecting a random laser spectrum obtained after the pulse laser irradiates the graphene sample; the camera device is used for collecting an image of the graphene sample; fusing the spectrum change acquired based on the optical fiber spectrometer, the sample image acquired by the camera device and the energy of the random spectrum acquired by the energy meter to obtain a detection result of the graphene sample. Based on fusion analysis of spectral data, incident light energy and a sample dynamic image, the photothermal response characteristics and motion characteristics of the graphene sample can be comprehensively evaluated from multiple angles, the limitation of a single detection means is overcome, and the accuracy, comprehensiveness and reliability of a detection result are remarkably improved.

The invention discloses an optical fiber random laser speckle-free illumination method based on a disordered disturbance multimode optical fiber, which relates to the field of laser illumination imaging and comprises a pumping source, a reflector, a first wavelength division multiplexer, a high-nonlinearity optical fiber, a second wavelength division multiplexer, an isolator, an attenuator, a multimode optical fiber, a signal generator and a multimode optical fiber disturbance device. And three effect verification assemblies including a lens, ground glass and an infrared camera. Pump light is injected into the optical fiber link through the first wavelength division multiplexer, the multi-mode optical fiber is arranged in the multi-mode optical fiber disturbance device, a driving power supply is provided for a piezoelectric ceramic piece in the multi-mode optical fiber disturbance device through the signal generator, and other components are sequentially connected end to end. According to the built optical fiber random laser, Rayleigh scattering of a high-nonlinearity optical fiber and a reflector are adopted for providing optical feedback, time and space disordered disturbance is applied to laser in a multimode optical fiber through a piezoelectric ceramic piece, space coherence is reduced, and the laser serves as an illumination light source for speckle-free imaging after being collimated.

The invention discloses an automobile lamp light-emitting structure and a manufacturing method thereof, and belongs to the technical field of automobile lamp manufacturing. The automobile lamp light-emitting structure comprises a double-color decoration frame, a PCBA fixing support and a PCBA plate; the double-color decoration frame comprises a black light blocking part and a red light transmitting part, and an LED lamp and a driving circuit are arranged on the PCBA board; the double-color decoration frame and the PCBA fixing support are fixed in a clamping mode, and the PCBA board is fixedly connected with the PCBA fixing support in a hot riveting mode. According to the invention, the nanoscale indium-tin alloy metal coating and the random laser etching pattern are arranged, and meanwhile, the thickness of the coating is controlled, so that the bright effect of'starry sky flickering 'is realized; the optical efficiency is improved through the concave-convex texture of the optical structure, and other optical components do not need to be developed.

The invention discloses a random microlens array and a manufacturing method thereof, and belongs to the technical field of semiconductor device manufacturing processes. Aiming at the problems that the structure is not real and random, the template dependence is strong, the morphology is difficult to continuously regulate and control, the process is complicated, the efficiency is low and the random micro-lens array is not suitable for large-area processing in the existing random micro-lens array preparation method, laser of an ultraviolet wave band is irradiated to the surface of a diffuser by utilizing a laser speckle gray scale photoetching system; forming a laser speckle pattern with statistical randomness, taking the intensity distribution of the laser speckle pattern as a natural gray level mask, and transferring the intensity distribution to the photoresist on the surface of the transparent substrate in a gray level exposure mode to form a three-dimensional free-form surface micro-lens morphology which is arranged in a non-periodic manner and has continuous change; therefore, a random micro-lens array preparation scheme which is real and random in structure, adjustable in height, free of a template and simple in process is realized.

The application discloses a double-pump cascade type super-narrow linewidth Brillouin random laser, which comprises a pump laser, a fiber amplifier, an optical isolator, a fiber coupler, a first fiber circulator, a second fiber circulator, a third fiber circulator, an adjustable fiber attenuator, a first Brillouin gain fiber, a second Brillouin gain fiber and a tunable filter; the application adopts two optical fibers which are subjected to stimulated Brillouin scattering frequency shift superposition, stimulated Brillouin scattering occurs in the first Brillouin gain fiber, Stokes light generated by the first Brillouin gain fiber is further provided with a Stokes light signal source for the second Brillouin gain fiber after passing through the adjustable fiber attenuator, meanwhile, Rayleigh scattering occurs in the second Brillouin gain fiber and provides random feedback for the first Brillouin gain fiber after passing through the third fiber circulator; in the system, higher Brillouin gain is realized, laser linewidth can be further compressed, and finally super-narrow linewidth random laser is output.

The present invention discloses a method for reverse design of a dissipative soliton resonant laser based on machine learning. The method comprises the following steps: 1) establishing two sets of associated data sets, one for training an SVM and the other for training a BP neural network. The SVM is used to predict the convergence of the dissipative soliton resonant pulse, and the other for predicting the laser output time domain and spectral waveform. 2) initializing a PSO algorithm particle swarm, with each particle's position parameter corresponding to a set of random laser cavity parameters. The SVM model is pre-input to filter out particles that meet the convergence criteria and reuse them as the initial particle swarm. 3) Iteratively updating the particle position information and inputting it into the BP neural network to predict the pulse time domain and spectral waveform information. When the mean square error between the predicted waveform and the set target waveform is lower than a set value, a set of optimal laser cavity parameters is output, thus achieving laser reverse design. The present invention effectively solves the problem of difficult design of dissipative soliton resonant fiber lasers under conditions of low absolute net cavity dispersion.

This invention relates to the field of organic photonics and laser device technology, specifically disclosing a laser based on a mesoporous titanium dioxide substrate and its fabrication method. The laser comprises a transparent substrate, a mesoporous titanium dioxide thin film on the substrate, and an organic conjugated polymer gain medium layer on the titanium dioxide thin film. The mesoporous titanium dioxide layer is fabricated by spraying or spin coating, utilizing its disordered porous structure to provide light scattering feedback. Low-threshold random laser emission can be achieved under optical pumping without the need for a traditional precision resonant cavity. This device features a simple structure, low fabrication cost, good process compatibility, and applicability to polymer gain media with various emission wavelengths, providing a new technical path for realizing low-cost, easily integrated electrically pumped organic lasers.

The present invention provides a supercontinuum light source based on random laser, which includes a pump source, a beam combiner, a gain fiber, a first long-distance single-mode communication fiber, a total output end, and a random laser reflection module. The first long-distance single-mode communication fiber is used to generate supercontinuum fiber laser, and the random laser reflection module is used to reduce the threshold of random laser. The output end of the pump source and the output end of the random laser reflection module are both connected to the input end of the beam combiner. The output end of the beam combiner, the gain fiber, the first long-distance single-mode communication fiber, and the total output end are connected in sequence. The supercontinuum spectrum is generated based on the fiber random laser technology, with a simple and reliable structure, and it can effectively avoid the loss of the supercontinuum light source during fiber transmission. By using the first long-distance single-mode communication fiber, it has good compatibility and excellent beam quality. The lasing threshold of the random laser is reduced through the random laser reflection module, the supercontinuum threshold is reduced, and the practicability is enhanced.