55 results about "Nonlinear absorption" patented technology

The invention provides a femtosecond laser flexible transmission device based on a hollow-core optical fiber, which comprises a first reflector assembly, a light convergence assembly and a second reflector assembly, a beam expanding collimating lens group is arranged between the second reflector assembly and the light convergence assembly, the femtosecond laser flexible transmission device is also provided with an optical cable, the hollow-core optical fiber is arranged in the optical cable, and the two ends of the optical cable are provided with optical fiber coupling ends. According to the femtosecond laser flexible transmission device, the problem of femtosecond laser flexible transmission is solved, the structure can be conveniently optimized, and the problems of nonlinear absorption, pulse width expansion and the like of laser can be solved through vacuumizing.

The invention provides a modification processing method and processing system based on beam shaping, and the method comprises the following steps: obtaining three-dimensional light field distribution corresponding to a three-dimensional model through a holographic algorithm according to the three-dimensional model of a target modification structure, and generating a phase modulation diagram; loading the phase modulation diagram through a spatial light modulator, and modulating the wavefront phase of the incident laser, so that a light beam is focused on the surface of the material or in the material to form a preset spatial curved surface light field; and the spatial curved surface light field is focused on the material, so that the material in the light field region is subjected to nonlinear absorption or phase change, and a modified structure of a three-dimensional model is directly formed. According to the method, the limitation of traditional point-by-point scanning type machining is broken through, the machining efficiency and flexibility of a complex three-dimensional structure are remarkably improved, the method is suitable for scenes such as transparent material internal waveguide inscribing, curved surface splinter separation, large-area stripping, functionalized surface preparation and opaque material huge removal machining, and the machining efficiency and quality are remarkably improved.

A ring resonator (10) and a NALM (20) configured as a saturable absorption mechanism constitute a laser oscillator. A multiport BPF (12) is provided to a path through which light propagates in the laser oscillator, the multiport BPF (12) passing light in a prescribed band of the propagating light, and branching light outside of the prescribed band as monitoring light (L). A photodetector (1) detects the monitoring light (L). A control unit (2) controls the oscillation state of the light propagating through the laser oscillator on the basis of the intensity of the monitoring light (L), thereby controlling the mode synchronization of the light propagating through the laser oscillator.

The invention discloses a super-diffraction dark spot microscopic imaging method based on nonlinear focal spot competition. The hollow light beams with different wavelengths are subjected to incoherent overlapping in a focus area, the double hollow light beams generate excitation photon nonlinear absorption competition in a fluorophore peripheral overlapping area, super-diffraction dark spots are finally generated in a focal plane, and stable fluorescence signals are formed in a small-size signal detection area. A target signal is extracted through a weak signal locking amplification technology. The optical diffraction limit is broken through, so that high-precision positioning of the to-be-observed object in the diffraction limit area becomes possible. The optical power needed by the system is low, the detection sensitivity is high, the device structure is simple, and the system is suitable for high-resolution observation in the fields of biomedicine, nano materials and the like.

The invention discloses a femtosecond laser direct writing method based on speed self-adaption, which comprises the following steps: acquiring processing parameters and processing requirements, and controlling a motion platform to calibrate a to-be-processed sample to obtain a plurality of speed nodes on a laser processing path; performing interpolation and smoothing processing on the plurality of speed nodes to obtain a speed curve; discrete sampling is carried out on the speed curve according to the self-adaptive machining intervals, and the scanning speed in each machining interval is determined; and based on the scanning speed in each processing interval, controlling the motion platform to carry out femtosecond laser direct writing so as to realize femtosecond laser direct writing of optical waveguide, multi-photon polymerization, domain inversion, surface removal or nano transfer printing. And by controlling the scanning speed of each self-adaptive interval in the machining process, the energy of nonlinear absorption deposition is controlled, so that the machined structure is controllable. The scanning speed in the machining process can be controlled, control is flexible, the control frequency is high, and continuous control over the machining structure is achieved through large-range speed change.

The present application relates to a kind of pyridyl perovskite nanocrystal materials and its preparation and application, using PyMA as surface ligand, through the amino group on PyMA and the defect site on perovskite inorganic lattice Effective coordination bond is prepared to obtain new perovskite nanocrystal material.Compared with prior art, the nanocrystal material of the present application shows significantly enhanced nonlinear optical absorption performance in ultrafast femtosecond laser, different waveband region, which is due to the introduction of PyMA surface ligand, passivates the defect site in perovskite nanocrystal, improves the stability of perovskite nanocrystal structure.In addition, the aromatic structure of PyMA, promotes the regular arrangement of ligand on the surface of perovskite nanocrystal, improves the conductivity, enhances the electronic coupling between nanocrystal.Two kinds of factors synergistically endow the target material with excellent nonlinear absorption performance.

The present application belongs to the field of numerical simulation of the interaction between laser and matter, and in particular, relates to a method for numerical simulation of composite laser ablation. The method uses finite element software to establish a basic model for numerical simulation of the interaction between continuous laser and matter, and treats the change in the absorption rate of the material to the continuous laser due to manufacturing defects on the surface of the ultrafast laser ablation as equivalent to nonlinear absorption, so as to simulate the absorption coefficient change process formed by manufacturing defects on the surface of the ultrafast laser ablation material; uses spectral detection combined with Sedov-Taylor theory to construct a pressure calculation model for ultrafast laser-excited plasma shock waves, adds plasma shock wave pressure to the basic model for numerical simulation of the interaction between continuous laser and matter with the corresponding absorption coefficient, and establishes a numerical model of the ablation process of continuous-ultrafast composite laser, so as to analyze the change process of the composite laser ablation molten pool, and the influence of ultrafast laser pulse shock wave pressure on the sputtering and temperature change of the molten pool.

The invention belongs to the technical field of lasers, and particularly relates to a saturable absorber based on liquid metal and a regulation and control method thereof.The saturable absorber comprises an optical fiber, a first two-dimensional material layer and a liquid metal layer; the first two-dimensional material layer is arranged on the end face of the optical fiber, and the liquid metal layer is arranged on the first two-dimensional material layer. By introducing the combination of the liquid metal and the first two-dimensional material layer, the comprehensive advantages of high dynamic adjustability, nonlinear absorption enhancement, efficient fiber integration, intelligent electromagnetic regulation and control and interface stability improvement are realized, and a new technical scheme is provided for a high-performance ultrafast laser and a tunable photonic device.

The invention provides Nd-doped molybdenum disulfide with adjustable near-infrared nonlinear absorption and a preparation method of the Nd-doped molybdenum disulfide, belongs to the technical field of nano materials, and aims to solve the technical problem of poor near-infrared photoelectric property of MoS2. The preparation method of the Nd-doped molybdenum disulfide comprises the following steps: dissolving a molybdenum source, a sulfur source, a neodymium source and a reducing agent into a solvent to prepare a reaction solution, and performing solvothermal reaction to prepare the Nd-doped molybdenum disulfide nano material. The prepared MoS2 nanosheet is rich in VS, and the band gap of the MoS2 nanosheet is reduced to 0.75 eV and is obviously lower than the standard band gap (1.28-1.98 eV) of intrinsic MoS2, so that the nonlinear optical response at the wavelength of 1064 nm is successfully realized, the SA effect is shown, and the MoS2 nanosheet can be applied to devices such as a saturable absorber, an optical switch and a laser mode locker. Furthermore, by introducing Nd < 3 + > for doping, controllable conversion of nonlinear absorption behavior from SA to RSA along with light intensity change is realized.

The invention relates to the field of laser processing, in particular to a glass three-dimensional curved surface femtosecond laser welding method based on space-time focusing and multi-physics field coupling. Comprising the following steps: combining multiple beams of femtosecond laser, infrared laser and ultraviolet laser, regulating and controlling through a synchronous space-time focusing system, coaxially combining the beams to one light path in space, respectively focusing at the joints of the three-dimensional curved surface of the glass, and realizing initial melting by utilizing nonlinear absorption induced by the femtosecond laser, infrared laser enhances heating and fusion depth control, and ultraviolet laser performs nanometer remelting treatment on the edge of a welding seam, so that the welding compactness and the bonding strength are improved; in the infrared laser welding process, low-frequency ultrasonic waves are introduced to regulate and control a molten pool microstructure and release residual stress, wavefront regulation and control, an AI module and interference feedback are matched, high-stability closed-loop welding control under the synergistic effect of multiple physical fields is achieved, and the glass welding efficiency, adaptability and welding quality are remarkably improved.

A method for writing a desired phase change pattern in an optical polymeric material includes generating at least one pulsed laser beam output from a pulsed laser source, were the pulsed laser beam output has a laser beam cross sectional area with at least one cross sectional linear dimension of at least 5 mm; exposing the optical polymeric material to the pulsed laser beam output simultaneously over at least a portion of the optical polymeric material having at least one linear dimension of at least 5 mm; and controlling an intensity of the simultaneous exposure of the pulsed laser beam output over the at least a portion of the optical polymeric material to obtain an energy profile within the optical polymeric material above a nonlinear absorption threshold of the optical material and below a breakdown threshold of the optical polymeric material, and to obtain a desired change in refractive index in the at least a portion of the optical polymeric material. The intensity of the simultaneous exposure of the pulsed laser beam output may be differentially modulating over the at least a portion of the optical polymeric material to obtain a modulated energy profile within the optical polymeric material including at least some energy profile portions above a nonlinear absorption threshold of the optical material and all of the energy profile below a breakdown threshold of the optical polymeric material at which significant light scattering or absorption degrades the intended performance of the optical polymeric material, and obtaining a desired modulated change in refractive index in the simultaneously exposed portion of the optical polymeric material.

The application discloses a kind of super diffraction dark spot microscopic imaging methods based on nonlinear focal spot competition.The application carries out incoherent overlap by different wavelength of hollow light beam in focal point area, and nonlinear absorption competition of excitation photon occurs in the peripheral overlap area of fluorophore of double hollow light beam, finally generates super diffraction dark spot in focal plane, forms stable fluorescent signal in small size signal detection area, and extracts target signal by weak signal lock-in amplification technology.The application breaks through optical diffraction limit, so that it is possible to position the object to be observed in the diffraction limit region with high precision.The system requires low optical power and has high detection sensitivity, and the device structure is simple, suitable for high-resolution observation in the fields of biomedicine, nanomaterials and the like.

The invention provides a method for regulating and controlling the nonlinear absorption type of a DAST-based composite film and a preparation process of the DAST-based composite film, and relates to the technical field of nonlinear optical materials. The method comprises the following steps: compounding a guest photoelectric sensitive material DAST and a subject flexible material PMMA by adopting a blade coating technology to obtain a binary DAST / PMMA subject-guest composite film; during the process, the mass fraction of the object photoelectric sensitive material in the composite film is adjusted, so that mutual conversion between a nonlinear anti-saturated absorption behavior and a saturated absorption behavior of the composite film in a femtosecond trepanning Z scanning laser system is successfully realized. Compared with existing nonlinear absorption type regulation and control technologies such as band gap engineering of two-dimensional inorganic materials, micro-nano structure construction of organic materials, functional group modification and the like, the regulation and control method is simpler, lower in cost and more beneficial to industrial processing, and has good practical application potential in the fields of laser protection, laser mode locking, optical switches and the like.

The composition formula of the highly nonlinear transparent microcrystalline glass disclosed in the present invention is Ge 30 S 50 (CsCl) 20 , which is obtained by microcrystallization heat treatment of Ge-S chalcogenide glass material doped with CsCl, wherein the transparent microcrystal contains microcrystals with CsCl as a nucleating agent, and the microcrystals are β ‑GeS2 crystal or β ‑GeS2 crystal and α ‑GeS2 crystals coexist. The transparent microcrystalline glass of the present invention has the advantages of good chemical stability and thermal stability, high transmittance, high hardness, excellent and adjustable nonlinear absorption characteristics, easy fiber-forming and film-forming, and convenient mechanical processing. Tests show that its transmittance is between 67 and 85%, the maximum value of the nonlinear absorption coefficient is 23.48 cm / GW, and the Vickers hardness can reach up to 294 kg / mm 2 It is an excellent non-resonant nonlinear optical material for preparing optical limiting devices and has immeasurable application value in the future optoelectronic field.

The invention provides a high repetition frequency mode-locking external cavity semiconductor laser. The high repetition frequency mode-locking external cavity semiconductor laser comprises a saturable absorber region, a gain region, a phase adjustment region, a light splitting region and a micro-ring resonance region. The phase adjusting area, the light splitting area and the micro-ring resonance area form an outer cavity, the gain area provides optical gain, one side of the saturable absorption area is plated with a high-reflection film, and the saturable absorption area and the outer cavity structure jointly form an optical resonant cavity. When free spectrums of the Fabry-Perot resonant cavity and the micro-ring resonant cavity are accurately matched, the repetition frequency of the laser can be multiplied, passive mode locking is realized through the nonlinear absorption characteristic of the saturable absorber, and high repetition frequency pulse output is formed. The scheme provided by the invention has the advantages of high integration level, high stability, high repetition frequency and the like, and has important application value in the fields of data centers, optical communication, high-speed optical sampling, double-optical comb measurement and the like.

The invention relates to the technical field of photonics, in particular to a temperature fuse mechanism based on two-dimensional ferroelectric perovskite and application, and the temperature fuse mechanism comprises a fuse which is made of a ferroelectric perovskite material; the optical detection unit is used for detecting the optical signal change of the fuse and converting an optical signal into an electric signal; the signal processing unit is electrically connected with the optical detection unit and is used for comparing the electric signal with a preset critical value; and the control circuit unit is electrically connected with the signal processing unit and is used for controlling the circuit to be switched between a loop state and an open circuit state. According to the invention, by using the change of nonlinear absorption characteristics caused by the structural change of the ferroelectric perovskite material at different temperatures, the signal is cut off. Moreover, the nonlinear absorption characteristic of the ferroelectric perovskite is reversible, the ferroelectric perovskite is cut off when the preset critical temperature is reached, and then the ferroelectric perovskite can be repeatedly used, so that the cost is greatly reduced, and the utilization rate is improved.

The invention relates to the technical field of optical imaging systems, in particular to an optical imaging system capable of continuously resisting blinding caused by pulse laser damage. The system comprises a secondary imaging optical system, an imaging detector, a nonlinear absorption type optical limiter and a two-dimensional moving unit, the secondary imaging optical system comprises a primary imaging optical assembly and a secondary imaging optical assembly; after entering the secondary imaging optical system, the light beam is focused by the primary imaging optical assembly to form a primary image plane focus, and then is imaged on the imaging detector through the secondary imaging optical assembly; the nonlinear absorption type optical limiter is mounted on the two-dimensional moving unit and is arranged near a primary image plane position of a primary optical axis of the secondary imaging optical system; the two-dimensional moving unit drives the non-linear absorption type optical limiter to move, so that an incident light beam passes through different positions on the non-linear absorption type optical limiter. The device has the advantages that continuous laser protection is carried out on an imaging detector, and automatic protection of an optical imaging system is achieved.

The invention provides a large-modulation-depth dynamic saturable absorber mirror and a preparation and working method thereof, the large-modulation-depth dynamic saturable absorber mirror comprises a vanadium dioxide nano film and a gold film silicon substrate high-reflection mirror, and the film is deposited on the upper layer of a gold film of the gold film high-reflection mirror through a direct current magnetron sputtering technology to form a dynamic saturable absorber mirror device; the core mechanism is that when the dynamic saturable absorption mirror is driven by enhanced light intensity in a cavity, phase transformation and optical property dynamic transformation occur, starting from low reflectivity and high loss of a vanadium dioxide insulating phase, the state is converted into a vanadium dioxide mixed phase saturable absorption state through phase transformation equivalent nonlinear absorption, and then the state is converted into a metallic state saturable absorption state; and finally, the metal-state saturable absorption is completely saturated, so that the large-modulation-depth dynamic saturable absorption mirror is realized. According to the invention, the modulation depth of the saturable absorber mirror can be effectively improved and flexibly adjusted; and the basic temperature of the device can be regulated and controlled in a passive / active manner, so that the universality and adaptability of system application are enhanced.

The invention discloses a preparation method and application of a wafer-level palladium ditelluride-palladium diselenide vertical heterojunction thin film for a nonlinear saturable absorber. The structure of the material sequentially comprises a palladium ditelluride thin film and a palladium diselenide thin film from top to bottom, and the wafer-level two-dimensional palladium ditelluride-palladium diselenide thin film vertical heterojunction is prepared by adopting a chemical vapor deposition technology assisted by electron beam evaporation coating. Experimental results show that the nonlinear absorption performance of the obtained heterojunction thin film is superior to that of a single palladium ditelluride thin film in a visible wave band of 550 nm; in the near-infrared band of 1550 nm, the modulation depth can reach 31.92%, and the wide-spectrum response characteristic from the visible band to the near-infrared band is shown. The material obtained by the invention has the advantages of controllable wafer-level growth, excellent nonlinear performance, wide operating wavelength range and the like, provides important material strategy and theoretical support for the design of ultrafast photonic devices such as high-performance mode-locked lasers and all-optical switches, and has important application value.

The invention relates to the field of intelligent monitoring, and discloses a 300-ton large-tank stored wine far infrared ray online monitoring device, which comprises a system control unit, a remote control unit and a remote control unit, the multi-physics field coupling detection unit is used for constructing a nonlinear absorption model based on the modified Lambert-Beer law to carry out multi-physics field coupling detection; the spectral feature extraction unit is used for extracting spectral features based on a main absorption peak dynamic matching criterion; the annular mobile detection unit is used for carrying out dead-corner-free coverage scanning on the cross section of the whole tank by installing an annular guide rail system on the top of the tank; and the temperature and pressure compensation unit is used for compensating the temperature and the pressure in the tank by constructing a three-dimensional temperature field reconstruction model and correcting based on a Clausius-Claelong equation. According to the yellow rice wine acid value sensor, the principle of mid-infrared absorption spectrum is adopted, an absorption band formed by the corresponding relation between energy absorption and wavelength or wave number is recorded through infrared spectrum, and the content of organic matter in yellow rice wine is monitored.

The invention relates to a method and a system for manufacturing a polarizing body holographic grating (PVG) lens. The method comprises the following steps: a) providing a PVG lens blank; b) scanning on the PVG lens blank by using a first wavelength laser beam along a preset cutting path to form a stress concentration line; and c) scanning along the same cutting path by using a laser beam with a second wavelength, and applying thermal stress loading to the stress concentration line to guide the crack to expand from the stress concentration line so as to separate the lens blank along the cutting path. According to the invention, a two-step separation method of internal preset fracture path and external thermal shock guiding is adopted. A first wavelength laser beam (such as ultrafast laser of picosecond and the like) can form an accurate and lossless microscopic modified chain as a stress concentration line in a substrate through nonlinear absorption under the condition of not damaging the surface of a material due to the cold working characteristic of the first wavelength laser beam. The surface micro-cracks are eradicated from the source. And a second wavelength laser beam (such as infrared laser of COs and the like) generates a moving and high-gradient thermal stress field on the surface of the substrate along a preset path by utilizing the thermal effect of the second wavelength laser beam. And the stress field accurately acts on the internal fragile stress concentration line to guide cracks to controllably and smoothly expand, so that mechanical-contact-free guided fracture is realized.

The application discloses a method for calculating laser propagation distance in a water cloud system based on a plasma-optical field coupling model, comprising the following steps: calculating the number density of liquid droplets of different sizes in different water cloud systems; according to the difference in the sizes of the liquid droplets, calculating the distribution of the electron density of the plasma generated by the laser in a single liquid droplet; according to the change in the electron density distribution, calculating the feedback of the liquid droplet to the optical field and the change in the optical property of the liquid droplet; and through the calculation of the change in the optical property, calculating the nonlinear absorption of the liquid droplet to different laser intensities. Through the consideration of the scattering and absorption of the liquid droplet to the optical field, the propagation distance of the laser in different atmospheric water cloud systems can be obtained.

The application relates to a method for enhancing the nonlinear optical performance of SnS2 nanosheets through electrostatic doping. First, SnS2 nanosheets are prepared on a fluorine-doped tin oxide (FTO) substrate by a chemical vapor deposition method, and then hydrogen ion intercalated SnS2-H + The electrostatic doping causes the band gap to shrink and a strong built-in electric field to be generated, so that the nonlinear optical performance of the material is enhanced. In addition, the saturated absorption response of the material enables the application to an optical neural network as a nonlinear activation function, and exhibits application potential in machine learning tasks. The SnS2-H + The application establishes a promising and convenient nonlinear optical material, and provides new insights for the design exploration and simple synthesis of high-performance nonlinear absorption materials.

The invention relates to a method for machining a transparent workpiece (4) by generating non-linear absorption of laser radiation in a laser beam focus located in a volume of the workpiece (4). The object of the invention is that of providing a method of improved precision and quality, and a corresponding device, for laser machining of workpieces. In particular, it is also intended for it to be possible for workpieces made of composite materials or of other special materials, such as filter glass, to be machined at an improved level of quality. For this purpose, the method according to the invention comprises the following steps:spectroscopic measurement of the linear absorption of the laser radiation in the workpiece (4),selecting a working wavelength at which the linear absorption is low, andmachining the workpiece (4) by means of the application laser radiation at the working wavelength. The invention furthermore relates to a corresponding device for machining a transparent workpiece (4).

The present invention relates to a porphyrin-passivated perovskite nanofilm material and its preparation and application. The porphyrin-passivated perovskite nanofilm material comprises a perovskite material and a porphyrin molecule for passivating the perovskite material. The porphyrin molecule has an alkoxy solubilizing group, and an aniline group, a benzoic acid group, or both are connected to the meso position of the porphyrin via a π-conjugated acetylene bridge, thereby obtaining a porphyrin molecule with a passivating effect. By introducing the molecule and effectively coordinating and bonding with the perovskite defect sites, a functionalized perovskite nanofilm material is prepared. Compared with the prior art, the porphyrin-passivated perovskite nanofilm material of the present invention exhibits significantly improved excellent nonlinear absorption performance under nanosecond laser excitation in a wide wavelength range. The preparation method is simple to operate, low-cost, and applicable to perovskite materials with multiple defect problems, providing a feasible example for the development of such new photonic materials.

The invention discloses a method for regulating and controlling the nonlinearity of an optical waveguide, and belongs to the technical field of optoelectronic devices, and the method comprises the steps: constructing a waveguide structure with sub-wavelength scale periodicity, and enabling the periodicity size to meet lambda < lt >; lambda / (2n), lambda is the period length, lambda is the incident light wavelength, and n is the effective refractive index of the medium; the sub-wavelength grating waveguide is integrated on an SOI platform or a heterogeneous integrated substrate; by adjusting the unit size, the spacing, the duty ratio and the geometrical shape of the sub-wavelength structure, the effective refractive index of the waveguide is regulated and controlled, the effective mode area is increased, the electric field intensity in the unit area is reduced, and two-photon absorption TPA and free carrier absorption FCA are inhibited; and the nonlinear threshold power of the waveguide is improved by using the equivalent dielectric characteristic of the sub-wavelength structure. The non-linear absorption effect can be effectively reduced, and the power threshold value of the waveguide is remarkably improved.

This application provides a tunable optical pulse source chip, relating to the field of semiconductor optoelectronic integrated device technology. The optical pulse source chip includes: a gain region for generating and amplifying an optical signal; a pulse selection region for receiving an external periodic electrical signal to form a periodically switching switching window, through which the amplified optical signal passes or is blocked; and a saturable absorption region for nonlinearly absorbing the optical signal passing through the pulse selection region to achieve mode locking, thereby generating and outputting an optical pulse. The repetition frequency of the optical pulse is tunable by controlling the frequency of the periodic electrical signal. This application integrates the gain region, pulse selection region, and saturable absorption region monolithically, and uses a periodic electrical signal to control the switching window of the pulse selection region. The output optical pulse repetition frequency is independently controlled by the frequency of the external electrical signal, decoupling the repetition frequency from the cavity length, thus enabling a wide-range, continuously tunable pulse repetition frequency.

The invention relates to the technical field of optical neural networks, in particular to a nonlinear absorption film and a preparation and regulation method thereof. The nonlinear absorption thin film comprises a continuous film layer formed by stacking gallium indium tin liquid metal nanoparticles. Therefore, the gallium-indium-tin liquid metal in the thin film exists in the form of nano-particles, and the nano-sized gallium-indium-tin liquid metal enables the thin film to have local surface plasma resonance absorption characteristics, so that the thin film has nonlinear optical response.

The invention discloses a laser coupling system and laser processing equipment. The laser coupling system comprises a first laser source, a second laser source and a third laser source which are used for providing three beams of laser; the polarization preprocessing module is used for adjusting the polarization states of lasers emitted by the first laser source and the second laser source to be in a preset relation and combining the lasers into first combined light, and the first combined light comprises laser components of the first polarization state and the second polarization state; the electric control polarization switching module is arranged on a light path of the first combined light beam and used for receiving signals and modulating the overall polarization state of the first combined light beam; the polarization beam splitting and combining module is provided with a main input end, an auxiliary input end and an output end, the main input end receives the modulated light beam, the auxiliary input end receives the laser emitted by the third laser source, and second combined beam light is formed through selective coupling. According to the technical scheme, coupling of the main laser and the auxiliary laser can be flexibly switched, under the condition that the total energy is lower than the energy needed by the single-beam main laser to reach the threshold value, nonlinear absorption and modification of the material can be efficiently triggered, and precise machining threshold value breakthrough under lower energy input is achieved.

The invention provides a laser lossless laser printing process method, and relates to the field of laser printing methods. The method of the laser printing process without the laser damage comprises a transparent carrier plate, and comprises the following steps of: 1, preparing a groove array on the transparent carrier plate according to a grid line pattern; the core of the method of the laser-lossless laser printing process is that selective attenuation of laser energy is achieved through material modification, internal focusing is conducted on non-machining areas on the two sides of a groove through short-pulse laser (such as picosecond / femtosecond level, and the wavelength range is 343-1064 nm), local modification is initiated by a transparent material through a nonlinear absorption effect, and the laser energy is selectively attenuated through material modification. And an atomization layer of the light scattering particles is formed. The area can enable the transmission laser power to be attenuated by 50%-90%, and ensures that the residual energy is lower than the damage threshold value (generally 0.5-2J / cm < 2 >) of the photovoltaic silicon wafer. The attenuated light energy cannot reach the damage threshold value of the photovoltaic silicon wafer, and laser damage to the silicon wafer cannot be caused.