111 results about "Tophat beam" patented technology

The invention discloses a method for generating a flat-topped beam array, and the method comprises the steps: introducing a multi-Gaussian function and a hyperbolic function, carrying out the superposition of the hyperbolic function, and constructing a weighting function and a kernel function with Gaussian distribution intensity based on the superposed hyperbolic function and multi-Gaussian function; introducing a partially coherent light construction formula, and constructing a cross spectral density function of a multi-cosine multi-Gaussian correlation light field containing a multi-cosine function at a source plane by combining a weighting function and a kernel function; introducing a free space transmission formula, and constructing a light intensity expression of the multi-cosine multi-Gaussian correlation light field at any transmission distance according to a cross spectral density function of the multi-cosine multi-Gaussian correlation light field, namely, an expression of the multi-cosine multi-Gaussian correlation light field; adjusting parameters of the transmission distance and the multi-cosine multi-Gaussian correlation light field to obtain flat-topped beam arrays with different row numbers and column numbers, and realizing an array form with adjustable flat-topped sub-beams; according to the invention, the number of the sub-beams of the flat-topped beam array can be effectively regulated and controlled.

The invention discloses a method for processing the marking depth problem of laser marking equipment. The method comprises the steps of optimizing an optical system design, constructing an automatic equipment calibration process, strengthening the environmental adaptability of the equipment, optimizing a control algorithm to be matched with an industrial application scene, processing the problem of inconsistent marking depth, monitoring and adjusting the direction and path of a laser beam in real time and the like. A flat-topped beam converter, an aspherical lens, a temperature-controllable optical platform and other optimized optical systems are combined with a high-precision camera, a sensor, an algorithm and the like to realize real-time monitoring and dynamic adjustment of a reflector angle, a laser track, environmental parameters, a marking path, power and the like, so that the laser marking depth is consistent, the direction is accurate, the path is not inclined, and the laser marking quality is improved. The machining precision and stability of the laser marking equipment are improved, and the laser marking equipment is suitable for different materials and process requirements.

The invention discloses a method for regulating and controlling a cosine multi-Gaussian correlation structure light field, and the method comprises the steps: introducing a hyperbolic cosine function and a multi-Gaussian function, and constructing a weighting function and a kernel function based on the hyperbolic cosine function and the multi-Gaussian function; introducing a partially coherent light construction formula, and constructing a cross spectral density function of a cosine multi-Gaussian correlation structure light field at the source plane by combining a weighting function and a kernel function; introducing a free space transmission formula, and constructing a light intensity expression of a cosine multi-Gaussian correlation structure light field at any transmission distance according to a cross spectral density function, namely, an expression of the cosine multi-Gaussian correlation structure light field; adjusting the transmission distance and parameters of the cosine multi-Gaussian correlation structure light field to obtain light intensity distribution regulation and control of the cosine multi-Gaussian correlation structure light field, and further obtaining an array form in which sub-beams are flat-topped beams according to the light intensity distribution regulation and control; according to the invention, controllable transmission of the cosine multi-Gaussian correlation structure light field can be realized, and effective regulation and control of the array form in which the sub-beams are flat-topped beams can be realized.

The invention is suitable for the technical field of laser processing, and provides laser processing equipment. The laser processing equipment comprises a laser device used for emitting a laser beam; the light path switching system is used for deflecting the laser beam to a flat-topped light path or a Gaussian light path, the laser beam is output in a flat-topped light beam mode through the flat-topped light path, and the laser beam is output in a Gaussian light beam mode through the Gaussian light path; the processing head is used for deflecting the emergent direction of the flat-topped light beam output by the flat-topped light path or the Gaussian light beam output by the Gaussian light path and guiding the flat-topped light beam or the Gaussian light beam to a preset processing position; and the controller is coupled to the light path switching system through communication and is used for controlling the light path switching system to switch the laser beam between the flat-topped light path and the Gaussian light path according to processing requirements. In the embodiment of the invention, the laser processing equipment can be quickly switched among the laser beams in different modes, so that the processing efficiency can be improved.

The embodiment of the invention discloses an etching method, an etching device and a perovskite assembly. The etching method is used for etching a top electrode of a battery to be etched. The etching method comprises the following steps: shaping a Gaussian beam into a square flat-topped beam; adjusting a preset focusing position of the square flat-topped light beam; controlling the to-be-etched battery and the square flat-topped light beam to reach relative positions, and controlling the to-be-etched battery and the square flat-topped light beam to move relatively along a first direction and / or a second direction; and etching the to-be-etched cell according to the preset focusing position, so that the depth of an etching groove formed by etching is greater than or equal to the thickness of the top electrode and less than the sum of the thickness of the top electrode and the thickness of the perovskite functional layer. According to the technical scheme provided by the embodiment of the invention, the Gaussian beam is converted into the square flat-topped beam, and the focal depth lower edge of the generated square flat-topped beam only acts on the top electrode on the surface of the film layer, so that the actual use power is reduced, the influence of laser on other functional layers in the perovskite component can be avoided, and the performance of the perovskite component is improved.

The invention relates to the technical field of optical fiber device manufacturing, and discloses a femtosecond laser inscribing low-polarization-dependent-loss optical fiber grating method and system, and the method comprises the steps: firstly, synthesizing an initial phase comprising a flat-topped beam phase, an astigmatism correction phase and a defocus phase, and loading the initial phase to a spatial light phase modulator; therefore, a preset circular flat-top focusing light spot is generated. Secondly, collecting a three-dimensional light field image sequence of a focusing light spot in a low-power detection mode, reconstructing light intensity distribution, extracting effective focal depth and ovality characteristic parameters, dynamically optimizing a phase through a closed-loop feedback mechanism until light field characteristics reach a preset target, and obtaining an optimized phase; and finally, loading an optimized phase in a high-power inscribing mode, and controlling the axial scanning of the optical fiber to inscribe the grating. Accurate active regulation and control of the three-dimensional shape of the focused light field and closed-loop self-optimization of process parameters are realized, birefringence caused by anisotropy of a refractive index modulation area is inhibited from a physical mechanism, and polarization dependent loss of the fiber bragg grating is fundamentally reduced.

The invention discloses a composite additive system based on programmable laser beam-double arcs and a working method of the composite additive system. The composite additive system is mainly composed of a laser unit, a beam shaping unit, a deformation optical unit, a double-arc unit, a double-wire-feeding unit, a substrate unit and a light spot shape unit. According to the system, Gaussian laser is converted into a flat-topped beam through a pi Shaper collimation beam shaper, and the shape and intensity distribution of a light spot are dynamically regulated and controlled by combining an electromagnetic actuating self-adaptive optical element; the double arc units cooperate around the laser beam to achieve gradient deposition of heterogeneous materials such as titanium / aluminum and the like in cooperation with an independently-controlled wire feeding system. A closed-loop feedback mechanism is adopted, molten pool parameters are monitored in real time through an optical sensor, laser power, electric arc parameters and wire feeding speed are dynamically adjusted, and molten pool stability and metallurgical reaction control precision are remarkably improved. The system can meet the multi-material composite additive manufacturing requirements of multifunctional parts of complex structures, and is particularly suitable for efficient forming of high-performance titanium-aluminum alloy components in the aerospace field.

The invention relates to the technical field of laser beam shaping, discloses an active test method and system for a circuit breaker, and is used for solving the problem that the self-adaptive shaping capability of a CO2 laser beam is difficult to improve by the existing method. Firstly, a stable light path is constructed, and the stability of the light path is ensured through mechanical limiting, a thermal management module and multi-stage optical alignment; then low-power calibration is carried out, a deformable mirror initial driving table is generated through a least square inversion algorithm, and a flat-topped beam reference is established; data are collected through a wavefront sensor, a high-order mode is reconstructed, the voltage of a deformable mirror is dynamically refreshed, and wavefront control and scanning motion synchronization is ensured in combination with scanning galvanometer time sequence synchronization, closed-loop control and exception handling; monitoring the temperature of the deformable mirror, starting water-cooling adjustment, and correcting the driving table to cope with the heat effect; finally, a safety system is constructed, laser power, wavefront distortion and deformable mirror stroke parameters are monitored, dry gas purging is conducted on the diffractive optical element regularly, and safety guarantee and performance verification of the whole process are achieved.

The invention provides an unmanned aerial vehicle wireless energy supply method and system based on multiband laser and intelligent tracking and pointing, and relates to the technical field of unmanned aerial vehicle wireless energy transmission. The method comprises the following steps: dynamically selecting a 1064nm or 1550nm laser band according to a real-time distance between the unmanned aerial vehicle and a transmitting end, and shaping a Gaussian beam into a flat-topped beam through a variable-focus collimating lens group; a tracking and aiming mode combining coarse tracking and fine tracking is adopted, in fine tracking, through an infrared beacon and a CCD image servo closed loop, observation noise covariance is dynamically estimated in combination with a Transform-AKF fusion algorithm, and process noise covariance is adjusted in a self-adaptive mode; the offset of the reflection light spots is detected through the reverse reflector to realize jitter compensation; fusing the fine tracking angle and the jitter compensation amount to generate a final aiming instruction; meanwhile, according to energy feedback data and tracking errors of a receiving end, laser output power is adjusted in a self-adaptive mode through a PID algorithm. According to the invention, long-distance, high-precision and self-adaptive unmanned aerial vehicle wireless energy transmission is realized.

The invention discloses a laser cladding method for a wind power sliding bearing, and particularly relates to the technical field of laser cladding. The method comprises the following steps that a wind power gear box pin shaft is fixed to a positioner and adjusted to be axially horizontal, and a laser cladding head is positioned to the position above the central axis of the pin shaft through an industrial robot; laser cladding is conducted in a synchronous powder feeding mode, a cladding head is controlled to horizontally move in the axial direction, meanwhile, a positioner drives a pin shaft to rotate, and a spiral coating is formed on the surface of the pin shaft in a cladding mode; and after single-layer full covering is completed every time, the cladding head is moved reversely to conduct next-layer cladding, coating thickness accumulation is achieved through direction alternation and interlayer superposition, and the technology is terminated till the preset value is reached. By the adoption of the technical scheme, the problem that in the prior art, a sliding bearing is insufficient in friction and wear performance is solved, a flat-topped beam is adopted to replace a traditional Gaussian beam for cladding, the particle size of powder is refined, and the prepared coating has the advantages of being few in crack defect and good in friction and wear performance.

The invention discloses an automatic focusing optical system and visual detection equipment with the same, and relates to the technical field of optical detection. The system comprises a focusing module, the focusing module comprises a light source, a collimation unit and a beam expanding unit, the collimation unit is used for collimating a Gaussian beam emitted by the light source into a flat-topped beam, the beam expanding unit comprises a micro-lens array and a convex lens which are sequentially distributed in the emergent direction of the flat-topped beam, and a shielding piece is arranged on the light incident side of the convex lens; the front surface of the micro-lens array is used for dividing the flat-topped light beam into a plurality of sub-light beams, the rear surface of the micro-lens array is used for mutually superposing the focused sub-light beams to form a homogenized light beam, and the convex lens is used for expanding the homogenized light beam into parallel light beams; and the detection module comprises an objective table and an imaging unit, the objective table is used for bearing the to-be-detected sample, and the imaging unit is used for imaging and focusing through the parallel light beams reflected by the to-be-detected sample. By adopting the system provided by the invention, the uniformity of linear light spots can be obviously improved, and burrs and noise are eliminated.

The invention relates to a dynamic light beam shaping system and method based on a spatial light modulator. The system comprises a laser light source module, a beam expanding collimation light path, a light beam modulator, a focusing optical assembly, a detection and feedback module and a control and optimization module. According to the method, the uniformity of the output flat-topped beam can be corrected by virtue of a random parallel gradient descent (SPGD) algorithm and combining a Zernike polynomial as a control variable. Meanwhile, a composite performance index comprehensively considering energy distribution and shape features is constructed, the correction process of the flat-topped beam is accelerated by adopting a mode of gradually improving Zernike polynomial orders in multiple stages, the convergence trend of the performance index is used as a judgment basis of stage switching, stage independent variable dimension expansion is implemented, and the correction precision of the flat-topped beam is improved. And the convergence speed is obviously improved. Besides, adaptive selection of disturbance amplitude and learning rate parameters in the SPGD algorithm is realized by using noise estimation and a local linearity index, and the robustness of the system to noise and environmental disturbance is enhanced.

The invention discloses a flat-topped beam uniformity optimization and centroid position control feedback system and method, and belongs to the technical field of automatic feedback control. The problems that an optical element needs to be frequently adjusted in a traditional method, and the same accuracy and reaction speed are difficult to achieve in a method of manually adjusting the optical element in an optical path are solved. The closed-loop feedback system comprises a laser, a first lens, a second lens, a first reflector, a second reflector, a third reflector, a spatial light modulator, a polarization beam splitter (PBS), an achromatic lens, a fourth reflector, a camera, a computer, a high-voltage amplifier, piezoelectric ceramics and a lambda / 2 wave plate. The position and intensity distribution of the flat-topped light beam are dynamically adjusted through a real-time image processing technology, and an experimenter does not need to manually adjust optical elements in a light path. The method is more flexible and higher in precision. The innovation not only helps to improve the accuracy and efficiency of the experiment, but also provides important support for smooth development and development of the experiment.

The utility model provides a particle counter which comprises a shell, a light channel used for light beam propagation and a cavity used for scattering are arranged in the shell, the light channel is communicated with the cavity, and a light source assembly used for emitting light beams, a light guiding assembly, a scattered light collecting assembly and a light collecting structure are sequentially arranged from the light channel to the cavity. A light beam enters the cavity after being guided by the light guiding assembly, the scattered light collecting assembly and the light collecting structure are combined with the shell at the position of the cavity, the light source assembly and the light guiding assembly are sequentially arranged on a light channel path along a light beam propagation path, and the light guiding assembly comprises an optical fiber and a lens set. The lens group comprises a first cylindrical lens, a second cylindrical lens and a second focusing lens. According to the utility model, the particle counter can obtain more homogenized flat-topped light beams, so that the light intensity of light spots in a photosensitive area is more uniform, and stray light in the process that the light beams are emitted from a laser to be removed by a light trap can be reduced at the same time.

The invention discloses a double-flat-topped light beam diamond polishing device and method based on homogenized optical fibers, and relates to the technical field of semiconductor material laser processing. The light spot homogenizing unit homogenizes the pulse laser to obtain a square flat-topped light spot; the light spot shaping unit collimates the homogenized pulse laser into parallel light and adjusts the beam diameter; the beam splitting and sub-transfer unit splits the parallel light into two sub-light beams, the two sub-light beams are adjusted to be coplanar and parallel to each other, and the center-to-center distance between the two sub-light beams is adjustable; the laser processing head unit focuses the two sub-light beams on the surface of the diamond; and the three-dimensional motion platform is used for bearing the diamond and scanning and polishing the diamond. Multi-focus array parallel scanning increases the coverage area of single-time processing, the processing effect of traditional single-focus multi-time scanning can be achieved through one-time scanning, the scanning frequency is remarkably reduced, the processing time consumption is reduced, and the processing efficiency is improved.

The invention relates to a parallel multi-beam pulse laser welding device and a working method. A workbench is used for bearing a to-be-machined material, and a moving mechanism drives a fusion welding mechanism to achieve lifting motion and front-back and left-right movement on the horizontal plane. The fusion welding mechanism executes laser welding and is provided with at least one set of laser heads, and laser beams generated by the laser transmitter are sent into the laser heads through the modulator. In the modulator, after a laser beam generated by a laser transmitter sequentially passes through a beam expanding device, an energy control system, a reflecting mirror and a first semi-transparent and semi-reflecting mirror, one path of light enters a pulse delay device driven by a one-dimensional motion platform to adjust pulse delay, and the other path of light is reflected and converged and then is shaped into a flat-topped light beam through an aspheric surface shaping system; and after the light passes through the second semi-transparent and semi-reflecting mirror, one part of the light enters the image acquisition module driven by the one-dimensional motion platform to control focusing imaging, and the other part of the light enters the laser head after being diffracted by the concave lens.

The invention relates to a high spatial resolution array SERF atom magnetometer based on light beam homogenization, which provides a new idea for the realization of a miniaturized multi-channel atom magnetometer and lays a foundation for the development of high spatial resolution magnetic field detection, a portable multi-channel atom magnetometer and a biological magnetic imaging technology. Comprising an alkali metal gas chamber located in a magnetic compensation coil, a 3 * 3 photodiode array is arranged on the laser emergent side of the alkali metal gas chamber, the laser incident side of the alkali metal gas chamber is connected with a flat-topped beam shaper through a 1 / 4 wave plate, and the flat-topped beam shaper shapes light spots with incident light intensity in Gaussian distribution into flat-topped light spots with light intensity evenly distributed. The flat-top light spots sequentially pass through the 1 / 4 wave plate and the alkali metal gas chamber along the z axis and then cover the photodiode array located on the xy plane, and nine photodiodes in the photodiode array form nine signal channels for receiving the flat-top light spots from nine positions.

The present invention provides a filamentation cutting head, a laser cutting system and a design method for a filamentation cutting head, which relate to the field of laser control technology. The filamentation cutting head includes a shaping element, a collimating element and a focusing element arranged in sequence along the propagation direction of light. The laser beam emitted by the laser is converted into a flat-top beam by a shaping element having a first surface shape, and its divergence angle is controlled by the collimation of the collimating element. Finally, it is converged into a target filamentation beam with high energy utilization and high uniformity by a focusing element having a second surface shape. This filamentation beam can realize laser cutting of hard and brittle materials and improve the processing effect. At the same time, the filamentation cutting head adopts a full-refractive element, which not only has the advantages of a simple design method, low lens processing difficulty, and the ability to cope with a variety of materials, but can also convert all Gaussian beams into flat-top beams, so that all input energy is utilized in the filamentation beam.

The invention relates to the technical field of lasers, in particular to a multi-wavelength coaxial line polarization homogenization laser system which comprises a laser light source, a collimation module, a coaxial beam combination module and a homogenization module. The laser light source is used for outputting a plurality of linearly polarized lasers; the collimation module is used for matching the laser spot to collimated laser with a target size; the coaxial beam combining module is used for integrating the multi-wavelength laser to the same light path and enabling the coaxiality to be smaller than or equal to 0.01 mrad; the homogenizing module comprises an aspheric lens, an aspheric mirror, a concave-convex lens and a biconvex lens, the aspheric lens is used for expanding the light beams, and the aspheric mirror, the concave-convex lens and the biconvex lens are used for converting the Gaussian light beams into uniform flat-topped light beams, so that the homogenizing module eliminates multi-wavelength dispersion and outputs coaxial laser beams with the light intensity uniformity larger than or equal to 90%. According to the multi-wavelength coaxial line polarization homogenization laser system, the multi-wavelength coaxiality and the light intensity uniformity can be improved, and meanwhile, the complexity of the laser system is reduced.

The invention discloses a laser illumination and imaging lens group for a shadow imaging system, the laser illumination and imaging lens group comprises an illumination lens and an imaging lens, the illumination lens shapes a Gaussian beam into a flat-topped beam, and the flat-topped beam uniformly irradiates an object to be observed; the imaging lens images the target area to obtain a shadow contour image of the observed object. The illumination lens comprises a first lens with negative focal power and a second lens with positive focal power, and the first lens and the second lens are both aspheric lenses. The imaging lens comprises a front lens group, an aperture diaphragm and a rear lens group, the front lens group comprises a third lens, a fourth lens, a seventh lens and an eighth lens with positive focal power, and a fifth lens and a sixth lens with negative focal power, and the rear lens group comprises a ninth lens with negative focal power and a tenth lens with positive focal power. And all the lenses are spherical lenses. While the collimation and dodging effects of the laser beams are ensured, the system also has the advantages of long working distance, high resolution and the like, can meet the observation requirements of a non-luminous high-speed small-size moving object, and expands the application field of a shadow imaging system.

The present application belongs to the field of optical devices and proposes a collimated flat-top Gaussian beam converter, comprising: a beam expansion lens group, a polygonal gradient refractive index lens array, an aspheric focusing lens, a polygonal gradient refractive index fiber image transmission bundle, and a collimating element; the beam expansion lens group is used to expand and collimate the incident light, and the expanded and collimated light is incident on the polygonal gradient refractive index lens array. The light output from the polygonal gradient refractive index lens array is focused onto the image-side focal plane of the aspheric focusing lens after passing through the aspheric focusing lens; one end face of the polygonal gradient refractive index fiber image transmission bundle is placed at the image-side focal plane of the aspheric focusing lens, and the other end is placed at the object-side focal plane of the collimating lens. The collimated flat-top beam converter of the present application is capable of converting a non-uniform Gaussian beam emitted by a light source into a flat-top beam, thereby improving the uniformity of light energy distribution in the exposure area and overcoming the defect that the working spot of a traditional Gaussian beam is bright in the center and dark at the edges.

The invention discloses equipment and a method for measuring the length of a high-speed rotating blade. The method comprises the following steps: acquiring a collimated Gaussian beam through a light source collimation module; converting the collimated Gaussian beam into a flat-topped beam with uniformly distributed intensity through a collimation and homogenization converter; a blade tip detection light path of the to-be-detected workpiece is obtained through a light beam reflection module according to the symmetrically arranged light beam reflection ends; the blade tip detection light path comprises a light path of incident light obtained by carrying out light path direction conversion on the flat-topped light beam; performing straight edge diffraction on the blade tip edge of the to-be-detected workpiece through the incident light to obtain a light path of diffracted light containing blade tip size information of the to-be-detected workpiece; a light beam receiving and demodulating end is used for receiving and demodulating diffraction fringe intensity distribution of diffraction light containing blade tip size information so as to reconstruct blade length parameters of a to-be-detected workpiece. According to the invention, the problems of poor light beam collimation, poor light spot uniformity and poor blade tip measurement precision existing in the actual use of the existing measuring instrument are solved.

The invention discloses shaping laser annealing equipment and method for a silicon-based heterojunction cell, and the equipment comprises a laser, a light path and a quick connection assembly, the output end of the laser is fixedly connected with the light path, and the light path is fixedly connected with a beam expander. The diffraction optical element can be taken out during later maintenance, and maintenance is simple and convenient; during machining, the light path is adjusted, laser emitted by the laser can pass through the center of the diffraction optical element reflector, the diffraction optical element in the light path enables machining plane light spots to be distributed in a flat-topped light beam energy mode, the flat-topped light beam energy is concentrated, energy loss is reduced, ablation damage caused by too high local energy is avoided, and machining precision is improved. The resistivity is generally reduced after processing, optimal processing parameters exist, the resistivity is reduced by about 25% on the basis that the substrate and the transparent conductive film layer are not damaged by the shaping laser annealing process, and the processing efficiency and the annealing quality of the heterojunction cell are effectively improved.

The invention discloses a Gaussian beam shaping rod mirror optimization method. The method comprises the following steps: S1, calculating the spatial distribution of laser beams through ray tracing; s2, according to the physical model of the flat-topped light beam, deriving a mapping function relational expression of any light on an incident plane and an emergent plane, and constructing an optimization algorithm evaluation function; s3, performing optimization design on the optical structure of the rod mirror shaping system through a particle swarm optimization algorithm; and S4, evaluating the machinability of the rod mirror shaping system by using tolerance analysis. The processing feasibility of the optical element can be determined, the stability of the shaping system is improved, the design difficulty of the beam shaping system is reduced, and a better beam shaping effect and a higher energy utilization rate are realized.

The invention relates to the technical field of element detection, and discloses a laser-induced breakdown spectroscopy measurement system based on light field regulation, which comprises a laser light source, a control device, a beam expanding device and a focusing acquisition device, and the control device is connected with the laser light source. Through the combined effect of the first diaphragm and the second diaphragm, the initial state of a laser beam is optimized, the first diaphragm mainly reduces irregularity and scattering components in the beam, the second diaphragm blocks an uncollimated beam, so that a stable and uniform initial beam is formed, and after the beam is processed by the DOE diffraction element, the laser beam is not collimated by the second diaphragm. And the light beam is further converted into a flat-topped light beam, so that the light beam energy is uniformly distributed on the surface of the sample, thereby avoiding the formation of an irregular pit shape with an over-deep center and an over-shallow edge in the ablation process of the traditional Gaussian light beam, improving the uniformity of the shape of the ablation pit, reducing the fluctuation of spectral data, and improving the measurement accuracy. And a foundation for improving the element distribution detection precision is also laid.

The invention relates to the field of atomic interference measurement, in particular to an atomic Raman interferometer based on a flat-topped beam. Comprising two Raman interference subsystems arranged in parallel, each of the two Raman interference subsystems comprises an ultrahigh vacuum cavity and a light path system, and the light path system comprises a flat-topped beam shaping module located on one side of the high vacuum cavity and a Raman light Doppler sensitive configuration module located on the other side of the high vacuum cavity; in the flat-topped beam shaping module, the holographic algorithm principle is adopted, the actual size of atoms in an interference area is combined to determine the size of a target flat-topped beam, the initial complex amplitude is precisely constrained, and a final diffraction phase is obtained through iterative optimization. After the Raman light passes through the diffraction phase, the Raman light is shaped into a flat-topped light beam with a target size and uniform intensity distribution at the ultrahigh vacuum cavity, so that the coherence efficiency under the same interference time is remarkably improved.

The invention relates to a laser beam shaping system. The laser beam shaping system comprises a laser light source used for generating an initial light beam; the aspherical lens group is arranged on a propagation path of the laser beam and comprises a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged from the object space to the image space along the incident direction of the light source; wherein the first lens and the second lens are plano-concave aspheric lenses and both have negative focal lengths; the third lens is a biconcave aspheric lens and has a negative focal length; the fourth lens is a biconvex aspheric lens and has a positive focal length; the initial light beam is collimated by the lens group to form a target flat-topped light beam, and meanwhile, the aperture of the light beam realizes beam expansion of a preset multiplying power.

The invention provides an optical device and a laser. The optical device comprises a first light splitting module, N light beam shaping modules and N second light splitting modules, n is a natural number greater than or equal to 2; the first light splitting module receives an input light beam and splits the input light beam into N Gaussian light beams in a time domain; the light beam shaping modules are arranged on the light emitting side of the first light splitting module, correspond to the Gaussian light beams one to one and convert the Gaussian light beams output by the first light splitting module into flat-topped light beams; the second light splitting modules are arranged on the light emitting side of the light beam shaping module, correspond to the flat-topped light beams in a one-to-one mode and divide the flat-topped light beams into at least two beams of output light in the spatial domain. According to the optical device and the laser, the high-energy requirement and the high-repetition-rate requirement of precision machining are met, and the productivity is greatly improved; the light beams segmented in time can be independently controlled, and the flexibility is greatly improved.

The application discloses a method for generating a flat-top beam array, comprising the following steps: introducing a multi-Gaussian function and a hyperbolic function, superimposing the hyperbolic function, constructing a weight function and a kernel function with Gaussian distribution intensity based on the superimposed hyperbolic function and the multi-Gaussian function; introducing a partial coherent light construction formula, combining the weight function and the kernel function to obtain a cross-spectral density function of a multi-cosine multi-Gaussian correlation light field containing a multi-cosine function at a source plane; introducing a free space transmission formula, constructing an intensity expression of the multi-cosine multi-Gaussian correlation light field at an arbitrary transmission distance according to the cross-spectral density function of the multi-cosine multi-Gaussian correlation light field, that is, an expression of the multi-cosine multi-Gaussian correlation light field; adjusting the transmission distance and the parameters of the multi-cosine multi-Gaussian correlation light field to obtain a flat-top beam array with different numbers of rows and columns, and realizing an array form with adjustable flat-top sub-beams; and the application can effectively control the number of the flat-top beam array sub-beams.

The invention discloses a femtosecond laser operation flat-topped beam shaping optical system which comprises a laser, a beam expander, a DOE shaping module and a focusing scanning module. The laser is used for outputting a femtosecond Gaussian laser beam, and the femtosecond Gaussian laser beam sequentially passes through the beam expander, the DOE shaping module and the focusing scanning module and then acts on an operation area; the beam expander is used for expanding the diameter of the femtosecond Gaussian laser beam to the beam diameter used for cutting the light path; the DOE shaping module comprises a DOE diffractive optical element; the DOE diffractive optical element is arranged on a path of the femtosecond Gaussian laser beam and is used for converting an incident Gaussian beam into a flat-topped beam with uniformly distributed energy through phase modulation; the flat-topped light beam has no local energy peak value, thermal damage and excessive ionization of traditional Gaussian laser to normal tissues of eyes are avoided, postoperative inflammatory response is light, the tissue recovery speed is increased, and the risk of operative complications is reduced.