96 results about "Laser oscillation" patented technology

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

The invention relates to the field of welding devices, and discloses a laser swing welding device and a welding method.The laser swing welding device comprises a supporting table, an adjusting mechanism, a swing mechanism, a laser welding head, a gradient temperature changing mechanism, a housing, an air supply mechanism, an air injection preheating mechanism and a clamping mechanism; the adjusting mechanism is arranged on the supporting table and connected with the gradient temperature changing mechanism so as to change the welding position of the laser welding head. A first plate body and a second plate body are placed on the supporting table so as to be limited by the clamping mechanism. The laser welding head is rotationally arranged on the housing and driven by the swing mechanism so as to conduct swing welding on the welding position between the first plate body and the second plate body. Through cooperation of the gradient temperature changing mechanism, the ultrasonic transducer and the gas supply and jet preheating mechanism and cooperation of the eccentric driving disc and the swing frame, preheating of protective gas, gradient cooling after welding and heating are achieved, thermal stress and thermal shock are reduced, the welding seam performance is improved, laser energy is evenly distributed, and the welding quality of dissimilar metal plates is improved.

The invention discloses a high-strength martensitic stainless steel welding method based on dual-laser collaborative oscillation scanning, which is used for welding two workpieces to be welded, at least one of the workpieces to be welded is high-strength martensitic stainless steel, and the method comprises the following steps: carrying out heat treatment on the high-strength martensitic stainless steel, the high-strength martensitic stainless steel comprises, by mass, 0.5% < = C < = 1.1%, 11.0% < = Cr < = 18.0%, 0.5% < = Mo < = 1.2%, 0.1% < = V < = 0.35%, 0.35% < = Mn < = 0.5%, 0.35% < = Si < = 0.45% and the balance Fe. Performing oscillation scanning welding on the two to-be-welded workpieces which are butted, mounted and fixed through first oscillation laser; and laser oscillation scanning in-situ heat treatment is carried out on a hardened area in the weld joint heat affected area through second oscillation laser. By means of the method, the defect problem that high-strength martensitic stainless steel is extremely prone to having welding cracks, hardened areas and the like due to high strength can be avoided, meanwhile, the welding process is simplified, the welding efficiency is improved, and the mechanical property is guaranteed.

In an LD-pumped solid-state laser, where a solid-state laser crystal is excited by excitation light emitted from an LD to cause laser oscillation, and the resulting laser oscillation light of two frequencies is converted into a sum frequency, stable operation and cost reduction are achieved. [Solution] In an LD-pumped solid laser 1 comprising a solid laser crystal 19, an LD 11 that emits excitation light to excite the solid laser crystal 19, a resonator that resonates the light emitted from the solid laser crystal 19, and an optical wavelength conversion element 22 that converts the wavelength of solid laser oscillation light L21 and L22, a multiplexing means 21 is provided that receives the two solid laser oscillation light L21 and L22 from different directions and combines them into one, and the optical wavelength conversion element 22 converts the combined solid laser oscillation light L21 and L22 into a sum frequency.

A pulse generation unit generates a driving voltage signal including a pulse signal. A laser oscillation module oscillates a laser beam by carrying out, based on the driving voltage signal, a pulse oscillating operation. When the power command signal has a voltage command value corresponding to a laser power greater than a predetermined laser power during a high period, the pulse generation unit modulates, in a pulsed manner, a voltage value of the high period of the driving voltage signal so as to alternately repeat, for a preset period of time from a rising time of the high period of the driving voltage signal, a high state in which the voltage value is maintained and a low state in which the voltage value is lowered by a predetermined voltage value without being lowered to a voltage value of a low period of the driving voltage signal.

Provided is a glass material which has a low linear thermal expansion coefficient and which can be used more stably as a laser medium. The glass is characterized by containing, in terms of mol%, 45%-85% of SiO2, 3%-23% of Al2O3, 0%-13% of B2O3, 0%-5% of Li2O, and 0.01%-11% of Ln2O3 (Ln is at least one selected from Ce, Nd, Yb, Er, Pr, Sm, Eu, Tb, Dy, Ho, and Tm). The glass is preferably used as a wavelength conversion member 26 of a laser oscillation device 2 that extracts laser light by emitting excitation light L from an excitation light source 20. The wavelength conversion member 26 is disposed between a resonator 22 and a resonator 24.

A laser beam irradiating unit of a laser processing apparatus includes a laser oscillating mechanism. The laser oscillating mechanism includes a group setting unit configured to, on a condition that a pulsed laser beam is applied at shorter time intervals than a length of time that molten debris is generated, set the number of pulsed laser beams to be applied until a time that the molten debris is solidified and set the number of pulsed laser beams as one group. A time interval setting unit is configured to set a time until heat generated by application of the pulsed laser beams of the one group is cooled, which serves as a time interval between the one group and an adjacent group, and set time intervals of the pulsed laser beams constituting the one group. The laser oscillating mechanism sets a repetition frequency with the one group as one unit.

A laser processing method and apparatus for printed circuit boards are provided, which effectively utilize a laser oscillator to optimize processing efficiency and quality. The laser processing method uses a laser oscillator to perform laser processing by applying RF pulses to oscillate the laser. During laser output after the application of the RF pulse ends, the RF pulse is applied again to continue laser oscillation, and a desired duration of laser light is extracted from the continuously oscillating laser for laser processing of the printed circuit board.

The present invention discloses a method, system, device, and medium for controlling narrow-gap pre-fill welding. The method first obtains a top-view image of the pre-filled weld groove region with orthogonal horizontal and vertical scale lines. The method then uses the top plane of the pre-set slats as the pre-welding plane, measures the groove width of the pre-welding plane, determines the groove center coordinates based on the top-view image, and calculates the laser oscillation amplitude based on the groove width. The method then adjusts the light spot centering position based on the groove center coordinates and the laser oscillation amplitude based on the calculated laser oscillation amplitude. Finally, when the light spot centering position satisfies a first preset condition and the laser oscillation amplitude satisfies a second preset condition, a welding enable signal is triggered to proceed with welding. The present invention can solve the problem of poor sidewall fusion in narrow-gap pre-fill welding and improve welding efficiency and quality.

The application discloses a multi-mode vortex laser with adjustable order, comprising: a cavity lens coated with a laser wavelength anti-reflection film system, a first laser output mirror and a second laser output mirror, both of which are plane mirrors, and both of which are coated with a film system partially transmitting laser wavelength on one side and an anti-reflection film system for laser wavelength on the other side; a high-order Laguerre-Gaussian beam is focused by the cavity lens, and the focused beam waist positions of each-order Laguerre-Gaussian mode vortex light are separated under the action of spherical aberration of the cavity lens, and the higher the mode order and the larger the spot size, the closer the focused beam waist of the mode to the cavity lens; the positions of the first laser output mirror and the second laser output mirror are adjusted so as to be located at the waist positions of a certain mode, and the first laser output mirror and the second laser output mirror located at different positions provide feedback for two different-order Laguerre-Gaussian mode vortex lights, so that multi-mode vortex laser oscillation and output are formed.

The invention discloses a laser and arc composite oscillating welding device, comprising a welding gun, a laser head, a connecting assembly, a filament spacing adjustment assembly, a motor drive assembly and an angle adjustment assembly; the connecting assembly comprises a flange connecting column, a main body rib plate, an oscillating welding gun main body connecting plate and a laser head connecting plate, the oscillating welding gun main body connecting plate is connected to the filament spacing adjustment assembly and the motor drive assembly, and the laser head connecting plate is fixed to the laser head; the angle adjustment assembly is connected to the motor drive assembly, and the welding gun is fixed to the angle adjustment assembly; the invention combines laser oscillation and arc oscillation to obtain a laser and arc composite heat source, giving full play to the advantages of laser and arc composite welding and oscillating welding; at the same time, by increasing the melt width, the acceptable weld gap of the welding process is increased and the fault tolerance of the workpiece assembly is improved; by stirring the molten pool, the flow behavior of the molten pool is changed to make the distribution of metal elements in the weld more uniform; by combining the heat sources, the heat input is increased and the penetration depth is increased.

The invention relates to the technical field of solid laser, and discloses a quasi-three-level laser with end-side composite pumping, which comprises a quasi-three-level laser crystal, an end-side pumping assembly, a side pumping module and a laser resonant cavity. The end face pumping assembly is used for injecting end face pumping light to the end face of the crystal. The side pumping module is used for injecting side pumping light to the side face of the crystal, and the laser resonant cavity and the quasi-three-level laser crystal are matched to form a laser oscillation circuit. Through the arrangement, the end face pumping assembly is used for providing high-power-density pumping light, the problem of high excitation threshold of the quasi-three-level laser crystal is solved, and population inversion and laser gain are effectively established; and meanwhile, large-area and high-pumping power input is carried out by virtue of the side pumping module, so that uniform allocation of a pumping heat load, reduction of a temperature gradient and end surface stress in the crystal and inhibition of a thermal lens effect are effectively realized, consideration of high-power density excitation of the crystal, low thermal stress and uniform thermal distribution is realized, and high-efficiency and high-power laser output of the laser is ensured.

An extreme ultraviolet light generation apparatus includes a first light source outputting first excitation light, a laser oscillator including an active medium and performing laser oscillation by irradiating the active medium with the first excitation light to output the laser light, a measurement instrument measuring a pulse energy and a pulse time width of the laser light, a temperature regulator that adjusts a temperature of a cooling medium that cools the first light source, and a processor. The processor controls the temperature regulator to adjust the temperature of the cooling medium so that the pulse energy measured by the measurement instrument falls within a target range of the pulse energy, and adjust a current value of a current supplied to the first light source so that the pulse time width measured by the measurement instrument falls within a target range of the pulse time width.

The present invention discloses a fiber laser amplifier based on hierarchical heat dissipation, which relates to the field of high-brightness fiber lasers. The fiber laser amplifier comprises: a fiber laser seed source, a pigtail semiconductor pump source, a first-stage fiber oscillator component, and a second-stage fiber laser amplifier component. The semiconductor pump light and the laser seed light are combined and injected into the first-stage fiber oscillator component, and the low-brightness semiconductor pump light is converted into a higher-brightness transition laser through a laser oscillation process with a lower quantum loss. The second-stage fiber laser amplifier component converts the transition laser into the laser seed light and outputs a high-brightness main laser. Based on the configuration of the pigtail semiconductor pump source, the present invention effectively distributes the heat generated by the quantum loss to two-stage components for heat dissipation, while also reducing the heat concentration on the single-stage component and improving the reliability of the amplifier.

The invention provides a laser welding method for a medium-thick-wall solid rocket engine shell. The laser welding method comprises the following steps that S1, a welding face is pretreated; s2, fixing to form a shell assembly; step S3, hoisting; s4, determining a circular seam program by utilizing an industrial robot demonstrator; and S5, a front end socket welding seam between the front end socket and the combustion chamber shell is welded, and the welding process comprises the following steps that S5.1, laser spot welding is conducted; s5.2, laser oscillation penetration fusion welding is carried out; s5.3, MIG welding is carried out; and S6, a rear end socket welding seam between the rear end socket and the combustion chamber shell is welded. According to the method, the welding process is divided into three processes, the operation difficulty is greatly reduced, the fault tolerance range of the process interval range is larger, and the reliability of batch production is higher; and through a step-by-step welding method, digging and discharging are easy, the production precision is greatly improved, and the risk of reworking is reduced.

A system for transmitting laser power to a remote receiver, comprising a laser diode, an optical system for collimating and focusing the laser beam to the receiver, and a scanning system for directing the beam towards the receiver. The beam has a wavelength of 1150 to 1550 nm, a power exceeding 300 mW, an emitter width of 15 to 250 μm, is a spatial multimode beam, and more than 50% of its power is transmitted via TEM. 00 In the mode, less than 15% of its power, and a higher-order TEM with more than 20 (n+m) nm The mode has a laser oscillation cavity with a Fresnel number between 0.01 and 20, and a low-speed axis M of less than 15. 2 , high-speed axis M less than 1.5 2 It has a high-speed axial divergence angle exceeding 60°. The collimated laser beam has a single lobe when imaged up to a range of 10 meters.

The application provides a 2.8 mu m single-frequency fiber laser based on a pump-enhanced saturable absorber and belongs to the technical field of mid-infrared laser. The linear resonant cavity of the laser is composed of a low-refractivity fiber grating and a high-refractivity fiber grating, and a first pump coupler, an erbium-doped fluoride gain fiber, a pump light stripper and a pump-enhanced saturable absorber filter device are sequentially arranged in the cavity. The filter device contains enhanced pump light injected by a second pump source through a second pump coupler and used for exciting the absorption characteristics of the erbium-doped saturable absorption fiber; the laser of the first pump source is used for pumping the gain fiber to generate laser oscillation, and the enhanced pump light is used for forming a MHz-level ultra-narrow band dynamic grating in the saturable absorption fiber. The dynamic grating and the static filter of the fiber grating work cooperatively to realize stable single-longitudinal-mode selection, and finally the single-frequency laser is output from the first fiber end cap. The application realizes compact structure and high stability of 2.8 mu m single-frequency laser output.

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.

The application discloses a semiconductor laser with an exciton polaron topological layer, which comprises, from bottom to top, a substrate, a lower confining layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper confining layer in sequence, and has the exciton polaron topological layer; the exciton polaron topological layer comprises a first exciton polaron topological layer, a second exciton polaron topological layer and a third exciton polaron topological layer, the first exciton polaron topological layer is located between the lower confining layer and the substrate, the second exciton polaron topological layer is located in the lower confining layer, and the third exciton polaron topological layer is located between the lower confining layer and the lower waveguide layer. The application uses exciton polaron as a medium for population inversion, enhances the stability of exciton polaron quasi-particles, enhances the laser oscillation of the laser, reduces the threshold current of the energy level particle number inversion of the laser, and improves the capture effect of the depletion region, the deep energy level trap and the insulating interface layer.

The application relates to the field of semiconductor lasers, and discloses an elliptical deep groove narrow ridge semiconductor laser which comprises, from bottom to top, a substrate, an N limiting layer, an N waveguide layer, a quantum hydrazine active layer and a P waveguide layer, the surface of the quantum hydrazine active layer is provided with two shoulder portions, a ridge waveguide is arranged between the two shoulder portions, a groove is formed between the shoulder portions and the ridge waveguide, and elliptical deep grooves are arranged on the two sides of the ridge waveguide, the long arc edges of the elliptical deep grooves intrude into the ridge waveguide to form a narrow ridge waveguide, the elliptical deep groove narrow ridge semiconductor laser suppresses high-order mode participation in laser oscillation through the elliptical deep groove narrow ridge waveguide structure, mode filtering and wave far-field spot optimization of the laser are realized, the purity of the fundamental mode output is effectively improved, and the spot quality is optimized.

The application relates to the field of welding devices, and discloses a laser swing welding device and a welding method. The laser swing welding device comprises a supporting table, an adjusting mechanism, a swing mechanism, a laser welding head, a gradient temperature changing mechanism, a cover, a gas supply mechanism, a jet preheating mechanism and a clamping mechanism. The adjusting mechanism is arranged on the supporting table and connected with the gradient temperature changing mechanism to change the welding position of the laser welding head. The supporting table is provided with a plate body I and a plate body II to be limited by the clamping mechanism. The laser welding head is rotationally arranged on the cover and driven by the swing mechanism to swing weld the welding position between the plate body I and the plate body II. The gradient temperature changing mechanism, the ultrasonic transducer, the gas supply and the jet preheating mechanism are cooperated, the eccentric driving disc and the swing frame are cooperated, the protective gas is preheated, the post-welding gradient cooling and heating are realized, the thermal stress and the thermal shock are reduced, the welding performance is improved, the laser energy is uniformly distributed, and the welding quality of the dissimilar metal plates is improved.

To provide a laser device having a higher modulation speed, a high device yield, and improved array compatibility under either cooled or uncooled operating conditions.SOLUTION: An active layer structure 20 between a semiconductor substrate 30 and a grating structure 40 configured for operation, comprising a common active layer, a first facet 50-1 and a second facet 50-2, wherein the grating structure comprises spatially adjacent integrated grating sections, a cladding structure 70 for optical confinement of laser light, a DFB structure 60-1 with a first grating section 42-1, and a DBR structure 60-2 with a second grating section 42-2, the first grating section and the second grating section share a common active layer for the integrated grating section, the DFB structure includes a first optical function as a lasing function, and the DBR structure includes a second DBR structure as an optical feedback.SELECTED DRAWING: Figure 1

The invention relates to the technical field of laser, and provides a wide-tuning narrow-linewidth mid-infrared light parameter laser generation device, which comprises a pump laser oscillation cavity and an optical parameter laser oscillation cavity, and is characterized in that the pump laser oscillation cavity is used for generating pump laser; the pumping laser oscillation cavity comprises a pumping laser gain module, a pulse modulation module, a line width narrowing module, an optical isolation module, a first reflecting mirror and at least two second reflecting mirrors; the optical parametric laser oscillation cavity comprises an optical parametric oscillation nonlinear crystal module, a line width narrowing module, a first reflecting mirror and at least two third reflecting mirrors, the pumping laser oscillation cavity and the optical parameter laser oscillation cavity are both annular cavities and are nested with each other. The annular pump laser oscillation cavity and the optical parameter laser oscillation cavity are nested with each other, and high-stability simultaneous narrowing control of the pump laser line width and the wide tuning optical parameter signal laser line width is realized by using the same line width narrowing module, so that the requirement of wide tuning narrow line width intermediate infrared idler frequency light stable output is met.

A semiconductor laser element includes a laser section configured to cause light to perform laser oscillation, an amplification section configured to amplify the light, an active region extending to the laser section and the amplification section, a first anti-reflection coating provided on an end face of the laser section opposite to the amplification section with respect to the laser section, and a second anti-reflection coating provided on an end face of the amplification section opposite to the laser section with respect to the amplification section. In a plan view, an area of the active region in the amplification section is larger than an area of the active region in the laser section.

This laser oscillation device is provided with: a pair of mirrors; a laser medium; an attenuator that causes the laser light to be in a non-resonant state at a first attenuation rate and causes the laser light to be in a resonant state at a second attenuation rate; and a control unit. The control unit causes the attenuator to maintain the attenuation rate of the second attenuation rate so that the laser light oscillates as a continuous wave during a first period, and causes the attenuator to switch the attenuation rates of the first attenuation rate and the second attenuation rate so that the laser light oscillates as a pulse wave during a second period that is continuous with the first period. The first period is longer than the time from the time at which the first time is switched to the second attenuation rate to the time at which the second time is switched to the second attenuation rate in the second period.

The invention discloses a modulation pulse laser processing method and system based on scanning graphs and frequency adjustment, and belongs to the field of laser processing. The modulation pulse laser processing method comprises the following steps: setting laser power, scanning frequency, scanning amplitude and duration time of each section in different sections of an energy field to enable the laser power, the scanning frequency and the scanning amplitude of continuous laser to periodically and alternately change to generate modulation pulse laser; generating a preset laser oscillation track according to a preset laser scanning pattern, the processing speed and the modulation frequency and the modulation duty ratio of the modulation pulse laser; and enabling the modulation pulse laser to act on the to-be-processed workpiece according to a preset laser oscillation track to form a molten pool, and carrying out laser processing. On the basis of existing laser beam oscillation scanning, a scanning laser pulse effect is formed. The method has the characteristics of eliminating pores by scanning laser, refining crystal grains and being low in pulse laser heat effect at the same time, and the mechanical property is improved.

This invention provides a method for welding ultra-high strength steel cylinders, comprising the following steps: Step S1, grinding away the oxide film on the surface of the area to be welded; Step S2, mounting the cylinder to be welded onto an internal support mechanism; Step S3, a robot moves the laser welding head to align it with the weld seam; Step S4, laser spot welding is performed first; Step S5, figure-eight laser oscillation welding is performed. This invention uses an internal support mechanism to tighten the cylinder to be welded, and the extension degree of the support block is adjustable, adapting to cylinders of various sizes; through the cooperation of the welding fixture and the laser head, figure-eight oscillation laser welding is used, resulting in better forming effect and lower porosity; the longer arc-ending time allows for complete melting on the back side of the weld while maintaining a higher weld height on the front side; the structure is simple, the operation is convenient, and it is applicable to various types of cylinders, effectively reducing welding costs while ensuring welding efficiency and quality.

[Problem] To prevent light reflected by a light-emitting unit from returning to a light source and affecting the laser oscillation frequency of the light source. [Solution] This light-receiving device comprises: a measurement optical system that generates measurement light having a frequency that shifts at least discretely to two or more levels; and a light processing unit that causes prescribed oscillation light and return light of the measurement light from an object being measured to interfere with each other. The measurement optical system has a light-emitting unit that transmits the measurement light. The measurement optical system is also capable of transmitting the measurement light through laser resonance caused by at least inner-surface reflection of the light-emitting unit.

The present invention provides a multi-material laser additive forming process and a laser oscillation forming system, belonging to the field of laser processing technology, including step S1: forming a multi-material L-PBF forming process database by training multiple multi-material forming components; S2: calling the multi-material L-PBF forming process database, intelligently segmenting the current component, and planning the powder laying process and laser oscillation forming process for each segmented part, wherein the powder laying process lays multi-material powder layer by layer according to preset requirements and controls the thickness of the powder layer; the laser oscillation forming process stirs the multi-material molten pool and shapes the laser beam through laser oscillation; S3: forming a multi-material component according to the powder laying process and laser oscillation forming process in step S1, and combining a powder laying device and a laser oscillation forming system. The present invention improves the quality of the formed product by using the powder laying process and laser oscillation forming process, and combining a powder laying device and a laser oscillation forming system.

This laser device is provided with: a light extraction unit that extracts, from incident light, light in a wavelength band that contributes to laser oscillation; and a laser resonance unit that is provided with a medium into which the light of the wavelength band extracted by the light extraction unit is incident.