164 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 provides a multi-material laser additive forming process and a laser oscillation forming system, and belongs to the technical field of laser machining, and the multi-material laser additive forming process comprises the steps that S1, a multi-material L-PBF forming process database is formed by training a plurality of multi-material forming components; s2, a multi-material L-PBF forming process database is called, intelligent segmentation is conducted on a current component, the powder laying process and the laser oscillation forming process of all segmented parts are planned, according to the powder laying process, multi-material powder is laid layer by layer according to preset requirements, and the powder layer thickness is controlled; in the laser oscillation forming process, the multi-material molten pool is stirred through laser oscillation, and laser beams are shaped; and S3, according to the powder laying technology and the laser oscillation forming technology in the step S1, a powder laying device and a laser oscillation forming system are combined, and the multi-material component is formed. Through the powder laying technology and the laser oscillation forming technology, the powder laying device and the laser oscillation forming system are combined, and therefore the quality of formed products 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.

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

Photonic particles and methods of using particles in biological samples are disclosed. The particles are configured to emit laser light when stimulated by, for example, pump source energy. The particles may include: a gain medium having an inorganic material, an optical cavity having a high refractive index, and a coating having an organic material. The particles may be less than 3 microns along their longest axis. The particles may be attached to each other to form, for example, doublets and triplets. The particles may be injection locked by coupling an injection beam into the particles during pumping, so that the injection seeds are amplified to develop into laser oscillations. The microscope system may include a pump source, a beam scanner, a spectrometer having a resolution of less than 1 nanometer and an acquisition rate of greater than 1 kilohertz, and a spectrum analyzer configured to distinguish the spectral peaks output by the laser from a broadband background.

The invention discloses a heat-treatment-free die-casting aluminum alloy welding method based on a laser oscillation technology. The heat-treatment-free die-casting aluminum alloy welding method comprises the steps that firstly, a to-be-welded plate is pretreated; the to-be-welded plate is a heat-treatment-free die-casting aluminum alloy plate; secondly, the to-be-welded plate is clamped through a clamp, the position of a laser oscillation welding head is adjusted, and an included angle is formed between the axis of a laser beam and the vertical line direction of the to-be-welded plate; thirdly, the laser oscillation welding head emits an oscillation laser beam to weld the plate to be welded, the oscillation frequency of the oscillation laser beam ranges from 50 Hz to 200 Hz, and the oscillation amplitude ranges from 5 mm to 7 mm; and fourthly, after solution treatment, water quenching and aging treatment are conducted on the welded plate, the welded plate is cooled to the room temperature. According to the heat-treatment-free die-casting aluminum alloy welding method based on the laser oscillation technology, the problems that in the heat-treatment-free die-casting aluminum alloy welding process, welding seams collapse, the porosity is high, and the second phase is thick can be solved, and the welding quality of the heat-treatment-free die-casting aluminum alloy is improved.

The utility model provides an NPE mode-locking polarization-maintaining large-mode-field fiber laser with enhanced self-starting capability, and relates to the technical field of fiber lasers, the fiber laser comprises a pumping source and a laser oscillation cavity, the pumping source is connected with a gain fiber through a fiber beam combiner, and the laser oscillation cavity is connected with the gain fiber through a fiber beam combiner. The gain fiber is connected with a spatial light path of the laser oscillation cavity part through the photonic crystal fiber, a polarization beam splitter is arranged in the laser oscillation cavity, and a phase shifter is arranged between the polarization beam splitter and a spatial light path of the pumping source part and used for realizing nonlinear polarization rotation (NPE) mode locking; the polarization beam splitter is arranged at the position where two orthogonal polarization states transmitted in the optical fiber interfere, dual-port output of the laser is provided, vertical polarized light is output from a reflection port, horizontal polarized light is output from a transmission port, and the mode locking self-starting capacity and stability of the laser are improved.

According to the high-stability laser provided by the invention, the multi-quantum well resonance region is arranged in the laser chip, and the structure ensures that each quantum well in the multi-quantum well resonance region is strictly positioned at the wave crest of a laser standing wave field, so that the maximum gain is formed. When the wavelength is smaller than or larger than the laser wavelength, each quantum well deviates from the wavelength of the standing wave field, and the maximum gain cannot be obtained. Therefore, the structure can effectively suppress oscillation of other wavelengths and ensure that the wavelength of the output laser is stable and unchanged. Secondly, a compound semiconductor material is adopted as a gain material, and the compound semiconductor material has very short upper energy level lifetime and the gain in parabola regular distribution, so that when the laser generates oscillation, only the mode with the maximum gain forms laser oscillation, and no intense mode competition exists, thereby ensuring that the mode of the output laser beam does not generate random jump, and improving the laser output efficiency. Therefore, the intensity of the output laser is stable.

The invention discloses a narrow-linewidth thulium-doped fiber laser oscillator, which is characterized in that a saturable absorption fiber has certain absorption on signal light wavelength and is arranged between a first high-reflectivity fiber bragg grating and a second high-reflectivity fiber bragg grating, and when the laser gain exceeds the loss of a laser resonant cavity formed by the first high-reflectivity fiber bragg grating, the second high-reflectivity fiber bragg grating and a low-reflectivity fiber bragg grating, a thulium-doped fiber is generated; laser oscillation is formed and output through the low-reflection fiber bragg grating; the first and second high-reflectivity fiber gratings form an etalon effect; an etalon effect is formed between the second high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating and between the first high-reflectivity fiber bragg grating and the low-reflectivity fiber bragg grating; signal light oscillated between the first high-reflectivity fiber bragg grating and the second high-reflectivity fiber bragg grating can form standing waves, and a dynamic grating is formed in the saturable absorption fiber. Under the action of the resonant cavity vernier effect and the saturable absorption dynamic optical fiber, signal light oscillates in a narrow linewidth mode between the first high-reflectivity fiber bragg grating and the second high-reflectivity fiber bragg grating, and the narrowed signal light is injected into the thulium-doped gain optical fiber through the second high-reflectivity fiber bragg grating, so that the laser maintains narrow spectral linewidth operation.

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.

To provide a laser processing device and a laser processing method which can perform a perforating process for stably achieving a desired perforated-hole shape, at low cost and with high efficiency, on a broad thin plate, without receiving a restriction on a processing-width and without causing a perforation failure and receiving influence of vertical swinging of the thin plate, in performing the perforating process for consecutively and repeatedly forming a number of through-holes in the lengthy thin plate.SOLUTION: A laser processing device 100 is configured so that pulse light P emitted from a laser oscillating part 140 is condensed by a light condensing part 150 into a thin plate W, while transferring the thin plate W to be processed in a plate longitudinal direction of the thin plate W, which makes a galvano-scanner part 160 reflect the pulse light P so that the light points to a direction of penetrating through both sides of the thin plate W and sweeps in a plate width direction of the thin plate W while irradiating the thin plate W with the light, and makes a control part 170 perform control so that gas is jetted toward a processing area PA over the plate width direction of the thin plate W from an air nozzle body 180, in consecutively perforating a number of through-holes H.SELECTED DRAWING: Figure 1

A lancing and blood glucose level measuring device includes a casing; a laser oscillation unit that is accommodated within the casing and configured to generate a laser beam for blood sampling; a blood glucose level measuring unit that is accommodated within the casing and configured to measure a blood glucose level; a contact unit that is formed on a part of one side of the casing and configured to irradiate the laser beam toward an irradiation target area; a blood glucose strip insertion unit which is formed on another part of one side of the casing and into which a blood glucose strip including a blood glucose sensor that transmits and receives signals to and from the blood glucose level measuring unit to measure a blood glucose level is to be inserted; and a controller configured to control the laser oscillation unit.

The embodiment of the utility model provides a single-pump-source end-pumped multi-module laser, and belongs to the technical field of laser. The laser comprises a pumping source used for outputting pumping light; the spectroscope is arranged at the rear end of the pumping source and is used for carrying out light splitting operation on the pumping light so as to obtain a first light path perpendicular to a connecting line of the center of the pumping source and the center of the spectroscope and a second light path collinear with the connecting line of the center of the pumping source and the center of the spectroscope; the first total reflection mirror is arranged on the first light path and used for vertically adjusting the direction of the first light path to obtain a third light path; the first resonant cavity is arranged on the third light path, is located at the rear end of the first total reflection mirror and is used for forming laser oscillation and realizing laser output after the first gain medium absorbs the incident pump light; the first gain medium is arranged in the first resonant cavity; the second resonant cavity is arranged on the second light path and located at the rear end of the spectroscope; and the second gain medium is arranged in the second resonant cavity.

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.

A semiconductor laser element according to an aspect of the present invention comprises: an optical resonator having a first reflection portion and a second reflection portion; a gain unit disposed in the optical resonator; and a loss amount control unit provided in the optical resonator and capable of switching between a first state in which an optical loss in the optical resonator is a first loss amount, and a second state in which the optical loss is a second loss amount greater than the first loss amount. In a state in which a predetermined drive current is being supplied to the gain unit, the semiconductor laser element performs laser oscillation when the loss amount control unit is in the first state, and may not perform laser oscillation when the loss amount control unit is in the second state.

The utility model relates to the technical field of medical equipment, and provides a laser medical device. The laser medical device comprises a laser oscillation module, a mode selection module and an optical fiber coupling module. The laser oscillation module is used for generating laser; the mode selection module is in signal connection with the laser oscillation module and is used for adjusting the laser oscillation module, so that the laser oscillation module at least operates in a continuous operation mode, a quasi-continuous operation mode, a continuous Q-switching operation mode, a quasi-continuous same-frequency Q-switching operation mode or a quasi-continuous difference-frequency Q-switching operation mode; and the optical fiber coupling module is connected with an outlet of the laser oscillation module and is used for coupling the laser and the indication light. The laser medical device overcomes the defects that a thulium-doped laser in the prior art is relatively single in working mode and has limitation when dealing with various operation requirements, can achieve free switching of various modes, enables medical staff to deal with various conditions to carry out operations without replacing equipment, and improves the working efficiency of the laser medical device. And the operation efficiency is greatly improved.