CN216818932U - Solid laser device - Google Patents

Abstract

The application discloses a laser device. The laser device comprises a shell, an electrode and a laser assembly, wherein the laser assembly is arranged in the butterfly-shaped sealing shell, the electrode penetrates through the shell, and the laser assembly is electrically connected with the electrode; wherein, the laser subassembly includes: a pumping source, a fast axis compression fiber and a laser resonant cavity; the pump source can emit pump light, the pump light is emitted to the laser resonant cavity through the fast-axis compression optical fiber, and the laser resonant cavity receives the pump light and emits pulse laser to the outside of the shell. In this way, this application establishes pumping source, fast axis compression optic fibre and laser resonator collection in the casing to through the technical scheme that the electrode that runs through the casing is the laser subassembly power supply in the casing, make laser device have compact structure's characteristics, convert the pulse laser of high peak power into through laser resonator simultaneously with the pump light, with the high peak power laser device who provides a small size, and then enlarge the civilian family expenses that laser device can carry out metal material processing and implement the scene scope.

Description

Solid laser device

Technical Field

The present application relates to the field of optoelectronic technologies, and in particular, to a solid-state laser device.

Background

In recent years, laser is widely applied to the field of laser processing because of the characteristics of good directivity, coherence, high brightness and the like, laser marking is the earliest realization and the most wide application of the field of laser processing, the current laser marking technology replaces the traditional marking and printing technology such as silk screen printing and the like, and the laser is widely applied to the field of industrial processing. At present, the laser marking machine for industrial application mainly adopts a traditional fiber laser with dozens of watts as a light source, so that the cost of the laser marking machine is higher, the volume of the equipment is larger, and the applicable scenes are quite limited. In contrast, the laser marking machine using the continuous output semiconductor blue laser as the light source has low cost and small occupied space, and is suitable for wide application. However, the semiconductor blue laser which is continuously output has a low peak power, and has a large limitation on the material of the marking material, and can be used only for laser marking of soft materials such as wood. In summary, there is a great need for a laser processing device which can process metal materials in a wider range and can be used for civil use and household use.

SUMMERY OF THE UTILITY MODEL

The technical problem that this application mainly solved provides a high peak power laser device of small volume to realize the laser device and implement the material processing of scene at civilian and family expenses.

In order to solve the technical problem, the application adopts a technical scheme that: the micro solid laser device comprises a shell, an electrode and a laser assembly, wherein the laser assembly is arranged in the shell, the electrode penetrates through the shell, and the laser assembly is electrically connected with the electrode; wherein, laser subassembly includes: the device comprises a pumping source, a fast axis compression optical fiber and a laser resonant cavity; the pump source can emit pump light, the pump light is emitted to the laser resonant cavity through the fast axis compression optical fiber, and the laser resonant cavity receives the pump light and emits pulse laser with high peak power to the outside of the shell.

Compared with the prior art, the beneficial effects of this application are: the embodiment of the application establishes the pump source, the fast axis compression optical fiber and the laser resonant cavity in the butterfly-shaped sealing shell in a centralized manner, and the technical scheme that the electrode penetrating through the shell supplies power to the laser component in the shell enables the laser device to have the characteristic of compact structure.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a laser device according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of a laser device according to another embodiment of the present application;

fig. 3 is a schematic structural diagram of a laser device in another embodiment of the present application.

Detailed Description

At present, the laser marking machine for industrial application mainly adopts a traditional active Q-switching pulse fiber laser with dozens of watts, the laser needs to adopt an active Q-switching technology and a secondary amplification technology and also needs to isolate return light, so that the pulse fiber laser has higher cost and larger equipment volume, and cannot be used for civil and household portable laser marking machines. The passive Q-switched solid pulse laser adopting a saturable absorber which is developed in recent years adopts the optical fiber coupling output of a plurality of semiconductor laser bars as a pumping source, so that the size of the laser including a laser driving power supply is large, and the laser cannot be used for a civil portable laser marking machine. After research, the inventor finds that by adopting the commonly used optical fiber output butterfly-shaped packaging structure of the semiconductor laser module and special laser related material parameter design, the butterfly-shaped packaging solid pulse laser module which can be used for civil and household metal material laser marking and has compact structure, high peak power, low cost and low power consumption can be provided.

The present application will be described in further detail with reference to the following drawings and examples. It is to be noted that the following examples are only illustrative of the present application, and do not limit the scope of the present application. Likewise, the following examples are only some examples and not all examples of the present application, and all other examples obtained by a person of ordinary skill in the art without any inventive work are within the scope of the present application.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

For a description of the laser apparatus 10 of the present application, reference is made to the following exemplary description of embodiments of the laser apparatus 10 of the present application.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a laser device according to an embodiment of the present disclosure. The laser device 10 in the embodiment of the present application may include a housing 100, an electrode 600, and a laser assembly, where the electrode 600 may include a first positive electrode 601, a first negative electrode 602, and both the first positive electrode 601 and the first negative electrode 602 are first electrodes, and the laser assembly may include a pump source 200, a beam coupler 300, and a laser resonator 400, where the beam coupler 300 may be a fast axis compression fiber, and the laser resonator 400 may include a laser input device 401, a laser gain medium 402, a saturable absorber 403, and a laser output device 404. In this embodiment, the pump source 200 may generate pump light under electrical excitation, the pump light may be incident into the laser gain medium 402 through the laser input device 401 after passing through the fast axis compression fiber to compress a divergence angle, the laser gain medium 402 generates intracavity oscillation light under the excitation of the pump light, the intracavity oscillation light may transmit oscillation in a laser resonator formed by the laser input device 401 and the laser output device 404, the saturable absorber 403 generates pulse laser with high peak power under saturable absorption effect, and the pulse laser is output through the laser output device 404; the pumping source 200, the beam coupler 300, the laser input device 401, the laser gain medium 402, the saturable absorber 403 and the laser output device 404 are all disposed in the housing 100 in a clean and sealed manner, and the sidewall of the housing 100 is disposed with a plurality of electrodes 600, wherein a first positive electrode 601 and a first negative electrode 602 penetrate through the housing 100, and the first positive electrode 601 and the first negative electrode 602 are respectively electrically connected to the pumping source 200 for providing an electrical excitation input for the pumping source 200.

In this embodiment, the housing 100 may be made of a metal material, such as oxygen-free copper or kovar alloy, and the laser assembly may be sealed in the housing 100; the pump source 200 can be welded on a bottom plate in the shell 100 through indium, the pump source 200 can be a chip semiconductor laser packaged by COS (chip operating system), and can also be a c-mount packaged chip semiconductor laser, wherein the COS packaging means that a chip is directly attached to a heat sink with a flat surface through solder, the chip is arranged on a blue film after being packaged, and a structure protected by release paper is attached, the c-mount semiconductor laser is characterized in that thin-film metal solder is plated on the heat sink, the semiconductor chip is directly welded, then a gold wire is bonded to a negative lead, the pump source 200 can be connected with a driving power supply through a first positive electrode 601 and a first negative electrode 602, and when the pump source 200 is electrically excited by continuous work or pulse modulation, the pump source 200 converts electric power into pump light; the light beam coupler 300 may be a quartz fiber with a core diameter of 50 to 400 microns, a pump light antireflection film may be prepared on the surface of the quartz fiber, the light beam coupler 300 may compress the pump light in the fast axis direction to form a divergence angle smaller than the slow axis direction, and the pump light is incident into the laser resonant cavity 400 and converted into pulse laser in the laser resonant cavity 400 to be output.

The laser cavity 400 may include a laser input 401, a laser gain medium 402, a saturable absorber 403, and a laser output 404, and the laser converter may be a laser cavity, a laser input 401, a laser gain medium 402, a saturable absorber 403, and a laser output 404The laser output devices 404 may be disposed on the same optical axis, where the laser input device 401 may be a lens, the surface of the laser input device 401 close to the laser gain medium 402 may be a plane, a convex surface, or a concave surface, a multilayer dielectric film that is anti-reflective to pump light and highly reflective to intra-cavity oscillation light may be disposed on the surface of the laser input device 401 close to the laser gain medium 402, and a pump light anti-reflective mode may be disposed on the surface of the laser input device 401 away from the laser gain medium 402; the material of the laser gain medium 402 may be Nd: YAG, Nd: YLF, Yb: YAG and the like crystals and ceramics Nd: YAG material or other material with high upper energy level life, the pumping light input surface of the laser booster 402 can be prepared with the antireflection film of pumping light and intracavity oscillation laser, or the laser input mirror can be removed, and the surface is directly prepared with the multilayer dielectric film for antireflection of pumping light and high reflection of intracavity oscillation light; the input optical surface of the laser gain medium 402 may be planar, convex, or concave; the saturable absorber 403 may be Cr^{4 +}YAG crystal or semiconductor saturable absorber or other crystal with saturable absorption function; the laser output device 404 may be a lens, the surface of the laser output device 404 near the saturable absorber 403 may be a plane, a convex surface, or a concave surface, and the laser output device 404 may be provided with a dielectric film that is partially reflective to the intracavity oscillating light, which may be provided on the surface of the laser output device 404 near the saturable absorber 403.

The pump light emitted by the pump source 200 is coupled into the laser gain medium 402 through the beam coupler 300 to generate oscillation light, the oscillation light propagates between the laser input device 401 and the laser output device 404, the saturable absorber 403 can generate pulsed laser with high peak power under saturable absorption effect, specifically, in the initial stage of pumping, when the oscillation light passes through the saturable absorber 403, the ground state electrons of the saturable absorber 403 absorb the oscillation light photons, transition to the excited state, and the photon energy is stored to the excited state of the saturable absorber 403. After the excited state absorption oscillation light photons of the saturable absorber 403 are saturated, the saturable absorber 403 is bleached, the transmittance of the saturable absorber is increased, the loss in the cavity is reduced, the Q value is increased suddenly, the photons stored in the laser resonant cavity are output through the laser output device 404 in the form of Q-switched pulses, after the Q-switched pulses are output, the ground state energy level of the saturable absorber 403 continues to absorb the oscillation light photons in the cavity, the energy accumulation of the next pulse is carried out, and the pulse laser is output through the laser output device 404.

In other embodiments of the present application, the material of the housing 100 may also be other metals such as stainless steel and aluminum alloy; the pump source 200 may be welded into the housing 100 by indium or other heat conducting material, and the welding position may be the bottom wall of the housing 100, or may be a heat sink or a bracket; the beam coupler 300 may be a fast axis compression fiber, or may be a coupling lens, when the beam coupler 300 is a fast axis compression fiber, the beam coupler 300 may be used to compress a divergence angle of the pump light in the fast axis direction, and the compression angle is not limited to this embodiment; the laser input device 401 and the laser output device 404 may be lenses, multi-layer dielectric films formed on the lenses or crystals, or other devices that can be used to transmit and reflect laser light; the laser gain medium 402 and the saturable absorber 403 may be discrete devices or may be bonded crystals.

In this embodiment, the height of the light emitting region of the pump source 200 may be 1 micron, the width may be 200 microns, the maximum output power may be 10 watts, the wavelength of the output pump light may be 808nm, and the pump source 200 operates continuously under electrical excitation; the light beam coupler 300 can be a quartz optical fiber with the diameter of 105 micrometers, a 1064nm antireflection film can be prepared on the surface of the light beam coupler 300, the light beam coupler 300 can compress the divergence angle of the pump light in the fast axis direction from 30-40 degrees to 2-3 degrees, the divergence angle of the pump light in the slow axis direction is usually 5-10 degrees, and the ratio of the long axis to the short axis of a far-field light spot of the pump light passing through the fast axis compressed optical fiber is 2.5:1-4:1, namely a near strip-shaped or near elliptical light spot; the laser input device 401 may be provided with a multi-layer dielectric film, the multi-layer dielectric film of the laser input device 401 may be directly prepared on the pump light input surface of the laser gain medium 402, and the preparation requirement of the film system may be 808nmHT (T)>95%) and 1064nmHR (R)>99.8%); the laser gain medium 402 may employ Nd: YAG laser crystal, crystal length may be 5mm, light-passing size may be 1.5mm (width) × (multiplication) 1.5mm (height), doping concentration of neodymium particles (Nd) may be 1.1%, Nd as the laser gain medium 402: another of YAG laser crystalThe 1064nm antireflection film can be prepared on each surface; the saturable absorber 403 may be bi-planar Cr⁴⁺: YAG crystal with light passing size of 1.5mm (width) 1.5mm (height), thickness of 2mm, small signal transmittance parameter of To 60%, small signal transmittance of the saturable absorber 403 of low power laser light passing through the saturable absorber, and Cr⁴⁺: 1064nm antireflection films can be prepared on two surfaces of the YAG crystal; the laser gain medium 402 and the saturable absorber 403 may be fixed to a support by a heat conductive adhesive, the support may be a copper mount, and the copper mount may be fixed to the bottom plate of the housing 100 by an indium foil; the laser output device 404 may be square, the light passing size may be 4mm (width) × 4mm (height), the thickness may be 3mm, the laser input surface of the laser output device 404 may be a plane, a partial reflection film with a reflectivity of 60% at 1064nm may be prepared, and the laser output device 404 may be fixed on the bottom plate in the housing 100 by ultraviolet glue; the housing 100 is made of an oxygen-free copper material and may have an internal dimension of 28mm (length) by 15mm (width) by 10mm (height). In this embodiment, the 808nm semiconductor laser pump source 200 operates continuously, and when the average pump current is 10A, the 1064nm pulse output laser has an average power of 2W, a pulse repetition frequency of 20kHz, a pulse energy of 100 μ J, a pulse width of 5ns, and a pulse peak of 20 kW. In other embodiments of the present application, the laser wavelength, the pumping current, the pulse repetition frequency, the pulse energy, the pulse width, and the laser power are not limited to the embodiments.

The laser device 10 can be a Q-switched operating all-solid-state laser, and the total volume of the Q-switched operating all-solid-state laser is smaller than or equal to 28mm 15mm 10mm, so that compared with lasers used in the prior art, the Q-switched operating all-solid-state laser used by the laser marking machine in the utility model has smaller size and lighter weight, the volume of the whole laser marking machine is greatly compressed, the integration of the laser marking machine in the shell 100 is possible, meanwhile, the volume of the laser device 10 is further reduced by arranging a small-volume beam coupler 300, namely a fast-axis compression optical fiber to compress laser beams, and arranging an electrode 600 penetrating through the shell 100 to provide electric excitation, and further the implementation scene range of material processing of the laser device 10 is expanded. Moreover, the laser device 10 is convenient for mass production, and reduces the requirements on tooling equipment and assembly personnel, thereby further reducing the labor cost of production and after-sale. In addition, it still has advantages such as peak power is high, the light beam quality is excellent, control is convenient, simple and easy maintenance, and sealed casing 100 can also prevent that external dust and aqueous vapor from getting into inside the laser device 10, and then prevents external environment to the harmful effects of laser device 10, and then reduces the maintenance demand of laser device 10, prolongs the life-span of laser device 10.

It should be noted that all directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiments of the present application are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

Referring to fig. 2, fig. 2 is a schematic structural diagram of a laser device according to another embodiment of the present disclosure. In this embodiment, the laser resonator 400 includes a laser input device 401, a bonding crystal 405, and a laser output device 404, wherein the bonding crystal 405 is formed by bonding the laser gain medium 402 and the saturable absorber 403. Diffusion bonding, namely, two crystals are closely attached after a series of surface treatments, optical cement is formed at room temperature, then the crystals are subjected to heat treatment, and permanent bonding is formed without other binders, and experiments show that: when the undoped crystal is bonded at two ends of the doped crystal as end caps, the temperature rise of the end face is very small and is close to the temperature of the coolant, thereby reducing the end face distortion caused by the thermal lens effect and the heat-induced wavelength shift of the light-splitting coating, and being beneficial to the stable and high-power laser operation of the laser. Therefore, the thermal bonding technology can greatly improve the thermal performance and beam quality of the laser in the aspect of laser application, and is beneficial to the integration of a laser system and the obtainment of large-size crystals. In this embodiment, the laser gain medium 402 may be Nd: YAG crystal, the saturable absorber 403 may be Cr⁴⁺YAG crystal, the laser gain medium 402 and the saturable absorber 403 may be bonded into one crystal by high temperature ion exchange, i.e., a bonded crystal 405.

In this embodiment, the total length of the bonded crystal 405 may be 6mm, the clear aperture may be 1.5mm (width) by 1.5mm (height), its Nd: YAG laser crystal part length may be 5mm, Nd ion doping concentration may be 1.1%, and Cr⁴⁺: the YAG crystal portion may have a length of 1mm and a small signal transmittance of 60%. The laser input device 401 may be provided with an antireflection film that transmits the pump light highly and a reflective film that reflects the oscillation light highly in the cavity, the laser output device 404 may be provided with a dielectric film that reflects a portion of the oscillation light in the cavity, the pump light emitted by the pump source 200 is coupled into the bonded crystal 405 through the beam coupler 300 to generate oscillation light, the oscillation light propagates between the laser input device 401 and the laser output device 404, and the bonded crystal 405 may generate a pulse laser with a high peak power under a saturable absorption effect. In other embodiments of the present application, the laser gain medium 402 bonded with the saturable absorber 403 as the bonding crystal 405 may be Nd: YAG crystal, Yb: YAG crystal.

In this embodiment, the laser device 10 further has a compact structure and a smaller volume by the bonding crystal 405 that bonds the laser gain medium 402 and the saturable absorber 403 together, thereby further expanding the range of implementation scenarios in which the laser device 10 can perform material processing.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a laser device according to another embodiment of the present disclosure. In the embodiment of the present application, the laser input device 401 and the laser output device 404 may be lenses provided with a dielectric film, or may be a dielectric film. The dielectric film in the embodiment of the present application is generally obtained by electron beam evaporation, and is prepared on the surface of the optical element and cannot be prepared separately. In this embodiment, the laser input device 401 may be a dielectric film that is highly transmissive to the pump light and highly reflective to the intracavity oscillation light, the laser output device 404 may be a dielectric film that is partially reflective to the intracavity oscillation light, the laser input device 401 may be disposed on an incident light surface of the bonding crystal 405, and the laser output device 404 may be disposed on an outgoing light surface of the bonding crystal 405, whereby the laser input device 401, the laser gain medium 402, the saturable absorber 403, and the laser are integrated into a single chipThe laser cavity 400 formed by the optical output device 404 is integrated, that is, the laser gain medium 402 may have a first surface and a second surface, the saturable absorber 403 may have a third surface and a fourth surface, the laser input device 401 may be disposed on the first surface, the laser output device 404 may be disposed on the fourth surface, and the laser gain medium 402 and the saturable absorber 403 may be bonded into a whole, specifically, the second surface of the laser gain medium 402 may be bonded into a whole with the third surface of the saturable absorber 403. In this example, the multilayer dielectric film of laser output 404 is directly prepared in Cr bonded to crystal 405⁴⁺: the laser output face of the YAG crystal portion, the reflectivity of the dielectric film may be 1064nm reflectivity R60%. In this embodiment, the 808nm semiconductor laser pump source 200 is operated under pulsed electrical excitation, wherein the pulse modulation frequency may be 1kHz, the duty cycle may be 90%, the average pump current may be 4.5A, the output laser power may be 1W, the modulation pulse width may be 900 μ s, there are 17Q-switched laser pulses, the pulse energy may be 53 μ J, the pulse width may be 2.8ns, and the pulse peak value may be 19 kW. In other embodiments of the present application, parameters such as pump wavelength, pump current, pulse width, laser power, etc. are not limited to the embodiment.

The total volume of the laser device 10 in this embodiment is less than or equal to 20mm (length) × 12mm (width) × 10mm (height), and the integrated laser resonator 400 further compresses the volume of the laser device 10, thereby expanding the range of implementation scenarios in which the laser device 10 can perform material processing. Moreover, the laser device 10 is convenient for mass production, and reduces the requirements on tooling equipment and assembly personnel, thereby further reducing the labor cost of production and after-sale. In addition, it still has advantages such as peak power is high, the light beam quality is excellent, control is convenient, simple and easy maintenance, and sealed casing 100 can prevent that external dust and aqueous vapor from getting into inside laser device 10, and then prevents external environment to laser device 10's harmful effects, and then reduces laser device 10's maintenance demand, prolongs laser device 10's life.

It should be noted that the terms "comprises" and "comprising," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Referring to fig. 1 to fig. 3, in the present embodiment, the laser device 10 further includes a second positive electrode 603, a second negative electrode 604, and a temperature sensor 700, where the second positive electrode 603 and the second negative electrode 604 are both second electrodes, the second positive electrode 603 and the second negative electrode 604 can be respectively disposed on a sidewall of the case 100 and penetrate through the case 100, and the temperature sensor 700 is disposed in the case 100 to detect a temperature inside the case 100. In the laser device 10, the laser wavelength of the pump source 200 may be affected by temperature, so that the temperature sensor 700 may be configured to detect the temperature inside the laser device 10 in real time, and the second positive electrode 603 and the second negative electrode 604 may be electrically connected to the temperature sensor 700 to output the temperature parameter of the temperature sensor 700. In this embodiment, the temperature sensor 700 may be a negative temperature feedback thermistor, the second positive electrode 603 and the second negative electrode 604 may be used to output thermistor parameters, and the temperature sensor 700 may be connected to a temperature-controlled power supply through the second positive electrode 603 and the second negative electrode 604. In other embodiments of the present application, the temperature sensor 700 may be other devices for measuring temperature. In this embodiment, the temperature sensor 700 may be disposed at the bottom of the housing 100, and may be disposed by punching a hole in the bottom, and the thermistor may be 10k Ω at 25 ℃. In other embodiments of the present application, the arrangement manner of the temperature sensor 700 is not limited to this embodiment, and when the temperature sensor 700 is a thermistor, the temperature-resistance value of the temperature sensor 700 is not limited to this embodiment.

In this embodiment, the laser apparatus 10 may further include a temperature controller, and the temperature controller may be coupled to the temperature sensor 700 to cooperate with the temperature sensor 700 to control the temperature of the TEC of the laser apparatus 10, so as to regulate the internal temperature of the laser apparatus 10 to an optimal temperature, thereby obtaining an optimized laser output power. In this embodiment, the temperature controller may be a semiconductor refrigerator, the temperature controller is connected to a power supply, the laser device 10 controls the temperature of the temperature controller according to the magnitude of the temperature control current detected by the temperature sensor, for example, after the temperature sensor detects a temperature increase, the temperature control current increases, and the temperature controller decreases the device temperature. In the embodiment of the application, the semiconductor refrigerator can cool and heat, and the cooling or heating can be realized on the same temperature controller by changing the polarity of direct current through the thermoelectric principle. It is noted that the term "coupled" is used herein to encompass any direct or indirect connection. Therefore, if a first element is coupled to a second element, the first element can be directly connected to the second element through an electrical connection or a signal connection such as wireless transmission or optical transmission, or can be indirectly connected to the second element through another element or a connection means.

In the present embodiment, the casing 100 is provided with a first positive electrode 601, a first negative electrode 602, a second positive electrode 603, and a second negative electrode 604, and the four electrodes 600 respectively penetrate through the side walls of the casing 100 to form the butterfly-shaped casing 100. The joint of the electrode 600 and the casing 100 is provided with an insulator, and the insulator is respectively sleeved on the first positive electrode 601, the first negative electrode 602, the second positive electrode 603 and the second negative electrode 604. The insulating member may be made of an insulating material to prevent short circuit caused by conduction between the electrode 600 and the housing 100, and the insulating member covering the insulating member may fill a connection portion between the electrode 600 and the housing 100 to improve the sealing performance of the laser device 10. In this embodiment, the insulating member may be a plating layer of an insulating material disposed on the surface of the electrode 600. In other embodiments of the present application, the insulating member may also be a ring set or a sealing ring made of an insulating material, and the insulating member may be disposed at the connection position of the electrode 600 and the casing 100 in an interference manner; the shape, number, and position of the electrodes 600 are not limited to the present embodiment.

The laser device 10 in this embodiment can realize the electrical connection between the inside and the outside of the housing 100 through the electrode 600 penetrating through the sidewall of the housing 100, so as to reduce the volume and the weight of the laser device 10, thereby facilitating the carrying and the use of the laser device 10 and expanding the implementation scene range of the laser device 10. It should be noted that the terms "first", "second" and "third" in the embodiments of the present application are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of the feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this embodiment, the laser device 10 may further include a heat conducting member, the heat conducting member may be fixed on the inner wall of the casing 100 in the form of a bracket, a base, or a heat conducting sheet, the laser assembly may be connected to the heat conducting member and then fixed on the inner wall of the casing 100, the heat conducting member may be made of copper, the laser assembly may be welded to the heat conducting member through heat conducting metals such as indium, and the laser assembly may also be welded to the heat conducting member through a heat conducting adhesive. In other embodiments of the present application, the shape and material of the heat conducting member are not limited to this embodiment, and the connection manner between the laser assembly and the heat conducting member is not limited to this embodiment as long as the heat conducting operation can be achieved. The laser device 10 rapidly guides out the heat generated by the laser assembly through the heat conducting member, so that the internal temperature of the shell 100 is uniformly diffused, the laser device 10 can conveniently control the internal temperature, and the temperature controller can be prevented from dissipating the heat of the laser assembly in time. The laser device 10 controls the internal temperature to the optimum temperature through the heat conducting member, the temperature controller, the temperature sensor 700 and the electrode 600, so as to regulate the internal temperature of the laser device 10 to the optimum temperature, thereby obtaining the optimum laser conversion efficiency.

In the embodiment of the present application, the temperature controller may be disposed inside the casing 100, or may be disposed outside the casing 100. In some embodiments where the temperature controller is disposed in the housing 100, the laser device 10 is further provided with a third positive electrode and a third negative electrode penetrating through the housing 100 to electrically connect the temperature controller to the power supply, in this embodiment, the temperature controller controls the temperature of the pump source 200 and the temperature difference of the housing 100, and cooperates with the temperature sensor to make the pump source 200 at the optimum temperature, that is, the temperature of the pump source 200 when the emission wavelength of the pump source 200 is the optimal wavelength, at this time, the pump source 200 and the thermistor may be bonded to the upper surface of the temperature controller by using a heat-conducting adhesive, and the lower surface of the temperature controller may be bonded to the bottom of the housing 100. In some embodiments in which the temperature controller is disposed outside the housing 100, the housing 100 does not need to be provided with a third electrode, the temperature controller needs to be connected to the housing 100, the temperature controller may include a cooling surface and a heat dissipation surface, the cooling surface is connected to the housing 100, and the heat dissipation surface is connected to a heat sink to control the temperature of the laser device 10, so as to cooperate with the temperature sensor to enable the laser device 10 to be at the optimum temperature, at this time, the outer bottom surface of the housing 100 may be bonded to the upper surface of the temperature controller through a heat conductive adhesive, and the lower surface of the temperature controller may be bonded to a heat sink with a heat dissipation function through a heat conductive adhesive; the upper and lower surfaces of the temperature controller may also be respectively heat-radiated with the lower bottom surface of the case 100 and the upper surface of the heat sink by heat-conductive silicone grease, and fixed by heat-insulating screws.

In this embodiment, the laser device 10 further includes an extractor 500, the extractor 500 is disposed at the laser output window of the casing 100, and the pulsed laser output by the laser output 404 is output to the outside of the casing 100 through the extractor 500. In this embodiment, the light extractor 500 may be a beam expander for expanding light, the beam expander may be a double-concave lens with two concave surfaces, and the beam expander may be respectively provided with an antireflection film with high transmittance for the wavelength of the output laser on the two surfaces. In other embodiments of the present application, the light extractor 500 may be other lenses, such as a lens for filtering the pump laser light, a lens for collimating the laser light, a lens for expanding a divergence angle of the laser light, a lens for compressing the divergence angle of the laser light, and the like, and is not particularly limited herein; the light extractor 500 may also be a light-permeable device other than a lens, such as an optical fiber, and is not limited in this respect.

In this embodiment, the light emitter 500 may be a biconcave beam expander for outputting laser beam, the focal length of the biconcave beam expander is-2 mm, an antireflection film with 1064nm laser wavelength output is prepared on both sides, the diameter of a laser output window of the housing 100 is 3mm, and the light emitter 500 seals the laser output window. In other embodiments of the present application, when the light extractor 500 is a biconcave beam expander, the focal length of the biconcave beam expander is not limited to this embodiment, the arrangement of the antireflection film is not limited to this embodiment, and the diameter of the laser output window of the casing 100 is not limited to this embodiment.

The laser device 10 may further include a sealing member, and the sealing member may be sleeved on the light emitter 500 to seal the housing 100, in this embodiment, the sealing member may be a sealant, and the light emitter 500 is fixed on the laser output window of the housing 100 through the sealant. In other embodiments of the present application, the sealing member may be a sealant, a sealing ring, a sealing sleeve, a welding metal, or other devices that can be used to seal the light emitter 500 in the laser output window of the housing 100, and is not limited herein.

In this embodiment, laser device 10 can be through adopting the biconcave mirror of the fixed little negative focal length of sealing glue at the laser output window department of butterfly-shaped encapsulation's casing 100, both can be used to the encapsulation, and be used for the expander beam of output laser simultaneously again, in addition, laser device 10 outside can also add the collimation focusing mirror, the pulse laser who is exported by laser output 404 passes through the biconcave expander beam and expands the back output, the beam expanding laser beam passes through the collimation focusing mirror after the focus, can obtain the tiny facula of high peak power density. The collimating focusing lens can be a convex positive lens, or other lenses or lens groups for collimating and focusing.

In the embodiment, after the laser device 10 expands the output laser through the light emitter 500, the light spot of the output laser is expanded, the convex positive lens can be placed on the output light path to collimate and focus the light beam, the larger the light spot is, the better the collimation of the collimated light beam is, and the smaller the light spot is after focusing is, so that the micro light spot with high peak power density can be obtained for laser marking, especially for laser marking of hard materials such as metal and the like.

In an embodiment of the present application, the laser apparatus 10 may increase the pulse energy and the peak power of the laser output by the laser apparatus 10 through the small saturable absorber 403 with low signal transmittance, the laser output 404 with low reflectivity for the output laser, and the laser resonator 400 with a small length (i.e., laser resonator). The principle is that the small signal transmittance of the saturable absorber 403 is reduced, so that the absorption rate of the saturable absorber 403 to the intracavity oscillation light is increased, and the pulse energy of the laser output by the laser resonant cavity 400 is increased; the reflectivity of the laser output device 404 to the output laser is low, which increases the intracavity loss of the laser resonant cavity 400, and is not easy to form intracavity oscillation light, thereby increasing the intracavity laser output threshold, further the laser resonant cavity 400 needs to absorb more energy to output laser, and further increasing the pulse energy when the laser resonant cavity 400 outputs laser; since the peak power of the output laser light is proportional to the pulse energy, the peak power of the output laser light can be controlled by controlling the small-signal transmittance of the saturable absorber 403 and the reflectance of the output laser light by the laser follower 404; in addition, the laser pulse width increases as the length of the laser cavity 400 increases, and the output laser peak power is inversely proportional to the pulse width, so that the peak power of the output laser can be controlled by controlling the length of the laser cavity 400.

The inventor finds that when the small signal transmittance of the saturable absorber 403 is not more than 60% and the reflectivity of the laser output device 404 to the output laser is not more than 60%, the peak power of the output laser is significantly improved; when the length of the laser resonant cavity 400 is not more than 15mm, the peak power of the output laser is obviously improved, and especially the marking of the metal material under the output light spot and the field lens is obviously improved. The small signal transmittance of the saturable absorber 403 can be controlled by selecting a material and adjusting a thickness.

In an embodiment of the present application, the laser device 10 may be a micro end-pumped solid-state pulse laser, the pump source 200 of the laser device 10 may be a single-chip semiconductor laser packaged by c-mount and having a laser wavelength of 808nm, a size of a light emitting region of the pump source 200 may be 1 micron high in a fast axis direction, 200 microns wide in a slow axis direction, and a maximum pump power may be 5W; the light beam coupler 300 can adopt a fast axis compression optical fiber, the diameter of the optical fiber can be 125 micrometers, an antireflection film with the wavelength of 808nm can be prepared on the surface of the optical fiber, the divergence angle of the pump source 200 in the fast axis direction can be compressed from 35 degrees to 2 degrees to 3 degrees through the fast axis compression optical fiber, the divergence angle of the pump source 200 in the slow axis direction can be 8 degrees, and the pump light emitted by the pump source 200 passes through the lightThe ratio of the long to short axes of the far field spot behind the beam coupler 300 may be 2.5:1 to 4:1, near-stripe and near-oval spot as Nd: YAG laser crystal and Cr as saturable absorber 403⁴⁺: YAG crystal can be bonded into an integral bonded crystal 405 by high-temperature ion exchange, the total length of the bonded crystal 405 can be 10mm, the clear aperture can be 3mm (wide) 3mm (high), its Nd: YAG laser crystal part length can be 8.5mm, neodymium ion doping concentration can be 1.1%, Cr⁴⁺: the YAG saturable absorption crystal part can be about 1.5mm in length, and the small signal transmittance can be 50%. The multilayer dielectric film of the laser input device 401 can be directly prepared on the pump light input surface of the laser gain medium 402, the preparation requirements of the film system can be 808nmHT and 1064nmHR, and the multilayer dielectric film of the laser output device 404 can also be directly prepared on Cr bonded with the crystal 405⁴⁺: the coating of the YAG laser output surface can be required to be 50% of the reflectivity R of 1064 nm. Because the laser device 10 adopts a bonded crystal 405 structure with a compact structure, the geometric length of the laser resonant cavity 400, namely the laser resonant cavity, can be 10mm, the 808nm semiconductor laser pumping source 200 works under continuous electric excitation, when the average pumping power is 4W, the output average laser power is 1W, the pulse repetition frequency is 20kHz, the obtained pulse energy is 50 microjoules, the pulse width is 3.5ns, the obtained pulse peak power is 14.2kW, the diameter of the laser after beam expansion and collimation can reach more than 6mm, and after the laser is focused by a field lens with the focal length of 110mm, the laser peak power density exceeds the power density threshold value of metal material marking. In another embodiment, where the laser cavity 400 has a length of 6mm, the pulse width of the laser 10 is reduced to 2.8ns and the peak laser power is increased to 17.8 kW. In other embodiments of the present application, the parameters of the laser device 10 are not limited to the embodiment.

In research experiments, the small signal transmittance of the saturable absorber 403 of the laser device 10 is 65%, the reflectivity of the laser output device 404 to the output laser is 65%, the 4W power is continuously pumped, the obtained pulse repetition frequency is 33kHz at an average output power of 1W, the calculated pulse energy is 30 microjoules, the pulse width is 3.5ns, and the pulse peak power is 8.6kW, at this time, the marking depth of the laser device 10 becomes light, the color becomes yellow, and the marking requirement of the metal material cannot be met.

In the embodiment of the present application, the peak power of the output laser is significantly increased by the saturable absorber 403 having a small signal transmittance of not more than 60% and the laser follower 404 having a reflectivity of not more than 60% for the output laser; through the laser resonant cavity 400 with the length not exceeding 15mm, the peak power of output laser is effectively improved, meanwhile, the size of the laser device 10 is obviously compressed, the small-size high-peak-power laser device 10 is further provided, and the implementation scene range of material processing of the laser device 10 is further enlarged.

To sum up, in the embodiment of the present application, the pump source 200, the beam coupler 300, and the laser resonator 400 are collectively disposed in the housing 100, and the electrode 600 penetrating through the housing 100 supplies power to the laser module in the housing 100, so that the laser device 10 has the characteristic of compact structure, and simultaneously, the pump light is converted into the pulse laser with high peak power through the laser resonator 400, so as to provide the laser device 10 with small volume and high laser output peak power, and further expand the implementation scene range of the laser device 10 capable of performing material processing, in addition, the sealed housing 100 can prevent external dust and moisture from entering the laser device 10, and further prevent the adverse effect of the external environment on the laser device 10, and further reduce the maintenance requirement of the laser device 10, and prolong the service life of the laser device 10.

The above description is only a part of the embodiments of the present application, and not intended to limit the scope of the present application, and all the equivalent structures or equivalent processes that can be directly or indirectly applied to other related technical fields by using the contents of the specification and the drawings of the present application are also included in the scope of the present application.

Claims (10)

1. A solid-state laser device, characterized by comprising: the laser device comprises a shell, a first electrode and a laser assembly, wherein the laser assembly is arranged in the shell, the first electrode penetrates through the shell, and the laser assembly is electrically connected with the first electrode;

wherein the laser assembly comprises: the laser comprises a pumping source, a beam coupler and a laser resonant cavity; the pump source can emit pump light, the pump light is emitted to the laser resonant cavity through the beam coupler, and the laser resonant cavity receives the pump light and emits pulse laser to the outside of the shell.

2. The solid-state laser device according to claim 1, wherein the beam coupler comprises a fast axis compression fiber operable to compress a dispersion angle of the pump light.

3. The solid-state laser device according to claim 1, wherein the laser resonator comprises: the laser gain medium is provided with a first surface and a second surface, the saturable absorber is provided with a third surface and a fourth surface, the laser input device is arranged on the first surface, the laser output device is arranged on the fourth surface, and the second surface and the third surface are bonded into a whole so that the laser gain medium and the saturable absorber are bonded into a whole.

4. The solid-state laser device according to claim 3, wherein the small-signal transmittance of the saturable absorber is not more than 60%, and the reflectivity of the laser output to the pulsed laser light is not more than 60%.

5. A solid state laser device as claimed in claim 3 wherein the length of the laser cavity is no more than 15 mm.

6. The solid-state laser device according to claim 1, wherein the solid-state laser device comprises an extractor, the extractor is disposed on the housing, and the laser light output by the laser module exits the housing through the extractor.

7. The solid state laser device according to claim 6, wherein the extractor comprises a beam expander mirror for expanding a spot of the laser light output by the laser assembly.

8. The solid-state laser device according to claim 6, comprising a sealing member, wherein the sealing member is sleeved on the light emitter.

9. The solid-state laser device according to claim 1, comprising a second electrode, a temperature sensor, and a temperature controller, wherein the temperature sensor is disposed in the housing, the second electrode penetrates through the housing, the temperature sensor is electrically connected to the second electrode, the temperature controller is coupled to the temperature sensor, and the temperature controller is configured to control a temperature of the solid-state laser device.

10. The solid-state laser device according to claim 9, comprising an insulator, wherein the insulator is respectively sleeved on the first electrode and the second electrode.

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