CN102248286A - Linear polarization pulse fiber laser processing device - Google Patents
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- CN102248286A CN102248286A CN2011101643796A CN201110164379A CN102248286A CN 102248286 A CN102248286 A CN 102248286A CN 2011101643796 A CN2011101643796 A CN 2011101643796A CN 201110164379 A CN201110164379 A CN 201110164379A CN 102248286 A CN102248286 A CN 102248286A
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Abstract
The invention provides a linear polarization pulse fiber laser processing device. The linear polarization pulse fiber laser processing device comprises a linear polarization solid laser, a plurality of amplification stage units, a polarization related collimation isolator, a polarization optical splitter and a lambda/4 wave plate, wherein the linear polarization solid laser is used for generating linear polarization pulse laser; the plurality of amplification stage units comprise a polarization related isolator, a pumping source, a polarization related combiner and double-cladding polarization maintaining optical fiber respectively; the polarization related collimation isolator, the polarization optical splitter and the lambda/4 wave plate are arranged on one side of the final output end of the plurality of amplification stage units sequentially, so that laser output and amplified by the plurality of amplification stage units passes through the polarization related collimation isolator, the polarization optical splitter and the lambda/4 wave plate and then is irradiated on a processed workpiece; and after laser, which is reflected by the processed workpiece and returns along the optical axis, passes through the lambda/4 wave plate, the polarization direction of the laser is changed to be vertical to the original polarization direction, so that the laser is reflected vertical to the optical axis by the polarization optical splitter. According to the linear polarization pulse fiber laser processing device, the linear polarization pulse fiber laser has high stability, low cost and a function of preventing reflected light.
Description
Technical field
The present invention relates to a kind of linear polarization pulsed optical fibre laser processing unit (plant) that is used for industrial processes, belong to laser technology field.
Background technology
Along with development of technologies, laser processing technology has been widely used in industrial circles such as mark, cutting, welding, punching, coating as the representative of modern industry high-tech process technology.Develop in the optical fiber laser of the nineties in last century, with traditional CO
2Laser instrument is compared with solid state laser, have that volume is little, energy consumption is low, beam quality high good, efficient is high, stability is high, characteristics such as non-maintaining, is progressively replacing the status of conventional laser in industrial processes.Wherein, the pulse optical fiber with high repetition frequency, high-peak power, high single pulse energy receives much concern at aspects such as Laser Micro-Machining, laser labelling, laser cutting, laser weld.
Yet unsettled seed source amplifies the high energy pulse that can produce non-flashlight through gain fibre, not only bad for processed and applied, also can serious threat comprise seed source, pumping source even safety whole laser-processing system on the contrary.Secondly, in process, the part of the light that is reflected by surface of the work can enter laser instrument, may damage device, even burn optical fiber.Moreover, being subjected to the higher restriction of Primary Component cost at present, the cost of the industrial pulse optical fiber on the market is also very high, has also limited the popularization of its application.So, need have and can prevent reverberation and the low pulse optical fiber of cost cost in high stability, high light beam quality, the processing.
Summary of the invention
The present invention puts in view of the above problems and makes, and its purpose is to provide the linear polarization pulsed optical fibre laser processing unit (plant) that is used for industrial processes that a kind of stability is high, cost is low and have antireflection light function.
In order to achieve the above object, the invention provides a kind of linear polarization pulsed optical fibre laser processing unit (plant), comprising: the linear polarization solid state laser is used to produce the linear polarization pulse laser; A plurality of amplifying stages unit comprises polarization be correlated with relevant bundling device of isolator, pumping source, polarization and double clad polarization maintaining optical fibre respectively, and the linear polarization pulse laser by described linear polarization solid state laser output is amplified; And the relevant collimation of polarization isolator, polarizing beam splitter and λ/4 wave plates that are configured in final output one side of described a plurality of amplifying stages unit successively, make and after the relevant collimation of the described polarization of laser process isolator, polarizing beam splitter and λ/4 wave plates through amplifying of the output of described a plurality of amplifying stages unit, be radiated on the work piece, and, the laser that is returned along optical axis by described processed object reflection is through after described λ/4 wave plates, its polarization direction becomes vertical with former polarization direction, thereby is reflected to the direction vertical with optical axis by described polarizing beam splitter.
In addition, preferably, described linear polarization solid state laser comprises linear polarization solid laser module, beam-expanding collimation mirror, condenser lens and the coupling output optical fibre of configuration successively.
In addition, preferably, going into of the relevant isolator of polarization of the first order amplifying unit in the coupling output optical fibre of described linear polarization solid state laser and the described a plurality of amplifying stages unit is fine by drawing the welding of awl method to realize mould field coupling.
Moreover, preferably, adopt the fiber end face welding of mould field coupling between described a plurality of amplifying stages unit.
In addition, preferably, the pumping input of the relevant bundling device of polarization of a relevant bundling device of the polarization of the previous amplifying stage unit in described a plurality of amplifying stages unit and a back amplifying stage unit is added to fine quantity or improves the single armed pump power according to needed pumping general power.
According to aforesaid the present invention, can realize that stability is high, cost is low and have the linear polarization pulsed optical fibre laser processing unit (plant) that is used for industrial processes of anti-reflective function.
Description of drawings
Fig. 1 is the integrally-built figure of linear polarization pulsed optical fibre laser processing unit (plant) that is used for industrial processes that expression the present invention relates to.
Fig. 2 is the figure of the internal structure of the linear polarization solid state laser 1 in the above-mentioned linear polarization pulsed optical fibre laser processing unit (plant) of expression.
Description of reference numerals:
1, linear polarization solid state laser, 2, the relevant isolator of pre-amplifying stage polarization,
3, pre-amplifying stage pumping source, 4, the relevant bundling device of pre-amplifying stage polarization,
5, pre-amplifying stage double clad polarization maintaining optical fibre, 6, the relevant isolator of main amplifying stage polarization,
7, main amplifying stage pumping source, 8, the relevant bundling device of main amplifying stage polarization,
9, main amplifying stage double clad polarization maintaining optical fibre, 10, the relevant collimation of polarization isolator,
11, polarizing beam splitter, 12, λ/4 wave plates,
13, absorber of light, 14, work piece,
15, linear polarization solid laser module, 16, the beam-expanding collimation mirror,
17, condenser lens, 18, the coupling output optical fibre.
The specific embodiment
Below, describe the specific embodiment of the present invention in detail in conjunction with Fig. 1, Fig. 2.
Fig. 1 is the integrally-built figure of the linear polarization pulsed optical fibre laser processing unit (plant) that is used for industrial processes that the present invention relates to of expression, and Fig. 2 is the figure of the internal structure of the linear polarization solid state laser 1 in the above-mentioned linear polarization pulsed optical fibre laser processing unit (plant) of expression.
As shown in Figure 1, the linear polarization pulsed optical fibre laser processing unit (plant) that relates to of present embodiment comprises: linear polarization solid state laser 1; The pre-amplifying stage unit that constitutes by the relevant isolator 2 of pre-amplifying stage polarization, pre-amplifying stage pumping source 3, the relevant bundling device 4 of pre-amplifying stage polarization and pre-amplifying stage double clad polarization maintaining optical fibre 5 etc.; The main amplifying stage unit that constitutes by the relevant isolator 6 of main amplifying stage polarization, main amplifying stage pumping source 7, the relevant bundling device 8 of main amplifying stage polarization, main amplifying stage double clad polarization maintaining optical fibre 9 etc.; And the relevant collimation of polarization isolator 10, polarizing beam splitter 11, λ/4 wave plates 12 and the absorber of light 13 etc. that are connected to workpiece one side of above-mentioned main amplifying stage unit in turn.
The linearly polarized laser that is produced by linear polarization solid state laser 1 enters into pre-amplifying stage unit.
In this pre-amplifying stage unit, above-mentioned linearly polarized laser enters pre-amplifying stage pumping source 3 and carries out pumping through after the relevant isolator 2 of pre-amplifying stage polarization.The relevant isolator 2 of this pre-amplifying stage polarization is to allow light to the passive device of a direction by stoping to pass through round about, its effect is that the direct of travel to light limits, make light can only folk prescription to transmission, can be isolated well by isolator by the light that the optical fiber echo reflection is returned, thereby improve the efficiency of transmission of light wave, prevent in the light path because a variety of causes produces the back harmful effect that light source and light path system is produced to transmission light.
Afterwards, the pump light from pre-amplifying stage pumping source 3 outgoing enters the relevant bundling device 4 of pre-amplifying stage polarization.The relevant bundling device 4 of this pre-amplifying stage polarization is a kind of end pumping devices, and it has high coupling efficiency, is convenient to constitute seamless link with other optical fibre device, is used for pump light is coupled into pre-amplifying stage double clad polarization maintaining optical fibre 5.Then, through pump light propagation in pre-amplifying stage double clad polarization maintaining optical fibre 5 of the relevant bundling device 4 of pre-amplifying stage polarization, the while is absorbed and generation one-level amplification pulse laser by the working-laser material in the pre-amplifying stage double clad polarization maintaining optical fibre 5.
Then, the laser that is produced by above-mentioned pre-amplifying stage unit enters main amplifying stage unit.
The formation of the formation of main amplifying stage unit and above-mentioned pre-amplifying stage unit is basic identical, also is to be made of the relevant isolator of polarization, pumping source, the relevant bundling device of polarization, double clad polarization maintaining optical fibre etc.In main amplifying stage unit, laser carries out pumping through the relevant isolator 6 laggard amplifying stage pumping sources 7 of becoming owner of of main amplifying stage polarization.Wherein, the relevant isolator 6 of main amplifying stage polarization is to allow light to the passive device of a direction by stoping to pass through round about, its effect is that direction of light is limited, make light can only folk prescription to transmission, thereby the light of returning by the optical fiber echo reflection can be isolated well by isolator, improve the efficiency of transmission of light wave, prevent thus in the light path because a variety of causes produces the back harmful effect that light source and light path system is produced to transmission light.
Afterwards, enter the relevant bundling device 8 of main amplifying stage polarization from the pump light of main amplifying stage pumping source 7 outgoing, the relevant bundling device 8 of this main amplifying stage polarization is a kind of end pumping devices, it has high coupling efficiency, be convenient to constitute seamless link, be used for pump light is coupled into main amplifying stage double clad polarization maintaining optical fibre 9 with other optical fibre device.Then, propagate in main amplifying stage double clad polarization maintaining optical fibre 9 through the pump light of the relevant bundling device 8 of this main amplifying stage polarization, this pump light is produced secondary amplification pulse laser by the absorption of the working-laser material in the main amplifying stage double clad polarization maintaining optical fibre 9 simultaneously.
Then, after the laser that is produced enters the relevant collimation of polarization isolator 10, remain the linear polarization pulse laser from what the output of the relevant collimation of polarization isolator 10 obtained.It is back to transmission bad light source of light loss and light path system that the relevant collimation of this polarization isolator 10 is used to prevent to amplify the issuable high energy pulse in back etc. through gain fibre.
Afterwards,, become after the circularly polarized light by polarizing beam splitter 11 and λ/4 wave plates 12 successively, be radiated on the surface of work piece 14 and carry out Laser Processing via the linear polarization pulse laser of the relevant collimation of polarization isolator 10.In process, reflection back, the surface of a part of light work piece 14 is returned along former road, enters λ/4 wave plates 12 successively and becomes linearly polarized light.At this, its polarization direction becomes the direction vertical with former polarization direction, therefore, when it enters polarizing beam splitter 11, is polarized optical splitter 11 and is separated to direction towards absorber of light 13, and absorbed by absorber of light 13, thereby reach the effect of antireflection light.
In above-mentioned pre-amplifying stage unit and main amplifying stage unit, the signal input part phase welding of relevant with each polarization respectively bundling device 4,8 of output of the relevant isolator 2,6 of each polarization, and fine phase welding is gone in the pumping of the relevant bundling device 4,8 with each polarization of the tail optical fiber of each pumping source 3,7.In addition, the end welding mutually of the output of the relevant bundling device 4,8 of each polarization and each double clad polarization maintaining optical fibre 5,9.And, the other end of pre-amplifying stage double clad polarization maintaining optical fibre 6 and the fine phase welding of going into of the relevant isolator 6 of main amplifying stage polarization; The relevant fine phase welding of going into that collimates isolator 10 with polarization of the other end of main amplifying stage double clad polarization maintaining optical fibre 9 thus, can obtain the linear polarization pulse laser at the relevant output that collimates isolator 10 of polarization.
In addition, the optical fiber at all weld two ends all is preferably the core diameter matched fiber more than.
Moreover, exemplified in the present embodiment laser has been carried out the linear polarization pulsed optical fibre laser processing unit (plant) that secondary amplifies, but the present invention does not limit the progression that laser amplifies, can select multistage structure for amplifying according to required laser power, wherein, each level all can be made of the relevant isolator of polarization, the relevant bundling device of polarization, pumping source and double clad polarization maintaining optical fibre.
Further, illustrate the internal structure of the linear polarization solid state laser 1 in the above-mentioned linear polarization pulsed optical fibre laser processing unit (plant) with reference to Fig. 2.
As shown in Figure 2, the linear polarization solid state laser 1 of the seed source unit of pulse optical fiber comprises linear polarization solid laser module 15, beam-expanding collimation mirror 16, the condenser lens 17 of configuration successively and the output optical fibre 18 that is coupled as a whole.At this base,, behind beam-expanding collimation mirror 16 and condenser lens 17, enter into coupling output optical fibre 18 from the linear polarization pulse laser of linear polarization solid laser module 15 outputs.In addition, above-mentioned coupling output optical fibre 18 and the pre-relevant isolator 2 of amplifying stage polarization goes into fibre and can be welded together by drawing awl method etc.Linear polarization solid state laser 1 is not limited to said structure, as long as laser instrument that can output line polarized pulses light.
In addition, above-mentioned pre-amplifying stage pumping source 3 and main amplifying stage pumping source 7 can be the optical fiber coupling way of outputs.In addition, the pumping input of relevant bundling device 4 of above-mentioned pre-amplifying stage polarization and the relevant bundling device 8 of main amplifying stage polarization can pumping general power as required be added to fine quantity or improve the single armed pump power.
As mentioned above, according to linear polarization pulsed optical fibre laser processing unit (plant) of the present invention, can produce the laser of high stability, high light beam quality, and have antireflection light function, and low cost of manufacture.
Under above-mentioned instruction of the present invention; those skilled in the art can carry out various improvement and distortion on the basis of the foregoing description; and these improvement and distortion; all drop in protection scope of the present invention; it will be understood by those skilled in the art that the just better explanation of above-mentioned specific descriptions purpose of the present invention, protection scope of the present invention is limited by claim and equivalent thereof; any change and distortion in this scope all drops within protection scope of the present invention.
Claims (5)
1. linear polarization pulsed optical fibre laser processing unit (plant) comprises:
The linear polarization solid state laser is used to produce the linear polarization pulse laser;
A plurality of amplifying stages unit comprises polarization be correlated with relevant bundling device of isolator, pumping source, polarization and double clad polarization maintaining optical fibre respectively, and the linear polarization pulse laser by described linear polarization solid state laser output is amplified; And
Be configured in the relevant collimation of polarization isolator, polarizing beam splitter and λ/4 wave plates of final output one side of described a plurality of amplifying stages unit successively, make and after the relevant collimation of the described polarization of laser process isolator, polarizing beam splitter and λ/4 wave plates through amplifying of the output of described a plurality of amplifying stages unit, be radiated on the work piece, and, the laser that is returned along optical axis by described processed object reflection is through after described λ/4 wave plates, its polarization direction becomes vertical with former polarization direction, thereby is reflected to the direction vertical with optical axis by described polarizing beam splitter.
2. linear polarization pulsed optical fibre laser processing unit (plant) according to claim 1, wherein,
Described linear polarization solid state laser comprises linear polarization solid laser module, beam-expanding collimation mirror, condenser lens and the coupling output optical fibre of configuration successively.
3. linear polarization pulsed optical fibre laser processing unit (plant) according to claim 2, wherein,
Going into of the relevant isolator of polarization of the first order amplifying unit in the coupling output optical fibre of described linear polarization solid state laser and the described a plurality of amplifying stages unit is fine by drawing the welding of awl method to realize mould field coupling.
4. linear polarization pulsed optical fibre laser processing unit (plant) according to claim 1, wherein,
Adopt the fiber end face welding of mould field coupling between described a plurality of amplifying stages unit.
5. linear polarization pulsed optical fibre laser processing unit (plant) according to claim 1, wherein,
The pumping input of the relevant bundling device of polarization of a relevant bundling device of the polarization of the previous amplifying stage unit in described a plurality of amplifying stages unit and a back amplifying stage unit is added to fine quantity or improves the single armed pump power according to needed pumping general power.
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| CN107134714A (en) * | 2016-11-01 | 2017-09-05 | 中国科学院苏州纳米技术与纳米仿生研究所 | Laser beam merging apparatus |
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| EP2788803A4 (en) * | 2011-12-09 | 2015-10-21 | Jds Uniphase Corp | Varying beam parameter product of a laser beam |
| US9250390B2 (en) | 2011-12-09 | 2016-02-02 | Lumentum Operations Llc | Varying beam parameter product of a laser beam |
| US9823422B2 (en) | 2011-12-09 | 2017-11-21 | Lumentum Operations Llc | Varying beam parameter product of a laser beam |
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| CN107134714A (en) * | 2016-11-01 | 2017-09-05 | 中国科学院苏州纳米技术与纳米仿生研究所 | Laser beam merging apparatus |
| CN111697426A (en) * | 2019-03-13 | 2020-09-22 | 中国科学院大连化学物理研究所 | Device for generating frequency comb by adopting sulfur hexafluoride stimulated Raman |
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