CN203218696U

CN203218696U - Laser device

Info

Publication number: CN203218696U
Application number: CN 201320172597
Authority: CN
Inventors: 曹丁象; 王兴龙; 胡国绛; 雷和清; 傅谦; 刘侠
Original assignee: ADVANCED FIBER RESOURCES (ZHUHAI) Ltd
Current assignee: ADVANCED FIBER RESOURCES (ZHUHAI) Ltd
Priority date: 2013-04-08
Filing date: 2013-04-08
Publication date: 2013-09-25
Anticipated expiration: 2023-04-08

Abstract

The utility model provides a laser device, comprising a shell; a laser gain medium which is arranged inside the shell and comprises a top surface, a bottom surface and a pair of side surfaces opposite to each other; a pumping device used for outputting light beams to the laser gain medium and irradiating on the laser gain medium; a cooling fin assembly comprises a first cooling fin and a second cooling fin which are both made of sapphire and respectively contact with the top surface and the bottom surface of the laser gain medium; a cooling device used for cooling the cooling fin assembly; and a laser emitter used for emitting laser into the laser gain medium. By employing the sapphire as the cooling fins, the influence of the thermal deformation on the light beam quality can be reduced; meanwhile, the sapphire has a good optical transparency characteristic so that the light beams of a good quality can be outputted; and the cost of the sapphire is much lower than that of diamond so that the popularization and promotion can be benefited.

Description

Laser

Technical field

The utility model relates to laser, more particularly, relates to and utilizes sapphire as the high-power diode light-pumped solid state laser of cooling fin.

Background technology

Laser is the device that utilizes the stimulated radiation principle that light is amplified in the material that some is stimulated or vibrate and launch, solid state laser then is the laser that utilizes solid state gain medium to be stimulated, solid state laser occupies extremely important status in laser is used at present, can be used for materials processing, laser ranging, laser spectroscopy, laser medicine.Laser chemical industry, laser isotope separation and laser fusion etc.

With reference to Fig. 1, the principle of solid state laser is after utilizing solid crystal to be subjected to pump light irradiation absorption pump optical radiation, has activated the ion of solid crystal, and ion is from ground state ²F _7/2Transit to excitation state ²F _5/2The E2 energy level because the distance B 2 between E0 energy level and the E2 energy level, so this process is called the D2 transition.

Subsequently, because the ion lifetime that is on the E2 energy level is extremely short, so the radiationless excitation state that transits to promptly ²F _5/2The E1 energy level, and from excitation state ²F _5/2The E1 energy level send energy jump to ground state ²F _7/2The E0 energy level, the distance between E1 energy level and the E0 energy level is D1, so be called the D1 transition, makes ion release energy by such transition process.

Yet, because in the solid state laser system, some is converted into heat energy and is deposited on solid state gain medium inside in the pump energy that solid state gain medium absorbs, in case being deposited on medium inside, too much heat energy can cause thermal stress excessive, thereby cause that solid state gain medium bursts, the raising of restriction pump power density, and then the raising of influence output laser energy and repetition rate.

On the other hand, the heat of generation also can cause the appearance of problems such as wavefront distortion, birefringence depolarization, has directly influenced the quality of light beam.Thus, heat management also is a key technology of high power solid state laser.

One piece of article " temperature effect of Yb3+:YAG slab laser and diamond window Cooling Design " at " light laser and the particle beams " magazine the 18th volume the 4th phase (in April, 2006) has disclosed a kind of diamond that utilizes as the solid state laser of cooling window, and its structure chart as shown in Figure 2.The pump energy of the gain medium 22 absorptive pumping light P1 of solid, then laser L1 injects after gain medium 22 energy that afterwards absorption gain mediums 22 send, penetrate laser L2, gain medium 22 can be at the inner heat that produces of medium during this time, need two cooling windows of being formed by diamond 21 this moment, 25 contact with the end face of laser gain module 22 and bottom surface carries out heat conduction, thereby reduce the temperature of gain medium 22, again by four

ooling channels

23,24,26, one end of 27 pairs of cooling windows cools off, thereby take away heat, guarantee that laser operates normally.

But, because the material that the cooling window uses is diamond, and present adamantine processing technology has determined that its optical transparence is poor, can influence the quality of light beam, simultaneously because adamantine price is generally higher, make product cost increase and be unfavorable for promoting, also can cause development cost to rise simultaneously.

Summary of the invention

The purpose of this utility model provides a kind of sapphire that utilizes as the laser of the efficient cooling fin of material.

In order to realize above-mentioned purpose, the utility model provides a kind of laser, comprises housing, is provided with gain medium in the housing, and gain medium has an end face, a bottom surface and a pair of relative side; Pump arrangement, pump arrangement is to gain medium output beam and radiation laser gain media; Cooling fin assembly, cooling fin assembly comprise first cooling fin and second cooling fin, and first cooling fin and second cooling fin contact with end face, the bottom surface of gain medium respectively; Cooling device, cooling device cools off the cooling fin assembly; Generating laser, laser generator is injected laser to gain medium, and wherein, first cooling fin and second cooling fin are made up of sapphire.

By such scheme as seen, sapphire thermal conductivity at normal temperatures is about 40W/mK, under the condition of low temperature (77K), sapphire thermal conductivity can also be up to 1000 W/mK, so utilize sapphire can rapidly the waste heat of gain medium be taken away as the cooling fin assembly of gain medium, because sapphire has the good optical transparent characteristic, can export good beam quality simultaneously, sapphire cost is much lower with respect to the diamond cost, is conducive to popularize.Adopt two-sided sapphire cooling fin assembly to make that the efficient of cooling laser gain media is higher.

A preferred scheme is, gain medium is by yttrium aluminum garnet crystal with ytterbium doping, and namely the Yb:YAG crystal is formed.

Therefore, adopt yttrium aluminum garnet crystal with ytterbium doping as gain medium, it is wide that yttrium aluminum garnet crystal with ytterbium doping has absorption band, upper level lifetime is long, the quantum efficiency advantages of higher, and because above-mentioned sapphire refractive index and the refractive index of yttrium aluminum garnet crystal with ytterbium doping are close, make to guarantee that the reflection loss of contact-making surface is very little, make laser beam have better quality.

A preferred scheme is, generating laser is installed in the gain medium top face and to the laser of gain medium emission perpendicular to the end face of gain medium.

Therefore the laser of the line chamber that the employing said structure is made has advantages such as compact conformation, the life-span is long, system is simple.

A preferred scheme is, pump arrangement has two semiconductor lasers, and two semiconductor laser installing are in the gain medium top face and be installed in the both sides that are positioned at generating laser respectively, and semiconductor laser is launched pump light to gain medium.

Therefore, adopt the said structure pump arrangement can make uniform heavy caliber pumping, utilize bigbore pumping to export the more pump energy of multipotency, make the laser of emission have higher power.

A preferred scheme is, cooling device comprises first ooling channel and second ooling channel, in first ooling channel and second ooling channel cooling agent is housed all, cooling agent in first ooling channel contacts with the other surface of a side of first cooling fin and second cooling fin, and the cooling agent in second ooling channel contacts with the other surface of the opposite side of first cooling fin and second cooling fin.

Therefore, utilize the cooling agent in above-mentioned two ooling channels that cooling fin is taken away at the used heat that gain medium absorbs, the structure by this one makes the cooling device compact conformation, is convenient to install.

A preferred scheme is that cooling agent is water.

Therefore, specific heat of water holds relatively large, homogenous quantities with the water of initial temperature and other flowing fluid ratios, absorb slow that identical heat coolant-temperature gage raises, so be not easy to reach boiling point, and the pollution-free nothing corrosion of water, utilize water can efficiently contamination-freely the used heat of cooling fin be taken away rapidly as cooling agent.

A preferred scheme is, first cooling fin and second cooling fin are working surface in end face and the bottom surface facing surfaces of gain medium, surface beyond the working surface of first cooling fin and second cooling fin is cooling surface, and cooling agent contacts with cooling surface.

Therefore, can use normally in order to guarantee laser, thus there are not current to flow through at working surface, because current when flowing through the cooling fin surface, can influence the stability of laser inevitably.

Description of drawings

Fig. 1 is gain medium level structure schematic diagram.

Fig. 2 is the structure principle chart of a kind of laser of the prior art.

Fig. 3 is the structure principle chart of the utility model embodiment.

The utility model is described in further detail below in conjunction with drawings and Examples.

Embodiment

With reference to Fig. 3, Fig. 3 is the structure principle chart of the utility model embodiment laser.Laser comprises housing, be provided with gain medium 38 in the housing, gain medium 38 is mixed the ytterbium yttrium-aluminium-garnet by Yb:YAG() crystal forms, the end face of gain medium 38 and bottom surface contact with

cooling fin

36,37 respectively, two

cooling fins

36,37 are formed the cooling fin assemblies, and cooling

fin

36,37 is by being made by sapphire.Also be provided with cooling device in the housing, cooling device comprises

ooling channel

34,35, cooling agent is housed in the ooling channel, cooling agent is water, direct and the cooling fin 36 of water, the surface contact of 37 1 ends, wherein cooling fin 36 has the working face F1 relative with the gain medium end face, cooling fin 37 also has the working face F2 relative with the gain medium bottom surface, the surface of cooling fin 36 beyond working face F1 has cooling surface F3, F4, F9, F10, same, the surface of cooling fin 37 beyond working face F2 has cooling surface F5, F6, F7, F8, cooling agent in the ooling channel 34 and cooling surface F3, F4, F5, F6 contacts, the cooling agent in the ooling channel 35 and cooling surface F7, F8, F9, F10 contacts.

Be provided with generating laser 31 above inherent gain medium 38 end faces of laser housing, generating laser 31 is launched laser L3 to gain medium 38 perpendicular to end face.

Also be provided with pump arrangement in the laser housing, pump arrangement comprises

semiconductor laser

32,33, above gain medium end face 38 and in a side of generating laser 31, be provided with semiconductor laser 32, and above gain medium end face 38 and at the opposite side of generating laser 31, be provided with semiconductor laser 33.When

semiconductor laser

32,33 to gain medium output pump light P2, P3, the exciting back that the ion in the gain medium 38 is subjected to pump light takes place to the excitation state transition, transits to ground state from excitation state again subsequently, during produce emittance.Generating laser emission this moment laser L3 sees through cooling fin 36 and enters into gain medium 38, and laser L3 has more high-power laser L4 through cooling fin 37 ejaculations after having absorbed emittance.

By the above embodiments effectively by sapphire as cooling fin, at pumping output pump light in the gain medium, gain medium is understood some in the absorptive pumping energy energy is converted into heat energy and is deposited on gain medium inside, by the cooling fin of being formed by sapphire end face and the bottom surface of gain medium are cooled off, can guarantee in time the used heat that is deposited on gain medium inside can be taken away to prevent to burst on the one hand, extract used heat from end face on the other hand, help to set up axial one dimension thermal gradient, thereby reduce the transverse temperature gradient, to reduce the heat deformity to the influence of beam quality.Take away heat by the cooling agent in the ooling channel of cooling device again, make whole system to operate normally.

Claims

1. laser comprises housing, is provided with in the housing

Gain medium, described gain medium have an end face, a bottom surface and a pair of side;

Pump arrangement, described pump arrangement is to described gain medium output beam and radiation laser gain media;

The cooling fin assembly, described cooling fin assembly comprises first cooling fin and second cooling fin, described first cooling fin and described second cooling fin contact with end face and the bottom surface of described gain medium respectively;

Cooling device, described cooling device cools off described cooling fin assembly;

Generating laser, described laser generator is injected laser to described gain medium;

It is characterized in that:

Described first cooling fin and described second cooling fin are made up of sapphire.

2. laser according to claim 1 is characterized in that:

Described gain medium is made up of yttrium aluminum garnet crystal with ytterbium doping.

3. laser according to claim 1 is characterized in that:

Described generating laser is installed in described gain medium top face and to the laser of described gain medium emission perpendicular to the end face of described gain medium.

4. according to each described laser of claim 1 to 3, it is characterized in that:

Described pump arrangement has two semiconductor lasers, and described two semiconductor laser installing are in described gain medium top face and be installed in the both sides that are positioned at described generating laser respectively.

5. laser according to claim 1 is characterized in that:

Described cooling device comprises first ooling channel and second ooling channel, in described first ooling channel and described second ooling channel cooling agent is housed all, cooling agent in described first ooling channel contacts with the other surface of a side of described first cooling fin and second cooling fin, and the cooling agent in described second ooling channel contacts with the other surface of the opposite side of described first cooling fin and second cooling fin.

6. laser according to claim 5 is characterized in that:

Described cooling agent is water.

7. according to claim 5 or 6 each described lasers, it is characterized in that:

Described first cooling fin and described second cooling fin are working surface in end face and the bottom surface facing surfaces of described gain medium, surface beyond the described working surface of described first cooling fin and described second cooling fin is cooling surface, and described cooling agent contacts with described cooling surface.