CN101005191A - Method and its device for detecting high energy semiconductor laser divergence angle - Google Patents

Abstract

Using geometric characteristics of outer margin curves of two light spots at different distances along direction of beam transmission, the disclosed method obtains divergence angle of laser. Through rotational scanning detection, concentric placed two light detectors perpendicular to each other obtain outer margin curves. Multiple optical fibers are distributed on the said light detector evenly. The disclosed device is composed of drive power supply, cooling water platform, cooling water circulation system, 4D traveling platform, electrical motor set, drive, data acquisition module, and PC etc. The light-receiving module includes light detectors. The light-receiving module, data acquisition module, and PC are connected electrically. The invention solves issue of test error caused by regarding face radiation of area array laser as spot light source so as to avoid damaging and burning detector caused by too large power of laser. Advantages are: accurate and reliable.

Description

High energy semiconductor laser divergence angle method of testing and device thereof

Technical field

The present invention relates to the high energy semiconductor laser beam quality detects.A kind of method of measurement of high energy semiconductor laser divergence angle the invention still further relates to and realizes the used device of said method in more detail.

Background technology

The high energy semiconductor laser beam divergence angle is an important indicator that characterizes laser beam quality, and the accurate measurement of beam divergence angle is the quality that is related to its colimated light system design, influences its key in application.In the semiconductor laser beam divergence angle measurement, that generally uses is main with CCD camera mensuration, cantilever beam detector scanning method etc. at present.There are the following problems when yet these methods are used for measuring high power laser: the one, and existing method of testing all is the luminous point-source of light of directly being used as of the face of high energy face battle array laser, the test error that can cause like this; The 2nd, if use existing method of testing direct detection can make CCD and detector saturated or burn, the shape that can change hot spot is again surveyed in decay earlier again, has a strong impact on the accuracy of measurement.We have proposed a kind of new high energy semiconductor laser divergence angle method of testing and device thereof at these problems.

Summary of the invention

The object of the present invention is to provide a kind of method of testing of high energy semiconductor laser divergence angle, overcome the shortcoming and defect of prior art, have accurate, stable, reliable and high-precision advantage.

Another object of the present invention is to provide a kind of device of high energy semiconductor laser divergence angle test.

Technical scheme of the present invention is, a kind of high energy semiconductor laser divergence angle method of testing, geometric properties with direction of beam propagation different distance place two hot spot outer rims curve is tried to achieve laser divergence angle, hot spot outer rim curve is by two vertical mutually, placements with one heart, above evenly the rotation sweep of the light probe of distribution multifiber survey and obtain, another termination photo-detector of optical fiber comprises the steps:

(1) make measured laser device 1 center be in the center of optical fiber receive module 8 with perusal;

(2) start driving power 2 and cooling water recirculation system 4, make measured laser device 1 normally luminous;

(3) X-direction is to the heart: the curve of light distribution of surveying the X-direction that obtains measured laser device 1, try to achieve the position coordinates of peak of curve point and the distance L 3 between optical fiber receive module 8 central points, manual adjustments makes four-dimensional travelling carriage 5 at X-direction displacement L3, finishes horizontal direction to the heart;

(4) Y direction is to the heart: principle is with (3), and direction is a Y-axis, and other is identical;

(5) Z-direction is to the heart: finished jointly in the mobile regulatory function of Z-direction with around the rotation regulatory function of Y-axis by four-dimensional travelling carriage 5;

(6) start stepping motor 11 and rotate from the fixed position, change 1.8 degree after, of short duration wait, data collecting module collected is to two groups of test datas, and passes to PC 14, PC 14 receives, preserves test data;

(7) repeat above-mentioned steps (5), finish 180 degree up to stepping motor 11 and rotate;

(8) PC 14 receives 200 groups of the test datas that obtain by optical fiber receive module, to every group of test data curve fit, obtains 200 of the corresponding curves of light distribution;

(9) try to achieve two hot spot marginal points according to every curve of light distribution, can obtain the hot spot marginal point of 400 diverse locations altogether;

(10), obtain two hot spot outer rim curves at beam Propagation different distance place to hot spot marginal point curve fit;

(10) try to achieve the major axis and the minor axis of two hot spot outer rim curves respectively;

(11) two major axis are depicted in the same coordinate system system, two minor axises are depicted in another coordinate system, try to achieve the fast axle and the slow axis angle of divergence of measured laser device 1.

Described measured laser device 1 is meant the high energy semiconductor laser that need carry out angle of divergence test.Optical fiber receive module 8 is the devices that are used to receive and survey light.Driving power 2 is the drivers that are used to drive measured laser device 1 operate as normal, can adopt the high energy semiconductor laser driving power of commercialization.As the high energy of productions such as Beijing Ai Keyiou Electro-optical Technology, INC. (US) 62 Martin Road, Concord, Massachusetts 017, Hangzhou Reliable Instrument Factory continuously/pulse laser driving power or adopt discrete component to build.The cooling water recirculation system 4 measured laser device 1 that is used to freeze damages because of temperature is too high when avoiding 1 work of measured laser device or burns, and can select semiconductor cooler or water-cooling system for use.Load measured laser device 1 on the four-dimensional travelling carriage 5, be used for 8 pairs of hearts of measured laser device 1 and optical fiber receive module and regulate.Stepping motor 11 can drive optical fiber receive module 8 and rotate, thus the light distribution of the measured laser device 1 of the whole beam plane of scanning probe.The curve of light distribution is meant that the luminous beam of measured laser device 1 is transferred to a distance, and the optical fiber receive module of being placed at an angle 8 is surveyed the light intensity curve that obtains, and is the bell jar type in theory.The hot spot edge is meant that laser beam is transferred to a certain distance, the set of the unglazed separation of all light on the whole circumference.Be that light intensity value is the 1/e of largest light intensity on the curve of light distribution of all angles of receiving of a certain distance ²The time location point set.Data acquisition module 13 is used for the reception of analog signal and converts digital signal to, can adopt the universal data collection card to realize.The series data capture card produced of National Instruments company for example, or utilize processor (single-chip microcomputer), analog to digital converter to build data acquisition system.Data processing and demonstration are meant in computer and realize that by software programmings such as VB, VC described Presentation Function comprises: the tabulation demonstration of every group of test data, the demonstration of every light intensity curve, the demonstration of two hot spot outer rim curves, the demonstration of angle of divergence result of calculation etc.

Realize the device of high energy semiconductor laser divergence angle method of testing, comprise: driving power 2, cooling water platform 3, cooling water recirculation system 4, four-dimensional travelling carriage 5, group of motors 6, driver 7, optical fiber receive module 8, stepping motor 12, driver 13, data acquisition module 14 and PC 15, measured laser device 1 is placed on the water-cooled platform 3, water-cooled platform 3 is placed on the four-dimensional travelling carriage 5, water-cooled platform 3 is connected with hydrologic cycle cooling system 4 by water pipe, four-dimensional travelling carriage 5 and group of motors 6 mechanical connections, group of motors 6 is electrically connected with driver 7, driving power 5 is electrically connected with measured laser device 1, optical fiber receive module 8 is made up of light probe 9 and light probe 10, light probe 9 and light probe 10 are concentric, the vertical placement is by connector 11 mechanical connections; Light probe 9 is connected with stepping motor 12 solid mechanical, and stepping motor 12 is electrically connected with driver 13, and optical fiber receive module 8, data acquisition module 14, computer 15 are electrically connected successively, and driver 7, driver 13 are electrically connected with computer 15 respectively.Described light probe 9 is made up of semicircular ring structure 16, optical fiber 17, photodiode 18; semicircular ring structure 16 is connected with optical fiber 17; optical fiber 17 angle intervals＜5; optical fiber 17 is connected with photodiode 18 by standard fiber FC interface; semicircular ring structure 16 is heat-resisting resistant to elevated temperatures organic resin material; optical fiber 17 is single mode or multimode fiber, and light probe 10 comprises: semicircular ring structure 19, optical fiber 20, photodiode 21.Described light probe 10 and the difference of light probe 9 are that the radius of the semicircular ring structure 16 of two probes and semicircular ring structure 19 is different, and other compositions are all identical.

Principle of the present invention is: measurand is the high energy surface array semiconductor laser, and its luminous geometry mostly is rectangle, and is slightly different with the point light source light-emitting of common lasers.At these characteristics, propose to adopt two vertical mutually, concentric placements, above evenly the rotation sweep detecting light beam of the optical fiber receive module formed of the light probe of distribution multifiber (another termination photo-detector of optical fiber) propagate into the light intensity of different distance, thereby try to achieve the method for the angle of divergence.Concrete test philosophy is as follows:

When optical fiber receive module is in a certain position when motionless, the light that the line source of a certain direction of only measured laser device that light probe receives and detects sends, light receives and is transferred to corresponding detector by being distributed in the structural optical fiber of semicircular ring, the angle position of every optical fiber is certain, the light intensity that correspondence detects is certain, after data acquisition and conversion, can obtain a curve of light distribution.Light distribution meets the bell jar curve in theory.Angle of divergence definition it has been generally acknowledged that, as the 1/e of light intensity attenuation to largest light intensity ²The time be that the edge laser beam of hot spot has the unglazed separation of light in this position.Optical fiber receive module drives the backspin turnback at stepping motor, gathers a secondary data every 1.8 degrees of data acquisition modules, and draws a curve of light distribution.The unglazed separation of light is arranged when obtaining this angle according to curve by said method.When inswept whole the battle array laser of light probe, the laser beam that can obtain the measured laser device has a unglazed separation of light on whole, these points are fitted, and can obtain the hot spot outer rim curve of this position.Two light probes can obtain two hot spot outer rim curves.Desirable hot spot outer rim curve is oval.According to oval geometrical feature, the minor axis of two ellipses and major axis can be asked.Two minor axises are described in the same coordinate system, and two major axis are described in another coordinate system, according to geometrical relationship, can be obtained the slow axis angle of divergence and the fast axle angle of divergence of measured laser respectively by two minor axises and two major axis.

The invention has the beneficial effects as follows:

(1) the present invention utilizes the geometric properties of direction of beam propagation different distance place two hot spot outer rims curve to try to achieve laser divergence angle, and this has solved the luminous luminous test error that causes of point of directly being used as point-source of light of the face of face battle array laser.

(2) use optical fiber to collect light signal in the inventive method, because the internal diameter of optical fiber is very little, it is limited to receive light intensity, and optical fiber itself receives and transmission light is not limited by light intensity, therefore, adopt and thisly to receive by optical fiber that the method for passing to photo-detector has again solved common CCD camera mensuration or cantilever beam detector scanning method limits the problem that can not test the high-energy laser angle of divergence because of being subjected to light intensity.

(3) the inventive method is come the exploring laser light hot spot by fiber array, can not change the shape of laser, and the method for afterwards surveying that decays earlier during therefore with the traditional measurement high power semiconductor lasers angle of divergence is compared, and has the advantage of accuracy.

(4) adopt semicircular structure can measure the multiple spot light intensity simultaneously among the present invention, make to measure to have accurate, stable, reliable advantage.

(5) cost of each assembly of device of the present invention is lower, so the cost of single unit system is also relatively low, again because the structure of this device is comparatively simple, so the production assembling is more or less freely, uses operation also more convenient.

Description of drawings

The present invention is described in further detail below in conjunction with drawings and Examples.

Fig. 1 shows basic test principle of the present invention.

Fig. 2 is a high energy semiconductor laser divergence angle testing apparatus structural representation of the present invention;

Fig. 3 is the structural representation of light probe 9 shown in Figure 2;

Fig. 4 is the structural representation of light probe 10 shown in Figure 2;

Fig. 5 be optical fiber receive module 8 shown in Figure 2 when stepping motor 12 rotational angle theta=0 ° light probe 9 and the semicircular ring structure 16 of light probe 10 correspondences and relative position schematic diagram of 19;

Fig. 6 be optical fiber receive module 8 shown in Figure 2 when stepping motor 12 rotational angle theta=90 ° light probe 9 and the semicircular ring structure 16 of light probe 10 correspondences and relative position schematic diagram of 19;

Fig. 7 light intensity curve distribution map that to be light probe 9 shown in Figure 2 survey when stepping motor 11 rotational angle theta=0 °

The light intensity curve distribution map that Fig. 8 surveyed when being light probe 9 shown in Figure 2 in stepping motor 11 rotational angle theta=0 °, θ=45 °, θ=90 °

Fig. 9 is the key diagram that obtains hot spot outer rim curve according to the curve of light distribution shown in Figure 8;

Figure 10 is the key diagram that is obtained the fast axle of the laser angle of divergence by the major axis of two hot spot outer rim curves;

Figure 11 is that 1 pair of heart of optical fiber receive module 8 shown in Figure 2 and measured laser device is regulated preceding relative position presentation graphs in X-direction;

(be used for optical fiber receive module 8 and in X-axis and Y-axis both direction the heart regulated explanation) with measured laser device 1

Figure 12 is measured laser device 1 shown in Figure 11 two curve of light distribution comparison diagrams that semicircular ring structure 19 is surveyed before and after X-direction is regulated the heart;

(be used for optical fiber receive module 8 and in X-axis and Y-axis both direction the heart regulated explanation) with measured laser device 1

Figure 13 is that 1 pair of heart of optical fiber receive module 8 shown in Figure 2 and measured laser device is regulated preceding relative position presentation graphs in Z-direction; (measured laser device 1 is in the outside at optical fiber receive module 8 centers)

Figure 14 is that 1 pair of heart of optical fiber receive module 8 shown in Figure 2 and measured laser device is regulated preceding relative position presentation graphs in Z-direction; (measured laser device 1 is in the inboard at optical fiber receive module 8 centers)

Figure 15 is that 1 pair of heart of optical fiber receive module 8 shown in Figure 2 and measured laser device is regulated the relative position presentation graphs of back in Z-direction;

Figure 16 is the curve of light distribution figure that 9 actual detection of light probe shown in Fig. 2 obtain;

Figure 17 is the curve of light distribution figure that 10 actual detection of light probe shown in Fig. 2 obtain;

Figure 18 is Figure 13 hot spot outer rim curve chart corresponding with Figure 14 and the test result figure of the angle of divergence.

Among the figure, 1, the measured laser device, 2, driving power, 3, the cooling water platform, 4, cooling water recirculation system, 5, four-dimensional travelling carriage, 6, group of motors, 7, driver, 8, optical fiber receive module, 9, light probe, 10, light probe, 11, connector, 12, stepping motor, 13, driver, 14, data acquisition module, 15, PC, 16, circular ring structure, 17, optical fiber, 18, photodetector, 19, semicircular ring structure, 20, optical fiber, 21, photodetector.

Embodiment

Fig. 1 shows basic test principle of the present invention.In divergent angle test method in the past, usually be the laser equivalence point-source of light, therefore, only with a hot spot of a certain distance of distance laser-as the hot spot A of L1 distance among Fig. 1, just can obtain the angle of divergence of laser, the angle of divergence of trying to achieve like this such as the α among Fig. 1.The present invention is the angle of divergence that laser is asked on the basis with the geometric properties that laser beam is transferred to two hot spot outer rim curves at different distance place.As shown in Figure 1, be that the angle of divergence is asked on the basis with the hot spot A and the hot spot B at distance lasers L1 and L2 two places, this angle can be expressed as β among the figure.Obviously, compare with α, β has considered the influence of the light-emitting area size of laser to the angle of divergence own, the true angle of divergence of energy more accurate representation laser.

Fig. 2 shows concrete structure of the present invention, as seen from Figure 2, this high energy semiconductor laser divergence angle testing apparatus comprises: driving power 2, cooling water platform 3, cooling water recirculation system 4, four-dimensional travelling carriage 5, group of motors 6, driver 7, optical fiber receive module 8 (being made up of light probe 9, light probe 10 and connector 11), stepping motor 12; Driver 13; Data acquisition module 14; PC 15.Measured laser device 1 is placed on the water-cooled platform 3, water-cooled horizontal stand 3 is placed on the four-dimensional travelling carriage 5, water-cooled horizontal stand 3 is connected with hydrologic cycle cooling system 4 by water pipe, four-dimensional travelling carriage 5 is electrically connected with driver 7 with group of motors 6 mechanical connections, group of motors 6, driving power 5 is electrically connected with the measured laser device, optical fiber receive module 8 is made up of light probe 9, light probe 10 and connector 11, light probe 9 and light probe 10 are by connector 11 mechanical connections, and light probe 9 is connected with stepping motor 12 solid mechanical; Stepping motor 12 is electrically connected with driver 13; Light probe 9 and light probe 10 are electrically connected successively with data acquisition module 14, computer 15.Driver 7, driver 13 are electrically connected with computer 15 respectively.Described driving power 2 is used to drive measured laser device 1 operate as normal; Described cooling water platform 3 and cooling water recirculation system 4 are used to cool off measured laser device 1, avoid the measured laser device to damage because of working temperature is too high or burn; Described four-dimensional travelling carriage 5 can be three-dimensional the translation fine setting and the rotary fine adjustment of one dimension, be used for 8 pairs of hearts of measured laser device 1 and optical fiber receive module and regulate; Described group of motors 6 is used to drive the automatic adjusting that four-dimensional travelling carriage 5 is done D translation and one dimension rotation; Described driver 7 is used for drive motors group 6; Described optical fiber receive module 8 is used for measured laser device 1 luminous reception and detection, and carry out opto-electronic conversion, form by light probe 9, light probe 10 and connector 11, light probe 9 and light probe 10 are concentric, the vertical placement, and be connected to a fixed by connector 11, the structure of described light probe 9 and light probe 10 is as shown in Figure 3, Figure 4.

Fig. 3 shows the concrete structure of light probe described in the present invention 9, as seen from Figure 3, light probe 9 comprises semicircular ring structure 16, optical fiber 17, photodiode 18, semicircular ring structure 16 is connected with the multifiber 17 at certain angle interval (＜5 °), and optical fiber 17 is connected with photodiode 18 by standard fiber FC interface.Semicircular ring structure 16 is heat-resisting resistant to elevated temperatures organic resin material, and internal diameter is 450mm, and external diameter is 485mm, and ring width is 35mm.

Fig. 4 shows the concrete structure of light probe described in the present invention 10.Described light probe 10 also comprises: semicircular ring structure 19, optical fiber 20, photodiode 21.Light probe 10 and the difference of light probe 9 are that the semicircular ring structure 16 of two probes is different with 19 radius, and the internal diameter of the semicircular ring structure 19 of probe 10 is 350mm, and external diameter is 385mm, and other compositions are all identical; Described stepping motor 12 can drive optical fiber receive module 8 around rotating with the laser 1 output beam direction of propagation, is used for the light distribution in full week of scanning light beam plane; Described data acquisition module 14 is used for collection, the digital-to-analogue conversion of the dateout of light probe 9 and light probe 10 photodiodes 18 and 21.Every rotations 1.8 degree of stepping motor 12, data acquisition module 14 is gathered a secondary data, and sends computer 15 to by USB interface and finish data processing and Presentation Function.Described data acquisition module 14 mainly is made up of single-chip microcomputer, AD conversion chip, sampling amplifier etc.Concrete model is: single-chip microcomputer adopts the high-performance processor 7045 of Hitachi, Ltd; The AD chip adopts 12 AD:Max1246 of 4 passages of MAX company; The sampling amplifier model is: INA128uA.Comprise 20 AD in the described as required data acquisition module 8.Data processing and the Presentation Function finished on the described computer 15 are finished by VB software, after stepping motor 12 turns over 180 degree, photodiode 18 and 21 data are 200 groups in light probe 9 that the VB test program receives and the light probe 10, described VB software Presentation Function comprises: the tabulation of every group of test data shows, the demonstration of every light intensity curve, article two, the demonstration of hot spot outer rim curve, the demonstration of angle of divergence result of calculation etc., wherein, the light intensity curve of light probe 9 and light probe 10 is presented at respectively in two coordinate systems, can freely select to show simultaneously one or more curve in each coordinate system.Fig. 5 and Fig. 6 show when stepping motor 12 forwards different angles among Fig. 2, light probe 9 and the semicircular ring structure 16 of light probe 10 correspondences and 19 relative position, and their connected mode.The front view of semicircular ring structure 16 and 19 relative positions when the front view of semicircular ring structure 16 and 19 relative positions when Fig. 5 is stepping motor 12 rotational angle theta=0 °, Fig. 6 are stepping motor 12 rotational angle theta=90 °.Semicircular ring structure 16 and 19 (also being light probe 9 and light probe 10) is vertical, concentric as can be seen from two width of cloth figure, and fixedly connected by connector 11, becomes one.Simultaneously, semicircular ring structure 16 (also being light probe 9) is fixedlyed connected with stepping motor 12.Guaranteed that like this light probe 9, light probe 10 and connector 11 all are one, have fixing can relative position.And rotate with stepping motor 12 simultaneously.

Fig. 3, Fig. 7, Fig. 8, Fig. 9 show the concrete procurement process of the outer rim of hot spot described in the present invention curve.Hot spot outer rim curve is surveyed acquisition by the light probe 9 of above-mentioned introduction and the rotation sweep of light probe 10.As Fig. 1, hot spot B is surveyed by the rotation sweep of the semicircular ring structure 16 on the light probe among the figure 9 and obtains, and hot spot A obtains (not drawing among semicircular ring structure 19 Fig. 1) by the semicircular ring structure on the light probe 10 19.With hot spot B is the concrete procurement process of example explanation hot spot outer rim curve.

Suppose initial testing, promptly during the anglec of rotation θ of stepping motor 12=0 °, the semicircular ring structure 16 on the light probe 9 is in the perpendicular, promptly among Fig. 1 in the XZ plane.At this moment, the light that semicircular ring structure 16 on the light probe 9 receives and detects is equivalent to the light that the line source of X-direction sends on the face battle array laser among the figure, light receives and is transferred to corresponding photodetector by the optical fiber that is distributed on the semicircular ring structure 16, every optical fiber endpoint location (being test point) and the light intensity of surveying are known, as shown in Figure 3, with the F1 point is the example explanation, the F1 point is the end points of an optical fiber F wherein on the semicircular ring structure 16, optical fiber F and Z axle clamp angle are λ, the internal diameter of the semicircular ring structure 16 on the light probe 9 is 450mm, then the F1 point can be asked from D to the Z wheelbase, for:

D＝450*Cosλ；

With the optical fiber end points to the Z wheelbase from being abscissa, be that ordinate is drawn coordinate system as shown in Figure 7 with the test point light intensity, wherein F1 ' is F1 corresponding point in coordinate system.In like manner, the test point of every optical fiber correspondence on the semicircular ring structure 16 on the light probe 9 all with (test point position, light intensity) for two-dimensional coordinate is depicted in the coordinate system, then the light distribution trend of the laser that the semicircular ring structure 16 on the light probe 9 surveys is represented in the distribution of coordinate system mid point in the XZ plane.After these points are carried out data processing and curve fit, can obtain a curve of light distribution, i.e. this moment, the laser beam curve of light distribution that stepping motor 12 anglec of rotation θ=0 record when ° making the semicircular ring structure 16 on the light probe 9 be in the vertical XZ plane.If the 1/e of light intensity attenuation to largest light intensity ²The time the position as the edge of hot spot.So, 2 of S1, S2 are a pair of hot spot marginal points of the hot spot B that obtains during in stepping motor 12 anglec of rotation θ=0 ° of semicircular ring structure 16 on the light probe 9 among the figure, the S1 ' in the corresponding diagram 7 on X ' axle, S2 '.

Stepping motor 12 drives light probe 9 rotations, and hypothesis light probe 9 relative hot spot B are that X ' Y ' scans on the plane clockwise among Fig. 1.In the rotary course, gather a secondary data, try to achieve a curve of light distribution, obtain a pair of hot spot marginal point on the hot spot B simultaneously every 1.8 ° of data acquisition modules 14.When stepping motor 12 turns over 180 °, light probe 9 inswept whole battle array lasers obtain 100 curves of light distribution, obtain 100 pairs of hot spot marginal points of hot spot B on whole circumference.With three light intensity curves wherein is the example explanation, and as shown in Figure 8, they are respectively stepping motor 11 rotational angle theta=0 °, records when θ=45 °, θ=90 °.Three pairs of hot spot marginal points on the hot spot B that tries to achieve according to three curves are respectively S1, S2, P1, P2 and Q1, Q2.The following describes the process that obtains hot spot B according to these hot spot marginal points.

Coordinate system is represented X ' Y ' plane, hot spot B place among Fig. 9.Three couples of hot spot marginal point S1, S2, P1, P2 and Q1, Q2 are depicted in respectively in the coordinate system, and then as Fig. 8 and Fig. 9, the corresponding θ of S1, S2=0 ° is S1 ', the S2 ' on X ' axle, and distance L between S1 ', the S2 ' _{S1 ' S2 '}Equal distance L between S1, the S2 _S1s2P1 ', P2 ' during the corresponding θ of P1, P2=45 ° on the axis, and ${\mathrm{<figure-callout\; id="1"\; label="L\; P"\; filenames="A20061013501800171.png,A20061013501800181.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{P_{}}^{}}=L_{P_1{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">P</figure-callout>}}_2}$ Q1, Q2 corresponding Q1 ', Q2 ', ${\mathrm{<figure-callout\; id="1"\; label="L\; Q"\; filenames="A20061013501800171.png,A20061013501800181.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{Q_{}}^{}}=L_{Q_1{\mathrm{<figure-callout\; id="2"\; label="Q"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">Q</figure-callout>}}_2}$ 。In like manner, other hot spot marginal points are depicted in the coordinate system, these point data processing and curve fit are just obtained hot spot B.And can try to achieve major axis and the minor axis of B, as the N1 ' N2 ' among Fig. 9 and U1 ' U2 '.

In like manner, be that the basis can obtain hot spot A with the rotated detection of the semicircular ring structure 19 on the light probe 10, and its long and short axle, as the medium and small ellipse of Fig. 9.

Figure 10 shows the computational process of the angle of divergence described in the present invention.As Figure 10, wherein, N1 ' N2 ' represents hot spot B major axis, and V1 ' V2 ' represents hot spot A major axis.Semicircle C1 represents the inside radius of the semicircular ring structure 16 on the light probe 9, and C2 represents the inside radius of the semicircular ring structure 19 on the light probe 10.N1 ', N2 ' and V1 ', V2 ' are respectively the hot spot marginal points of hot spot B and hot spot A, and they lay respectively on C1 and the C2, as Figure 10.And have: LON2 '=450mm; LOV2 '=350mm.Have as geometrical relationship among the figure

$\left\{\begin{array}{c}\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}}{L_{\mathrm{KF}}-K_{\mathrm{EF}}}=\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}}{L_{\mathrm{KF}}};\\ L_{\mathrm{EF}}=\sqrt{{450}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}}-\sqrt{{350}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}};\end{array}\right.$

So:

$L_{\mathrm{KF}}=\frac{(\sqrt{{450}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}}-\sqrt{{350}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}})\&times;{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}}{{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}-{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}};$

Then:

$\mathrm{\&delta;}=2\mathrm{arctg}\left(\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}-{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}}{\sqrt{{450}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}}-\sqrt{{350}^2-{\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}}}\right);$

Wherein:

${\mathrm{<figure-callout\; id="2"\; label="L\; FN"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{FN}}_{}}^{}}=\frac{{\mathrm{<figure-callout\; id="1"\; label="L\; N"\; filenames="A20061013501800171.png,A20061013501800181.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{N_{}}^{}}}{2},$ ${\mathrm{<figure-callout\; id="2"\; label="L\; EV"\; filenames="A20061013501800161.png,A20061013501800191.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{{\mathrm{EV}}_{}}^{}}=\frac{{\mathrm{<figure-callout\; id="1"\; label="L\; V"\; filenames="A20061013501800171.png,A20061013501800181.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{V_{}}^{}}}{2};$

By top formula, the fast axle angle of divergence δ of laser can ask.The slow axis angle of divergence of laser is obtained according to same method.

Figure 11, Figure 12, Figure 13, Figure 14 and Figure 15 show heart control method, as mentioned above, and the 1/e of largest light intensity ²The position at place is as the hot spot marginal point, if the luminescence center of the center of circle of light probe 9 and light probe 10 and measured laser device 1 can not be corresponding, in the time of can causing light probe 9 and light probe 10 to rotate to a certain position, the peak point of the curve of light distribution of measuring can influence the accuracy of the hot spot marginal point of trying to achieve like this less than the luminous largest light intensity of measured laser device 1 reality.The center alignment method that the present invention adopts is as follows:

At first make measured laser device 1 center roughly be in the center of light probe 9 and light probe 10, start driving power 2, make measured laser device 1 luminous with perusal; Next carries out X-direction the heart is regulated, as Figure 11, the relative position of the semicircular ring structure 19 that the semicircular ring structure 16 that measured laser device 1 and light probe 9 are corresponding before supposing to regulate and light probe 10 are corresponding as shown in figure 11, O ₁Be the center of measured laser device 1, O ₂Be the center of semicircular ring structure 1, O ₃Be the center of semicircular ring structure 2, by light probe 10, obtain curve of light distribution C3, as shown in Figure 12, transverse axis is represented each test point (each root optical fiber end points on the semicircular ring structure 16) to the distance of Z axle among the figure, and the longitudinal axis represents that this puts corresponding light intensity.Because the center O of semicircular ring structure 16 ₂With measured laser device 1 luminescence center O ₁Inconsistent, so O ₁The light intensity of some test is not a largest light intensity, and the peak point of C3 curve can not be positioned on the coordinate system longitudinal axis yet, can obtain the distance L 3 of the position coordinates G1 of peak point and it and the longitudinal axis by data processing, L3 is the displacement that need adjust in X-direction, manually make four travelling carriages 5 mobile L3 distance on corresponding direction by vernier knob, finish X-direction to the heart.In like manner, the position deviation of the peak point of the curve of light distribution that obtains according to light probe 9 and the longitudinal axis finish Y direction (among Figure 11 with X, Z axle vertical direction) to the heart.Accurately to behind the heart, the peak point that light probe 9 and light probe 10 rotate to the curve of light distribution of any position measurement all should be positioned on the coordinate system longitudinal axis, shown in curve C among Figure 12 4.When promptly rotating to any position, semicircular structure 16 and 19 center O ₃, O ₂All over against the luminescence center O of measured laser device 1 ₁, the light intensity that is detected all is a largest light intensity, this could guarantee to try to achieve the accuracy of the unglazed separation of light.

That as mentioned above, finishes X and Y-axis is in the center of optical fiber receive module 8 to measured laser device 1 behind the heart in X, Y direction.Carry out Z axle the heart is regulated below.The relative position of laser and optical fiber receive module 8 has two kinds of possibilities before regulating: laser is in the outside at optical fiber receive module 8 centers, as shown in figure 13; Perhaps, laser is in the inboard at optical fiber receive module 8 centers, as shown in figure 14.Z-direction the heart is regulated finished in the mobile regulatory function of Z-direction with around the rotation regulatory function of Y-axis jointly by four-dimensional travelling carriage 5.At first, the current location after finishing X and Y-axis the heart is regulated when promptly laser is in position S3 among Figure 13, obtains O on the semicircular structure 19 ₂The light intensity Po2 that point detects then, starts the rotation regulatory function of four-dimensional travelling carriage 5, makes laser be rotated counterclockwise 90 ° of position S4 that reach among Figure 13, at this moment, obtains O on the semicircular structure 19 ₄The light intensity Po4 that point detects is if Po2 ≠ Po4 illustrates that laser 1 is not in the center of optical fiber receive module 8 this moment.Next start the mobile regulatory function of four-dimensional travelling carriage 5 in Z-direction, laser is moved a certain distance along Z axle positive direction after, repeat said process again, obtain O on the semicircular structure 19 this moment respectively ₂And O ₄Light intensity Po2 ' and Po4 ' that point detects, if have Po2 '＞Po2 and | Po2-Po4|＜| Po2 '-Po4 ' |, illustrate that then laser is the inboard that is in optical fiber receive module 8 centers, i.e. situation as shown in figure 14, so, the position of laser should be regulated to the negative direction of Z axle; Otherwise, if having Po2 '＜Po2 and | Po2-Po4|＞| Po2 '-Po4 ' |, illustrate that then laser is the outside that is in optical fiber receive module 8 centers, i.e. situation as shown in figure 13, so, the position of laser should be regulated to the positive direction of Z axle.After the adjusting direction of need determining, start four-dimensional travelling carriage 5 and carry out minor adjustments to the direction of appointment, and behind every adjusting certain distance, start the rotation regulatory function of four-dimensional travelling carriage 5, obtain O on the semicircular structure 19 respectively in the mobile regulatory function of Z-direction ₂And O ₄The light intensity that detects of point, and two light intensity values are compared constantly repeats said process, after the difference of 2 light intensity values is less than certain little numerical value, thinks that this moment, laser was in the center of optical fiber receive module 8 in Z-direction, as shown in figure 15.In sum, finish laser and optical fiber receive module 8 on Z-direction to the heart.

With centre wavelength 808nm, the quasi-continuous semiconductor laser of peak power 1200w is a tested object, and said apparatus is applied to it is carried out angle of divergence test experiments.Drive condition is as follows: drive current: 110A; Pulse frequency: 2Hz; Pulsewidth: 200 μ s, adopt high energy semiconductor laser divergence angle test system and test of the present invention.

Figure 16 shows light probe 9 and surveys the curve of light distribution that obtains, and has shown 6 among the figure, test interval 18 degree.Figure 17 shows light probe 10 and surveys the curve of light distribution that obtains, and has shown 3 among the figure, test interval 45 degree.Figure 18 shows light probe 9 and light probe 10 is surveyed two the hot spot outer rim curves of the sharp 1 smooth beam Propagation of the measured laser device that obtains to the different distance place, and the hot spot outer rim curve major axis that light probe 9 detects is 162mm, and minor axis is 42mm; It is 124mm that light probe 10 is surveyed the hot spot outer rim curve major axis that obtains, and minor axis is 31mm.The fast axle and the slow axis angle of divergence of trying to achieve this laser are respectively: 41.2 degree and 11.9 degree.

Claims (14)

1, a kind of high energy semiconductor laser divergence angle method of testing, it is characterized in that, geometric properties with direction of beam propagation different distance place two hot spot outer rims curve is tried to achieve laser divergence angle, hot spot outer rim curve is by two vertical mutually, placements with one heart, above evenly the rotation sweep of the light probe of distribution multifiber survey and obtain, another termination photo-detector of optical fiber comprises the steps:

(1) make measured laser device (1) center be in the center of optical fiber receive module (8) with perusal;

(2) start driving power (2) and cooling water recirculation system (4), make measured laser device (1) normally luminous;

(3) X-direction is to the heart: the curve of light distribution of surveying the X-direction that obtains measured laser device (1), try to achieve the position coordinates of peak of curve point and the distance (L3) between optical fiber receive module (8) central point, manual adjustments, make four-dimensional travelling carriage (5) at X-direction displacement (L3), finish horizontal direction the heart;

(4) Y direction is to the heart: the same step of principle (3), and direction is a Y-axis, other is identical;

(5) Z-direction is to the heart: (5 finish jointly in the mobile regulatory function of Z-direction with around the rotation regulatory function of Y-axis by four-dimensional travelling carriage;

(6) start stepping motor (11) and rotate from the fixed position, change 1.8 degree after, of short duration wait, data collecting module collected is to two groups of test datas, and passes to PC (14), PC (14) receives, preserves test data;

(7) repeat above-mentioned steps (5), finish 180 degree up to stepping motor (11) and rotate;

(8) PC (14) receives 200 groups of the test datas that obtain by optical fiber receive module, to every group of test data curve fit, obtains 200 of the corresponding curves of light distribution;

(9) try to achieve two hot spot marginal points according to every curve of light distribution, can obtain the hot spot marginal point of 400 diverse locations altogether;

(10), obtain two hot spot outer rim curves at beam Propagation different distance place to hot spot marginal point curve fit;

(10) try to achieve the major axis and the minor axis of two hot spot outer rim curves respectively;

(11) two major axis are depicted in the same coordinate system system, two minor axises are depicted in another coordinate system, try to achieve the fast axle and the slow axis angle of divergence of measured laser device (1).

2, energy semiconductor laser divergence angle method of testing according to claim 1 is characterized in that described measured laser device (1) is meant the high energy semiconductor laser that need carry out angle of divergence test.

3, high energy semiconductor laser divergence angle method of testing according to claim 1 is characterized in that, described optical fiber receive module (8) is the device that is used to receive and survey light.

4, high energy semiconductor laser divergence angle method of testing according to claim 1 is characterized in that, described driving power (2) is the driver that is used to drive measured laser device (1) operate as normal.

5, according to the described high energy semiconductor laser divergence angle method of testing of claim, it is characterized in that described cooling water recirculation system (4) the measured laser device (1) that is used to freeze.

6, high energy semiconductor laser divergence angle method of testing according to claim 1 is characterized in that, described four-dimensional travelling carriage (5) is gone up and loaded measured laser device (1), is used for measured laser device (1) and with optical fiber receive module (8) heart is regulated.

7, high energy semiconductor laser divergence angle method of testing according to claim 1, it is characterized in that, described stepping motor (11) can drive optical fiber receive module (8) and rotate, thus the light distribution of the measured laser device (1) of the whole beam plane of scanning probe.

8, high energy semiconductor laser divergence angle method of testing according to claim 1, it is characterized in that, the described curve of light distribution is meant that the luminous beam of measured laser device (1) is transferred to a distance, the optical fiber receive module of being placed at an angle (8) is surveyed the light intensity curve that obtains, and is the bell jar type in theory.

9, high energy semiconductor laser divergence angle method of testing according to claim 2, it is characterized in that, described hot spot edge is meant that laser beam is transferred to a certain distance, the set of the unglazed separation of all light on the whole circumference, light intensity value is the 1/e of largest light intensity on the curve of light distribution of all angles that promptly a certain distance receives ²The time location point set.

10, high energy semiconductor laser divergence angle method of testing according to claim 1 is characterized in that, described data acquisition module (13) is used for the reception of analog signal and converts digital signal to, can adopt the universal data collection card to realize.

11, high energy semiconductor laser divergence angle method of testing according to claim 1, it is characterized in that, described data processing and demonstration are meant in computer and realize that by VB, VC software programming Presentation Function comprises: the tabulation demonstration of every group of test data, the demonstration of every light intensity curve, the demonstration of two hot spot outer rim curves, the demonstration of angle of divergence result of calculation.

12, a kind of device of realizing each described high energy semiconductor laser divergence angle method of testing of claim 1～11, it is characterized in that, comprise: driving power (2), cooling water platform (3), cooling water recirculation system (4), four-dimensional travelling carriage (5), group of motors (6), driver (7), optical fiber receive module (8), stepping motor (12), driver (13), data acquisition module (14) and PC (15), measured laser device (1) is placed on the water-cooled platform (3), water-cooled platform (3) is placed on the four-dimensional travelling carriage (5), water-cooled platform (3) is connected with hydrologic cycle cooling system (4) by water pipe, four-dimensional travelling carriage (5) and group of motors (6) mechanical connection, group of motors (6) is electrically connected with driver (7), driving power (5) is electrically connected with measured laser device (1), optical fiber receive module (8) is made up of light probe (9) and light probe (10), light probe (9) and light probe (10) are concentric, the vertical placement is by connector (11) mechanical connection; Light probe (9) is connected with stepping motor (12) solid mechanical, (12 are electrically connected with driver (13) stepping motor, optical fiber receive module (8), data acquisition module (14), computer (15) are electrically connected successively, and driver (7), driver (13) are electrically connected with computer (15) respectively.

13; a kind of device of realizing each described high energy semiconductor laser divergence angle method of testing of claim 1～11 according to claim 12; it is characterized in that; described light probe (9) is by semicircular ring structure (16); optical fiber (17); photodiode (18) is formed; semicircular ring structure (16) is connected with optical fiber (17); optical fiber (17) angle intervals＜5; optical fiber (17) is connected with photodiode (18) by standard fiber FC interface; semicircular ring structure (16) is heat-resisting resistant to elevated temperatures organic resin material; optical fiber (17) is single mode or multimode fiber, and light probe (10) comprising: semicircular ring structure (19); optical fiber (20); photodiode (21).

14, according to claim 12 or 13 described a kind of devices of realizing each described high energy semiconductor laser divergence angle method of testing of claim 1～11, it is characterized in that, described light probe (10) and the difference of light probe (9) are that the radius of the semicircular ring structure (16) of two probes and semicircular ring structure (19) is different, and other compositions are all identical.

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