CN104237123B - The synchronizing detection device and method in laser-induced cavity radius and cycle on solid-surface - Google Patents

Abstract

The invention belongs to photodetection field, it discloses a kind of method that the bulla radius of laser-induced cavity on solid-surface and pulsation period can be carried out synchronizing detection efficiently.The method, according to light beam deflection principle, uses the light spot shape formed by LASER Light Source and optical element combination for the more uniform light beam of " wordline " and light distribution as detection light, laser on solid-surface being lured into, the cavity of generation detects.Detection optical signal is converted into the signal of telecommunication by photomultiplier tube, and is illustrated by oscillograph.The data obtaining oscillograph are analyzed, and can obtain radius and the pulsation period information of cavity simultaneously.The method achieve by the single measurement extraction to same cavity radius Yu pulsation period information, the most efficiently, and be equally applicable to the bulla radius cavity less than 1mm on solid-surface is measured.

Description

The synchronizing detection device and method in laser-induced cavity radius and cycle on solid-surface

Technical field

The invention belongs to cavity maximum bubble radius and the detection device of pulsation period on photodetection field, particularly solid-surface And detection method.

Background technology

It is owing to it has attracted many for the destruction of solid-surface, this characteristic that cavitation phenomena starts concerned Scholar expands a series of research to it, and is successfully applied to many fields, including cavity surface clean, sky The interaction of bubble biological tissue, Laser Underwater propelling etc..Bulla radius and the pulsation period of cavity are as cavity Fundamental quantity, the former can characterize the energy of cavity and the degree that crumbles and fall, and the latter can reflect the Evolution Characteristics of cavity, thus Near solid-surface, in the research field of cavity, bulla radius and pulsation period to cavity carries out detection and seems the heaviest Want.After nineteen sixty laser instrument comes out, due to the cavity that it can produce repeatable height, controllability is good, Sphere symmetry is good And one of cavity producing method being increasingly becoming main flow, and it is widely used in the research of cavity, thus promote near solid-surface The Detection Techniques of the research of cavity, especially cavity bulla radius and pulsation period have obtained significant progress.

On solid-surface in the research field of laser-induced cavity, old laugh at et al. proposed in 2004 a kind of inclined based on light beam Robin can be to the laser-induced cavity method that bulla radius and pulsation period detect on solid-surface.The method utilizes to be visited Light-metering is changing thus the characteristic that deflects due to medium refraction index through cavity, by carrying out cavity center Single detects, and i.e. can get the cycle information of cavity.And when measuring cavity bulla radius, the method needs cavity Diverse location detect, analyze deflection light waveform in cavity life cycle, with characteristic signal contrast, obtain sky The radius information of bubble；On this basis, then through measurement being repeated several times, to the deflection light that recorded on certain detecting location Waveform occurs the maximum radius estimated value as cavity when the characteristic signal probability of maximum radius is 50%.The method is main Having three drawbacks, one is to need to do substantial amounts of repeated measure at each point of measuring, and this is the highest to the repeatable requirement of cavity, The analysis workload in later stage is huge simultaneously；Two be the cavity obtained bulla radius be estimated value based on probability, still may be used Bigger error can be there is；Three be when the cavity detected bulla radius less than 1mm time, due to needs repetitive measurement with And the unstability of laser energy, measure the result precision obtained limited.

Summary of the invention

It is an object of the invention to provide the same of laser-induced cavity bulla radius and pulsation period on a kind of efficient solid-surface Step detection device and detection method thereof.

The technical solution realizing the object of the invention is: on a kind of solid-surface, the synchronization in laser-induced cavity radius and cycle is visited Survey device, including detection light beam laser, laser beam can be expanded n times meniscus group, the first adjustable optical narrow Seam, the second adjustable optical slit, first there is the cylindrical mirror of converging action, the second cylindrical mirror with converging action, poly- Focus lens, interference filter element, multidimensional optical fiber locator, light deflection detection system multidimensional translation stage, optical fiber, photoelectricity times Increase pipe, oscillograph, possess the container of energy transmission detection light window, the object containing solid-surface；

Wherein detect light beam laser, meniscus group, the first adjustable optical slit, the second adjustable optical slit, first There is the cylindrical mirror of converging action, second there is the cylindrical mirror of converging action, condenser lens, interference filter element, multidimensional light Fine localizer is sequentially coaxially arranged on light deflection detection system multidimensional translation stage on detection beam emissions direction, possesses The container of energy transmission detection light window is positioned at the first cylindrical mirror with converging action and second and has the cylinder of converging action Between mirror；Object containing solid-surface is fixed in the container possessing energy transmission detection light window, and one end of optical fiber is fixed on many On the optical fiber locator of position, the other end is connected with oscillograph as the input of photomultiplier tube, the outfan of photomultiplier tube； The gap median perpendicular of the first adjustable optical slit in the solid-surface containing solid-surface object, and with the second adjustable optical slit The transmitting direction of gap center line and detection light beam laser is the most vertical.

Laser-induced cavity radius and the detection of the synchronizing detection device in cycle on a kind of solid-surface based on above-mentioned detection device Method, comprises the following steps:

Step 1, utilization detect light beam laser and laser beam can expand the meniscus group of n times, produce hot spot straight The footpath detection light beam more than 2 times of the maximum cavity radius produced on object solid-surface；Wherein n is the positive integer more than 1；

Step 2, guarantee the object containing solid-surface do not shelter from detection light beam in the case of, regulate each device and make detection Light beam laser, meniscus group, the first adjustable optical slit, the second adjustable optical slit, first there is converging action Cylindrical mirror, second there is the cylindrical mirror of converging action, condenser lens, interference filter element and to be fixed on multidimensional optical fiber fixed Fiber port on the device of position is the most contour, and ensures that the first adjustable optical slit, the second adjustable optical slit do not shelter from Detection light beam；

Step 3, on the premise of guaranteeing optical diffraction not to occur, reduce the gap width of the first adjustable optical slit, Make the light beam by this adjustable optical slit the thinnest；

Step 4, before the gap width of the second adjustable optical slit is not less than the maximum cavity radius produced on solid-surface Put the gap width reducing this optical slot, until producing light distribution uniform " wordline " detection light beam, now The gap width of the second adjustable optical slit is s；

Step 5, regulation multidigit optical fiber locator so that the signal voltage obtained on oscillograph is maximum, is designated as V_max；

Step 6, sheltering from detection light beam completely, the signal voltage now obtained on oscillograph is V_min；

Step 7, regulation light deflection detection system multidimensional translation stage so that detection light beam obtains through focus of cylindrical mirror " line " place straight line is through the center of cavity, and is perpendicular to the solid-surface containing solid-surface object；

Step 8, regulation light deflection detection system multidimensional translation stage, make detection light beam to the solid-surface containing solid-surface object Mobile, observe the change of oscillographic waveform simultaneously, when the signal voltage on oscillograph begins to decline, be detection light beam The critical state contacted with the solid-surface containing solid-surface object, fixing light deflection detection system multidimensional translation stage；

Step 9, utilize superlaser to produce cavity on the solid-surface containing solid-surface object, record in oscillograph and show Light deflection waveform V (t), radius change curve R (t) of this cavity is represented by:

$R\left(t\right)=s(1-\frac{V\left(t\right)}{V_{\max }-V_{\min }})$

Thus, bulla radius and the pulsation period of this cavity i.e. can be obtained by R (t).

Compared with prior art, its remarkable advantage is the present invention: 1) assembly of the invention can to same cavity Bulla radius and pulsation period detect simultaneously；2) when the method utilizing the present invention detects, it is only necessary to single is surveyed Amount i.e. can get bulla radius and the pulsation period information of cavity, greatly reduces workload；3) assembly of the invention It is applicable to bulla radius bulla radius and pulsation period of cavity less than 1mm on solid-surface is detected.

Below in conjunction with the accompanying drawings the present invention is described in further detail.

Accompanying drawing explanation

Fig. 1 is can synchronizing bulla radius and the pulsation period of laser-induced cavity on solid-surface of using of the present invention The light deflection detection system schematic diagram of detection, wherein illustration (a) and illustration (c) are respectively the detection of position shown in its corresponding arrow Beam cross section figure, illustration (b) is the right view (sight line edge-x-axis direction) of solid box interior-deficiency coiler part, and illustration (d) is real The right view (sight line edge-x-axis direction) of part shown in wire frame chain lines frame.

Fig. 2 is to detect the oscillogram of laser-induced cavity on solid-surface by what oscillograph obtained in example, and wherein dotted line frame is lived Part be induced with laser cavity produce during, caused by the shock wave given off when laser optics punctures.

Fig. 3 is the radius time history plot of cavity in example, and the part that wherein dotted line frame is lived is that induced with laser is empty During bubble produces, caused by the shock wave given off when laser optics punctures, cavity radius changes over and arises from an A The moment at place.

Fig. 4 is " wordline " detection light beam equalization of intensity test figure in example.

In figure, reference and corresponding part thereof are: 1 is detection light beam laser；2 for can expand n times by laser beam Meniscus group；3 is the first adjustable optical slit；4 is the second adjustable optical slit；5 is first to have converging action Cylindrical mirror；6 is the second cylindrical mirror with converging action；7 is condenser lens；8 is interference filter element；9 is multidimensional Optical fiber locator；10 deflect detection system multidimensional translation stage for light；11 is optical fiber；12 is photomultiplier tube；13 are Oscillograph；14 for possessing the container of energy transmission detection light window；15 is the object containing solid-surface；16 is to swash on solid-surface The shape of photic cavity and position view.

Detailed description of the invention

In conjunction with Fig. 1, laser-induced cavity radius and the synchronizing detection device in cycle on a kind of solid-surface of the present invention, including visiting Meniscus group the 2, the first adjustable optical slit 3, second that survey light beam laser 1, laser beam can expand n times can Adjust optical slot 4, first there is the cylindrical mirror 5 of converging action, second there is the cylindrical mirror 6 of converging action, condenser lens 7, interference filter element 8, multidimensional optical fiber locator 9, light deflection detection system multidimensional translation stage 10, optical fiber 11, light Electricity multiplier tube 12, oscillograph 13, possessing can the container 14 of transmission detection light window, object 15 containing solid-surface；

Wherein detection light beam laser 1, meniscus group the 2, first adjustable optical slit the 3, second adjustable optical slit 4, First there is the cylindrical mirror 5 of converging action, second there is the cylindrical mirror 6 of converging action, condenser lens 7, interference filter element 8, multidimensional optical fiber locator 9 detection beam emissions direction on be sequentially coaxially arranged on light deflection detection system multidimensional put down In moving stage 10, possesses the container 14 of energy transmission detection light window between cylindrical mirror 5 and cylindrical mirror 6；Containing solid-surface Object 15 be fixed in container 14, one end of optical fiber 11 is fixed on multidigit optical fiber locator 9, other end conduct The input of photomultiplier tube 12, the outfan of photomultiplier tube 12 is connected with oscillograph 13；Adjustable optical slit 3 Gap median perpendicular in the solid-surface of object 15, and swash with gap center line and the detection light beam of adjustable optical slit 4 The transmitting direction of light device 1 is the most vertical.

The transmitting of described detection light beam laser 1 is oriented parallel to the solid-surface of object 15.

Described detection light beam laser 1 optimal wavelength is 632.8nm, and spot diameter is the He-Ne laser instrument of 2mm.

Laser-induced cavity radius and the synchronizing detection method in cycle on a kind of solid-surface based on above-mentioned detection device, including with Lower step:

Step 1, utilization detect light beam laser 1 and laser beam can expand the meniscus group 2 of n times, produce light The spot diameter detection light beam more than 2 times of the maximum cavity radius produced on the solid-surface of object 15；Wherein n is more than 1 Positive integer；

Step 2, the object 15 guaranteed containing solid-surface do not shelter from detection light beam in the case of, regulate each device and make spy Survey light beam laser 1, meniscus group the 2, first adjustable optical slit the 3, second adjustable optical slit 4, first have The cylindrical mirror 5 of converging action, second there is the cylindrical mirror 6 of converging action, condenser lens 7, interference filter element 8 and solid The port of the optical fiber 11 on multidimensional optical fiber locator 9 is the most contour, and ensures the first adjustable optical slit 3, second Adjustable optical slit 4 does not shelter from detection light beam；

Step 3, on the premise of guaranteeing optical diffraction not to occur, reduce the gap width of the first adjustable optical slit 3, Make the light beam by this adjustable optical slit the thinnest；

Step 4, in the gap width of the second adjustable optical slit 4 not less than the maximum cavity radius produced on solid-surface The gap width of this optical slot is reduced under premise, until producing light distribution uniform " wordline " detection light beam, this Time the second adjustable optical slit 4 gap width be s；

Step 5, regulation multidigit optical fiber locator 9 so that the signal voltage obtained on oscillograph 13 is maximum, is designated as V_max；

Step 6, sheltering from detection light beam completely, the signal voltage now obtained on oscillograph 13 is V_min；

Step 7, regulation light deflection detection system multidimensional translation stage 10 so that detection light beam focuses on through cylindrical mirror 5 " line " place straight line arrived is through the center of cavity, and is perpendicular to the solid-surface of object 15；

Step 8, regulation light deflection detection system multidimensional translation stage 10, make detection light beam move to the solid-surface of object 15 Dynamic, the waveform change of observation oscillograph 13, when the signal voltage on oscillograph 13 begins to decline, is detection simultaneously The critical state that light beam contacts with the solid-surface of object 15, fixing light deflection detection system multidimensional translation stage 10；

Step 9, utilize superlaser to produce cavity on the solid-surface of object 15, record display in oscillograph 13 Light deflection waveform V (t), radius change curve R (t) of this cavity is represented by:

$R\left(t\right)=s(1-\frac{V\left(t\right)}{V_{\max }-V_{\min }})$

Thus, bulla radius and the pulsation period of this cavity i.e. can be obtained by R (t).

Preferably, detecting light beam laser 1 described in step 1 is 632.8nm for wavelength, and spot diameter is 2mm's He-Ne laser instrument.

Below in conjunction with embodiment the present invention done further detailed description:

Embodiment:

A kind of based on cavity radius on the solid-surface of the synchronizing detection device in laser-induced cavity radius and cycle on solid-surface and The detection method in cycle, specifically includes following steps:

Step 1, according to light deflection detection system structural representation build light deflection detection system.Wherein detection light beam is adopted With He-Ne laser beam (wavelength 632.8nm, spot diameter is 2mm)；Meniscus group 2 uses 6 power beam expansion lens； The material of container 14 is to be the optical glass that near 632.8nm and 1064nm, absorbance is higher at wavelength, and inside is filled Deionized water；Object 15 is the titanium matter target (high 6mm, disc radius is 2mm) of cylindrical shape, and solid-surface is One of them disc；Cavity is focused on by Nd:YAG laser beam (wavelength 1064nm, pulsewidth 7ns) and produces on solid-surface Raw.

Step 2, guarantee titanium target 15 do not shelter from detection light beam in the case of, regulate each device and make He-Ne laser Device 1, beam expanding lens the 2, first adjustable optical slit the 3, second adjustable optical slit 4, the first cylinder with converging action Mirror 5, second there is the cylindrical mirror 6 of converging action, condenser lens 7, interference filter element 8 and to be fixed on multidimensional optical fiber fixed The port of the optical fiber 11 on the device 9 of position is the most contour, and ensures first adjustable optical slit the 3, second adjustable optical slit 4 Do not shelter from detection light beam.

Step 3, on the premise of guaranteeing optical diffraction not to occur, reduce the gap width of the first adjustable optical slit 3, Making the light beam by this adjustable optical slit the thinnest, in this example, the gap width minimum of adjustable optical slit 3 is adjustable to 0.28mm。

Step 4, due in this example detected object cavity bulla radius be typically not more than 4mm, therefore we are by the The gap width of two adjustable optical slits 4 is contracted to 4mm, is designated as s=4mm.

Step 5, regulation multidigit optical fiber locator 9 so that the signal voltage obtained on oscillograph 13 is maximum, is designated as V_max, By computer disposal oscilloscope signal, readable V_max=328.6mV.

Step 6, sheltering from detection light beam completely, the signal voltage now obtained on oscillograph 13 is designated as V_min, by meter Calculation machine processes oscilloscope signal, readable V_min=3.98mV.

Step 7, regulation light deflection detection system multidimensional translation stage 10 so that detection light beam focuses on through cylindrical mirror 5 " line " place straight line arrived is through the center of cavity, and is perpendicular to the solid-surface of titanium target 15.

Step 8, regulation light deflection detection system multidimensional translation stage 10, make detection light beam move to the solid-surface of titanium target 15 Dynamic, the waveform change of observation oscillograph 13, when the signal voltage on oscillograph 13 begins to decline, is detection simultaneously The critical state that light beam contacts with the solid-surface of titanium target 15, fixing light deflection detection system multidimensional translation stage 10.

Step 9, utilize Nd:YAG laser beam focus on the solid-surface of titanium target 15 generation cavity, record oscillography Light deflection waveform V (t) of display in device 13, as shown in Figure 2；Pass through below equation:

$\begin{array}{c}R\left(t\right)=s(1-\frac{V\left(t\right)}{V_{\max }-V_{\min }})\\ =4(1-\frac{V\left(t\right)}{324.62})\end{array}$

I.e. can obtain this cavity radius versus time curve, as shown in Figure 3.By computer, it is processed, can Obtain the R of bulla radius of this cavity further_max1=0.57mm, for the first time pulsation period T_os1=82.2 μ s, for the second time arteries and veins Dynamic cycle T_os2=48.9 μ s, for the third time pulsation period T_os3=38.3 μ s.

Laser-induced cavity radius and the topmost premise of detection method while the cycle on solid-surface provided by the present invention It is to produce light distribution uniform " wordline " detection light beam.Can produce to be verified the detection device of the present invention Light distribution uniform " wordline " detects light beam, and the detection light beam in example is detected by we, and way is as follows:

After step 8, regulation light deflection detection system multidimensional translation stage 10, by the detection light beam Gu Bi to titanium target 15 0.1mm is moved in face.Now, the detection light beam of 4mm length has the part of a length of 0.1mm to be sheltered from by titanium target, shows Signal voltage value shown by ripple device, corresponding to detection light beam wide for 3.9mm, is recorded by computer analysis and is now shown The registration of ripple device.Again detection light beam is moved 0.1mm to the solid-surface of titanium target 15, record by computer analysis The most oscillographic registration.Circulate this step, until detection light beam is blocked by titanium target completely.Detection light beam is not blocked The length of part is designated as X, i.e. can obtain detecting light beam and not be blocked the signal voltage that partial-length X receives with oscillograph Graph of a relation, as shown in Figure 4.

The signal voltage Voltage that partial-length X and oscillograph receive it will be seen that detection light beam is not blocked is almost Presenting linear relation, this shows that the light distribution of " wordline " detection light beam used in this example is more uniform, enters One step shows that the method that laser-induced cavity radius on solid-surface and cycle carry out synchronizing detection of the present invention is feasible.

Claims (5)

1. laser-induced cavity radius and the synchronizing detection device in cycle on a solid-surface, it is characterized in that, including detection light beam laser (1), laser beam can be expanded the meniscus group (2) of n times, first adjustable optical slit (3), second adjustable optical slit (4), first cylindrical mirror (5) with converging action, second cylindrical mirror (6) with converging action, condenser lens (7), interference filter element (8), multidimensional optical fiber locator (9), light deflection detection system is with multidimensional translation stage (10), optical fiber (11), photomultiplier tube (12), oscillograph (13), possesses the container (14) of energy transmission detection light window, object (15) containing solid-surface；

nullWherein detect light beam laser (1)、Meniscus group (2)、First adjustable optical slit (3)、Second adjustable optical slit (4)、First cylindrical mirror (5) with converging action、Second cylindrical mirror (6) with converging action、Condenser lens (7)、Interference filter element (8)、Multidimensional optical fiber locator (9) is sequentially coaxially arranged on light deflection detection system multidimensional translation stage (10) on detection beam emissions direction，The container (14) possessing energy transmission detection light window is positioned between the cylindrical mirror (6) that the first cylindrical mirror (5) and second with converging action has converging action，Object (15) containing solid-surface is fixed in container (14)，One end of optical fiber (11) is fixed on multidimensional optical fiber locator (9)，The other end is as the input of photomultiplier tube (12)，The outfan of photomultiplier tube (12) is connected with oscillograph (13)；The gap median perpendicular of the first adjustable optical slit (3) is in the solid-surface of object (15) and the most vertical with the transmitting direction of the gap center line of the second adjustable optical slit (4) and detection light beam laser (1).

The synchronizing detection device in laser-induced cavity radius and cycle on solid-surface the most according to claim 1, it is characterised in that the transmitting of detection light beam laser (1) is oriented parallel to the solid-surface of object (15).

The synchronizing detection device in laser-induced cavity radius and cycle on solid-surface the most according to claim 1, it is characterised in that described detection light beam laser (1) be wavelength be 632.8nm, spot diameter is the He-Ne laser instrument of 2mm.

4. one kind based on the detection method of the synchronizing detection device in laser-induced cavity radius and cycle on solid-surface described in claim 1, it is characterised in that comprise the following steps:

Step 1, utilization detect light beam laser (1) and laser beam can expand the meniscus group (2) of n times, produce the spot diameter detection light beam more than 2 times of the maximum cavity radius produced on the solid-surface of object (15)；Wherein n is the positive integer more than 1；

Step 2, in the case of guaranteeing that the object containing solid-surface (15) does not shelter from detection light beam, regulate each device and make detection light beam laser (1), meniscus group (2), first adjustable optical slit (3), second adjustable optical slit (4), first cylindrical mirror (5) with converging action, second cylindrical mirror (6) with converging action, condenser lens (7), interference filter element (8) and the port of optical fiber (11) being fixed on multidimensional optical fiber locator (9) are the most contour, and ensure the first adjustable optical slit (3), second adjustable optical slit (4) does not shelter from detection light beam；

Step 3, on the premise of guaranteeing optical diffraction not to occur, reduce the gap width of the first adjustable optical slit (3), make the light beam by this adjustable optical slit the thinnest；

Step 4, on the premise of the gap width of the second adjustable optical slit (4) is not less than the maximum cavity radius produced on solid-surface, reduce the gap width of this optical slot, until producing light distribution uniform " wordline " detection light beam, now the gap width of the second adjustable optical slit (4) is s；

Step 5, regulation multidimensional optical fiber locator (9) so that the signal voltage obtained on oscillograph (13) is maximum, is designated as V_max；

Step 6, sheltering from detection light beam completely, the signal voltage now obtained on oscillograph (13) is V_min；

Step 7, regulation light deflection detection system are with multidimensional translation stage (10), make to detect light beam and focus on " line " place straight line of obtaining through the center of cavity through cylindrical mirror (5), and be perpendicular to the solid-surface of object (15)；

Step 8, regulation light deflection detection system are with multidimensional translation stage (10), detection light beam is made to move to the solid-surface of object (15), observe the waveform change of oscillograph (13) simultaneously, when the signal voltage on oscillograph (13) begins to decline, it is the detection critical state that contact with the solid-surface of object (15) of light beam, fixes light and deflect detection system with multidimensional translation stage (10)；

Step 9, superlaser is utilized to produce cavity on the solid-surface of object (15), recording light deflection waveform V (t) of display in oscillograph (13), radius change curve R (t) of this cavity is represented by:

Thus, bulla radius and the pulsation period of this cavity i.e. can be obtained by R (t).

Detection method the most according to claim 4, it is characterised in that described in step 1 detect light beam laser (1) be wavelength be 632.8nm, spot diameter is the He-Ne laser instrument of 2mm.