CN215375237U - Nondestructive testing system for improving laser ultrasonic signal based on beam shaping - Google Patents
Nondestructive testing system for improving laser ultrasonic signal based on beam shaping Download PDFInfo
- Publication number
- CN215375237U CN215375237U CN202121734279.8U CN202121734279U CN215375237U CN 215375237 U CN215375237 U CN 215375237U CN 202121734279 U CN202121734279 U CN 202121734279U CN 215375237 U CN215375237 U CN 215375237U
- Authority
- CN
- China
- Prior art keywords
- laser
- lens
- beam shaping
- ultrasonic signal
- nondestructive testing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000007493 shaping process Methods 0.000 title claims abstract description 17
- 238000009659 non-destructive testing Methods 0.000 title claims abstract description 13
- 230000003287 optical effect Effects 0.000 claims abstract description 17
- 230000001066 destructive effect Effects 0.000 claims description 5
- 230000002708 enhancing effect Effects 0.000 claims description 4
- 238000007689 inspection Methods 0.000 claims description 4
- 238000002604 ultrasonography Methods 0.000 claims description 4
- 238000005070 sampling Methods 0.000 claims description 3
- 230000005284 excitation Effects 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 6
- 230000007547 defect Effects 0.000 abstract description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 11
- 238000005516 engineering process Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 239000007822 coupling agent Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Landscapes
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The utility model relates to a nondestructive testing system for improving laser ultrasonic signals based on beam shaping, which comprises: the laser interferometer, a data processor electrically connected with the laser interferometer, and a laser, a beam expanding lens, a plano-convex conical lens, an optical lens group, a focusing lens, a total reflection lens and a vibrating lens which are sequentially arranged along a light path propagation path. The beneficial effects are that: laser beams emitted by the laser device are expanded to form light spots by the beam expander, then pass through the plano-convex cone lens and then pass through the optical lens group to control the beam waist distance of the light beams, so that the light beams are shaped, finally pass through the focusing lens, the total reflection lens and the vibrating lens in sequence to improve the power density and the ultrasonic intensity, finally the obtained annular light spots irradiate on the surface of a workpiece, the surface of the workpiece is subjected to a thermoelastic effect, the intensity of an excitation ultrasonic signal is enhanced, and the defect signal identification of a receiving end is facilitated.
Description
Technical Field
The utility model relates to the field of laser ultrasound, in particular to a nondestructive testing system for improving laser ultrasonic signals based on beam shaping.
Background
The traditional ultrasonic detection technology comprises a plurality of methods such as piezoelectric ultrasonic excitation, electromagnetic ultrasonic excitation, air coupling ultrasonic excitation and the like, and the traditional methods usually need to coat a coupling agent between a probe and a workpiece, so that the interference on ultrasonic signals is generated, and the surface of the workpiece is polluted. Due to the limitation of the excitation mode, the workpiece with a complex shape is difficult to effectively detect. Compared with the traditional ultrasonic detection technology, the laser ultrasonic detection technology has the advantages of non-contact, long distance, no need of a coupling agent, high bandwidth, high resolution and the like.
Because the laser ultrasonic detection technology is a nondestructive detection technology, a thermoelastic effect is formed on the surface of a workpiece, and because the signal intensity generated by laser ultrasonic is influenced by the laser power density and is between nondestructive and destructive, the weak receiving effect of the ultrasonic signal excited by laser is poor, and the detection is not facilitated.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a nondestructive testing system for improving laser ultrasonic signals based on beam shaping, so as to overcome the defects in the prior art.
The technical scheme for solving the technical problems is as follows: a non-destructive inspection system for enhancing laser ultrasonic signal based on beam shaping, comprising:
the laser interferometer, a data processor electrically connected with the laser interferometer, and a laser, a beam expanding lens, a plano-convex conical lens, an optical lens group, a focusing lens, a total reflection lens and a vibrating lens which are sequentially arranged along a light path propagation path.
On the basis of the technical scheme, the utility model can be further improved as follows.
Furthermore, the size of a light spot formed by a laser beam emitted by the laser after passing through the beam expander is 8-12 mm.
Further, the light spot shaped by the plano-convex cone lens is a circular ring with the roundness larger than 92%.
Furthermore, the adjustable multiplying power of the beam expander is 1-10 times.
Further, the energy density of the single pulse emitted by the laser is more than 200uJ/cm2The laser frequency is 1 kHz-100 kHz.
Further, the return signal strength of the laser interferometer is greater than 60%.
Further, the data processor comprises a gain amplifier, a data acquisition card and a PC end, and the laser interferometer, the gain amplifier, the data acquisition card and the PC end are electrically connected in sequence.
Further, the adjustment value of the gain amplifier is 10dB to 60 dB.
Furthermore, the sampling rate of the data acquisition card is more than or equal to 50 MS/s.
The utility model has the beneficial effects that:
laser beams emitted by a laser device are expanded to form light spots by a beam expander, then pass through a plano-convex cone lens and then pass through an optical lens group to control the beam waist distance of the light beams, so that the light beams are shaped, finally pass through a focusing lens, a total reflection lens and a vibrating lens in sequence to improve the power density and the ultrasonic intensity, finally the obtained annular light spots are irradiated on the surface of a workpiece, the surface of the workpiece is subjected to a thermoelastic effect, the intensity of an excitation ultrasonic signal is enhanced, and the defect signal identification of a receiving end is facilitated;
in the traditional technology, under a high-temperature environment, due to the influence of high temperature, the ultrasonic signal which is not strong per se is further reduced, but the utility model does not limit environmental factors and greatly improves the excitation strength under the lossless condition;
when the thickness or the surface defect is tiny during detection, the defect signal is annihilated in noise, the signal improvement of longitudinal wave and transverse wave is large, and the detection precision improvement is facilitated.
Drawings
FIG. 1 is a block diagram of a non-destructive inspection system for enhancing laser ultrasonic signals based on beam shaping according to the present invention;
FIG. 2 is a graph comparing waveforms of different light sources;
fig. 3 is an annular spot diagram.
In the drawings, the components represented by the respective reference numerals are listed below:
1. the device comprises a laser interferometer, a laser 2, a laser 3, a beam expander, a plano-convex cone lens 4, a 5, an optical lens group 6, a focusing lens 7, a total reflection lens 8, a vibrating mirror 9, a gain amplifier 10, a data acquisition card 11, a PC terminal 12 and a workpiece.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the utility model.
Example 1
As shown in fig. 1, a non-destructive inspection system for enhancing laser ultrasonic signal based on beam shaping comprises:
the device comprises a laser interferometer 1, a data processor, a laser 2, a beam expander 3, a plano-convex conical lens 4, an optical lens group 5, a focusing lens 6, a total reflection lens 7 and a vibrating lens 8;
the signal output end of the laser interferometer 1 is electrically connected with the signal input end of the data processor, and the laser 2, the beam expanding lens 3, the plano-convex conical lens 4, the optical lens group 5, the focusing lens 6, the total reflection lens 7 and the vibrating lens 8 are sequentially arranged in a light path propagation path;
the plano-convex cone lens 4 is used for generating an annular light beam, the diameter of the generated annular light beam can be increased along with the distance, but the thickness of the annular light beam is kept unchanged;
the number of the optical lens group 5 is a plurality, and the optical lens group is similar to an objective lens and is used for magnifying a target for the first time;
the focusing lens 6 has the function of focusing light spots, so that the power density is higher, and the ultrasonic intensity can be improved;
the galvanometer 8 is of the existing structure, and can present scanning by driving an inner lens to rotate through a motor;
the laser interferometer 1 receives an ultrasonic signal by an optical interference method;
laser beams emitted by the laser 2 sequentially pass through the beam expander 3, the plano-convex conical lens 4, the optical lens group 5, the focusing lens 6, the total reflection lens 7 and the vibrating lens 8 and then are irradiated onto the workpiece 12, so that the workpiece 12 generates a thermo-elastic effect to generate ultrasonic signals on the surface of the workpiece 12, the laser interferometer 1 is started to capture the ultrasonic signals and transmit the ultrasonic signals to the data processor for analysis and calculation, and detection is completed.
Example 2
As shown in fig. 1, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the size of a light spot formed by a laser beam emitted by the laser 2 after passing through the beam expander 3 is 8-12 mm.
Example 3
As shown in fig. 3, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the light spot shaped by the plano-convex cone lens 4 is a circular ring with the roundness larger than 92%, and the power density consistency of each position of the formed circular light spot needs to be measured under an optical CCD camera.
Example 4
As shown in fig. 1, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the adjustable multiplying power of the beam expanding lens 3 is 1-10 times.
Example 5
As shown in fig. 1, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the energy density of a single pulse of laser emitted by the laser 2 is more than 200uJ/cm2The laser frequency is 1 kHz-100 kHz.
Example 6
As shown in fig. 1, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the return signal strength of the laser interferometer 1 is greater than 60%.
Example 7
As shown in fig. 1, this embodiment is further optimized based on embodiment 1, and it specifically includes the following steps:
the data processor comprises a gain amplifier 9, a data acquisition card 10 and a PC (personal computer) terminal 11, wherein the signal output end of the laser interferometer 1 is electrically connected with the signal input end of the gain amplifier 9, the signal output end of the gain amplifier 9 is electrically connected with the signal input end of the data acquisition card 10, the signal output end of the data acquisition card 10 is electrically connected with the signal input end of the PC terminal 11, and the laser interferometer 1 sends the captured signals to the gain amplifier 9 for amplification processing and then transmits the signals to the PC terminal 11 through the data acquisition card 10 for analysis and calculation.
Example 8
As shown in fig. 1, this embodiment is further optimized based on embodiment 7, and it specifically includes the following steps:
the adjustment value of the gain amplifier 9 is 10dB to 60 dB.
Example 9
As shown in fig. 1, this embodiment is further optimized based on embodiment 8, and it specifically includes the following steps:
the sampling rate of the data acquisition card 10 is greater than or equal to 50 MS/s.
In order to demonstrate the technical effect, the external factors such as parameters, workpieces and the like are kept unchanged, the wave distribution excited by the point light source is compared with the wave distribution excited by the point light source, as shown in fig. 2, in the wave distribution of the light beam obtained after the light beam is shaped, transverse waves and longitudinal waves close to the central part of the light source are superposed, and the point light source is different from the point light source and has no symmetry.
The specific implementation method comprises the following steps:
firstly, wiping a laser outlet of a laser 2 by alcohol, and protecting lenses by a beam expander 3, a plano-convex conical lens 4, an optical lens group 5, a focusing lens 6, a total reflection lens 7 and a vibrating lens 8 to ensure that the surface of an optical device is free from dirt and the power of a laser beam is influenced;
secondly, checking the light path of the laser 2 to enable the laser beam to enter from the center of a light inlet of the beam expander 3 and the emitted laser center to exit through the plano-convex cone lens 4, the optical lens group 5, the focusing lens 6 and the total reflection lens 7, wherein in the process, the light beam needs to pass through the center of each optical device, the light beam needs to be kept parallel or vertical, and the laser beam is always consistent with the center of each lens in the detection process and does not change along with the movement of the test;
thirdly, adjusting the scanning area of the galvanometer 8, and starting the laser interferometer 1 to adjust the focal length to enable the intensity of a return signal to reach 60%;
fourthly, adjusting a gain amplifier 9 to amplify the effective ultrasonic signals and filtering out clutter signals generated by the interference of the electric signals and noise signals influenced by the environment;
fifthly, determining a detection position, setting parameters of the laser 2, and enabling the single-pulse energy density of the laser 2 to meet the excitation intensity of the ultrasonic signal under the condition of no damage;
and sixthly, transmitting the ultrasonic signals to a PC (personal computer) terminal 11 for processing through a data acquisition card 10, and analyzing and calculating.
The utility model is suitable for the field of laser ultrasound, and can be used for improving laser excitation signals under the lossless condition of laser ultrasound.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (9)
1. A non-destructive inspection system for enhancing laser ultrasonic signal based on beam shaping, comprising: the laser interferometer comprises a laser interferometer (1), a data processor electrically connected with the laser interferometer (1), and a laser (2), a beam expander (3), a plano-convex conical lens (4), an optical lens group (5), a focusing mirror (6), a total reflection mirror (7) and a vibrating mirror (8) which are sequentially arranged along a light path propagation path.
2. The nondestructive testing system for improving the laser ultrasonic signal based on the beam shaping as claimed in claim 1 wherein the laser beam emitted by the laser (2) forms a spot size of 8mm to 12mm after passing through the beam expander (3).
3. The nondestructive testing system for improving laser ultrasonic signals based on beam shaping as claimed in claim 2 wherein the spot shaped by the plano-convex cone lens (4) to the laser beam is a circular ring with a roundness of more than 92%.
4. The nondestructive testing system for improving laser ultrasonic signals based on beam shaping as claimed in claim 1 wherein the adjustable magnification of the beam expanding lens (3) is 1-10 times.
5. The non-destructive testing system for improving laser ultrasonic signal based on beam shaping as claimed in claim 1, wherein said laser (2) emits laser light with single pulse energy density greater than 200uJ/cm2The laser frequency is 1 kHz-100 kHz.
6. The system for nondestructive testing of laser-based ultrasonic signal enhancement based on beam shaping as set forth in claim 1 wherein the return signal strength of the laser interferometer (1) is greater than 60%.
7. The system for nondestructive testing of laser ultrasonic signal enhancement based on beam shaping as claimed in claim 1 wherein said data processor comprises a gain amplifier (9), a data acquisition card (10) and a PC terminal (11), said laser interferometer (1), said gain amplifier (9), said data acquisition card (10) and said PC terminal (11) being electrically connected in sequence.
8. The non-destructive testing system for improving laser ultrasonic signal based on beam shaping as claimed in claim 7, wherein said gain amplifier (9) has an adjustment value of 10dB to 60 dB.
9. The system for nondestructive testing of laser ultrasound signal enhancement based on beam shaping as set forth in claim 8 wherein said data acquisition card (10) has a sampling rate of 50MS/s or greater.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121734279.8U CN215375237U (en) | 2021-07-28 | 2021-07-28 | Nondestructive testing system for improving laser ultrasonic signal based on beam shaping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121734279.8U CN215375237U (en) | 2021-07-28 | 2021-07-28 | Nondestructive testing system for improving laser ultrasonic signal based on beam shaping |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215375237U true CN215375237U (en) | 2021-12-31 |
Family
ID=79612576
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121734279.8U Active CN215375237U (en) | 2021-07-28 | 2021-07-28 | Nondestructive testing system for improving laser ultrasonic signal based on beam shaping |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215375237U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115389619A (en) * | 2022-08-17 | 2022-11-25 | 北京大学长三角光电科学研究院 | Material defect detection method and device, electronic equipment and computer storage medium |
| CN116079229A (en) * | 2023-03-07 | 2023-05-09 | 长沙麓邦光电科技有限公司 | Point ring laser processing system and processing method thereof |
-
2021
- 2021-07-28 CN CN202121734279.8U patent/CN215375237U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115389619A (en) * | 2022-08-17 | 2022-11-25 | 北京大学长三角光电科学研究院 | Material defect detection method and device, electronic equipment and computer storage medium |
| CN116079229A (en) * | 2023-03-07 | 2023-05-09 | 长沙麓邦光电科技有限公司 | Point ring laser processing system and processing method thereof |
| CN116079229B (en) * | 2023-03-07 | 2023-07-21 | 长沙麓邦光电科技有限公司 | Point ring laser processing system and processing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN215375237U (en) | Nondestructive testing system for improving laser ultrasonic signal based on beam shaping | |
| CN103808802B (en) | A kind of ultrasonic assay method of full optical lasers of material internal defect | |
| CN110763764A (en) | A New Ultrasonic Detection System for Metal Internal Defects | |
| CN108168747A (en) | A kind of workpiece surface residual stress measurement devices and methods therefor based on laser-ultrasound | |
| CN111830134A (en) | An ultrasonic nondestructive testing system | |
| CN106990172B (en) | A kind of ultrasound detection and imaging method and its system | |
| CN110779990B (en) | Laser ultrasonic three-dimensional positioning quantitative detection method for multiple defects in material | |
| CN109682759B (en) | A laser ultrasonic excitation and detection system and method for realizing fast ultrasonic scanning and fixed-point focusing | |
| CN211179651U (en) | A New Ultrasonic Detection System for Metal Internal Defects | |
| CN111257236A (en) | Double-pulse laser ultrasonic detection device and detection method thereof | |
| CN107167518A (en) | Loop laser electromagnetic acoustic focusing probe | |
| Stratoudaki et al. | Adapting the full matrix capture and the total focusing method to laser ultrasonics for remote non destructive testing | |
| Stratoudaki et al. | Full matrix capture and the total focusing imaging algorithm using laser induced ultrasonic phased arrays | |
| CN111751448A (en) | A leaky surface wave ultrasonic synthetic aperture focusing imaging method | |
| CN113155967A (en) | Phased array nonlinear laser ultrasonic detection system | |
| JP5391375B2 (en) | Plate thickness measuring method and plate thickness measuring apparatus | |
| CN112362732B (en) | Free-form surface defect detection method and system based on laser ultrasonic elliptical imaging | |
| CN113406003B (en) | Annular beam laser-based ultrasonic synthetic aperture focusing imaging device and method | |
| Xue et al. | Nondestructive testing of internal defects by ring-laser-excited ultrasonic | |
| CN211179645U (en) | Laser ultrasonic all-optical strain clamp nondestructive testing device | |
| CN114414658B (en) | A laser ultrasonic detection method for the depth of microcracks on metal surfaces | |
| CN116124347A (en) | Device and method for detecting residual stress on sample surface by using laser-based ultrasonic excitation surface wave | |
| CN111537444B (en) | A laser ultrasonic nondestructive testing method and system with virtual control of repetition frequency | |
| CN116203128A (en) | Optimization method and system for defect detection based on laser ultrasonic SAFT | |
| JP4027261B2 (en) | Laser ultrasonic generator using multiple beam irradiation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |