Inspection System

Abstract

To provide an inspection system which is downsized and also can evaluate an internal defect and a surface contamination material of an inspection target object.SOLUTION: An inspection system 100 includes a pulse laser 1, a vibration detection laser 2, an optical detector 16, a first evaluation unit 18, a spectroscopic spectrum measurement unit 19, a second evaluation unit 21, a first optical system 3, and a second optical system 8. The first evaluation unit 18 performs an evaluation regarding an inner defect of an inspection target object 4 on the basis of an output signal of the optical detector 16. The second evaluation unit 21 performs an evaluation regarding a surface contamination material of the inspection target object 4 on the basis of the spectroscopic spectrum measured by the spectroscopic spectrum measurement unit 19. The second optical system 8 includes a reflection mirror group 14b and a lens group (a third lens group 10c) for guiding light L3, which is generated from plasma generated from the inspection target object 4 when first laser light L1 is applied on a surface 40 of the inspection target object 4 and propagates in the air, into the spectroscopic spectrum measurement unit 19.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates generally to inspection systems, and more particularly to inspection systems that perform non-contact evaluation of an object under test. [Background technology]

[0002] BACKGROUND ART Conventionally, a laser ultrasonic remote sensing device has been proposed as a non-destructive inspection device that can inspect the presence or absence and depth of internal defects in an object to be inspected, such as a concrete structure or a metal structure (see, for example, Patent Document 1).

[0003] The non-destructive testing device disclosed in Patent Document 1 includes an elastic wave excitation laser that outputs excitation light (impact beam) consisting of pulsed laser light for exciting elastic waves (ultrasound waves) in an object to be tested, a detection laser that outputs signal light (probe beam) consisting of continuous output laser light, and a movable mirror that scans the signal light over the surface of the object to be tested. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-147813 Summary of the Invention [Problem to be solved by the invention]

[0005] Non-destructive inspection devices that inspect for internal defects in inspection objects can inspect for internal defects, but cannot inspect for surface contaminants in the inspection objects.

[0006] An object of the present disclosure is to provide an inspection system that can evaluate both internal defects and surface contaminants of an object to be inspected while being miniaturized. [Means for solving the problem]

[0007] An inspection system according to one aspect of the present disclosure includes a pulsed laser, a vibration detection laser, a photodetector, a first evaluation unit, a spectroscopic measurement unit, a second evaluation unit, a first optical system, and a second optical system. The pulsed laser emits a first laser beam for vibrating a surface of an object to be inspected. The vibration detection laser emits a second laser beam for detecting vibrations of the surface of the object to be inspected. The photodetector detects probe light and reference light formed by the second laser beam. The first evaluation unit evaluates internal defects of the object to be inspected based on an output signal from the photodetector. The second evaluation unit evaluates surface contaminants of the object to be inspected based on the spectroscopic spectrum measured by the spectroscopic measurement unit. The first optical system includes a group of mirrors for guiding both the first laser beam and the second laser beam to the surface of the object to be inspected. The first optical system is configured to form a first optical path that guides the first laser light to the inspection object, a second optical path that guides the second laser light to the inspection object, a third optical path that guides the probe light, which is reflected light of the second laser light irradiated onto the surface of the inspection object, to the photodetector, and a fourth optical path that guides the reference light, which is a part of the second laser light emitted from the vibration detection laser, to the photodetector. The second optical system includes a group of reflecting mirrors and a group of lenses that guide light that is generated by plasma generated from the inspection object when the surface of the inspection object is irradiated with the first laser light and propagates through air to the spectrum measurement unit. The first optical system further includes a first control device that controls the position and orientation of the mirror group. The second optical system further includes a second control device that controls the position and orientation of the reflecting mirror group. The second control device controls the position and orientation of the reflecting mirror group based on control information for the mirror group from the first control device. An inspection system according to one aspect of the present disclosure includes a pulsed laser, a vibration detection laser, a photodetector, a first evaluation unit, a spectroscopic measurement unit, a second evaluation unit, a first optical system, and a second optical system. The pulsed laser emits a first laser beam for vibrating a surface of an object to be inspected. The vibration detection laser emits a second laser beam for detecting vibrations of the surface of the object to be inspected. The photodetector detects probe light and reference light formed by the second laser beam. The first evaluation unit evaluates internal defects of the object to be inspected based on an output signal from the photodetector. The second evaluation unit evaluates surface contaminants of the object to be inspected based on the spectroscopic spectrum measured by the spectroscopic measurement unit. The first optical system includes a group of mirrors for guiding both the first laser beam and the second laser beam to the surface of the object to be inspected. The first optical system is configured to form a first optical path that guides the first laser light to the inspection object, a second optical path that guides the second laser light to the inspection object, a third optical path that guides the probe light, which is reflected light of the second laser light irradiated onto the surface of the inspection object, to the photodetector, and a fourth optical path that guides the reference light, which is a part of the second laser light emitted from the vibration detection laser, to the photodetector. The second optical system includes a group of reflecting mirrors and a group of lenses that guide light that is generated by plasma generated from the inspection object when the surface of the inspection object is irradiated with the first laser light and propagates through the air to the spectrum measurement unit. The inspection system further includes a controller. The first optical system further includes a first control device that controls the position and orientation of the mirror group. The second optical system further includes a second control device that controls the position and orientation of the reflecting mirror group. The controller causes the second control device to control the reflecting mirror group when causing the first control device to control the mirror group. [Effects of the Invention]

[0008] The inspection system of the present disclosure makes it possible to evaluate both internal defects and surface contaminants of an object to be inspected while achieving miniaturization. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a configuration diagram of an inspection system according to an embodiment. [Figure 2]FIG. 2 is a diagram showing the optical spectrum of plasma generated when concrete not containing salt is irradiated with the first laser beam. [Figure 3] FIG. 3 is a diagram showing the optical spectrum of plasma generated when concrete containing salt is irradiated with the first laser beam. [Figure 4] FIG. 4 is a graph showing the relationship between the amount of salt and the Na luminescence intensity / Ca luminescence intensity. DETAILED DESCRIPTION OF THE INVENTION

[0010] The drawings described in the following embodiments and the like are schematic drawings, and the ratios of the sizes and thicknesses of the components in the drawings do not necessarily reflect the actual dimensional ratios.

[0011] (Embodiment) An inspection system 100 according to the embodiment will be described below with reference to FIG.

[0012] The inspection system 100 is used, for example, for real-time non-destructive inspection of an inspection object 4. The inspection object 4 is, for example, a civil engineering structure. The civil engineering structure is, for example, concrete (concrete structure), but is not limited to concrete. The concrete may be concrete for bridges, concrete for tunnels, etc., but is not limited to these.

[0013] The inspection system 100 inspects the inspection object 4 for internal defects by irradiating the inspection object 4 with a first laser light L1 emitted from a pulsed laser 1 to generate vibrations on the surface of the inspection object 4, and then irradiating the inspection object 4 with a second laser light L2 from a vibration detection laser 2 including a CW laser to detect the vibrations of the inspection object 4. The vibration characteristics of the inspection object 4 caused by the first laser light L1 provide information about the state of the inspection object 4 (e.g., the presence or absence, size, position, etc. of defects). The probe light L21 obtained by reflecting and modulating the second laser light L2 on the surface 40 of the inspection object 4 is signal light containing information about the vibrations.

[0014] In addition, the inspection system 100 inspects the surface contaminants of the object to be inspected 4 from the spectroscopic spectrum of light generated by plasma generated in the object to be inspected 4 when the first laser light L1 emitted from the pulse laser 1 is irradiated onto the object to be inspected 4.

[0015] (1) Inspection system configuration As shown in FIG. 1, the inspection system 100 includes a pulsed laser 1, a vibration detection laser 2, a first optical system 3, a defect evaluation device 6 including a photodetector 16 and a first evaluation unit 18, a spectroscopic analysis evaluation device 9 including a spectroscopic measurement unit 19 and a second evaluation unit 21, and a second optical system 8.

[0016] (1.1) Pulsed laser The pulsed laser 1 emits a first laser light L1. The first laser light L1 is, for example, a laser light for exciting shock waves to vibrate the surface 40 of the inspection object 4. The first laser light L1 is a pulsed laser light. The pulsed laser 1 employs, for example, an Nd:YAG laser (fundamental wave) that outputs pulsed laser light with a pulse width of 10 ns, but is not limited to this.

[0017] (1.2) Vibration detection laser The vibration detecting laser 2 emits a second laser light L2. The second laser light L2 is used, for example, to detect vibrations on the surface 40 of the inspection object 4. In the inspection system 100, the reflected light of the second laser light L2 from the inspection object 4 is used as the probe light L21. The vibration detecting laser 2 includes, for example, a CW laser. The vibration detecting laser 2 employs, for example, an Nd:YAG laser (second harmonic) that continuously outputs laser light with a wavelength of 532 nm, but is not limited to this.

[0018] (1.3) First optical system The first optical system 3 includes a first lens group 10a, a dichroic mirror 13a, a mirror group 14a, and a first control device 15a. The mirror group 14a includes a reflecting mirror 14ab, a dichroic mirror 14aa, and a reflecting mirror 14ac. The first optical system 3 also includes a second lens group 10b, a half mirror 13b, a reflecting mirror 13c, a half mirror 13d, and a half mirror 13e. The first optical system 3 also includes a rangefinder 11 that measures the distance to the surface 40 of the inspection target 4, and a first lens control device 12a.

[0019] In the first optical system 3, the first lens group 10a, the dichroic mirror 13a, and the dichroic mirror 14aa are arranged in this order from the pulse laser 1 side on the optical axis of the pulse laser 1. Also, in the first optical system 3, the half mirror 13d, the second lens group 10b, the half mirror 13b, and the reflecting mirror 14ac are arranged in this order from the vibration detecting laser 2 side on the optical axis of the vibration detecting laser 2. Also, in the first optical system 3, the half mirror 13e and the reflecting mirror 13c are arranged in this order from the photodetector 16 side.

[0020] The first lens group 10a is a lens group for collecting the first laser light L1 emitted from the pulse laser 1, and includes a plurality of first lenses.

[0021] The dichroic mirror 13a transmits the first laser light L1 focused by the first lens group 10a. The dichroic mirror 13a also reflects reflected light L11 of the first laser light L1 reflected by the surface 40 of the inspection object 4. The reflected light L11 is reflected by the reflecting mirror 14ab and the dichroic mirror 14aa, and is incident on the dichroic mirror 13a from the side opposite to the first lens group 10a, and is reflected by the dichroic mirror 13a toward the rangefinder 11.

[0022] The dichroic mirror 14aa reflects the first laser light L1 that has passed through the dichroic mirror 13a toward the reflecting mirror 14ab. The dichroic mirror 14aa also transmits the second laser light L2 from the vibration detecting laser 2. The dichroic mirror 14aa also transmits the probe light L21.

[0023] The half mirror 13d transmits a part of the second laser light L2 from the vibration detecting laser 2, and reflects at least a part of the remaining light as reference light L22 toward the half mirror 13e.

[0024] The second lens group 10b is a lens group for collecting the second laser light L2 that has passed through the half mirror 13d, and includes a plurality of second lenses.

[0025] The half mirror 13b transmits the second laser light L2 focused by the second lens group 10b. The half mirror 13b also reflects probe light L21, which is reflected light of the second laser light L2 reflected by the surface 40 of the inspection object 4. The probe light L21 is reflected by the reflecting mirror 14ab, passes through the dichroic mirror 14aa, is reflected by the reflecting mirror 14ac, enters the half mirror 13b from the side opposite to the second lens group 10b side, and is reflected by the half mirror 13b toward the reflecting mirror 13c side.

[0026] The reflecting mirror 14ac reflects the second laser light L2 toward the dichroic mirror 14aa, and also reflects the probe light L21 toward the half mirror 13b.

[0027] The reflecting mirror 14ab reflects the first laser light L1 and the second laser light L2 toward the inspection object 4. The reflecting mirror 14ab also reflects the reflected light L11 and the probe light L21 from the inspection object 4 side toward the dichroic mirror 14aa.

[0028] The reflecting mirror 13c reflects the probe light L21 from the half mirror 13b side toward the half mirror 13e.

[0029] The half mirror 13e transmits the probe light L21 from the reflecting mirror 13c side, and also reflects the reference light L22 from the half mirror 13d side toward the photodetector 16.

[0030] The first control device 15a controls the position and orientation of the mirror group 14a. More specifically, the first control device 15a controls the position and orientation of the reflecting mirror 14ab. This allows the inspection system 100 to scan the first laser light L1 and the second laser light L2 on the surface 40 of the inspection object 4 and change the irradiation positions of the first laser light L1 and the second laser light L2.

[0031] The first lens control device 12a controls the first lens group 10a and the second lens group 10b. This allows the inspection system 100 to change the spot diameter of the first laser light L1 on the surface 40 of the inspection target 4. The first lens control device 12a controls the first lens group 10a and the second lens group 10b based on the distance measurement value of the rangefinder 11. More specifically, the first lens control device 12a controls the position of the first lens group 10a, the distance between adjacent first lenses among the multiple first lenses in the first lens group 10a, etc. based on the distance measurement value of the rangefinder 11. Furthermore, the first lens control device 12a controls the position of the second lens group 10b, the distance between adjacent second lenses among the multiple second lenses in the second lens group 10b, etc. based on the distance measurement value of the rangefinder 11.

[0032] The first optical system 3 is configured to form a first optical path, a second optical path, a third optical path, and a fourth optical path. The first optical path is an optical path that guides the first laser light L1 emitted from the pulsed laser 1 to the inspection object 4. The second optical path is an optical path that guides the second laser light L2 emitted from the vibration detecting laser 2 to the inspection object 4. The third optical path is an optical path that guides the probe light L21, which is reflected light of the second laser light L2 irradiated onto the surface 40 of the inspection object 4, to the photodetector 16. The fourth optical path is an optical path that guides a portion of the second laser light L2 emitted from the vibration detecting laser 2 to the photodetector 16 as reference light L22.

[0033] The first optical path is formed by the first lens group 10a, the dichroic mirror 14aa, and the reflecting mirror 14ab.

[0034] The second optical path is formed by the second lens group 10b, the reflecting mirror 14ac, and the reflecting mirror 14ab.

[0035] The third optical path is formed by a reflecting mirror 14ab, a reflecting mirror 14ac, a half mirror 13b, and a reflecting mirror 13c.

[0036] The fourth optical path is formed by the half mirror 13d and the half mirror 13e.

[0037] In the first optical system 3, the reflecting mirror 14ab is used to form the first optical path, the second optical path, and the third optical path.

[0038] (1.4) Second optical system The second optical system 8 includes a reflecting mirror group 14b, a third lens group 10c, a second control device 15b, and a second lens control device 12b.

[0039] The reflecting mirror group 14b includes a reflecting mirror 14ba and a reflecting mirror 14bb. In the second optical system 8, the third lens group 10c and the reflecting mirror 14bb are arranged in this order from the spectroscopic spectrum measurement unit 19 side.

[0040] Light L3, which is generated by plasma generated from the inspection object 4 when the first laser light L1 is irradiated onto the surface 40 of the inspection object 4 and propagates through the air, is incident on the reflection mirror 14ba. The reflection mirror 14ba reflects the incident light L3 toward the reflection mirror 14bb.

[0041] The reflecting mirror 14bb reflects the light L3 incident from the reflecting mirror 14ba side toward the third lens group 10c side.

[0042] The third lens group 10c collects the light L3 incident from the reflecting mirror 14bb side. The light L3 collected by the third lens group 10c is incident on the spectroscopic measurement unit 19.

[0043] The second control device 15b controls the position and orientation of the reflecting mirror group 14b. More specifically, the second control device 15b controls the positions and orientations of the reflecting mirrors 14ba and 14bb based on the output of a sensor that detects the light L3 or control information for the mirror group 14a from the first control device 15a. As a result, in the inspection system 100, the second control device 15b can control the reflecting mirror group 14b so that the light L3 is guided to the spectroscopic spectrum measurement unit 19 when the irradiation position of the first laser light L1 on the surface 40 of the inspection target 4 changes.

[0044] The second lens control device 12b controls the third lens group 10c. More specifically, the second lens control device 12b controls the position of the third lens group 10c, the distance between adjacent third lenses among the plurality of third lenses included in the third lens group 10c, and the like, based on the output of a sensor that detects the light L3 or control information for the first lens group 10a from the first lens control device 12a.

[0045] (1.5) Defect evaluation equipment The defect evaluation device 6 evaluates internal defects of the inspection object 4 based on the probe light L21 and reference light L22 propagated by the first optical system 3.

[0046] The defect evaluation device 6 includes a photodetector 16, a frequency analysis unit 17, and a first evaluation unit .

[0047] In the inspection system 100, the first optical system 3 causes the probe light L21 and the reference light L22 to interfere with each other, and the photodetector 16 can measure the vibration of the surface 40 of the inspection object 4.

[0048] The photodetector 16 detects the probe light L21 and the reference light L22 formed by the second laser light L2. More specifically, the photodetector 16 detects interference fringes between the probe light L21 and the reference light L22. The output signal of the photodetector 16 includes a waveform signal that represents a change in the detected intensity of the interference fringes over time.

[0049] The frequency analysis unit 17 performs frequency analysis on the waveform signal output from the photodetector 16. The frequency analysis unit 17 performs frequency analysis using, for example, a fast Fourier transform. Note that the frequency analysis unit 17 is not limited to performing frequency analysis using a fast Fourier transform, and may perform frequency analysis using, for example, a continuous wavelet transform.

[0050] The first evaluation unit 18 evaluates the internal defects of the inspection object 4 based on the output signal of the photodetector 16. More specifically, the first evaluation unit 18 evaluates the presence or absence of internal defects, the size of the internal defects, etc. of the inspection object 4 based on the analysis results of the frequency analysis unit 17. Note that the first evaluation unit 18 may use a trained model to evaluate the presence or absence of internal defects, the size of the internal defects, etc. of the inspection object 4 based on the analysis results of the frequency analysis unit 17.

[0051] The defect evaluation device 6 includes a first computer system. The first computer system is primarily composed of a processor and a memory as hardware. The processor executes a program stored in the memory of the first computer system to realize the functions of the frequency analysis unit 17 and the first evaluation unit 18 of the present disclosure. The program may be pre-stored in the memory of the first computer system, provided via a telecommunications line, or provided in a non-transitory recording medium readable by the first computer system, such as a memory card, an optical disk, or a hard disk drive. The processor of the first computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC). The electronic circuits may be integrated into a single chip or may be distributed across multiple chips. The chips may be integrated into a single device or may be distributed across multiple devices. The first computer system here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit.

[0052] (1.6) Spectroscopic analysis and evaluation equipment The spectroscopic analysis evaluation device 9 includes a spectroscopic measurement unit 19, a spectroscopic analysis unit 20, and a second evaluation unit .

[0053] The optical spectrum measuring unit 19 measures the optical spectrum of light L3 generated by plasma generated in the inspection object 4 when the inspection object 4 is irradiated with the first laser light L1 and guided by the second optical system 8. The optical spectrum measuring unit 19 includes, for example, a spectrophotometer.

[0054] The optical spectrum analysis unit 20 analyzes the optical spectrum measured by the optical spectrum measurement unit 19 .

[0055] The second evaluation unit 21 evaluates the surface contaminants of the inspection object 4 based on the spectrum measured by the spectroscopic measurement unit 19. More specifically, the second evaluation unit 21 evaluates the surface contaminants of the inspection object 4 based on the analysis result of the spectroscopic analysis unit 20.

[0056] The inventors prepared concrete that did not contain salt and concrete that contained salt at various concentrations, and measured the optical spectrum of light generated by plasma generated when the concrete was irradiated with the first laser beam L1. The concrete that did not contain salt was mainly composed of Ca and contained Na as an impurity.

[0057] Figure 2 shows an example of the spectrum of light generated by plasma generated when the first laser light L1 is irradiated onto concrete that does not contain salt, and Figure 3 shows an example of the spectrum of light generated by plasma generated when the first laser light is irradiated onto concrete that does contain salt.

[0058] From Figures 2 and 3, etc., when comparing the spectrum of light L3 generated from concrete that does not contain salt with the spectrum of light L3 generated from concrete that does contain salt, it was found that the spectrum of light L3 generated from concrete that contains salt has a higher Na emission intensity.

[0059] Figure 4 is a graph showing the relationship between the amount of salt and the Na luminescence intensity / Ca luminescence intensity. The Na luminescence intensity / Ca luminescence intensity is the ratio of the Na luminescence intensity to the Ca luminescence intensity. Figure 4 reveals that there is a correlation between the amount of salt contained in concrete and the Na luminescence intensity / Ca luminescence intensity.

[0060] In the inspection system 100, when the inspection target 4 is concrete, the second evaluation unit 21 evaluates the amount of salt contained in the concrete based on, for example, the emission intensity of Na in the spectroscopic spectrum obtained by the spectroscopic measurement unit 19. The second evaluation unit 21 performs a calculation to determine the amount of salt from the emission intensity of Na. When the second evaluation unit 21 performs the above calculation, the greater the emission intensity of Na, the greater the amount of salt that is determined. The second evaluation unit 21 may be configured to evaluate that the concrete surface is contaminated with salt when the emission intensity of Na is greater than a threshold value.

[0061] Furthermore, in the inspection system 100, when the inspection target 4 is concrete, the second evaluation unit 21 may evaluate the amount of salt contained in the concrete based on, for example, the ratio between the emission intensity of Na and the emission intensity of Ca in the spectroscopic spectrum obtained by the spectroscopic measurement unit 19. When the second evaluation unit 21 evaluates the amount of salt contained in the concrete based on the ratio between the emission intensity of Na and the emission intensity of Ca, the salt amount is calculated, for example, from an arithmetic expression corresponding to a calibration curve calculated in advance based on FIG.

[0062] The spectroscopic analysis evaluation device 9 includes a second computer system. The second computer system is mainly composed of a processor and a memory as hardware. The functions of the spectroscopic spectrum analysis unit 20 and the second evaluation unit 21 of the present disclosure are realized by the processor executing a program recorded in the memory of the first computer system. The program may be pre-recorded in the memory of the second computer system, provided via a telecommunications line, or provided by being recorded on a non-transitory recording medium readable by the second computer system, such as a memory card, an optical disk, or a hard disk drive. The processor of the second computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC). The multiple electronic circuits may be integrated into a single chip or may be distributed across multiple chips. The multiple chips may be integrated into a single device or may be distributed across multiple devices. The second computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit.

[0063] (1.7) Other components The inspection system 100 further comprises a housing 30 that houses the first optical system 3 and the second optical system 8 .

[0064] Furthermore, the inspection system 100 may include a display device (e.g., a liquid crystal display) and an input device (e.g., a keyboard, a pointing device) connected to the defect evaluation device 6 and the spectroscopic analysis evaluation device 9. In this case, the user can appropriately operate the input device to display the evaluation results of the defect evaluation device 6, the evaluation results of the spectroscopic analysis evaluation device 9, etc. on the display device.

[0065] (2) Operation of the inspection system In the inspection system 100, a first control device 15a controls the position and orientation of a reflecting mirror 14ab so that the first laser beam L1 and the second laser beam L2 are irradiated onto any desired inspection target area on the surface 40 of the inspection target 4. The first control device 15a is controlled by, for example, a first computer system included in the defect evaluation device 6.

[0066] The inspection system 100 causes a pulsed laser 1 to emit a first laser beam L1, and causes a vibration detecting laser 2 to emit a second laser beam L2. The first laser beam L1 emitted from the pulsed laser 1 passes through a first lens group 10a and a dichroic mirror 13a, and is then reflected by a dichroic mirror 14aa and a reflecting mirror 14ab, and is irradiated onto a surface 40 of an inspection object 4.

[0067] The second laser light L2 emitted from the vibration detection laser 2 passes through the half mirror 13d, the second lens group 10b and the half mirror 13b, is reflected by the reflecting mirror 14ac, passes through the dichroic mirror 14aa, and is then reflected by the reflecting mirror 14ab and irradiated onto the surface 40 of the object to be inspected 4.

[0068] In FIG. 1, the first laser light L1 is schematically indicated by a solid line, and the second laser light L2 is schematically indicated by a dashed dotted line. In the inspection system 100, the mirror group 14a is configured to make the traveling path of the first laser light L1 and the traveling path of the second laser light L2 coincide with each other between the dichroic mirror 14aa and the surface 40 of the inspection object 4. Here, in the inspection system 100, the traveling path of the first laser light L1 and the traveling path of the second laser light L2 can be made coincident with each other between the dichroic mirror 14aa and the surface 40 of the inspection object 4. Therefore, a part of the first optical path and a part of the second optical path can be made common, and the irradiation position of the second laser light L2 and the irradiation position of the first laser light L1 on the surface 40 of the inspection object 4 can be made the same point.

[0069] In the inspection system 100, the second control device 15b controls the position and orientation of the reflection mirror group 14b in accordance with the irradiation positions of the first laser beam L1 and the second laser beam L2 on the surface 40 of the inspection object 4. The second control device 15b is controlled, for example, by at least one of the above-mentioned first computer system and second computer system.

[0070] The inspection system 100 measures the spectrum of light L3 generated by plasma generated in the object to be inspected 4 when the first laser light L1 is irradiated onto the object to be inspected 4 and guided by the second optical system 8 using the spectroscopic measurement unit 19.

[0071] (3) Effects In the inspection system 100 according to the embodiment, the first evaluation unit 18 evaluates internal defects of the inspection object 4 based on the output signal of the photodetector 16, while the second evaluation unit 21 evaluates surface contaminants of the inspection object 4 based on the spectroscopic spectrum measured by the spectroscopic spectrum measurement unit 19. The first optical system 3 includes a reflecting mirror 14ab that reflects both the first laser beam L1 and the second laser beam L2 toward the surface 40 of the inspection object 4. The second optical system 8 includes a reflecting mirror group 14b and a third lens group 10c (lens group) that guide light L3, which is generated by plasma generated from the inspection object 4 when the surface 40 of the inspection object 4 is irradiated with the first laser beam L1 and propagates through the air, to the spectroscopic spectrum measurement unit 19. Thus, the inspection system 100 according to the embodiment can be miniaturized while evaluating both internal defects and surface contaminants of the inspection object 4. In the inspection system 100, a first laser light L1 emitted from a pulsed laser 1 is used to generate vibrations in the object to be inspected 4, and at the same time light L3 is generated from plasma, and a second laser light L2 from a vibration detection laser 2 is used to obtain probe light L21 and reference light L22, while the light L3 is guided to the spectroscopic measurement unit 19 by a second optical system 8. Therefore, there is no need to provide a dedicated laser for generating plasma for evaluating surface contaminants on the object to be inspected, and it is possible to simultaneously (in real time) evaluate internal defects and surface contaminants on the object to be inspected 4 while achieving compactness.

[0072] (4) Variations The above embodiment is merely one of various embodiments of the present disclosure, and various modifications can be made to the above embodiment depending on the design and the like as long as the object of the present disclosure can be achieved.

[0073] For example, the first optical system 3 is not limited to the example configuration shown in FIG. 1, as long as it is configured to be able to form the first, second, third and fourth optical paths described above.

[0074] Furthermore, the inspection system 100 may further include a controller that controls the first control device 15a and the second control device 15b. When the controller controls the mirror group 14a using the first control device 15a, the controller controls the reflecting mirror group 14b using the second control device 15b. As a result, in the inspection system 100, the controller collectively controls the first control device 15a and the second control device 15b, so that the second control device 15b can control the reflecting mirror group 14b so that the light L3 is guided to the spectroscopic measurement unit 19 even if the irradiation position of the first laser light L1 on the surface 40 of the inspection target 4 is changed.

[0075] Furthermore, in the inspection system 100, the first control device 15a is included in the first optical system 3, but it may be provided separately from the first optical system 3.

[0076] In addition, in the inspection system 100, the second control device 15b is included in the second optical system 8, but may be provided separately from the second optical system 8.

[0077] Furthermore, the second evaluation unit 21 may not only evaluate the surface contaminants of the inspection object 4 based on the spectrum measured by the spectroscopic measurement unit 19, but may also evaluate the composition of the inspection object.

[0078] (Aspect) The present specification discloses the following aspects.

[0079] An inspection system (100) according to a first aspect includes a pulsed laser (1), a vibration detecting laser (2), a photodetector (16), a first evaluation unit (18), a spectroscopic spectrometer (19), a second evaluation unit (21), a first optical system (3), and a second optical system (8). The pulsed laser (1) emits a first laser beam (L1) for vibrating a surface (40) of an inspection object (4). The vibration detecting laser (2) emits a second laser beam (L2) for detecting vibration of the surface (40) of the inspection object (4). The photodetector (16) detects a probe beam (L21) and a reference beam (L22) formed by the second laser beam (L2). The first evaluation unit (18) evaluates internal defects of the inspection object (4) based on an output signal from the photodetector (16). The second evaluation unit (21) evaluates surface contaminants on the inspection object (4) based on the spectrum measured by the spectroscopic measurement unit (19). The first optical system (3) includes a mirror group (14a) for guiding both the first laser light (L1) and the second laser light (L2) to the surface (40) of the inspection object (4). The first optical system (3) is configured to form a first optical path that guides the first laser light (L1) to the inspection object (4), a second optical path that guides the second laser light (L2) to the inspection object (4), a third optical path that guides probe light (L21), which is reflected light of the second laser light (L2) irradiated onto the surface (40) of the inspection object (4), to the photodetector (16), and a fourth optical path that guides reference light (L22), which is a part of the second laser light (L2) emitted from the vibration detection laser (2), to the photodetector (16). The second optical system (8) includes a group of reflecting mirrors (14b) and a group of lenses (third lens group 10c) for guiding light (L3) that is generated by plasma generated from the object to be inspected (4) when the surface (40) of the object to be inspected (4) is irradiated with the first laser light (L1) and that propagates through the air to the spectroscopic measurement unit (19).

[0080] According to this aspect, it is possible to evaluate both internal defects and surface contaminants of the inspection object (4) while achieving miniaturization.

[0081] In the inspection system (100) according to the second aspect, in the first aspect, the first optical system (3) further includes a first control device (15a) that controls the position and orientation of the mirror group (14a). The second optical system (8) further includes a second control device (15b) that controls the position and orientation of the reflecting mirror group (14b). The second control device (15b) controls the position and orientation of the reflecting mirror group (14b) based on control information for the mirror group (14a) from the first control device (15a).

[0082] According to this aspect, when the irradiation positions of the first laser light (L1) and the second laser light (L2) on the surface (40) of the inspection object (4) are scanned, it is possible to control the group of reflecting mirrors (14b) in accordance with the change in the irradiation position of the first laser light (L1), and it is possible to automatically guide the light (L3) to the spectroscopic measurement unit (19).

[0083] The inspection system (100) according to the third aspect is the same as that according to the first aspect, but further includes a controller. The first optical system (3) further includes a first control device (15a) that controls the position and orientation of the mirror group (14a). The second optical system (8) further includes a second control device (15b) that controls the position and orientation of the reflecting mirror group (14b). When the controller controls the mirror group (14a) using the first control device (15a), the controller controls the reflecting mirror group (14b) using the second control device (15b).

[0084] According to this aspect, when the irradiation positions of the first laser light (L1) and the second laser light (L2) on the surface (40) of the inspection object (4) are scanned, it is possible to control the group of reflecting mirrors (14b) in accordance with the change in the irradiation position of the first laser light (L1), and it is possible to automatically guide the light (L3) to the spectroscopic measurement unit (19).

[0085] The inspection system (100) according to the fourth aspect is the inspection system according to the first or second aspect, further comprising a housing (30) that houses the first optical system (3) and the second optical system (8).

[0086] According to this aspect, it is possible to achieve miniaturization.

[0087] In the inspection system (100) according to the fifth aspect, in the first or second aspect, the inspection object (4) is concrete. The second evaluation unit (21) evaluates the amount of salt contained in the concrete based on the emission intensity of Na in the spectroscopic spectrum obtained by the spectroscopic measurement unit (19).

[0088] According to this embodiment, it is possible to evaluate the amount of salt contained in the concrete, which is the inspection object (4).

[0089] In the inspection system (100) according to the sixth aspect, in the first or second aspect, the inspection object (4) is concrete. The second evaluation unit (21) evaluates the amount of salt contained in the concrete based on the ratio of the luminescence intensity of Na to the luminescence intensity of Ca in the spectroscopic spectrum obtained by the spectroscopic measurement unit (19).

[0090] According to this embodiment, it is possible to evaluate the amount of salt contained in the concrete, which is the inspection object (4).

[0091] In the inspection system (100) according to the seventh aspect, in any one of the first to sixth aspects, the mirror group (14a) is configured to align the traveling path of the first laser light (L1) and the traveling path of the second laser light (L2) with each other between the surface (40) of the object to be inspected (4).

[0092] According to this aspect, the first optical system (3) can be made smaller, and the inspection system (100) can be made even smaller. [Explanation of symbols]

[0093] 1. Pulse laser 2. Vibration detection laser 3 First optical system 4. Inspection object 40 surface 6. Defect evaluation equipment 8 Second optical system 9. Spectroscopic analysis and evaluation equipment 10a First lens group 10b Second lens group 10c Third lens group (lens group) 11 Rangefinder 12a First lens control device 12b Second lens control device 13a Dichroic mirror 13b Half Mirror 13c Reflective mirror 13d Half Mirror 13e Half Mirror 14a Mirror Group 14aa Dichroic mirror 14ab Reflective mirror 14ac Reflective Mirror 14b Reflecting mirror group 14ba Reflective mirror 14bb Reflective Mirror 15a First control device 15b Second control device 16 Photodetector 17 Frequency analysis section 18 First Evaluation Section 19 Spectroscopic measurement section 20 Spectroscopic analysis section 21 Second Evaluation Section 30 Case L1 First laser beam L2 Second laser beam L21 probe light L22 reference light L3 Light

Claims

1. a pulsed laser that emits a first laser beam for vibrating a surface of an inspection object; a vibration detection laser that emits a second laser beam for detecting vibrations on the surface of the inspection object; a photodetector for detecting probe light and reference light formed by the second laser light; a first evaluation unit that evaluates internal defects of the inspection object based on an output signal from the photodetector; a spectroscopic measurement unit; a second evaluation unit that evaluates surface contaminants of the inspection object based on the spectrum measured by the spectroscopic measurement unit; a first optical system including a group of mirrors for guiding both the first laser light and the second laser light to the surface of the inspection object; a second optical system, The first optical system is a first optical path that guides the first laser light to the inspection object; a second optical path that guides the second laser light to the inspection object; a third optical path that guides the probe light, which is reflected light of the second laser light irradiated onto the surface of the inspection object, to the photodetector; a fourth optical path that guides the reference light, which is a part of the second laser light emitted from the vibration detection laser, to the photodetector, the second optical system includes a group of reflecting mirrors and a group of lenses for guiding light, which is generated by plasma generated from the inspection object when the surface of the inspection object is irradiated with the first laser light and which propagates through air, to the spectroscopic spectrum measurement unit; the first optical system further includes a first control device that controls a position and an orientation of the mirror group; the second optical system further includes a second control device that controls a position and an orientation of the group of reflecting mirrors, the second control device controls the position and orientation of the group of reflecting mirrors based on control information of the group of mirrors from the first control device; Inspection system.

2. A pulsed laser that emits a first laser beam for vibrating the surface of an object to be inspected; a vibration detection laser that emits a second laser beam for detecting vibrations on the surface of the inspection object; a photodetector for detecting probe light and reference light formed by the second laser light; a first evaluation unit that evaluates internal defects of the inspection object based on an output signal from the photodetector; a spectroscopic measurement unit; a second evaluation unit that evaluates surface contaminants of the inspection object based on the spectrum measured by the spectroscopic measurement unit; a first optical system including a group of mirrors for guiding both the first laser light and the second laser light to the surface of the inspection object; a second optical system, The first optical system is a first optical path that guides the first laser light to the inspection object; a second optical path that guides the second laser light to the inspection object; a third optical path that guides the probe light, which is reflected light of the second laser light irradiated onto the surface of the inspection object, to the photodetector; a fourth optical path that guides the reference light, which is a part of the second laser light emitted from the vibration detection laser, to the photodetector, the second optical system includes a group of reflecting mirrors and a group of lenses for guiding light, which is generated by plasma generated from the inspection object when the surface of the inspection object is irradiated with the first laser light and which propagates through air, to the spectroscopic spectrum measurement unit; Further comprising a controller, the first optical system further includes a first control device that controls a position and an orientation of the mirror group; the second optical system further includes a second control device that controls a position and an orientation of the group of reflecting mirrors, the controller causes the second control device to control the group of reflecting mirrors when causing the first control device to control the group of mirrors; Inspection system.

3. Further comprising a housing that houses the first optical system and the second optical system.

3. The inspection system according to claim 1 or 2.

4. The inspection object is concrete, The second evaluation unit evaluates the amount of salt contained in the concrete based on the emission intensity of Na in the spectroscopic spectrum.

3. The inspection system according to claim 1 or 2.

5. The inspection object is concrete, The second evaluation unit evaluates the amount of salt contained in the concrete based on a ratio of an emission intensity of Na to an emission intensity of Ca in the spectroscopic spectrum.

3. The inspection system according to claim 1 or 2.

6. The group of mirrors is configured to match the traveling path of the first laser light with the traveling path of the second laser light between the surface of the object to be inspected.

3. The inspection system according to claim 1 or 2.

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