JP2020085770A - Scattered light detection device, and nondestructive inspection device using the same - Google Patents

Abstract

To provide a scattered light detection device which realizes highly accurate scattered light measurement by removing noise of shape information mixed in a signal.SOLUTION: A scattered light detection device 11 uses an electromagnetic wave belonging to any of gamma rays, X-rays, ultraviolet rays, visible rays, infrared rays, and microwaves as irradiation light 5, and which analyzes a molecular structure of a specimen 4 on the basis of a result of measuring scattered light from the specimen 4 received the irradiation light 5. The scattered light detection device includes: a generation source 3 of the irradiation light 5; a first detector 1 arranged in an emission direction forming an acute angle with respect to an incident direction of the irradiation light 5 on the basis of the specimen 4; and a second detector 2 arranged in the emission direction of an angle different from the acute angle with respect to the incident direction. The scattered light detection device measures light having a first wavelength among the scattered light by the first detector 1, measures light having a second wavelength different from the first wavelength among the scattered light by the second detector 2, and quantitatively measures while canceling shape information of the specimen 4 using an output ratio of the first detector 1 and the second detector 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a scattered light detection device and a non-destructive inspection device using the same, and in particular, irradiating a test object with light typified by near-infrared light and measuring scattered light reflected by the test object to measure the test object. The present invention relates to a scattered light detection device that can be used to quantify the degree of deterioration and a nondestructive inspection device that nondestructively inspects an object using the scattered light detection device.

There is a great need for non-destructive inspection of the inside of an object, and various technologies such as X-ray, ultrasonic wave, magnetism, laser, infrared ray have been developed in the medical and industrial fields. For example, a medical device is known in which the principle of Raman spectroscopy is applied to enable measurement of a living sample (Patent Document 1). In an industrial field different from this medical device, there are an unlimited number of nondestructive tests for deterioration inspection of industrial devices. The targets of nondestructive inspection are mainly changes in internal structure and deterioration of internal elements due to deterioration. The change in quality includes rust, oxidation, dirt, mixing, curing, drying, etc., which cause deterioration such as cracks, voids, scratches, discoloration, and abrasion on the object.

Since the bearing of the elevator is enclosed in the case, it is difficult to directly observe the deterioration of the bearing unless it is disassembled for replacement or repair. Therefore, a technique for diagnosing the deterioration of the bearing has been developed by measuring the vibration generated by the change in the rotation of the bearing outside the bearing case (Non-Patent Documents 1-3). In addition, a technique has also been developed for detecting an abnormal rotation occurring in a bearing by using rotation information obtained from a high resolution rotation sensor (encoder) incorporated in the bearing (Non-Patent Document 4).

However, the vibration caused by the abnormality of the bearing is weak, and it is difficult to measure due to the disturbance such as noise and vibration generated from the surrounding devices. To solve this problem, a measuring device for magnetically measuring the amount of iron powder generated by scratches or friction in the bearing mixed with grease, that is, a grease iron powder concentration meter has been developed (Non-Patent Document 5).

In addition, a technique for estimating deterioration due to a change in the color of grease caused by the mixing of iron powder, that is, a lubricating oil diagnosis technique based on RGB hues using a membrane patch has been developed (Non-Patent Document 6). However, the amount of iron powder mixed in the grease of the bearing is small, and the color of the grease changes even if dirt or rust is mixed, so high-precision measurement is difficult. In response to this problem, by irradiating the test object with near-infrared rays, measuring the scattering from the reflected light obtained from the test object, and measuring the deviation from the original wavelength, the alteration of the test object is analyzed by the molecular structure. A scattered light detection device that can be observed as a change in the light source has been developed, and a portable Raman spectroscopic module that is small in size and light in weight with good portability is also known (Non-Patent Document 7).

Japanese Patent Laid-Open No. 2018-13453

https://www.onosokki.co.jp/HP-WK/products/category/vib_relate.htm http://www.tetsugen.com/product/mhc/ http://www.iiu.co.jp/seihin.html#EM_diagnosys https://www.ntn.co.jp/japan/news/new_products/news201700033.html https://www.new-cosmos.co.jp/product/733/ https://www.pwri.go.jp/jpn/results/2015/tokyosc/pdf/5.pdf https://www.hamamatsu.com/jp/ja/product/photometry-systems/raman-spectroscopy/index.html

However, in the conventional near-infrared measurement including the portable Raman spectroscopic module disclosed in Non-Patent Document 7, the amount of wavelength shift is small, and scattered light, that is, noise caused by the surface shape of the test object is generated. Since it mixes with the signal, there is a problem that the measurement accuracy cannot be maintained. The present invention has been made in order to solve such a problem, and an object thereof is to provide a scattered light detection device with high accuracy in scattered light measurement by removing noise of shape information mixed in a signal. To provide.

In order to solve the above problems, the present invention uses an electromagnetic wave belonging to any of gamma rays, X-rays, ultraviolet rays, visible rays, infrared rays, and microwaves as irradiation light, and uses the irradiation light to inspect the object. A scattered light detecting device for analyzing the molecular structure of the test object based on the result of measuring scattered light from the source of the irradiation light, and the incident direction of the irradiation light based on the test object. A first detector arranged in an emission direction that forms an acute angle with respect to the second detector, and a second detector arranged in an emission direction that is different from the acute angle with respect to the incident direction, and Of the scattered light, light having a second wavelength different from the first wavelength is measured by the second detector, and the first detector measures light having a first wavelength. The output ratio between the detector and the second detector is used to perform quantitative measurement while canceling the shape information of the test object.

ADVANTAGE OF THE INVENTION According to this invention, the scattered light detection apparatus which improved the precision of scattered light measurement by removing the noise of the shape information mixed in a signal can be provided.

It is a conceptual diagram which shows the basic example of the scattered light detection apparatus (henceforth "this apparatus") which concerns on one Embodiment of this invention. It is a conceptual diagram which shows the other structural example of this apparatus. It is a conceptual diagram which shows the example of improvement with respect to this apparatus of FIG. It is a conceptual diagram which shows the example of improvement with respect to this apparatus of FIG. It is a conceptual diagram which shows the structural example which replaced the detector with the camera with respect to this apparatus of FIG. It is a conceptual diagram which shows the modification with respect to this apparatus of FIG. It is a conceptual diagram which shows the modification common to this apparatus of FIGS.

Hereinafter, modes for carrying out the present invention will be described in detail by Examples 1 to 7 with reference to FIGS. 1 to 7, respectively.

(Example 1)
FIG. 1 is a conceptual diagram showing a basic example of a scattered light detection device (hereinafter, also referred to as “this device”) according to an embodiment of the present invention. As shown in FIG. 1, the device 11 includes an object 4 to be inspected (hereinafter, also simply referred to as “inspection object 4 ”) 4 and a light source (hereinafter, “ (Also referred to as “source 3”) 3, a half mirror 6 that splits the scattering generated from the test object 4 into two hands, and a wavelength of the first energy that is elastic scattering (hereinafter, also referred to as “first wavelength”). A first energy detector (hereinafter, also simply referred to as “first detector 1”) 1 that measures the light that it has, and a wavelength of a second energy that is inelastic scattering generated from the test object 4 (hereinafter, “the first detector”). A second energy detector (hereinafter, also simply referred to as “second detector 2”) 2 that measures light having two wavelengths).

The generation source 3, the half mirror 6, the first detector 1 and the second detector 2 (hereinafter, also referred to collectively as “detectors 1 and 2”) are arranged on the same side with respect to the inspection object 4. It By arranging them on the same side, the device 11 can be integrated, and a shape in which the device 4 is pressed against the surface of the test object 4 from one side is possible.

The near infrared rays 5 emitted from the generation source 3 are scattered inside the test object 4 and reflected on the same side as the generation source 3. The scattered light is separated by the half mirror 6 and enters the first detector 1 and the second detector 2. Incident light is measured at the detector. When the half mirror 6 is used, scattered light is divided into two parts, a transmitted light 7 that passes through the mirror as it is and a reflected light 8 that is separated in the orthogonal direction. By separating in the orthogonal direction, it becomes easy to arrange the two detectors 1 and 2 close to each other, and the size of the device 11 can be reduced.

In the present apparatus 11, by using the half mirror 6, it is possible to simultaneously measure light having two types of wavelengths, and it is possible to easily perform a process of accurately determining an output ratio of detection signals of two types of light, which will be described later. it can.

Further, if sensors are used for the detectors 1 and 2, the detectors 1 and 2 are downsized, so that the device 11 can be downsized and lightened, and the handling is easy. On the other hand, as described later with reference to FIGS. 5 and 6, if optical cameras (hereinafter, also simply referred to as “cameras”) 25 and 26 are used instead of the detectors 1 and 2, the output is obtained as an image. Therefore, it is possible to measure a wide range at a time, which facilitates observation.

As is known from the principle of Raman spectroscopy, the light having the first wavelength, which is elastic scattering, has no energy change from the original near-infrared light 5 irradiated, is proportional to the number of molecules of the test object 4, and is inelastic. An order of magnitude larger than scatter. On the other hand, the light having the second wavelength that is inelastically scattered causes a wavelength shift from the original near-infrared ray 5 that is irradiated. This wavelength shift is an energy loss and represents a change in the molecular structure or a change in the chemical state as alteration of the test object 4. However, both of them include shape-derived scattering, especially scattering due to surface irregularities.

Light having a first wavelength of elastic scattering is acquired by the first detector 1, and light having a second wavelength of inelastic scattering is acquired by the second detector 2. The output ratio of the output value acquired by the first detector 1 and the output value acquired by the second detector 2 is obtained. At this time, the first detector 1 and the second detector 2 measure in real time scattered light generated simultaneously at the same location on the test object 4. As described above, the output ratio of the two detection outputs derived from the same generation source 3 and divided into the first and second different wavelengths is kept substantially constant as long as the molecular structure of the test object 4 does not change. The principle works.

By this principle, shape information commonly included in both, that is, noise can be canceled. As a result, the unevenness information of the surface shape of the test object 4 is removed, and only the quality information inside the test object 4 is obtained. That is, quantitative measurement is performed while canceling the shape information of the test object 4 by using the output ratio between the first detector 1 and the second detector 2. At this time, when the dynamic range of the measurement level is restricted, it is preferable to consider the maximum value and the minimum value of the measurement output.

That is, since the output value obtained by the first detector 1 is larger, the small output value obtained by the second detector 2 is divided by the larger output value obtained by the first detector 1 to obtain the ratio. When calculated, it will be a small division value. In digital arithmetic processing, if the number to be handled is small, it is effective in preventing overflow. Conversely, when the large output value obtained by the first detector 1 is divided by the small output value obtained by the second detector 2 to obtain the ratio, a large division value is obtained. In the digital arithmetic processing, if the numerical value to be handled is large, it is possible to prevent the value after arithmetic from dropping due to quantization error.

The wavelength of the light emitted from the generation source 3, the detection wavelength of the first detector 1, and the detection wavelength of the second detector 2 are selected according to the object 4 and the detection target. Here, the wavelength of the light generated from the generation source 3 is the same as the first wavelength that is elastic scattering, and the detection wavelength of the first detector 1 is also the same.

For example, when the test object 4 is grease and the detection target is iron powder, the wavelength of the irradiation light 5 from the generation source 3, the first wavelength, and the detection wavelength of the first detector 1 are selected for grease. On the other hand, the second wavelength and the detection wavelength of the second detector 2 are selected for iron powder.

As an example, when the inspection object 4 is a surface rubber of a urethane handrail or an anti-vibration rubber attached to the basket bottom of an elevator and the detection target is a crack, the wavelength of the irradiation light 5 from the generation source 3 and The first wavelength and the detection wavelength of the first detector 1 are selected for rubber, and the second wavelength and the detection wavelength of the second detector 2 are selected for cracks.

As another example, when the inspection object 4 is an escalator step iron frame and the detection target is rust, the wavelength of the irradiation light 5 from the generation source 3, the first wavelength, and the detection wavelength of the first detector 1 are The second wavelength selected for iron and the detection wavelength of the second detector 2 are selected for rust.

If the irradiation light 5 used here is near-infrared light, the light can reach the inside of the object to be inspected 4 and the internal change can be measured. If terahertz waves or X-rays are adopted as the irradiation light 5, the light can reach further inside the object 4 to be measured, and the change in the depth can be measured. In particular, when the near infrared rays 5 are used, the measurement can be facilitated by making the test object 4 into a thin plate shape. The device 11 is suitable for being adopted as an industrially practical inspection tool, particularly as a nondestructive inspection device (main inspection device). By accurately obtaining the output ratio of the detection signals of the two types of light obtained from the first detector 1 and the second detector 2 in the present inspection device, and monitoring whether or not there is a change in the output ratio, The inspection purpose can be realized.

(Example 2)
FIG. 2 is a conceptual diagram showing this device according to another configuration example. As shown in FIG. 2, in the present device 12, two detectors 1 and 2 which were required in the present device 11 according to the first embodiment shown in FIG. (Also referred to as “energy-resolving detector” or simply “detector”) 9. By using this detector 9, it is possible to set a threshold value inside the detector 9 and separate the incident light into the first energy and the second energy for measurement. When such an energy-resolving type detector 9 is used, a plurality of energies can be measured by one unit, so that the number of detectors 9 can be one, and the half mirror 6 is not necessary. Can be made smaller and lighter, resulting in easier handling.

(Example 3)
FIG. 3 is a conceptual diagram showing an improved example of the device 12 of FIG. Since the apparatus 12 according to the second embodiment shown in FIG. 2 is expensive, various improvement examples are proposed with reference to FIG. As shown in FIG. 3, in the present device 13, one detector 10 is provided similarly to the present device 12 according to the second embodiment shown in FIG. 2, and a plurality of filters 21, 22 are provided in front of the detector 10. The detection areas 23 and 24 of the detector 10 are separated for each of the filters 21 and 22. One detector 10 can simultaneously detect the light of the energy transmitted through the plurality of filters 21 and 22.

The two filters 21 and 22 are a first optical filter 21 and a second optical filter 22 described below. First, the first optical filter (also simply referred to as “filter”) 21 preferentially transmits light having elastically scattered first wavelength. The second optical filter (also simply referred to as “filter”) 22 preferentially transmits light having a second wavelength that is inelastic scattering. According to one detector 10 including these two filters 21 and 22, elastic scattering and inelastic scattering can be simultaneously measured. In this way, the detector 10 has a width in the detection wavelength, and thus can measure both the first wavelength and the second wavelength.

As the filters 21 and 22 for such a purpose, a strip-shaped filter 21 and a filter 22 may be attached in a striped shape. Alternatively, a shape in which the filters 21 and 22 are arranged in a grid pattern is also conceivable. The closer the two types of filters 21 and 22 are to each other, the more accurately the ratio can be calculated when obtaining the ratio of elastic scattering and inelastic scattering. That is, the purpose is to know the change in the molecular structure by monitoring whether or not the output ratio of two detection outputs having different wavelengths from the same place has changed.

Further, by arranging and rotating the two types of filters 21 and 22 on the disk, it becomes possible to switch the energy at high speed and easily. Although not shown in detail, if one polarization filter is used instead of the filters 21 and 22, it is possible to switch which of two types of energy is transmitted by changing the inclination of the polarization filter. It will be possible. As described above, the present apparatus 13 according to the third embodiment shown in FIG. 3 has a configuration in which the detector 10 is one and the switchable filters 21 and 22 are arranged in front of the detector 10. If two kinds of energy are transmitted while switching the filters 21 and 22 by using some control mechanism, it is possible to measure a plurality of energies with one detector 10.

(Example 4)
FIG. 4 is a conceptual diagram showing an improved example of the device 11 of FIG. As shown in FIG. 4, in the present device 14, optical filters 21 and 22 are arranged in front of the detectors 1 and 2, respectively. As described above, these are the first optical filter 21 that preferentially transmits the light having the first wavelength, which is the elastic scattering generated from the test object 4, and the inelastic scattering generated from the test object 4. The second optical filter 22 preferentially transmits light having the second wavelength. Since the energy transmitted by these two types of filters 21 and 22 is selected, it is not necessary to select the detection wavelength on the detector side, and the detectors having the same function should be used for the first detector 1 and the second detector 2. You can That is, there is an effect that an expensive one such as the energy decomposition detector 9 used in the present apparatus 12 according to the second embodiment shown in FIG. 2 is unnecessary.

(Example 5)
FIG. 5 is a conceptual diagram showing a configuration example in which a detector is replaced with a camera in the device 14 of FIG. As shown in FIG. 5, in the present device 15, the optical cameras 25 and 26 replaced with the detectors are used, and the optical lens 18 is also attached and used. Since the focus can be adjusted by using the optical lens 18, it is possible to change the distance between the object 4 to be inspected and the cameras 25 and 26 to change the size of the visual field captured by the cameras 25 and 26. it can. When the wavelengths detected by the first optical camera 25 and the second optical camera 26 are close to each other, by disposing one optical lens 18 in front of the half mirror 6, as shown in FIG. Both cameras optical cameras 25, 26 can be accommodated. This device 15 can be miniaturized because only one optical lens 18 is required.

(Example 6)
FIG. 6 is a conceptual diagram showing a modification of the present device 15 of FIG. As shown in FIG. 6, also in the present device 16, as in the present device 15 according to the fifth embodiment shown in FIG. 5, optical cameras 25 and 26 are used instead of the detectors. Furthermore, the point that the dedicated optical lenses 27 and 28 are arranged and used for each of the cameras 25 and 26 is different. Further, two optical lenses are provided behind the half mirror 6 so that they can be easily adapted to each camera. In this way, since the lens and its setting can be optimized for each of the cameras 25 and 26, highly accurate measurement is possible. In particular, the present device 16 is suitable because it exhibits good performance when the difference between the wavelengths detected by the two cameras 25 and 26 is large. It should be noted that although the present apparatus 16 of FIG. 6 and the present apparatus 15 of FIG. 5 are one of the basic types and the other is a modified example, any of the basic types may be used. The apparatus of FIGS. 5 and 6 may have a configuration in which an optical filter is installed in front of the camera and the optical filter is installed between the lens and the camera as in the apparatus of FIG. In that case, as in FIG. 4, it is not necessary to select the detection wavelength on the detector side, and the detectors having the same function can be used for the first detector 1 and the second detector 2. That is, there is an effect that an expensive one such as the energy decomposition detector 9 used in the present apparatus 12 according to the second embodiment shown in FIG. 2 is unnecessary.

(Example 7)
FIG. 7 is a conceptual diagram showing a modification common to the present apparatuses 11 to 16 of FIGS. As shown in FIG. 7, the present device 17 detects the light of the first wavelength and the light of the second wavelength while rotating the test object 4. Alternatively, the object to be inspected 4 is fixed, and the light having the first wavelength and the light having the second wavelength are detected while rotating the detection device. The form of the detection device can be applied to any of the present devices 11 to 16 (hereinafter collectively referred to as “detection device”) according to the first to sixth embodiments described above with reference to FIGS. 1 to 6. By obtaining the ratio of the light of the first wavelength and the light of the second wavelength and performing the reconstruction process, it is possible to obtain a cross-sectional image and observe the state of three-dimensional alteration. When two detectors or cameras (hereinafter, abbreviated as “camera”) are used in the above-described detection device, one camera captures the entire object 4 and the other camera is used for internal observation. You can also take pictures of limited areas. By observing the ratio of the light of the first wavelength and the light of the second wavelength only in the limited area and displaying the ratio on the whole image, the deterioration of the periphery of the detection target is observed while grasping the whole of the test object 4. be able to.

The detection device described above has an attached processing mechanism. In the processing mechanism, the value of the ratio of the light of the first wavelength and the light of the second wavelength is subjected to clustering processing, and it is possible to determine whether it is abnormal or normal. GMM (Gaussian Mixture Model) or EM (Expectation maximization) algorithm is used for the clustering process. Since non-metals have a property of easily absorbing mid-infrared rays and far-infrared rays, when the first wavelength is visible light or near-infrared ray and the second wavelength is mid-infrared ray or far-infrared ray, metal and non-metal are distinguished. Suitable for when. For example, the distinction between non-metal grease and iron powder that is metal mixed in the grease corresponds to this. When observing the alteration of the object to be inspected 4, the ratio of the light of the first wavelength and the light of the second wavelength obtained in the area where the object to be inspected 4 has no alteration and the area in which the object to be inspected 4 has alteration It is desirable that the difference between the first wavelength light and the second wavelength light is large. For example, when the difference between the light of the first wavelength and the second wavelength is small in the region where the inspection object 4 is not changed, and the difference between the light of the first wavelength and the second wavelength is large in the region where the inspection object 4 is changed. Alternatively, the difference between the light of the first wavelength and the second wavelength is large in the region where the inspection object 4 is not altered, and the difference between the light of the first wavelength and the second wavelength is small in the region where the inspection object 4 is altered. Or the magnitudes of the light of the first wavelength and the second wavelength in the region where there is no alteration of the test object 4 and the magnitudes of the light of the first wavelength and the second wavelength in the region where the test object 4 is altered are reversed. If you do, it is realized by. When the inspection object 4 is an iron frame and the deterioration of the frame such as corrosion, rust and oxidation is observed, or when the inspection object 4 is rubber and the deterioration of the rubber is hardened by ultraviolet rays or heat. Is equivalent to this.

In the detection device described above, the irradiation light 5 from the generation source 3 has been described by using near infrared rays as a representative example, but the present invention is not limited to this. It can be applied to waves having various wavelengths such as visible light, infrared rays, ultraviolet rays, X-rays, microwaves, millimeter waves, and terahertz waves. Depending on these cases, a detector capable of measuring the energy to be detected and a filter capable of transmitting the energy to be detected are used for each source 3.

As a typical example, it is possible to measure the degree of deterioration based on the amount of iron powder mixed in with high accuracy and quantitatively, and observe changes in the quality of the grease 4 and other test objects 4. Therefore, the scattering is separated into Raman scattering which is inelastic scattering and Rayleigh scattering which is elastic scattering, and the measurement is performed, and the shape information, that is, noise is canceled and quantitative measurement is performed by obtaining the ratio of the inelastic scattering and elastic scattering. Is possible. According to the scattered light detection device (present device) 11 to 17 according to the present invention or the nondestructive inspection device (present inspection device) according to the present invention, it is possible to improve accuracy by removing the noise of the shape information included in the signal. The scattered light measurement can be realized. Hereinafter, the main points of the present invention will be described with reference to the claims.
[1] Scattered light detection devices (present devices) 11 to 17 shown in FIGS. 1 to 7 are molecules of the test object 4 based on the results of measurement of scattered light from the test object 4 which receives the irradiation light 5. It is a measuring instrument for analyzing the structure and an industrially practical inspection tool. As an example of the object 4 to be inspected, grease enclosed in a bearing is suitable, and is suitable as an inspection tool for determining the degree of deterioration thereof.

The irradiation light 5 used in the present devices 11 to 17 may be ultraviolet light, visible light, near infrared light, mid infrared light, or far infrared light. Near infrared rays 5 are particularly preferable. Further, depending on the use of the present devices 11 to 17, electromagnetic waves belonging to any of gamma rays, X-rays, or microwaves may be regarded as the irradiation light 5 and used. In particular, gamma rays or X-rays are suitable for applications that require penetrating power to reach a deep portion of the test object 4. For other uses, mid-infrared rays and far-infrared rays are safe, convenient, and easy to use.

The present devices 11 to 17 are configured to include a generation source 3 of irradiation light 5, a first detector 1, and a second detector 2. The first detector 1 is arranged in an emitting direction that forms an acute angle with respect to the incident direction of the irradiation light 5 with respect to the test object 4. The second detector 2 is arranged in an emitting direction having an angle different from an acute angle with respect to the incident direction, for example, an emitting direction forming an obtuse angle with respect to the incident direction. The first detector 1 measures the light having the first wavelength among the scattered light generated by the irradiation light 5 being scattered by the test object 4. The second detector 2 measures light having a second wavelength different from the first wavelength among the light generated by the irradiation light 5 being scattered by the test object 4.

The present devices 11 to 17 perform quantitative measurement while canceling the shape information of the test object 4 by using the output ratio of the first detector 1 and the second detector 2. The first detector 1 and the second detector 2 measure in real time the scattered light generated simultaneously at the same location on the test object 4. As described above, the output ratio of the two detection outputs derived from the same generation source 3 and divided into the first and second different wavelengths is kept substantially constant as long as the molecular structure of the test object 4 does not change. The principle works.

On the other hand, if there is a change in the shape of the object 4 to be inspected, for example, a surface waviness or the like, the detection output of the scattered light also changes in accordance with the change in the shape, so that the scattering caused by the surface shape of the object 4 to be inspected. There is a problem that light, that is, noise is mixed in the signal and the measurement accuracy cannot be maintained. That is, the change in the surface shape is detected as noise, even though the change in the molecular structure of the test object 4 is desired to be detected, and this noise must be canceled.

By applying the above-mentioned principle to this problem, the noise mixed in the signal can be canceled. That is, instead of monitoring the absolute value of the detected output value, it is possible to monitor whether or not the output ratio of two detection outputs having different wavelengths from the same place changes with respect to a certain reference. It is possible to know changes in the molecular structure. As a result, it is possible to obtain the effect that quantitative measurement can be performed while canceling the shape information of the test object 4 using the output ratio.

[2] In the present devices 11 to 17 shown in FIGS. 1 to 7, the light having the first wavelength is elastically scattered and the light having the second wavelength is inelastically scattered. Thereby, the present devices 11 to 17 can apply the principle of Raman spectroscopy to the test object 4 to know the change in the molecular structure.

[3] In the present devices 11 and 14 to 17 shown in FIGS. 1 and 4 to 7, a half mirror 6 is further arranged between the test object 4 and the first detector 1. The half mirror 6 receives scattered light and separates it into a transmitted light 7 and a reflected light 8, and light having a first wavelength is obtained from one of the separated light and light having a second wavelength from the other of the separated light. Is obtained. As described above, the first and second detectors 1 and 2 in which the half mirror 6 is interposed between the test object 4 and the test object 4 are scattered lights simultaneously generated at the same location of the test object 4, that is, the same source 3 , And is configured to measure in real time two detection outputs separated into first and second different wavelengths. As a result, highly accurate quantitative measurement while canceling the shape information of the test object 4 using the output ratio is more reliably realized.

[4] The present devices 13 and 14 shown in FIGS. 3 and 4 further include a first optical filter 21 and a second optical filter 22. The first optical filter 21 preferentially transmits light having the first wavelength. The second optical filter 22 preferentially transmits light having the second wavelength. With this, it is possible to easily and surely select the same wavelength as the incident light (Rayleigh scattered light) and the light (Raman scattered light) having a wavelength that is different from the incident light as a very slight component. As a result, highly accurate quantitative measurement based on the Raman effect, in which the frequency of Raman scattered light is the natural frequency of the molecule, is more reliably realized. By providing the first optical filter 21 and the second optical filter 22 in the present devices 15 and 16 shown in FIGS. 5 and 6, the same effect can be obtained.

[5] In the present device 13 shown in FIG. 3, a single detector 10 is used in place of the first detector 1 and the second detector 2. This single detector 10 is provided with a first detection region 23 and a second detection region 24, and is configured to exert the functions of two. The first detection region 23 mainly receives and detects light having the first wavelength that has passed through the first optical filter 21. The second detection region 24 mainly receives and detects light having the second wavelength that has passed through the second optical filter 22. At present, when comparing the price of the detector with that of the optical filter, the detector is much more expensive. If the detector is an expensive one, the device 13 can be provided at a lower cost by using a structure in which one device is used with such a device rather than using two devices per device.

[6] The present apparatus 12 shown in FIG. 2 is configured to include one energy decomposition detector 9 instead of the first detector 1 and the second detector 2. This energy-resolving detector 9 separates dispersed light into light having a first wavelength and light having a second wavelength without using the first and second optical filters 21 and 22 and the half mirror 6. It has a function to measure. Accordingly, the configuration of one device can be further simplified because the first and second optical filters 21 and 22 can be omitted from the present device 13 (FIG. 3) of [5] above. However, the energy-resolving detector 9 that is indispensable to the present device 12 at present is not limited to the first and second detectors 21 and 2 used in the above [1] to [4], but the present device 13 in the above [5]. It is much more expensive than the single detector 10 used in (FIG. 3). Therefore, the present apparatus 12 shown in FIG. 2 has advantages only when it is desired to reduce the size and weight. Further, since the present device 12 can detect the light of the first wavelength and the light of the second wavelength with the same arrangement without positional deviation, the ratio of the two can be accurately obtained, and highly accurate measurement is possible.

[7] In the present device 15 shown in FIG. 5, the first detector 1 may be replaced with the first optical camera 25, and in that case, the second detector 2 is similarly replaced with the second optical camera 26. Composed. Further, an optical lens 18 is arranged on any of the optical paths from the object to be inspected 4 to the first optical camera 25 or the second optical camera 26. These first and second optical cameras 21 and 22 capture the light having the first and second wavelengths and output the respective brightness information. The device 15 performs quantitative measurement while canceling the shape information of the test object 4 using the output ratios of the first and second optical cameras 21 and 22.

The device 15 shown in FIG. 5 is considered to be a modification of the device 16 shown in FIG. 6 and described later. That is, in the present device 16, only one set of the optical lens 18 is arranged between the test object 4 and the half mirror 6 in place of the first and second optical lenses 27 and 28 which were required for two sets. Is. Since the transmitted light 9 and the separated light 8 have different wavelengths, one optical lens 18 also has a different focal length. By considering the arrangement of each part corresponding to it, it is possible to maintain the overall focus even on the optical paths of different wavelengths.

[8] In the present device 16 shown in FIG. 6, the number of the optical lens 18 which is only one in the configuration of the above [7] is increased to two. That is, the first and second optical cameras 25 and 26 are provided with the first and second optical lenses 27 and 28, respectively. The first optical lens 27 is arranged between the first optical camera 25 and the test object 4. Similarly, the second optical lens 28 is arranged between the second optical camera 26 and the test object 4. As described above, the present apparatus 16 in which a dedicated lens is provided for each optical path for each different wavelength can be designed easily and expected to have stable operation, so that a more accurate measurement result can be obtained.

[9] The present device 17 shown in FIG. 7 is provided with a rotating device 29 as a modified example common to the present devices [1] to [7] (FIGS. 1 to 6). The rotating device 29 has a function of changing the relative angle of the test object 4 with respect to the first and second detectors 21 and 22. Thereby, the device 70 can acquire the output ratio of the second detector 2 to the output of the first detector 1 according to the rotation angle of the rotation device 29. It is possible to reconstruct the output ratio thus obtained to generate a cross-sectional image. The thus-obtained cross-sectional image has a high-level diagnostic function similar to a CT scan used in a medical instrument, and it is possible to obtain a more qualified diagnostic result. The same applies to the present device 17 when the first and second optical cameras 21 and 22 are used instead of the first and second detectors 21 and 2.

[10] The present devices 11, 14 to 17 unify the wavelengths of the light having the first wavelength and the light measured by the first detector 1 to be the same. This makes it possible to efficiently obtain highly accurate measurement results.
[11] The devices 11 to 17 preferably employ near infrared rays as the irradiation light 5. As a result, the versatility can be improved, and it can be applied to a wider range of measurement applications. Unless it is necessary to transmit the light to a deep portion, the source 3 can be configured more simply than gamma rays and X-rays, and the risk of exposure and the like can be reduced.

[12] The devices 11 to 17 are configured to measure the object 4 based on the result of clustering the numerical value indicating the ratio between the measured value of light having the first wavelength and the measured value of light having the second wavelength. Changes in the molecular structure within or deep within the are determined. This makes it possible to obtain highly accurate and qualified measurement results.

[13] A nondestructive inspection device (not shown) according to the present invention (hereinafter, also referred to as “present inspection device”) is the scattered light detection device (present device) 11 according to any one of the above [1] to [12]. -17 are used. In the nondestructive inspection device by this, the to-be-inspected object 4 can be applied to the ball bearing, grease, rubber product, resin product, wire, or a mixed product thereof which is in use. It is possible to determine whether or not the license for the continuous use of the test object 4 is acceptable based on the result of analyzing the molecular structure of the test object 4. Further, by applying this nondestructive inspection device to a new product, it can be used for inspection at the time of shipment and detection of initial defects.

In addition, for nondestructive inspection of grease enclosed in ball bearings, fresh one is press-fitted from a small hole at one end of the oil-containing space, and the one in use at that pressure is pushed out from a small hole at the other end for inspection. The extruded object 4 is subjected to nondestructive inspection by being scattered light detected by the present devices 11 to 17 or nondestructively inspected by the present inspection device while being filled in a dedicated transparent case. Can achieve the purpose. It is needless to say that the small hole for taking in and out the grease for the purpose of inspection can be opened and closed and is normally closed during rolling.

As described above, according to the present apparatus and the present inspection apparatus, it is possible to nondestructively inspect the alteration inside the target by using light typified by near infrared rays, for example. In particular, the deterioration of the bearing grease of the elevator and the measurement of the amount of iron powder mixed in the grease, the deterioration of the surface rubber of the urethane handrail and the measurement of cracks in the urethane, the wear deterioration of the anti-vibration rubber and the measurement of rubber hardening, It is possible to measure friction deterioration and rust of frame materials and wires with high accuracy. As a result, it is possible to perform highly accurate inspection and automate the determination of inspection results, shorten the maintenance work time, and improve the quality of maintenance.

INDUSTRIAL APPLICABILITY The present invention may be adopted as a device for determining the bearing itself of an elevator, grease used for the elevator, urethane handrail of an escalator, anti-vibration rubber, frame material, wires, and the degree of deterioration of the coating of electric wires, and the possibility of continuous use There is.

1 First (energy) detector 2 Second (energy) detector 3 (ray/electromagnetic wave) generation source 4 Object (subject)
5 near-infrared 6 half mirror 7 transmitted light 8 reflected light 9 energy decomposition detector 10 (energy) detectors 11 to 17 scattered light detection device (this device)
18 (Optical) Lens 21 First Optical Filter 22 Second Optical Filter 23 First (Energy) Detection Area 24 Second (Energy) Detection Area 25 First (Optical) Camera 26 Second (Optical) Camera 27 First (Optical) ) Lens 28 Second (optical) lens 29 Rotating device

Claims (13)

An electromagnetic wave that belongs to any of gamma rays, X-rays, ultraviolet rays, visible rays, infrared rays, and microwaves is used as irradiation light,
A scattered light detection device for analyzing a molecular structure of the test object based on a result of measuring scattered light from the test object that has received the irradiation light,
A source of the irradiation light,
A first detector disposed in an emission direction that forms an acute angle with respect to the incident direction of the irradiation light with reference to the test object;
A second detector arranged in an emitting direction at an angle different from the acute angle with respect to the incident direction;
Equipped with
Of the scattered light, the light having a first wavelength is measured by the first detector,
Of the scattered light, light having a second wavelength different from the first wavelength is measured by the second detector,
A scattered light detection device for quantitatively measuring while canceling the shape information of the test object by using an output ratio of the first detector and the second detector. The light having the first wavelength is elastically scattered,
The light having the second wavelength is inelastically scattered,
The scattered light detection device according to claim 1. A half mirror is provided between the test object and the first detector,
The half mirror enters the scattered light and separates it into transmitted light and reflected light,
Light having the first wavelength is obtained from the separated one,
Light having the second wavelength is obtained from the other separated light.
The scattered light detection device according to claim 1. A first optical filter that preferentially transmits light having the first wavelength;
A second optical filter that preferentially transmits light having the second wavelength;
With
The scattered light detection device according to claim 1. A single detector is used in place of the first detector and the second detector,
The single detector includes
A first detection region that mainly receives and detects light having the first wavelength that has passed through the first optical filter;
A second detection region for mainly receiving and detecting light having the second wavelength that has passed through the second optical filter;
Is provided,
The scattered light detection device according to claim 4. An energy-resolving detector is provided instead of the first detector and the second detector,
The energy-resolving detector has a function of separately measuring the scattered light into light having the first wavelength and light having the second wavelength.
The scattered light detection device according to claim 1. A first optical camera replacing the first detector;
A second optical camera replacing the second detector;
An optical lens disposed in any of the optical paths from the object to be inspected to the first optical camera or the second optical camera;
Equipped with
Quantitative measurement is performed while canceling the shape information of the object using the output ratio of the first optical camera and the second optical camera.
The scattered light detection device according to claim 1. A first optical lens arranged between the first optical camera and the test object;
A second optical lens disposed between the second optical camera and the test object;
Equipped with
The first optical camera outputs light having the first wavelength through the first optical lens as brightness information,
The second optical camera outputs light having the second wavelength as brightness information through the second optical lens,
The scattered light detection device according to claim 7. A rotating device that changes a relative angle of the test object with respect to the first detector and the second detector;
Acquiring the output ratio of the second detector with respect to the output of the first detector according to the rotation angle of the rotating device,
Reconstructing the acquired output ratio to generate a cross-sectional image,
The scattered light detection device according to claim 1. The wavelength of the light having the first wavelength and the wavelength of the light measured by the first detector are the same,
The scattered light detection device according to claim 1. The irradiation light is near infrared rays,
The scattered light detection device according to claim 1. Based on the result of clustering the numerical value indicating the ratio between the measured value of light having the first wavelength and the measured value of light having the second wavelength,
Determining changes in the molecular structure within or deep within the test object,
The scattered light detection device according to claim 1. The test object is a ball bearing in use, grease, a rubber product, a resin product, a wire, or a mixed product thereof, and the continuation of the test object based on the result of analyzing the molecular structure of the test object. Judge pass/fail of use authorization,
A nondestructive inspection device using the scattered light detection device according to claim 1.

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