JP2007183227A - Electromagnetic wave imaging system, structure fluoroscopy system, and structure fluoroscopy method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out fluoroscopy on a deterioration part generated in a structure at higher precision by avoiding as much as possible the influence of irregular structures existing on the surface of the structure. <P>SOLUTION: An electromagnetic wave imaging system of a millimeter-wave band comprises an image-capturing device for capturing images of the surface of the structure; an analyzer for analyzing the degree of irregularities of the surface of the structure from captured images; a control means for specifying the frequency of electromagnetic waves of millimeter-wave band; an electromagnetic wave generation device for irradiating the structure with the electromagnetic waves of millimeter-wave band; a one-dimensional detector array for detecting the reflected waves of the electromagnetic waves of millimeter-wave band; a distance sensor for measuring a movement distance; a measuring device 2 for evaluating the intensities of the reflected waves detected by the one-dimensional detector array; and a display device 3 for displaying the fluoroscopic image of the structure, by allowing the movement distance measured by the distance sensor associated with the reflected wave intensities evaluated by the measuring device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structure diagnostic technique using electromagnetic waves, and particularly to a technique for nondestructive inspection using electromagnetic waves for deterioration such as cracks and peeling occurring in structures such as concrete.

Concrete that is widely used in the world's buildings often suffers from decay and defects during the manufacturing process and over the years. Such decay and defects are considered to be one of the factors that significantly deteriorate the strength of concrete. For example, if cracks or delamination occur inside a concrete structure, the strength of the structure decreases, and in some cases, there is a risk of inducing the risk of collapse. Examples include collapse of a building due to an earthquake or fall of a tunnel lining concrete block. In order to prevent such an accident, it is necessary to detect an internal crack and peeling of concrete at an early stage.

As a method for detecting internal cracks and peeling of concrete, a method of visually inspecting deterioration of the concrete from the outside can be considered. Further, a non-destructive inspection method that allows the inside of a building to be seen through without destroying the building by using X-ray CT, ultrasonic imaging, microwave imaging, heat distribution imaging, or the like can be considered. Patent Document 1 and Non-Patent Document 2 describe methods for inspecting concrete.
International Publication No. WO00 / 52418 Pamphlet Harayuki Ohara, “Development of 3D imaging radar for concrete slab inspection”, Proceedings of the 7th Underground Electromagnetic Measurement Workshop, 2003

  Actually, the concrete used for a building is actually often covered with wallpaper cloth or paint. In such a case, it is difficult to visually inspect the deterioration of the concrete from the outside.

  In addition, when X-ray CT is used for the non-destructive inspection method, it is difficult to detect the reflected signal from the concrete because of the large X-ray transmission ability, and the X-ray generator and the X-ray detector face each other. It becomes necessary to arrange. Therefore, an apparatus using X-ray CT has a problem that the system scale becomes large. In addition, since X-ray CT is a transmissive imaging method, it is necessary to arrange an X-ray detector behind the concrete surface to be inspected. However, when the concrete to be inspected is a tunnel or an outer wall of a high-rise building, it is difficult to arrange the X-ray detection device behind the concrete surface.

  In addition, ultrasonic imaging is a technique in which ultrasonic waves are incident on a concrete surface in a pulsed manner, and elastic waves propagating in the concrete are detected to detect decay and defects. Therefore, even when ultrasonic imaging is used for the nondestructive inspection method, it is basically desirable that the signal generator and the detector face each other. As a result, there is a problem that the system scale becomes large.

  An imaging apparatus using a microwave is used for exploring a metal pipe or the like embedded in concrete using a radar system, but has a difficulty in spatial resolution. Thermal distribution imaging visualizes the temperature distribution seen from the surface of a building, and utilizes the fact that the heat conduction characteristics differ between a healthy part and a decayed / defected part. However, since the thermal diffusion spreads quickly, there arises a problem that sufficient spatial resolution cannot be obtained for the image.

  Furthermore, early diagnosis of concrete cracks requires accuracy in millimeters as a standard for civil engineering and construction. The size in millimeters is a signal level that is extremely smaller than the wavelength of electromagnetic waves that are generally used for nondestructive inspection of structures, and the characteristics obtained as reflection of electromagnetic waves are also extremely small. Therefore, it is often difficult to detect fine cracks due to an inferior S / N ratio, and in particular, unevenness of coating materials such as wallpaper cloth and paint on the concrete surface is cited as a factor that degrades the S / N ratio. . That is, when the uneven structure on the surface of the covering material is equal to or greater than the wavelength of the electromagnetic wave, it greatly affects the reflected wave, and it is determined whether or not a slight crack is hidden under the covering material. It is difficult. Therefore, there is a risk of overlooking a deteriorated portion lurking in the concrete under the covering material.

  This invention is made | formed in view of the said situation, and the objective of this invention avoids the influence of the uneven structure which exists in the structure surface as much as possible, and sees through the degradation location which arose in the structure with higher precision. There is.

  In order to achieve the above object, a first invention is an electromagnetic wave imaging system in a millimeter wave band, an image imaging device that captures an image of a structure surface, and a degree of unevenness on the structure surface from the captured image. An analysis device for analyzing, a control means for specifying the frequency of millimeter wave electromagnetic waves according to the degree of unevenness analyzed by the analysis device, an electromagnetic wave generator for irradiating a structure with millimeter wave electromagnetic waves, and the millimeter A one-dimensional detector array that detects reflected waves of electromagnetic waves in a wave band, a distance sensor that measures a moving distance, a measuring device that quantifies the intensity of the reflected waves detected by the one-dimensional detector array, and the distance sensor And a display device that displays a perspective image of the structure in which the moving distance measured by the measuring device is associated with the reflected wave intensity quantified by the measuring device, and the electromagnetic wave generating device is specified by the control means. An electromagnetic wave of a millimeter wave band of frequencies, is irradiated to the structure.

  A second invention is a structure fluoroscopy device in an electromagnetic wave imaging system in the millimeter wave band, and an image imaging device that captures an image of a structure surface, and analyzes the degree of unevenness on the structure surface from the captured image An analysis device, a control means for identifying the frequency of millimeter wave electromagnetic waves according to the degree of unevenness analyzed by the analysis device, an electromagnetic wave generator for irradiating a structure with millimeter wave electromagnetic waves, and the millimeter wave A one-dimensional detector array for detecting a reflected wave of the electromagnetic wave in the band and a distance sensor for measuring a moving distance of the structure fluoroscope, wherein the electromagnetic wave generator has a millimeter wave of a frequency specified by the control means The structure is irradiated with a band electromagnetic wave, the one-dimensional detector array transmits the detected reflected wave to a measuring device, and the distance sensor transmits the measured moving distance to a display device.

  A third invention is a structure fluoroscopy method in an electromagnetic wave imaging system in a millimeter wave band, and an image imaging step for capturing an image of a structure surface, and analyzing the degree of unevenness on the structure surface from the captured image An analysis step, a specifying step for specifying the frequency of the electromagnetic wave in the millimeter wave band according to the degree of unevenness analyzed in the analyzing step, and irradiating the structure with the electromagnetic wave in the millimeter wave band of the frequency specified in the specifying step An electromagnetic wave irradiation step, a reflected wave detecting step for detecting a reflected wave of the electromagnetic wave in the millimeter wave band using a one-dimensional detector array, and a measurement for quantifying the intensity of the reflected wave detected by the one-dimensional detector array And a display step for displaying the reflected wave intensity quantified in the measurement step.

  ADVANTAGE OF THE INVENTION According to this invention, the influence of the uneven structure which exists in the structure surface can be avoided as much as possible, and the degradation location which arose in the structure can be seen through with higher precision.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall configuration diagram of an electromagnetic wave imaging system according to an embodiment of the present invention.

The electromagnetic wave imaging system includes a structure surface layer portion fluoroscopy device 1 that sees through a structure using millimeter wave band electromagnetic waves, a lock-in amplifier (measuring instrument) 2, and a control PC (Personal Computer) 3.

  The structure surface layer fluoroscope 1 includes an electromagnetic wave generator 12, an electromagnetic wave detector array 13, a wheel-type distance sensor 14, a frequency switch 15, and an unevenness diagnosis unit 16 in a housing 11. The casing 11 of the structure surface layer fluoroscope 1 is assumed to be a handy casing having a size of about several tens of centimeters square (for example, a total length of about 300 mm) that can be operated with one hand.

  An electromagnetic wave generator (GUNN oscillator, synthesizer, etc.) 12 generates 94-120 GHz band electromagnetic waves (hereinafter referred to as “millimeter waves”). The electromagnetic wave generator 12 diffuses and radiates millimeter waves onto a see-through object such as concrete (hereinafter “target”) using a horn antenna or the like (not shown) attached to the housing 11.

  Note that the frequency of the electromagnetic wave generator 12 of this embodiment can be adjusted by the frequency switch 15. For example, the electromagnetic wave generator 12 outputs an electromagnetic wave having a center frequency of 100 GHz and an electromagnetic wave intensity of 40 mW under the control of the frequency switch 15. The frequency switch 15 adjusts the frequency of the electromagnetic wave generated by the electromagnetic wave generator 12 based on the control signal received from the unevenness diagnosis unit 16.

  The millimeter wave irradiated from the electromagnetic wave generator 12 is irradiated from the opening 19 on the bottom surface of the housing 11 to the target surface. The reflected millimeter wave is detected by the electromagnetic wave detector array 13 installed with the receiving antenna facing the target surface. The electromagnetic wave detector array 13 is a one-dimensional array in which, for example, a planar slot antenna for receiving electromagnetic waves is connected to a plurality of Schottky diodes for detecting the reflection intensity of the electromagnetic waves and arranged in a line. A detector array shall be used. It is assumed that the number of elements of the electromagnetic wave detector array 13 of this embodiment is 16, the distance between the planar slot antennas is every 5 mm, and the sensitivity of the Schottky diode is 100 mV / mW. The electromagnetic wave detector array 13 converts the detected reflected wave intensity into a voltage value by the rectifying action of the diode, and transmits the converted voltage value to the lock-in amplifier 2 as a detection signal.

  The wheel type distance sensor 14 detects the movement distance of the housing 11 and transmits a distance signal (movement distance information) to the control PC 3 via a microcomputer board (not shown). That is, when the housing 11 is scanned by hand, the wheel type distance sensor 14 transmits information on the distance moved by the scanning to the control PC 3. The unevenness diagnosis unit 16 captures an image of the target surface and diagnoses the degree of unevenness based on the captured image. The unevenness diagnosis unit 16 will be described later.

  The lock-in amplifier 2 receives the reflected wave intensity (detection signal) transmitted from the electromagnetic wave detector array 13, digitizes the reflected wave intensity, and outputs it to the control PC 3.

  The control PC 3 receives the reflected wave intensity output from the lock-in amplifier 2 and receives the travel distance information transmitted from the wheel-type distance sensor 14. Then, the control PC 3 draws the reflected wave intensity values detected by the electromagnetic wave detector array 13 according to the moving distance one after another on the output device of the control PC 3. Thereby, the two-dimensional perspective image inside the target surface layer can be displayed (acquired) in real time. The two-dimensional perspective image displayed on the output device of the control PC 3 will be described later.

  Next, the structure surface layer fluoroscope 1 will be described in more detail.

  FIG. 2 is a schematic configuration diagram of the structure surface layer portion fluoroscopic device 1. The structure surface layer fluoroscopic apparatus 1 shown in the figure includes an unevenness diagnosis unit 16, an electromagnetic wave diagnosis unit 17, and a distance sensor unit 18. The unevenness diagnosis unit 16 is installed in front of the electromagnetic wave diagnosis unit 17 with respect to the traveling direction of the structure surface layer fluoroscope 1. Thereby, the uneven structure of the target surface seen through by the electromagnetic wave diagnostic unit 17 can be analyzed in advance, and a frequency suitable for the analyzed uneven structure can be determined.

  That is, the surface of a target such as concrete is often covered with a covering material such as wallpaper cloth or paint. Further, early diagnosis of concrete cracks requires precision in millimeters, and electromagnetic waves with extremely small wavelengths are used to detect the size in millimeters. Therefore, the characteristic obtained as reflection of electromagnetic waves is also a very small signal level. There is no problem if the effect of the coating material on the reflected wave is so small that it can be ignored. However, the uneven structure of the coating material that is the same as or larger than the wavelength of the electromagnetic wave deteriorates the S / N ratio and causes the reflected wave. Has a profound effect on Therefore, it is difficult to determine whether or not there is a slight width crack (deteriorated portion) lurking in the concrete under the covering material, and the crack may be overlooked.

  In general, when the frequency is lowered, the image resolution is lowered and the influence of the uneven structure on the surface is reduced. However, if the resolution is lowered too much, a deteriorated part such as a crack cannot be detected. Therefore, the unevenness diagnosis unit 16 analyzes the uneven structure on the target surface in advance, and specifies the maximum frequency within a range where the uneven structure on the surface does not affect the reflected wave.

  The illustrated unevenness diagnosis unit 16 includes an image capturing device 31, an analysis device 32, a control device 33, and a function table 34. The image capturing device 31 captures an image of the surface of the target using a CCD (Charge Coupled Devices) camera, for example, and sends the captured image to the analyzer 32.

  Then, the analysis device 32 receives the image of the target surface from the image capturing device 31, calculates the edge content in the image using a predetermined edge detection algorithm, and quantifies the degree of unevenness on the target surface. The image edge detection algorithm is described in, for example, the following document.

“Image Analysis Handbook”, Mikio Takagi, Yoshihisa Shimoda, The University of Tokyo Press, p553-556
In the image edge detection algorithm, an edge (contour) is detected by using an image filter such as a Sobel filter.

  In the analysis device 32 of the present embodiment, for example, the number n of edge pixels detected using a Sobel filter is counted. Then, the analyzer 32 calculates the edge content ratio n / m (quantified degree of unevenness of the target surface) by dividing the number of edge pixels n by the number of pixels m of the entire image. Then, the analysis device 32 notifies the control device 33 of the calculated edge content rate.

  When the control device 33 receives the edge content rate notified by the analysis device 32, the control device 33 refers to the function table 34 and specifies the frequency corresponding to the received edge content rate.

  The function table 34 is a table in which the frequency of the electromagnetic wave corresponding to the edge content rate is set for each edge content rate. For example, in the algorithm with the edge coefficient parameter k of the Sobel filter, it is not affected by the maximum k ′ such that the edge content ratio n / m is smaller than a predetermined threshold value a and the surface unevenness that gives the k ′ value. It is assumed that a function of the maximum frequency f of the electromagnetic wave (satisfying a predetermined resolution) is obtained by conducting an experiment in advance. And each edge content rate is thrown into the acquired function, and the frequency corresponding to each edge content rate is calculated, respectively. Then, each edge content rate and the corresponding frequency are stored in the function table 34.

  Note that the function itself may be stored in the function table 34, and when the control device 33 receives the edge content rate, the control unit 33 may calculate the frequency by inputting the received edge content rate into the function. It is assumed that the function table 34 is stored in advance in the memory of the unevenness diagnosis unit 16 or an external storage device (not shown).

  Then, the control device 33 sends a control signal including the specified frequency to the electromagnetic wave diagnostic unit 17. When receiving the frequency signal, the electromagnetic wave diagnostic unit 17 activates the electromagnetic wave diagnostic unit 17 to diagnose the target. When the control device 33 sends a control signal including a frequency to the electromagnetic wave diagnostic unit 17, the controller 33 sounds an electronic sound or the like from a speaker (not shown) to confirm that the unevenness diagnosis is completed. It may be informed to the person.

  The electromagnetic wave diagnostic unit 17 includes a frequency switch 15, an electromagnetic wave generator 12, and an electromagnetic wave detector array 13. The frequency switch 15 receives a control signal from the unevenness diagnosis unit 16. The frequency switcher 15 controls (adjusts) the frequency of the electromagnetic wave generated by the electromagnetic wave generator 12 based on the frequency specified by the control signal.

  The electromagnetic wave generator 12 irradiates the target with electromagnetic waves having a frequency controlled by the frequency switch 15. And the electromagnetic wave detector array 13 permeate | transmits the surface layer inside of a target with a reflected wave, and detects degradation locations, such as the crack which generate | occur | produced in the target. The wheel type distance sensor 14 of the distance sensor unit 18 measures the moving distance of the structure surface layer fluoroscope 1 and transmits it to the control PC 3. The distance sensor unit 18 may measure the moving distance using a distance sensor other than the wheel-type distance sensor 14.

  Next, the case where the concrete crack is imaged using the electromagnetic wave imaging system of this embodiment is demonstrated concretely.

  A crack 82 having a width of 0.2 mm is generated on the concrete surface 81 shown in FIG. And the structure surface layer part fluoroscopic apparatus 1 shall see through concrete in the state which covered the surface layer cover (covering material) 84 on the surface 81 of this concrete. It is assumed that the crack 82 under the surface cover 83 cannot be observed or detected with visible light (visual observation, CCD camera, etc.).

  First, the image capturing device 31 of the unevenness diagnosis unit 16 captures an image of the surface layer cover 83 (imaging region 84).

  FIG. 4 shows image samples of three types of surface layer covers 83 captured by the image capturing device 31. The first surface layer cover shown in FIG. 4 (a) is a coating film used for waterproofing or the like, and has almost no surface unevenness. The second surface layer cover shown in FIG. 4 (b) is a wallpaper having a rough surface of about several hundred paper files on its surface, and has a submillimeter scale uneven structure. The third surface cover shown in FIG. 4C is a wallpaper called “coconut skin finish”, and has unevenness on the surface of several millimeters.

  Then, the analysis device 32 receives the image of the surface layer cover from the image capturing device 31, and detects an edge in the image using an edge detection algorithm.

  FIG. 5 shows the detection results of edges detected by the analysis device 32 using the Sobel filter edge detection algorithm for each image shown in FIG. 5A shows a first surface cover (see FIG. 4A), FIG. 5B shows a second surface cover (see FIG. 4B), and FIG. 5C shows a third surface layer. It is the edge detection result of a cover (refer FIG.4 (c)).

  Note that the edge detection result shown in the figure uses a Sobel filter algorithm implemented in the ImageToolkit of Matlab 7.0, and the edge coefficient parameter k is set to “0.03”. It can be seen at a glance that the third surface cover shown in FIG. 5C has a large edge amount as compared with FIGS. 5A and 5B.

  Then, the analyzer 32 counts the number of edge pixels n from the edge detection result. The number of edge pixels n shown in FIGS. 5A, 5B, and 5C is 0, 145, and 10,261, respectively. Further, the number of pixels m of the entire image shown in the figure is 400 × 200 = 80,000 pixels. The analyzer 32 calculates the edge content ratio n / m (0%, 0.2%, 12.9%) of the image, and quantitatively evaluates the degree of unevenness of the surface layer cover. Then, the analysis device 32 notifies the control device 33 of the calculated edge content rate. The control device 33 refers to the function table 34, identifies a frequency suitable for each edge content rate, and notifies the electromagnetic wave diagnosis unit 17 of the frequency.

  Here, the relationship between the edge coefficient parameter k and the edge content rate will be described.

  FIG. 6 is a plot of the relationship between the edge coefficient parameter k and the edge content n / m for the sample images of the three surface layer covers shown in FIG. Obtained experimentally the relationship between the value of k when the edge content ratio n / m is close to "0" and the electromagnetic wave frequency f that is not affected by the surface irregularities (satisfying the predetermined resolution) In this case, for example, the optimum frequency can be calculated in the situation of the third surface layer cover 63. In the present embodiment, the edge coefficient parameter k is set to “0.03”, and in this case, a function of the electromagnetic wave frequency f that is not affected by surface irregularities is acquired in advance and stored in the function table 34. .

  And the electromagnetic wave diagnostic unit 17 irradiates concrete with the millimeter wave of the frequency notified from the unevenness | corrugation diagnostic unit 16, and sees through concrete. That is, the structure surface layer fluoroscope 1 is scanned on the surface layer cover 83. Thereby, the distance sensor unit 18 transmits movement distance information to the control PC 3. Moreover, the electromagnetic wave diagnostic unit 17 irradiates the millimeter wave of the instructed frequency and detects the reflected wave of the millimeter wave. The reflected wave intensity detected by the electromagnetic wave diagnostic unit 17 is digitized by the lock-in amplifier 2 and displayed as a two-dimensional perspective image on the output device of the control PC 3 in synchronization with the movement distance.

  FIG. 7 is an example of a two-dimensional perspective image when the electromagnetic wave generator 12 of the electromagnetic wave diagnostic unit 17 irradiates the imaging region 84 of FIG. 3 with a 100 GHz band electromagnetic wave having a wavelength of 3 mm. FIG. 7A is a two-dimensional perspective image when the first surface cover (see FIG. 4A) is used. FIG. 7B is a two-dimensional perspective image when the second surface cover (see FIG. 4B) is used. FIG. 7C is a two-dimensional perspective image when the third surface cover (see FIG. 4C) is used. In each illustrated two-dimensional perspective image, the vertical axis indicates the reflection intensity detected for each of the 16 elements of the electromagnetic wave detector array 13, and the horizontal axis indicates the movement distance.

  In the two-dimensional perspective images of the first surface cover and the second surface cover shown in FIGS. 7 (a) and 7 (b), the interior of the concrete surface under the surface layer cover is obtained by irradiating 100GHz band electromagnetic waves with a wavelength of 3mm. It is possible to detect the location of a crack that has occurred. That is, the electromagnetic wave diagnostic unit 17 uses the electromagnetic wave in the 100 GHz band having a wavelength of 3 mm to detect the fine crack 82 in the sub-millimeter unit generated in the concrete through the first surface layer cover and the second surface layer cover. can do.

  On the other hand, in the two-dimensional fluoroscopic image of the third surface layer cover (wallpaper finished with wallpaper) shown in FIG. 7 (c), when the 3mm 100GHz band electromagnetic wave is irradiated, the unevenness of the surface layer cover greatly reflects the electromagnetic wave. It is not possible to judge (detect) the location of the crack that has occurred inside the concrete surface under the surface cover. In order to avoid the output of the two-dimensional perspective image as shown in FIG. 7C, the unevenness diagnosis unit determines and determines the maximum frequency while eliminating the influence of the uneven structure by lowering the frequency. The frequency is sent to the electromagnetic wave diagnostic unit 17.

  According to this embodiment, the influence of the concavo-convex structure existing on the surface of the structure can be avoided as much as possible, and a deteriorated portion generated in the structure can be seen through with higher accuracy. That is, in this embodiment, an edge is detected from an image of the structure surface to determine the degree of unevenness, a frequency corresponding to the degree of unevenness is selected, and an electromagnetic wave with the frequency is irradiated onto the structure. As a result, it is possible to obtain a structure perspective image in which the influence of the concavo-convex structure is suppressed while maintaining a constant image resolution.

  Further, in the present embodiment, by using millimeter wave band electromagnetic waves, it is possible to detect cracks in the fine structure surface layer of millimeter width that cannot be detected by microwave radar or infrared rays. Moreover, in this embodiment, by using a millimeter wave band electromagnetic wave to see through the structure, it is possible to detect a deteriorated portion such as a crack generated in the structure without destroying the structure.

  Moreover, since the electromagnetic wave diagnostic unit 17 of the structure surface layer fluoroscopic device 1 of the present embodiment is a reflection type detection using an electromagnetic wave in the millimeter wave band, a detector is installed on the back side of the target like an X-ray CT. There is no need to do. Thereby, a simple system configuration (miniaturization of the apparatus) is possible, and the application area (field) of the structure to be seen through can be expanded.

  In addition, the structure surface layer fluoroscopic device 1 of the present embodiment is a handy type device that can be operated with one hand, and thus is excellent in portability on site and has good operability.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary. For example, in this embodiment, the analysis device 32, the control device 33, and the function table 34 that analyze the degree of unevenness on the surface of the structure and determine the frequency of the electromagnetic wave are included in the unevenness diagnosis unit 16 of the structure surface layer fluoroscopic device 1. It is installed. However, the present invention is not limited to this, and these devices 32, 33, 34 may be mounted on the control PC 3. In this case, the image capturing device 31 of the structure surface layer fluoroscopic device 1 transmits the captured image to the control PC 3. Then, the control PC 3 analyzes the transmitted image, identifies a frequency suitable for the image, and transmits the identified frequency to the frequency switch 15 of the structure surface layer fluoroscopic device 1.

1 is an overall configuration diagram of an electromagnetic wave imaging system according to an embodiment of the present invention. It is a schematic structure figure of a structure surface covering part fluoroscope. It is a figure which shows an example of a concrete crack. It is a figure which shows the image sample of a surface layer cover. It is a figure which shows an edge detection result. It is a figure which shows the relationship between an edge coefficient parameter and edge content rate. It is a figure which shows the 2-dimensional perspective image example of a concrete crack.

Explanation of symbols

1 Structure surface layer see-through device 2 Lock-in amplifier 3 Control PC
DESCRIPTION OF SYMBOLS 11 Case 12 Electromagnetic wave generator 13 Electromagnetic wave detector array 14 Wheel type distance sensor 15 Frequency switch 16 Concavity and convexity diagnostic unit 17 Electromagnetic wave diagnostic unit 18 Distance sensor unit 31 Image pick-up device 32 Analyzing device 33 Control device 34 Function table

Claims (5)

A millimeter wave electromagnetic wave imaging system,
An image capturing device for capturing an image of the surface of the structure;
An analyzer for analyzing the degree of unevenness on the surface of the structure from the captured image;
Control means for identifying the frequency of electromagnetic waves in the millimeter wave band according to the degree of unevenness analyzed by the analyzer,
An electromagnetic wave generator for irradiating a structure with electromagnetic waves in the millimeter wave band;
A one-dimensional detector array for detecting a reflected wave of the electromagnetic wave in the millimeter wave band;
A distance sensor for measuring the travel distance;
A measuring device for digitizing the intensity of the reflected wave detected by the one-dimensional detector array;
A display device that displays a perspective image of a structure in which the moving distance measured by the distance sensor and the reflected wave intensity quantified by the measuring device are associated with each other;
The electromagnetic wave imaging system, wherein the electromagnetic wave generator irradiates a structure with an electromagnetic wave in a millimeter wave band having a frequency specified by the control means. The electromagnetic wave imaging system according to claim 1,
A storage device in which the degree of unevenness on the surface of the structure and the frequency corresponding to the degree of unevenness are set;
The electromagnetic wave imaging system characterized in that the control means specifies the frequency of electromagnetic waves in a millimeter wave band corresponding to the degree of unevenness analyzed by the analysis device with reference to the storage device. The electromagnetic wave imaging system according to claim 1,
The image pickup device, the electromagnetic wave generator, the one-dimensional detector array, and the distance sensor are mounted on a handy-type housing,
The electromagnetic imaging system, wherein the imaging device is installed in front of the casing in the traveling direction. A structure fluoroscopy device in a millimeter wave electromagnetic wave imaging system,
An image capturing device for capturing an image of the surface of the structure;
An analyzer for analyzing the degree of unevenness on the surface of the structure from the captured image;
Control means for identifying the frequency of electromagnetic waves in the millimeter wave band according to the degree of unevenness analyzed by the analyzer,
An electromagnetic wave generator for irradiating the structure with millimeter wave electromagnetic waves;
A one-dimensional detector array for detecting a reflected wave of the electromagnetic wave in the millimeter wave band;
A distance sensor for measuring the moving distance of the structure fluoroscopic device,
The electromagnetic wave generator irradiates a structure with an electromagnetic wave of a millimeter wave band having a frequency specified by the control means,
The one-dimensional detector array transmits the detected reflected wave to a measuring device,
The distance sensor transmits the measured moving distance to a display device. A structure perspective method in an electromagnetic wave imaging system in the millimeter wave band,
An image capturing step for capturing an image of the surface of the structure;
An analysis step of analyzing the degree of unevenness on the surface of the structure from the captured image;
A specific step of identifying the frequency of the electromagnetic wave in the millimeter wave band according to the degree of unevenness analyzed in the analysis step;
An electromagnetic wave irradiation step of irradiating a structure with an electromagnetic wave in the millimeter wave band having a frequency specified in the specific step;
A reflected wave detecting step of detecting a reflected wave of the electromagnetic wave in the millimeter wave band using a one-dimensional detector array;
A measurement step for quantifying the intensity of the reflected wave detected by the one-dimensional detector array;
And a display step for displaying the reflected wave intensity quantified in the measurement step.
Structure see-through method characterized by the above.