JP6975675B2 - Mobile scanner - Google Patents

Description

The present invention relates to a mobile scanner that scans to inspect the inside of a moving object as an inspection target.

As a scanner for inspecting the inside of an inspection target, for example, a body scanner for performing a body check at an airport or the like is known (see, for example, Patent Document 1).

However, in the above-mentioned Patent Document 1, it is premised that the subject is confined in the space and the inspection is performed in a state of being immobile, and a large number of people such as a ticket gate of a station or an event venue are sequentially checked. Is considered unsuitable, for example, there is a request to realize a walk-through body scanner with a passage type.

Japanese Unexamined Patent Publication No. 2015-36680

The present invention has been made in view of the above points, and an object of the present invention is to provide a moving object scanner capable of inspecting a moving object such as a pedestrian, that is, a moving object.

In order to achieve the above object, the mobile scanner according to the present invention transmits a terahertz wave in a predetermined wavelength band toward the moving object to be inspected, receives the terahertz wave reflected from the moving object, and transmits the terahertz wave to the moving object. It is equipped with an inspection unit that scans, a position detection unit that detects the position of the moving object, and a direction switching mirror that switches the propagation direction of the terahertz wave from the inspection unit according to the position of the moving object detected by the position detection unit. ..

By using the terahertz wave in the mobile scanner, it is possible to acquire a scanned image having a necessary resolution even when the inspection target moves. At this time, in particular, since the position of the moving object can be detected by the position detection unit and the propagation direction of the terahertz wave can be adjusted by the direction switching mirror accordingly, it is possible to secure a state in which the terahertz wave is appropriately irradiated to the inspection target. .. For example, for a pedestrian as a moving object, the direction of the direction switching mirror is switched according to the movement of one pedestrian to scan from multiple directions, and many pedestrians such as station ticket gates and event venues Appropriate body check can be performed by switching the direction of the direction switching mirror so that the inspection unit can scan in parallel in the case of sequentially approaching.

In a specific aspect of the present invention, the inspection unit scans the moving object from different directions by switching with the direction switching mirror. In this case, since the moving object to be inspected can be scanned from different angles, it can be applied to, for example, a body check in which a person is inspected from various directions.

In another aspect of the present invention, the direction switching mirror switches the direction so as to scan a plurality of moving objects simultaneously existing in a scannable range in parallel. In this case, it becomes possible to deal with a plurality of moving objects.

In yet another aspect of the present invention, a plurality of position detecting units are provided along the moving direction of the moving body. In this case, scanning can be performed while detecting the position of the moving body based on the detection results of the position detection units provided at different positions.

In yet another aspect of the present invention, the direction switching mirror is fixed in a posture determined for each moving object detection by the plurality of position detection units. In this case, the moving object can be scanned from a different direction for each predetermined position.

Yet another aspect of the present invention is a body scanner that targets a pedestrian as a moving object, the inspection unit scans a part of the human body, and the position detection unit detects a pedestrian. Is. In this case, a body scan targeting a pedestrian, that is, a body scan without stopping a person can be performed.

In yet another aspect of the present invention, there is provided an image creating unit that creates image data for each switching by the direction switching mirror based on the scanning result of the moving object by the inspection unit. In this case, an image based on data obtained by scanning a moving object from a plurality of directions is created.

Yet another aspect of the present invention comprises a passage housing that forms a passage that defines the direction of movement of the moving body and arranges a position detector along the passage, with a direction switching mirror provided on the side of the passage. , Irradiate a terahertz wave toward a moving body moving along a passage. In this case, for example, scanning can be reliably performed by passing a moving body in a passage defined by a passage housing constituting a ticket gate of a station or the like.

It is a top view which conceptually shows one configuration example of the mobile scanner of 1st Embodiment. It is a conceptual diagram for demonstrating an example about a direction change mirror. It is a conceptual diagram for demonstrating an example about an inspection part. (A) and (B) are conceptual plan views for explaining how to scan a pedestrian who is a moving body from one direction. It is a top view which conceptually shows the state of scanning a pedestrian from a first direction. It is a top view which conceptually shows the state of scanning a pedestrian from a second direction. It is a top view which conceptually shows the state of scanning a pedestrian from a third direction. It is a top view which conceptually shows an example of the operation of the mobile scanner of 2nd Embodiment. It is a flowchart which shows an example of various processing of a mobile scanner.

[First Embodiment]
Hereinafter, an outline of an example of the mobile scanner according to the first embodiment will be described with reference to the drawings.

The mobile scanner 100 according to one embodiment of the present embodiment includes an inspection unit 10 that transmits a terahertz wave as a measurement wave, a direction switching mirror 20 that switches the propagation direction of the terahertz wave from the inspection unit 10, and a movement as an inspection target. It includes a position detection unit 30 that detects the position of the body, a control unit 50 that controls the operation of each unit, and an image creation unit 60 that creates an image based on information about a scan result from the control unit 50. Here, as an example, the mobile scanner 100 is a body scanner in which a pedestrian PE passing through a specific passage such as a ticket gate of a station is a moving body to be inspected. Further, in one example here, more specifically, at least a part of the above-mentioned parts constituting the mobile scanner 100 is provided in a passage housing CA composed of a ticket gate or the like provided at a ticket gate of a station. It is assumed that there is. That is, the passage housing CA, which is a ticket gate or the like, defines the moving direction (traveling direction) of the pedestrian PE by forming the passage PT of the pedestrian (moving body) PE to be inspected, and detects the position. Each part such as part 30 is installed. Correspondingly, the mobile scanner 100 can scan in the passage PT. In other words, the mobile scanner 100 scans from the entrance to the exit of the passage PT as a target range. In the above, the ticket gate mentioned as the passage housing CA is an example, and in addition to this, the passage housing CA in which the direction switching mirror 20 and the like can be installed in various places such as the entrance / exit gate of the event venue and the passage passage. can do.

Further, here, as shown in the figure, the traveling direction of the pedestrian PE to be inspected indicated by the arrow D1 is the + Z direction, and in the plane perpendicular to the Z direction, the vertical direction, that is, the vertical direction is the Y direction, and the Z direction and The horizontal direction, which is a direction orthogonal to both of the Y directions, is defined as the X direction.

Hereinafter, each part constituting the mobile scanner 100 will be described. First, of the mobile scanner 100, the inspection unit 10 transmits the terahertz wave TW in a predetermined wavelength band toward the pedestrian PE, which is a moving object to be inspected, and the terahertz wave TW reflected from the pedestrian PE. The reflection component RW is received and the pedestrian PE is scanned. That is, the inspection unit 10 scans a part of the human body. In the illustrated example, the inspection unit 10 is installed on the + X side of the passage housing CAs arranged in a pair in the X direction in order to form the passage PT, and the terahertz wave TW toward the −X side, that is, the passage PT side. Is being sent. An example of the internal structure of the inspection unit 10 will be described later with reference to FIG.

As shown in the figure, the direction switching mirror 20 is provided on the side of the passage PT so as to face the transmitting side (-X side) of the inspection unit 10, and the terahertz wave TW from the inspection unit 10 is directed to the passage PT side. The direction of reflection is adjusted, and the terahertz wave TW is irradiated toward the pedestrian PE moving in the Z direction along the passage PT. On the contrary, of the terahertz wave TW, the reflected component RW reflected by the pedestrian PE is irradiated toward the inspection unit 10.

In the illustrated example, the inspection unit 10 and the direction switching mirror 20 are arranged on the + X side of the side of the passage PT (on the left side when facing the traveling direction for pedestrians), but this is how to arrange them. Not limited to.

Further, as illustrated in FIG. 2, the direction switching mirror 20 is a plate-shaped member extending in the Y direction, that is, in the vertical direction, and is driven by the rotation driving unit 21 to rotate the central axis AX extending in the Y direction. As, it is rotatable. In the mobile scanner 100 shown in FIG. 1 and the like, the direction switching mirror 20 rotates around the Y axis under the control of the control unit 50, so that the propagation direction of the terahertz wave TW from the inspection unit 10 is switched and is an inspection target. It is possible to scan the pedestrian PE from multiple directions.

Returning to FIG. 1, the position detection unit 30 is composed of a motion sensor that detects a pedestrian PE. In the illustrated example, a plurality of sets of motion sensors are arranged to form the position detection unit 30 along the passage PT forming the moving direction of the moving body, that is, the traveling direction of the pedestrian PE. Various motion sensors can be used, but here, as an example, a set of infrared light sensors 30A and 30B for transmitting and receiving infrared light is used in the direction in which the infrared light IL crosses the passage PT. Install so that it is ejected (typically in the X direction). That is, the infrared light sensors 30A and 30B detect that the infrared light IL is blocked (shielded) when the pedestrian PE passes, thereby detecting the position of the moving pedestrian PE. In the illustrated example, two sets of infrared light sensors 30A are used to detect the positions of the first sensor unit 31 provided on the entrance side of the passage PT and the second sensor unit 32 provided on the exit side. , 30B shall be provided. However, the present invention is not limited to this example, and the position detection unit 30 may perform position detection in more detail by, for example, arranging more sensors along the passage PT.

The control unit 50 is composed of, for example, various control circuits and is connected to each unit constituting the mobile scanner 100 as described above, controls the operation of these units, and has an inspection acquired by scanning by the inspection unit 10. The resulting data is transmitted to the image creation unit 60.

The image creation unit 60 is composed of, for example, a PC having a display monitor or the like and a CPU, a GPU or the like for enabling various information processing, and various image processing regarding the scan result transmitted from the control unit 50. The analysis result of the data acquired by scanning on the display monitor is visualized and shown.

Hereinafter, one configuration example of the above-mentioned inspection unit 10 will be described in detail with reference to FIG. The inspection unit 10 illustrated in the figure is composed of a transmission unit Tx that transmits a terahertz wave TW, a reception unit Rx that receives a reflection component RW reflected by the inspection target, a half mirror, and the like, and transmits and transmits the terahertz wave TW. It includes a beam splitter BS that performs reflection, a galvano mirror GM as a scan type mirror, and a lens LS that transmits scan light from the galvano mirror GM to the outside of the device. The terahertz wave TW is transmitted from the lens LS while condensing it toward the pedestrian PE to be inspected.

Of these, first, the transmitting unit Tx is an electromagnetic wave transmitting device that transmits a terahertz wave TW having a predetermined wavelength band, for example, a wavelength band having a frequency of 0.1 to 2 THz, that is, a wavelength band of 150 to 3000 μm. The direction of the terahertz wave TW is centered on the traveling direction as the optical axis of the inspection unit 10.

Further, the receiving unit Rx is an electromagnetic wave receiving device or an electromagnetic wave measuring device capable of receiving a component in the wavelength band of the terahertz wave TW. The receiving unit Rx receives the reflected component RW reflected by the detection target (pedestrian PE in each example) in the terahertz wave TW. In the figure, one receiving unit Rx is used, but it is also possible to configure the receiving side with a plurality of receiving units, or to include a plurality of light receiving elements in one receiving unit Rx. be. By setting the number to a plurality, the change state of the reflection component RW can be grasped more accurately.

Further, the beam splitter BS is composed of, for example, a half mirror, and the transmission reflection surface formed by the half mirror is arranged so as to be tilted by 45 ° with respect to the optical axis of the transmitting portion Tx. The receiving unit Rx is arranged at a position symmetrical to the transmitting unit Tx with respect to the beam splitter BS, and the component of the reflected component RW is acquired by receiving the component of the return light reflected by the beam splitter BS. ..

Further, the galvano mirror GM is arranged on the optical axis at a certain distance from the transmitting portion Tx, and rotates (swings) by one axis about an axis orthogonal to the optical axis, for example. That is, scanning in the uniaxial direction of the terahertz wave TW is performed. The scanning direction can be variously set depending on the arrangement of the optical system, but here, scanning is performed in the vertical direction perpendicular to the traveling direction (Z direction) shown in FIG. 1 and the like, that is, in the Y direction. That is, scanning is performed along the direction switching mirror 20 whose longitudinal direction is the Y direction shown in FIG.

The lens LS is arranged toward the outside of the device, that is, toward the reflecting surface of the direction switching mirror 20 in order to emit the scanning light from the galvano mirror GM.

As described above, the mobile scanner 100 of the present embodiment has a line scan type configuration by performing irradiation with the direction switching mirror 20 while primary scanning the terahertz wave TW in the Y direction in the inspection unit 10. ing.

Here, regarding scanning to the human body using a scanner, among the cases where it is used at a place such as a ticket gate of a station or an event venue, especially when a large number of people are to be sequentially body-checked, the space is as in the past. It is considered that the method of confining the subject and performing the inspection in a state where the person does not move is considered to be unsuitable, and a walk-through body scanner with a passage type is desired. In this case, in order to realize a walk-through body scanner with a passage type, it may be necessary to inspect the front and back of the body from an oblique direction, for example. In addition, it is also necessary to be able to analyze moving inspection targets while maintaining a resolution sufficient for inspection. On the other hand, in the mobile scanner 100 of the present embodiment, as described above, by using the component in the wavelength band of the terahertz wave TW, even if the inspection target moves like a pedestrian. Image data is acquired while maintaining sufficient resolution, and terahertz wave TW is irradiated from different directions according to movement by a direction switching mirror 20 or the like to check the pedestrian PE to be inspected from various directions. It is possible.

Hereinafter, returning to FIG. 1, the outline of a series of operations by each part constituting the mobile scanner 100 described above will be described. First, as shown in the figure, when the pedestrian PE is detected by shading the infrared light IL in the first sensor unit 31 provided on the entrance side of the passage PT, the first sensor unit 31 notifies that effect. Notify the control unit 50. Upon receiving the notification, the control unit 50 operates the inspection unit 10 and the direction switching mirror 20 so as to irradiate the terahertz wave TW toward the first sensor unit 31 side where the pedestrian PE is present. That is, the control unit 50 rotates the direction switching mirror 20 around the Y axis so that the reflective surface of the direction switching mirror 20 is slightly tilted so as to face the entrance side of the passage PT. By transmitting the terahertz wave TW from the inspection unit 10, the propagation direction of the terahertz wave TW from the inspection unit 10 is the direction of the pedestrian PE in the vicinity of the first sensor unit 31 (first direction DR1). Switch to.

Here, while the pedestrian PE is detected by the first sensor unit 31, the direction switching mirror 20 is fixed in a predetermined posture, that is, the first direction DR1 does not change. It has become. On the other hand, the pedestrian PE continues to move in the traveling direction (+ Z direction) indicated by the arrow D1. As a result, each part of the pedestrian PE is scanned.

To explain the above in more detail with reference to FIG. 4, first, as illustrated in FIG. 4 (A), at the stage when the pedestrian PE begins to be detected in the first sensor unit 31, the terahertz wave TW is generated. Of the front surface of the pedestrian PE, the reflection is performed on the side (−X side) far from the direction switching mirror 20 in the X direction. That is, the reflection position RP of the terahertz wave TW is relatively on the −X side.

On the other hand, when the pedestrian PE advances in the traveling direction (+ Z direction) indicated by the arrow D1, as shown in FIG. 4 (B), the reflection position RP of the terahertz wave TW gradually switches the direction as it advances. It will shift to the side relatively close to the mirror 20 (+ X side). Therefore, while the pedestrian PE is detected by the first sensor unit 31, the scan image of the pedestrian PE can be obtained by continuing the detection with the direction switching mirror 20 fixed in a predetermined posture. .. In this case, the scan is mainly performed on the front side of the pedestrian PE. Further, at this time, for example, the inspection unit 10 may adjust the focal position or the like, if necessary.

Hereinafter, the details of the scanning operation by the mobile scanner 100 performed when the pedestrian PE passes from the entrance to the exit of the passage PT will be described with reference to FIGS. 5 to 7. In the example here, three sets of infrared light sensors 30A and 30B are used as the position detection unit 30 in order to detect the position along the passage PT at three locations on the entrance side, the vicinity of the center, and the exit side of the passage PT. It shall be provided. That is, the position detection unit 30 includes first to third sensor units 31 to 33 composed of infrared light sensors 30A and 30B, respectively, and these are connected to the control unit 50 to control the operation. And.

FIG. 5 is a plan view conceptually showing how the mobile scanner 100 of the above aspect scans the pedestrian PE from the first direction DR1, and is an example of an aspect of inspecting the front surface of the pedestrian PE. Shows. More specifically, FIG. 5 shows infrared rays in the first sensor unit 31 arranged on the most −Z side in the traveling direction, that is, on the entrance side of the passage PT, among the first to third sensor units 31 to 33. The state of the operation when the pedestrian PE is detected based on the blockage detection of the optical IL1 is shown. In this case, the first direction DR1 is a direction having a component on the −Z side with respect to the lateral direction (−X direction).

In this case, as described above, the control unit 50 rotates the direction switching mirror 20 around the Y axis, and the reflection surface of the direction switching mirror 20 faces the entrance side of the passage PT. The terahertz wave TW is transmitted from the inspection unit 10 after being arranged at an angle toward the inspection unit 10, that is, after being fixed in a predetermined posture. As a result, the terahertz wave TW is irradiated toward the first direction DR1, and the front side of the pedestrian PE is scanned as the pedestrian PE moves. In this case, for example, as shown in the figure, when the pedestrian PE has a knife KN or the like on the chest, the image creation unit 60 analyzes the inspection result regarding the detection of the reflection component RW by the inspection unit 10. By doing so, for example, in the display unit DS of the image creation unit 60, it is possible to display the analyzed image together with the display indicating that there is a foreign substance on the front surface of the pedestrian PE. As the processing related to the above scan result, for example, the result of scanning the front side of the pedestrian PE is integrated with respect to time, that is, with respect to the moving distance of the pedestrian PE, so that the situation of the front portion of the pedestrian PE is imaged. can do. Further, by determining the presence or absence of foreign matter from the imaged data, the above visualization becomes possible.

FIG. 6 is a plan view conceptually showing how the mobile scanner 100 of the above aspect scans the pedestrian PE from the second direction DR2, and is an example of an aspect of inspecting the side surface of the pedestrian PE. Shows. More specifically, FIG. 6 shows the infrared light IL2 in the second sensor unit 32 arranged at an intermediate position in the traveling direction, that is, near the center of the passage PT, among the first to third sensor units 31 to 33. It shows the state of the operation when the pedestrian PE is detected based on the blockage detection of. In this case, the second direction DR2 is a direction having components in a substantially reference direction with respect to the lateral direction (−X direction).

In this case, the control unit 50 rotates the direction switching mirror 20 around the Y axis and arranges the direction switching mirror 20 to be sideways or almost sideways so that the terahertz wave TW is not reflected from the inspection unit 10 on the reflecting surface. The terahertz wave TW is transmitted from the inspection unit 10 after being in a state, that is, in a state where it is fixed in a predetermined posture. As a result, the terahertz wave TW is irradiated toward the second direction DR2, and the side surface side of the pedestrian PE (in the figure, the left side surface side of the pedestrian PE) is scanned along with the movement of the pedestrian PE. In this case, for example, when the pedestrian PE does not have anything on the side surface, the display unit DS of the image creation unit 60 is the result of image analysis of the scan result by the inspection unit 10 by the image creation unit 60. In, it is possible to display that there is no foreign matter on the side surface of the pedestrian PE and that the inspection has been completed successfully, and that the analyzed image is not particularly displayed.

FIG. 7 is a plan view conceptually showing how the mobile scanner 100 of the above aspect scans the pedestrian PE from the third direction DR3, and is an example of an aspect of inspecting the back surface of the pedestrian PE. Shows. More specifically, FIG. 7 shows infrared light in the third sensor unit 33 arranged on the most + Z side in the traveling direction, that is, on the exit side of the passage PT, among the first to third sensor units 31 to 33. The state of the operation when the pedestrian PE is detected based on the interruption detection of IL3 is shown. In this case, the third direction DR3 is a direction having a component on the + Z side with respect to the lateral direction (−X direction).

In this case, the control unit 50 rotates the direction switching mirror 20 around the Y axis and tilts the reflection surface of the direction switching mirror 20 slightly toward the inspection unit 10 side from the state just beside the exit side of the passage PT. The terahertz wave TW is transmitted from the inspection unit 10 after being placed in a state of being arranged, that is, in a state of being fixed in a predetermined posture. As a result, the terahertz wave TW is irradiated toward the third direction DR3, and the back side of the pedestrian PE is scanned as the pedestrian PE moves. In this case, for example, when the pedestrian PE does not have anything on the back surface, the display unit DS of the image creation unit 60 is the result of image analysis of the scan result by the inspection unit 10 by the image creation unit 60. In, it is possible to display that there is no foreign matter on the side surface of the pedestrian PE and that the inspection has been completed successfully, and that the analyzed image is not particularly displayed.

In the above example described above, the directions regarding the first to third directions DR1 to DR3, which are the three different propagation directions, depending on the first to third sensor units 31 to 33 arranged at the three different positions, respectively. By switching the posture of the switching mirror 20, the front surface, the side surface, and the back surface of the pedestrian PE can be scanned.

As described above, in the mobile scanner 100 according to the present embodiment, by using the terahertz wave TW, even when the inspection target moves, for example, a pedestrian PE or the like, the scanning with a necessary resolution is sufficient. Images can be acquired. At this time, in particular, since the position detection unit 30 can detect the position of the moving pedestrian PE and the direction switching mirror 20 can adjust the propagation direction of the terahertz wave TW accordingly, an appropriate terahertz for the pedestrian PE can be adjusted. The irradiation state of the wave TW can be secured. Further, in the case of the present embodiment, for example, the direction of the direction switching mirror 20 can be switched and scanned from a plurality of directions according to the movement of the pedestrian PE, that is, the change in the position.

Further, in the above case, the position of the pedestrian PE to be inspected is detected by using the position detection unit 30 composed of a motion sensor or the like, and terahertz only in the direction in which the pedestrian PE detected by the direction switching mirror 20 is present. It is configured to radiate wave TW. That is, by using the position detection unit 30 and the direction switching mirror 20, one inspection unit 10 realizes detection in two or more directions. This makes it possible to reduce the number of inspection units 10 and reduce costs. In general, a set of a transmitting device that emits a terahertz wave and a set of a receiving sensor that receives a terahertz wave are expensive. Can be expensive.

[Second Embodiment]
Hereinafter, an example of the mobile scanner according to the second embodiment according to the present invention will be outlined with reference to FIG. 8 and the like. The mobile scanner 200 according to the present embodiment is a modification of the mobile scanner 100 of the first embodiment, and performs processing corresponding to the case where a plurality of pedestrian PEs are simultaneously present in a scannable range. Since the same is true except for the above, the same reference numerals are given to common components for the entire configuration, and detailed description thereof will be omitted.

Also in the mobile scanner 200 of the present embodiment, as in the case of the mobile scanner 100 of the first embodiment, the pedestrian PE is moved, that is, the direction of the direction switching mirror 20 is switched according to the change of the position. The scan is performed from the direction of.

Here, in the first embodiment, the scan is described for a pedestrian who is one mobile body, but more generally, depending on the installation environment of the mobile body scanner, a plurality of moving bodies are simultaneously present in the scannable range. There is a possibility. The mobile scanner 200 as one aspect of the present embodiment is an example of one having a processing function assuming such a case. For this reason, the mobile scanner 200 of the present embodiment is a periodic scan for causing the direction switching mirror 20 to periodically and alternately scan a plurality of mobile objects in the control unit 250 that controls each unit. It further includes a control unit 250A. That is, the periodic scan control unit 250A switches the direction of the direction switching mirror 20 so that a plurality of moving objects existing in the passage PT at the same time are scanned in parallel.

Further, here, as shown as an example in FIG. 8, it is assumed that two pedestrian PEs exist at the same time in the passage PT which is a scannable range by the mobile scanner 200. More specifically, it is assumed that when the first pedestrian PE1 approaches the exit of the passage PT, the second pedestrian PE2 newly enters the passage PT. That is, the pedestrian PE1 is detected based on the blocking detection of the infrared light IL3 in the third sensor unit 33, and the pedestrian PE2 is detected based on the blocking detection of the infrared light IL1 in the first sensor unit 31. By notifying the control unit 250, the control unit 250 recognizes that there are two pedestrians PE1 and PE2 in front and behind at the same time. In this case, the periodic scan control unit 250A of the control unit 250 directs the terahertz wave TW to the third direction DR3 and the first direction DR1 at a predetermined fixed period, and scans both directions. The switching operation of the switching mirror 20 is performed. That is, in the above case, the mobile scanner 200 is capable of simultaneous detection in two directions by alternately scanning at regular intervals with the direction switching mirror 20. The interval of a fixed cycle is appropriately determined according to the scanning performance of the mobile scanner 200, the walking speed assumed for the pedestrian PE, and the like.

Hereinafter, an example of various processes of the mobile scanner 200 will be described with reference to the flowchart of FIG. When the mobile scanner 200 is activated, the control unit 250 first confirms whether the pedestrian PE, which is a mobile body, is detected by the position detection unit 30 composed of a motion sensor or the like. More specifically, here, for example, at a plurality of locations (two or more locations) such as whether or not detection is performed by the sensor units 31, 33, etc., which are motion sensors, on both the entrance side and the exit side. Whether or not to detect is performed (step S101). That is, as in the case of FIG. 8, it is detected whether or not two pedestrians PE1 and PE2 are present at the same time.

If it is determined in step S101 that the detection is not performed at a plurality of locations (step S101: no), the control unit 250 further determines whether or not to detect at a single location (one location) in the position detection unit 30 (step). S102). That is, it detects whether or not even one pedestrian PE exists. In step S102, when it is confirmed that the target exists, that is, one pedestrian PE exists in the passage PT within the detection range (step S102: yes), the control unit 250 refers to the detected target. Start scanning operation. That is, as various operations described in the first embodiment, first, the direction switching mirror 20 is switched in order to direct the terahertz wave TW in the direction in which the pedestrian PE exists, and the posture of the direction switching mirror 20 is changed in that direction. It is fixed (step S103), line scan measurement using the terahertz wave TW is performed by the inspection unit 10 (step S104), and while the pedestrian PE is detected at one place in step S102 (step S101: no and). Step S102: yes), the above operation is repeated.

On the other hand, if it is determined in step S101 that the detection is detected at a plurality of locations (step S101: yes), the control unit 250 periodically cycles the direction switching mirror 20 under the control of the periodic scan control unit 250A as described above. While performing the scanning operation (step S105), the line scan measurement using the terahertz wave TW is performed by the inspection unit 10 (step S104), and while the pedestrian PE is detected at a plurality of points in step S101 (step S101). : Yes), the above operation is repeated. That is, in this case, pedestrian PEs detected at two or more locations are simultaneously detected.

If it is determined in step S102 that the pedestrian PE has not been detected (step S101: no), the control unit 250 determines that there is no pedestrian PE in the passage PT, and performs a series of operations. To finish. Even in this case, for example, while the drive power of the mobile scanner 200 is turned on, the series of operations from step S101 may be repeated again.

As described above, also in the present embodiment, by using the terahertz wave TW in the mobile scanner 200, it is possible to acquire a scanned image having a necessary resolution for a moving inspection target such as a pedestrian PE. It is possible to secure an appropriate terahertz wave TW irradiation state for the pedestrian PE. Further, in the case of the present embodiment, for example, by switching the direction of the direction switching mirror 20 so that the inspection unit 10 can perform scanning in parallel, it becomes possible to deal with a plurality of moving pedestrian PEs. Appropriate check can be made about the target of.

〔others〕
The present invention is not limited to the above embodiment, and can be implemented in various embodiments without departing from the gist thereof.

First, in the above embodiment, the infrared light sensor is used as the motion sensor constituting the position detection unit 30, but the present invention is not limited to this, and various motion sensors such as a heat sensor may be adopted. Further, in the above example, two or three sets of infrared light sensors are arranged along the passage PT, and the infrared light IL is emitted in the X direction. However, how to attach the sensors, the number of sensors, and sensing. The range and the like are not limited to these, and various number methods and modes can be used. Further, for example, regarding the position detection of the pedestrian PE, for example, the detection start position of the pedestrian PE, that is, the measurement start position by the terahertz wave, and the detection end position of the pedestrian PE, that is, the measurement end position by the terahertz wave can be specified. , The position detection unit 30 may perform detection with a width in the traveling direction of the pedestrian PE.

In addition, the size of the direction switching mirror 20 can be changed in various ways. For example, when installed in a ticket gate or the like as in the above example, the size is such that the upper body of a passing pedestrian PE can be measured. , Setting the height in the Y direction, etc. can be considered. Further, regarding the direction switching mirror 20, the reflective surface in the plate-shaped portion may be one-sided or both-sided.

Further, in the above embodiment, the measurement using the terahertz wave is performed by one inspection unit 10 from the viewpoint of cost, but the measurement may be performed by two or more inspection units 10. For example, in the example of FIG. 1, in the passage housing CA having a pair of left and right, the inspection unit 10 and the direction switching mirror 20 are installed not only on the left side (+ X side) in the traveling direction but also on the right side (−X side). And so on. Alternatively, the measurement may be performed by changing the installation position and angle from the same direction. These enable highly accurate measurement with less blind spots.

Further, in the above, the moving body is a pedestrian, but the present invention may be applied to a moving body other than a pedestrian.

Further, in the above embodiment, the wavelength band of the terahertz wave TW is assumed to be a band having a frequency of 0.1 to 2 THz, but the present application is not limited to this, and the present application is applied to those including various terahertz wavelength bands. be able to.

Further, in the above embodiment, the configuration inside the inspection unit 10 can be configured other than those exemplified in FIG. 3, and in the embodiment in FIG. 3, the galvano mirror is used as a scan-type reflective member. However, the present invention is not limited to this, and it is possible to apply a device that drives a light reflecting surface of various drive methods such as an electromagnetic drive type, an electrostatic method, a piezoelectric method, and a thermal method. can.

10 ... Inspection unit, 20 ... Direction switching mirror, 30 ... Position detection unit, 30A, 30B ... Infrared light sensor, 31-33 ... Sensor unit, 50 ... Control unit, 60 ... Image creation unit, 100 ... Mobile scanner, 200 ... Mobile scanner, 250 ... Control unit, 250A ... Periodic scan control unit, AX ... Central axis, BS ... Beam splitter, CA ... Passage housing, D1 ... Arrow, DR1-DR3 ... Direction, DS ... Display unit, GM ... Galvano mirror, IL, IL1-IL3 ... Infrared light, KN ... Knife, LS ... Lens, PE, PE1, PE2 ... Pedestrian (moving object), PT ... Passage, RP ... Reflection position, RW ... Reflection component, Rx ... Receiver, TW ... Terrahertz wave, Tx ... Transmitter

Claims (8)

An inspection unit that transmits terahertz waves in a predetermined wavelength band toward a moving object to be inspected, receives terahertz waves reflected from the moving object, and scans the moving object.
A position detector that detects the position of a moving object, and a position detector
A mobile scanner provided with a direction switching mirror that switches the propagation direction of the terahertz wave from the inspection unit according to the position of the moving object detected by the position detecting unit. The mobile scanner according to claim 1, wherein the inspection unit scans a moving object from different directions by switching with the direction switching mirror. The mobile scanner according to any one of claims 1 and 2, wherein the direction switching mirror switches the direction so as to scan a plurality of moving objects simultaneously existing in a scannable range in parallel. The mobile scanner according to any one of claims 1 to 3, wherein a plurality of position detection units are provided along the moving direction of the moving body. The mobile scanner according to claim 4, wherein the direction switching mirror is fixed in a posture determined for each movement detected by the plurality of position detection units. It is a body scanner that targets pedestrians as moving objects for inspection.
The inspection department scans a part of the human body and
The mobile scanner according to any one of claims 1 to 5, wherein the position detection unit is a motion sensor that detects a pedestrian. The mobile scanner according to any one of claims 1 to 6, further comprising an image creation unit that creates image data for each switching by the direction switching mirror based on the scanning result of the moving object by the inspection unit. A passage housing that forms a passage that defines the moving direction of the moving body and arranges the position detection unit along the passage is provided.
The mobile scanner according to any one of claims 1 to 7, wherein the direction switching mirror is provided on the side of the passage and irradiates a terahertz wave toward a moving body moving along the passage.

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