Patent Publication Number: US-2023140177-A1

Title: Embedded-object scanner device

Description:
CROSS-REFERENCE 
     The present application claims priority to Japanese patent application serial numbers 2019-032710 and 2019-032711 filed on Feb. 26, 2019, the contents of which are incorporated fully herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to an embedded-object scanner device, which is also known as a wall scanner. 
     BACKGROUND ART 
     Japanese Laid-open Patent Publication No. 2017-215185 and US Patent Publication No. 2017/0248727 disclose embedded-object scanner devices (wall scanners) that scan for embedded objects, such as rebar or nails, embedded in a target material, such as concrete, wood, ceramic or drywall. 
     SUMMARY OF THE INVENTION 
     To scan for embedded objects using an embedded-object scanner device, it might be necessary for a user to perform a sensing operation multiple times. However, to more easily perform such scanning work, there is demand for a technique that enables the user to efficiently (conveniently) check sensed data generated by the multiple sensing operations. 
     It is therefore a non-limiting object of the present teachings to disclose a technique that enables such scanning work to be performed more easily/conveniently. 
     According to one aspect of the present teachings, an embedded-object scanner device (wall scanner) may comprise: a housing; a sensing device, which is housed in the housing and senses one or more embedded objects embedded in a target material; and a display device, which is provided on the housing and collectively displays multiple sets of display data generated in multiple sensing operations performed by the sensing device, thereby enabling the sensed data to be checked by the user more efficiently and conveniently. 
     According to another aspect of the present teachings, an embedded-object scanner device (wall scanner) may comprise: a housing; a sensing device, which is housed in the housing and senses one or more embedded objects embedded in a target material; and an illumination device, which is provided on the housing and illuminates at least a portion of the surface of the target material, thereby enabling the scanning work to be performed more easily and accurately. 
     Additional aspects, objects, embodiments and advantages of the present teachings will become apparent upon reading the following detailed description in view of the appended drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a front view that schematically shows an embedded-object scanner device according to a representative embodiment of the present teachings. 
         FIG.  2    is a side view that schematically shows the embedded-object scanner device according to the embodiment of  FIG.  1   . 
         FIG.  3    is a top view that schematically shows the embedded-object scanner device according to the embodiment of  FIG.  1   . 
         FIG.  4    shows a battery-mounting part according to the embodiment of  FIG.  1   . 
         FIG.  5    is a functional block diagram that shows the embedded-object scanner device according to the embodiment of  FIG.  1   . 
         FIG.  6    shows a display example of a display device, according to the embodiment of  FIG.  1   , for use when starting and stopping an illumination device. 
         FIG.  7    shows a display example of the display device, according to the embodiment of  FIG.  1   , for use when adjusting the light intensity of illumination lights emitted from the illumination device. 
         FIG.  8    shows a display example of the display device, according to the embodiment of  FIG.  1   , for use when selecting a scan mode. 
         FIG.  9    shows a display example of the display device, according to the embodiment of  FIG.  1   , for use when scanning for embedded objects in a single-scan mode. 
         FIGS.  10 A and  10 B  respectively show two views for explaining an embedded-object scanning method, which utilizes the embodiment of  FIG.  1    in a single-scan mode. 
         FIG.  11    contains three views for explaining the embedded-object scanning method, which utilizes the embodiment of  FIG.  1    in a multi-scan mode. 
         FIG.  12    shows a display example of the display device after a first sensing operation has been performed in the single-scan or multi-scan mode. 
         FIG.  13    shows a display example of the display device after the first sensing operation has been performed in the multi-scan mode. 
         FIG.  14    shows a display example of the display device after a second sensing operation has been performed in the multi-scan mode. 
         FIG.  15    shows a display example of the display device after a third sensing operation has been performed in the multi-scan mode. 
         FIG.  16    shows a display example of the display device after the third sensing operation has been performed in the multi-scan mode. 
         FIG.  17    shows two views for explaining the embedded-object scanner method in the multi-scan mode. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Although embodiments according to the present invention will be explained below, with reference to the drawings, the present invention is not limited to the embodiments. 
     In the present embodiment, positional relationships between parts will be explained using the terms “left,” “right,” “front,” “rear,” “up,” and “down.” Each of these terms indicates a direction or a relative position with respect to the center of an embedded-object scanner device (wall scanner)  1 . 
     Overview of Embedded-Object Scanner Device (Wall Scanner) 
       FIG.  1    is a front view that schematically shows the embedded-object scanner device (wall scanner)  1  according to a representative, not limiting (present) embodiment of the present teachings.  FIG.  2    is a side view that schematically shows the embedded-object scanner device  1  according to the present embodiment.  FIG.  3    is a top view that schematically shows the embedded-object scanner device  1  according to the present embodiment. 
     The embedded-object scanner device  1  emits sensing waves into a target material OB to nondestructively inspect the target material OB. The embedded-object scanner device  1  scans for embedded objects embedded in the target material OB. A concrete wall is an illustrative example of a target material OB. A steel-reinforcing rod (“rebar”) embedded in the concrete wall is an illustrative example of an embedded object. However, the embedded-object scanner device  1  according to the present invention may be used to detect other types of embedded objects (e.g., nails, wood, etc.) in other types of target materials (e.g., wood, ceramic, drywall, etc.). 
     The embedded-object scanner device  1  comprises a housing  2 , rollers  3 , a sensing device  4 , one or more illumination devices  5 , one or more indicator devices  6 , a manual-operation device  7 , a display device (display)  8 , a battery-mounting part  9 , and a control device (controller, processor)  10 . 
     The housing  2  houses the sensing device  4  and the control device  10 . The housing  2  has: an upper surface  2 A, which faces upward; a lower surface  2 B, which faces downward; a left-side surface  2 C, which faces leftward; a right-side surface  2 D, which faces rightward; a front surface  2 E, which faces frontward; and a rear surface  2 F, which faces rearward. The housing  2  comprises a handle  2 H and covers at least a portion of the rollers  3 . A user can perform scanning work by holding the handle  2 H. Guidance parts  2 S are provided on/in at least a portion of the housing  2 . The guidance parts  2 S may include, e.g., slits, which are provided in the housing  2 . 
     The rollers  3  rotate about respective rotational axes AX when the rollers  3  contact a surface of the target material OB and the embedded-object scanner device  1  is rolled rightward or leftward. When the rollers  3  contact the surface of the target material OB, the front surface  2 E of the housing  2  opposes the surface of the target material OB. Because the rollers  3  are rotatably supported by at least a portion of the housing  2 , the user may hold the handle  2 H and move the housing  2  such that the rollers  3  rotate about rotational axes AX in the state in which the rollers  3  are in contact with the surface of the target material OB. Therefore, the embedded-object scanner device  1  can smoothly move across the surface of the target material OB owing to the rotation of the rollers  3 . 
     The embedded-object scanner device  1  scans for embedded objects while moving, in the left-right direction, across the surface of the target material OB. When scanning for embedded objects, the embedded-object scanner device  1  is disposed on the surface of the target material OB such that the rotational axes AX of the rollers  3  extend in the up-down direction. That is, in the present embodiment, the user causes the rollers  3  to rotate such that the embedded-object scanner device  1  moves in the left-right direction. 
     The rollers  3  are provided leftward and rightward of the center of the housing  2 . As was noted above, at least a portion of each roller  3  is covered by the housing  2 . 
     The sensing waves emitted from the sensing device  4  strike the target material OB to sense embedded objects that are embedded in the target material OB. The sensing device  4  has a sensing surface  4 S that, in the state in which the rollers  3  and the surface of the target material OB are in contact, opposes the target material OB across at least a portion of the housing  2 . The sensing surface  4 S is disposed between the pair of rollers  3 . 
     The position of the center of the housing  2  and the position of the center of the sensing surface  4 S preferably at least substantially coincide in the left-right direction. 
     The sensing surface  4 S includes an emitting part (transmitter), which emits the sensing waves, and a receiving part (receiver), which receives sensing waves that were reflected by one or more embedded objects. Sensing waves emitted from the sensing surface  4 S to the target material OB via the front surface  2 E pass through the target material OB and strike the embedded object(s) and some of the sensing waves are reflected by the embedded object(s). Some of the sensing waves reflected by the embedded object(s) impinge on the sensing surface  4 S via the front surface  2 E. The sensing device  4  receives the sensing waves reflected by the embedded object(s), which enables the shape(s) and location(s) of the embedded object(s) to be sensed (detected). In the present embodiment, the sensing waves may be radio waves. In this case, the sensing device  4  may be a radar device. However, it is noted that in an alternate embodiment the sensing waves may be ultrasonic waves. 
     While the rollers  3  contact the surface of the target material OB and sensing waves are being emitted from the sensing surface  4 S, the user holds the handle  2 H and moves the housing  2  in the left-right direction such that the rollers  3  rotate about the rotational axes AX. That is, while the sensing surface  4 S is opposing the surface of the target material OB and sensing waves are being emitted from the sensing surface  4 S, the user moves the housing  2  such that the sensing device  4  is moved in the left-right direction. The sensing device  4  senses (detects) the embedded object(s) while being moved in the left-right direction. The embedded-object scanner device  1  can, while moving across the surface of the target material OB in the left-right direction, scan for embedded objects in a plurality of regions (areas) of the target material OB, as will be further discussed below. 
     The illumination device(s)  5  illuminate(s) at least portions of the surface of the target material OB. The illumination device(s)  5  is/are provided on the housing  2 . For example, when the rollers  3  are in contact with the surface of the target material OB, the illumination device(s)  5  may illuminate, with illumination light(s) IL, one or more portions of the surface of the target material OB around the housing  2 . The illumination device(s)  5  may comprise, e.g., LEDs (light-emitting diodes). 
     In the present embodiment, multiple illumination devices  5  are provided and comprise: illumination-light-emitting parts  51 , which respectively emit illumination lights IL from the housing  2  in the left and right directions; and an illumination-light-emitting part  52 , which emits illumination light IL from the housing  2  in the up-down direction. The illumination-light-emitting parts  51  and the illumination-light-emitting part  52  are each provided on an outer surface of the housing  2 . 
     The illumination-light-emitting parts  51  are provided on edges of the outer surface of the housing  2  in the left-right direction. The illumination-light-emitting parts  51  may comprise: a left illumination-light-emitting part  51 L, which emits illumination light IL from the housing  2  leftward; and a right illumination-light-emitting part  51 R, which emits illumination light IL from the housing  2  rightward. The left illumination-light-emitting part  51 L is provided on the left-side surface  2 C of the housing  2 . The right illumination-light-emitting part  51 R is provided on the right-side surface  2 D of the housing  2 . The left illumination-light-emitting part  51 L illuminates at least a portion of the surface of the target material OB that is leftward of the housing  2 . The right illumination-light-emitting part  51 R illuminates at least a portion of the surface of the target material OB that is rightward of the housing  2 . 
     The illumination-light-emitting part  52  is provided on an edge of the outer surface of the housing  2  in the up-down direction. In the present embodiment, the illumination-light-emitting part  52  is an upper illumination-light-emitting part that emits illumination light IL from the housing  2  in the up direction. The illumination-light-emitting part  52  is provided on the upper surface  2 A of the housing  2  and illuminates at least a portion of the surface of the target material OB that is upward of the housing  2 . 
     It is noted that the illumination-light-emitting part  52  may further comprise a lower illumination-light-emitting part that emits illumination light IL from the housing  2  in the down direction. The lower illumination-light-emitting part would be provided on the lower surface  2 B of the housing  2  and would illuminate at least a portion of the surface of the target material OB that is downward of the housing  2 . 
     The positions of the illumination-light-emitting parts  51  and the position of the center of the sensing surface  4 S preferably at least substantially coincide in the up-down direction (i.e. the length direction of the device  1 ). The position of the illumination-light-emitting part  52  and the position of the center of the sensing surface  4 S preferably at least substantially coincide in the left-right direction (i.e. the width direction of the device  1 ). 
     The indicator devices  6  indicate the position of the sensing surface  4 S in the housing  2  and are provided on the housing  2 . Preferably, the indicator devices  6  indicate the position of the center of the sensing surface  4 S in the up-down direction. In addition or in the alternative, a pair of indicator devices  6  could be provided on each of the left and right sides (edges) of the device  1  and may respectively indicate the range (length) of the scanning surface  4 S in the up-down direction. 
     In the present embodiment, the indicator devices  6  comprise laser-light emitting parts  61 , which respectively emit laser lights GL in the left and right directions. Thus, the indicator devices  6  may be laser devices, e.g., laser diodes. 
     The laser-light emitting parts  61  are respectively provided on the left and right sides (edges) of the outer surface of the housing  2  in the left-right direction. The laser-light emitting parts  61  comprise: a left laser-light-emitting part  61 L, which emits laser light GL from the housing  2  leftward; and a right laser-light-emitting part  61 R, which emits laser light GL from the housing  2  rightward. More specifically, the left laser-light-emitting part  61 L is provided on the left-side surface  2 C of the housing  2 . The right laser-light-emitting part  61 R is provided on the right-side surface  2 D of the housing  2 . The left laser-light-emitting part  61 L illuminates, with laser light GL, at least a portion of the surface of the target material OB that is leftward of the housing  2 . The right laser-light-emitting part  61 R illuminates, with laser light GL, at least a portion of the surface of the target material OB that is rightward of the housing  2 . 
     The positions of the laser-light emitting parts  61  and the position of the center of the sensing surface  4 S preferably at least substantially coincide in the up-down direction. 
     The laser-light emitting parts  61  are disposed rearward of the illumination-light-emitting parts  51 , as shown in  FIG.  2   . The positions of the laser-light emitting parts  61  and the positions of the illumination-light-emitting parts  51  preferably at least substantially coincide in the up-down direction. 
     In the left-right direction, the distance between the center of the housing  2  and the laser-light emitting parts  61  is shorter than the distance between the center of the housing  2  and the edges of the housing  2 . That is, the left laser-light-emitting part  61 L is provided at a location that is closer to the center of the housing  2  than is an outermost left edge of the housing  2 . The right laser-light-emitting part  61 R is provided at a location that is closer to the center of the housing  2  than is an outermost right edge of the housing  2 . 
     In addition, in the left-right direction, the distance between the center of the housing  2  and the laser-light emitting parts  61  is shorter than the distance between the center of the housing  2  and the illumination-light-emitting parts  51 . That is, the left laser-light-emitting part  61 L is provided at a location that is closer to the center of the housing  2  than is the left illumination-light-emitting part  51 L. The right laser-light-emitting part  61 R is provided at a location that is closer to the center of the housing  2  than is the right illumination-light-emitting part  51 R. 
     The manual-operation device  7  generates manual-operation signals in accordance with manual operation (e.g., pressing) of the manual-operation device  7  by the user. In the present embodiment, the manual-operation device  7  generates manual-operation signals for at least the illumination devices  5 . 
     The manual-operation signals for the illumination devices  5  preferably include a start signal, which starts (turns ON) the illumination devices  5 . The manual-operation signals for the illumination devices  5  also preferably include a stop signal, which stops (turns OFF) the illumination devices  5 . The manual-operation signals for the illumination devices  5  may also include a light-intensity adjusting signal, which adjusts the light intensity of the illumination lights IL emitted from the illumination devices  5 . The illumination devices  5  are started and stopped by manually operating (pressing one or more buttons on) the manual-operation device  7 . The light intensity of illumination lights IL is adjusted by manually operating (pressing one or more buttons on) the manual-operation device  7 . 
     The manual-operation device  7  preferably comprises a plurality of buttons (button switches) disposed on the outer surface of the housing  2 . As shown in  FIG.  1   , in the present embodiment, the manual-operation device  7  comprises a POWER button  71 , a SETTINGS button  72 , a MENU button  73 , two MOVE buttons  74 , and an ENTER button  75 . The two MOVE buttons  74  include a MOVE LEFT button  74 L and a MOVE RIGHT button  74 R. 
     The POWER button  71  is pressed to switch between the starting and stopping of a power supply of (i.e. to turn ON and OFF) the embedded-object scanner device  1 . The SETTINGS button  72  is pressed to switch a SETTINGS screen displayed on the display device  8 . The MENU button  73  is pressed to switch a MENU screen displayed on the display device  8 . The MOVE buttons  74  are pressed to move a cursor or a selection frame displayed on the display device  8 . The ENTER button  75  is pressed to confirm (input) an option, from among a plurality of options displayed on the MENU screen or the SETTINGS screen, selected by the cursor or the selection frame. 
     The display device  8  is provided on the housing  2  and is configured to display a variety of types of display data. Flat panel displays, such as LCDs (liquid-crystal displays) and OELDs (organic electroluminescent displays, which are also known as organic EL displays), are illustrative examples of the display device  8  according to the present teachings. A touchscreen optionally be used as the display device  8 , in which case one or more of the buttons on the manual-operation device  7  may be omitted by providing corresponding icons to be touched on the touchscreen. 
     A battery  11  designed for a power tool is mounted on the battery-mounting part  9  and functions as the power supply of the embedded-object scanner device  1 . 
     The control device  10  controls the embedded-object scanner device  1  and comprises a computer system. For example, the control device  10  may comprise: an arithmetic-processing unit that includes a processor such as a CPU (central processing unit); a storage device (hereinafter, simply “storage”) that includes volatile memory, such as RAM (random-access memory), and nonvolatile memory, such as read-only memory (ROM); and an input/output interface. 
     Battery-Mounting Part 
       FIG.  4    shows the battery-mounting part  9  according to the present embodiment. As shown in  FIG.  4   , the battery-mounting part  9  comprises: a pair of guide rails  9 G, which guide the battery (battery pack, battery cartridge)  11 ; and connection terminals, which is connected to battery terminals of the battery  11 . The guide rails  9 G are arranged so as to extend in parallel in the left-right direction. The connection terminals are disposed between the pair of guide rails  9 G. 
     The battery  11  is a direct-current power supply that is used with power tools and, in particular, is used as the power supply of the embedded-object scanner device  1  of the present embodiment. The battery  11  comprises (contains) a plurality of lithium-ion battery cells that are rechargeable by a charger. The battery  11  is portable. The battery  11  supplies current (electric power) to the sensing device  4 , the illumination device(s)  5 , the indicator device(s)  6 , the manual-operation device  7 , the display device  8 , and the control device  10 . 
     The battery  11  comprises: two slide rails  11 G, which are respectively guided in the guide rails  9 G; battery terminals, which are connected to the connection terminals of the battery-mounting part  9 ; and a release (latching) button (tab)  11 B. 
     The slide rails  11 G are disposed parallel to one another so as to be guided in the guide rails  9 G of the battery-mounting part  9 . The battery terminals are disposed between the pair of slide rails  11 G. When the battery  11  is mounted on the battery-mounting part  9 , the battery terminals of the battery  11  are electrically connected with the connection terminals of the battery-mounting part  9 . 
     The release button  11 B is pressed to release the attachment (latching) of the battery  11  to the battery-mounting part  9 . 
     When the battery  11  is to be mounted on the battery-mounting part  9 , the user inserts the battery  11  into the battery-mounting part  9  from the rear of the battery-mounting part  9 . While the slide rails  11 G are being guided in the guide rails  9 G, the battery  11  is moved across the battery-mounting part  9  such that the battery terminals and the connection terminals come into contact and become connected. By virtue of the electrical connection of the battery terminals with the connection terminals, the battery  11  can supply current to a terminal block (not shown) disposed in the battery-mounting part  9 . 
     When the battery  11  is to be removed from the battery-mounting part  9 , the release button  11 B is pressed. By the pressing of the release button  11 B, the attachment (latching) of the battery  11  to the battery-mounting part  9  is released. After the attachment of the battery  11  to the battery-mounting part  9  has been released, the battery  11  is slid rearward and pulled out of the battery-mounting part  9 . 
     Control Device (Controller) 
       FIG.  5    is a functional block diagram that shows electrical components within the embedded-object scanner device  1  according to the present embodiment. As shown in  FIG.  5   , the control device (controller)  10  is connected to the manual-operation device  7 , a rotation sensor  30 , the sensing device  4 , the illumination device(s)  5 , the indicator device(s)  6 , the display device  8 , and a notifying device  12 . 
     The rotation sensor  30  detects both the rotational direction and the rotational angle of one or both of the rollers  3 . Sensed data generated by the rotation sensor  30  is output to the control device  10 . 
     The notifying device  12  outputs notification data. For example, the notifying device  12  may include an audio-output device or a light-emitting device, or both. The audio-output device may output sound(s) as the notification data. The light-emitting device may output light as the notification data. 
     The control device  10  comprises a sensing-control part  101 , a sensed-data acquiring part  102 , an illumination-control part  103 , an indicator-control part  104 , a display-control part  105 , a notification-control part  106 , and a storage  107 . 
     The sensing-control part  101  controls the sensing device  4 , in particular to cause the emitter part (transmitter) of the sensing surface  4 S to emit sensing waves. Therefore, the sensing-control part  101  outputs control instructions that control the operation of the sensing device  4 . In the present embodiment, the sensing-control part  101  outputs, e.g., control instructions to start and end each sensing operation performed by the sensing device  4 . 
     The sensed-data acquiring part  102  acquires sensed data output from the sensing device  4 , in particular acquires (inputs) data concerning sensing waves that were reflected back from embedded objects and received by the receiving part (receiver) of the sensing surface  4 S. Thus, the sensed-data acquiring part  102  acquires (input) sensed data that indicates one or more embedded objects sensed (detected) by the sensing device  4 . In addition, the sensed-data acquiring part  102  also may acquire (input) the sensed data output from the rotation sensor  30 . 
     The illumination-control part  103  controls the illumination devices  5 , e.g., based on manual-operation signals output from the manual-operation device  7 . For example, if a start signal (one type of manual-operation signal) has been output from the manual-operation device  7 , then the illumination-control part  103  causes one or more illumination lights IL to be emitted from the illumination devices  5 . Thereby, at least a portion of the surface of the target material OB is illuminated by illumination lights IL. If a stop signal (another type of manual-operation signal) has been output from the manual-operation device  7 , then the illumination-control part  103  causes the emission of the illumination light(s(IL from the illumination device(s)  5  to stop. If a light-intensity adjusting signal (another type of manual-operation signal) has been output from the manual-operation device  7 , then the illumination-control part  103  adjusts the light intensity of the illumination light(s) IL emitted from the illumination device(s)  5 . 
       FIG.  6    shows a display example of the display device  8 , according to the present embodiment, for use when starting and stopping the illumination devices  5 . As shown in  FIG.  6   , when starting and stopping the illumination devices  5 , the user manually operates the manual-operation device  7  to cause the SETTINGS screen, which is for use when starting and stopping the illumination devices  5 , to be displayed on the display device  8 . More specifically, the user presses the SETTINGS button  72  and the MENU button  73  to cause the SETTINGS screen as shown in  FIG.  6    to be displayed on the display device  8 . Then, the user presses the MOVE buttons  74  so that a selection frame Fa surrounds “LIGHT” and thereafter presses the ENTER button  75 . When one or more of the illumination devices  5  is to be started, the user, in the state in which “LIGHT” has been selected, presses the MOVE buttons  74  so that a selection frame Fb surrounds “ON” and then presses the ENTER button  75 . Thereby, illumination light(s) IL is/are emitted from the illumination device(s)  5 . If the illumination devices  5  are to be stopped (turned OFF), then the user, in the state in which “LIGHT” has been selected, presses the MOVE buttons  74  so that the selection frame Fb surrounds “OFF” and then presses the ENTER button  75 . Thereby, the emission of the illumination lights IL from the illumination devices  5  is stopped. 
       FIG.  7    shows another display example of the display device  8 , according to the present embodiment, for use when adjusting the light intensity of the illumination light(s) IL emitted from the illumination device(s)  5 . As shown in  FIG.  7   , when adjusting the light intensity of the illumination light(s) IL emitted from the illumination device(s)  5 , the user manually operates the manual-operation device  7  to cause the SETTINGS screen for adjusting the light intensity of the illumination lights IL to be displayed on the display device  8 . More specifically, the user presses the SETTINGS button  72  and the MENU button  73  to cause the SETTINGS screen as shown in  FIG.  7    to be displayed on the display device  8 . The user then presses the MOVE buttons  74  so that the selection frame Fa surrounds “LIGHT” and thereafter presses the ENTER button  75 . If the light intensity of illumination lights IL is to be increased, then the user, in the state in which “LIGHT” has been selected, presses the MOVE buttons  74  so that a selection frame Fc surrounds “BRIGHTER” and then presses the ENTER button  75 . Thereby, the light intensity of the illumination light(s) IL emitted from the illumination device(s)  5  is increased. If the light intensity of illumination light(s) IL is to be decreased, then the user, in the state in which “LIGHT” has been selected, presses the MOVE buttons  74  so that the selection frame Fc surrounds “DARKER” and then presses the ENTER button  75 . Thereby, the light intensity of the illumination light(s) IL emitted from the illumination device(s)  5  is decreased. 
     The indicator-control part  104  controls the indicator devices  6 , e.g., based on manual-operation signals output from the manual-operation device  7 . For example, if a start signal (one type of manual-operation signal) has been output from the manual-operation device  7 , then the indicator-control part  104  causes one or more laser lights GL to be emitted from the indicator devices  6 . Thereby, at least a portion of the surface of the target material OB is illuminated by laser light(s) GL. If a stop signal (another type of manual-operation signal) has been output from the manual-operation device  7 , then the indicator-control part  104  causes the emission of laser light(s) GL from the indicator device(s)  6  to be stopped (turned OFF). If a light-intensity adjusting signal (another type of manual-operation signal) has been output from the manual-operation device  7 , then the indicator-control part  104  adjusts the light intensity of the laser light(s) GL emitted from the indicator device(s)  6 . 
     As shown in  FIG.  6   , when the indicator device(s)  6  is/are to be started or stopped, the user manually operates the manual-operation device  7  to cause the SETTINGS screen for starting and stopping the indicator device(s)  6  to be displayed on the display device  8 . The user presses the SETTINGS button  72  and the MENU button  73  to cause the SETTINGS screen, as shown in  FIG.  6   , to be displayed on the display device  8 . The user presses the MOVE buttons  74  so that the selection frame Fa surrounds “LASER” and then presses the ENTER button  75 . If the indicator device(s)  6  is/are to be started (turned ON), then the user, in the state in which “LASER” has been selected, presses the MOVE buttons  74  so that the selection frame Fb surrounds “ON” and then presses the ENTER button  75 . Thereby, laser light(s) GL is/are emitted from the indicator device(s)  6 . If the indicator device(s)  6  is/are to be stopped (turned off), then the user, in the state in which “LASER” has been selected, presses the MOVE buttons  74  so that the selection frame Fb surrounds “OFF” and then presses the ENTER button  75 . Thereby, the emission of the laser light(s) GL from the indicator device(s)  6  is stopped. 
     As shown in  FIG.  7   , to adjust the light intensity of the laser light(s) GL emitted from the indicator device(s)  6 , the user manually operates the manual-operation device  7  so as to cause the SETTINGS screen for adjusting the light intensity of the laser light(s) GL to be displayed on the display device  8 . The user presses the SETTINGS button  72  and the MENU button  73  and thereby causes the SETTINGS screen as shown in  FIG.  7    to be displayed on the display device  8 . The user presses the MOVE buttons  74  so that the selection frame Fa surrounds “LASER” and then presses the ENTER button  75 . If the light intensity of laser light(s) GL is to be increased, then the user, in the state in which “LASER” has been selected, presses the MOVE buttons  74  so that the selection frame Fc surrounds “BRIGHTER” and then presses the ENTER button  75 . Thereby, the light intensity of the laser light(s) GL emitted from the indicator device(s)  6  is increased. If the light intensity of laser light(s) GL is to be decreased, then the user, in the state in which “LASER” has been selected, presses the MOVE buttons  74  so that the selection frame Fc surrounds “DARKER” and then presses the ENTER button  75 . Thereby, the light intensity of the laser light(s) GL emitted from the indicator device(s)  6  is decreased. 
     The display-control part  105  controls the display device  8 , e.g., to cause prescribed display data to be displayed on the display device  8 . 
     The notification-control part  106  controls the notifying device  12 . For example, the notification-control part  106  may be configured to output prescribed sounds from the audio-output device as a type of notification to the user. In addition or in the alternative, the notification-control part  106  may be configured to cause prescribed light to be output from the light-emitting device as another type of notification to the user. 
     The storage  107  stores the sensed data of the sensing device  4  acquired by (input to) the sensed-data acquiring part  102 , e.g., based on control instructions for the start and end of the sensing operation output from the sensing-control part  101 . 
     Selection of the Scan Mode 
     The embedded-object scanner device  1  can scan for embedded objects in each of a plurality of scan modes that include a first scan mode and a second scan mode. In the present embodiment, the first scan mode is a single-scan mode that displays, on the display device  8 , the display data generated in a single sensing operation performed by the sensing device  4 . The second scan mode is a multi-scan mode that displays, collectively on the display device  8 , multiple sets of display data generated by multiple sensing operations performed by the sensing device  4 . The user can select the scan mode by manually operating (pressing one or more buttons on) the manual-operation device  7 , as will described below. 
       FIG.  8    shows another display example of the display device  8 , according to the present embodiment, for use when selecting the scan mode. As shown in  FIG.  8   , when the POWER button  71  is pressed to start the power supply of (turn ON) the embedded-object scanner device  1 , the MENU screen for selecting the scan mode is displayed on the display device  8 . If the single-scan mode is to be selected, the user presses the MOVE buttons  74  so that a selection frame Fd surrounds “SINGLE” and then presses the ENTER button  75 . Thereby, the embedded-object scanner device  1  scans for embedded objects in the single-scan mode. If the multi-scan mode is to be selected, then the user presses the MOVE buttons  74  so that the selection frame Fd surrounds “MULTI” and then presses the ENTER button  75 . Thereby, the embedded-object scanner device  1  scans for embedded objects in the multi-scan mode. 
     Single-Scan Mode 
       FIG.  9    shows another display example of the display device  8 , according to the present embodiment, for use when scanning for embedded objects in the single-scan mode. 
     As shown in  FIG.  9   , in the single-scan mode, the display-control part  105  causes a centerline  81 , which indicates the center of the housing  2  in the left-right direction, and edge lines  82 , which indicate the left and right edges of the housing  2  (or, the left and right edges of the sensing surface  4 S), to be displayed on the display device  8 . 
     More specifically, the edge lines  82  include a left edge line  82 L, which indicates the left edge of the housing  2  (or the sensing surface  4 S), and a right edge line  82 R, which indicates a right edge of the housing  2  (or the sensing surface  4 S). 
     The centerline  81  is displayed such that it extends in the up-down direction in a central portion of the display screen of the display device  8 . The left edge line  82 L is displayed leftward of the centerline  81 . The right edge line  82 R is displayed rightward of the centerline  81 . The left edge line  82 L and the right edge line  82 R are displayed such that they extend in the up-down direction on the display screen of the display device  8  in parallel with the centerline  81 . 
     The display-control part  105  causes a surface line  83 , which indicates the surface of the target material OB, to be displayed on the display device  8 . The surface line  83  is displayed such that it extends in the left-right direction at an upper part of the display screen of the display device  8 . 
     The display-control part  105  causes depth lines  84 , which indicate the distance from the surface of the target material OB in the front-rear direction, to be displayed on the display device  8 . The depth lines  84  are displayed such that they extend in the up-down direction at the left edge and the right edge of the display screen of the display device  8 . The up-down direction of the display screen of the display device  8  corresponds to the front-rear direction of the target material OB, which corresponds to the depth direction extending from the surface of the target material OB. Numerical values, which indicate distances from the surface of the target material OB in the depth direction, are displayed next to each depth line  84 . 
     The display-control part  105  causes an icon  85 , which simulates the embedded-object scanner device  1  on the surface of the target material OB, to be displayed on the display device  8 . 
     When the sensing surface  4 S is opposing the surface of the target material OB and sensing waves are being emitted from the sensing surface  4 S, the user causes the housing  2  to move such that the sensing device  4  is moved in the left-right direction. The sensed data generated by the sensing device  4  is acquired by (input to) the sensed-data acquiring part  102 . If one or more embedded objects has been sensed by the sensing device  4 , then the display-control part  105  causes an image or images BU of the embedded object(s) to be displayed on the display device  8 . 
     The position of the centerline  81 , the positions of the edge lines  82 , the position of the surface line  83 , and the positions of the depth lines  84  are each fixed on the display screen of the display device  8 . The positions of the images BU of embedded objects change on the display screen of the display device  8  based on the positions of embedded objects in the target material OB. The sensing device  4 , while being moved in the left-right direction, detects embedded objects. The positions of images BU of embedded objects change on the display screen of the display device  8  based on changes of the relative positions between the sensing device  4  and the embedded objects, as will be further explained below. 
     During the sensing operation performed by the sensing device  4 , the position of the centerline  81  on the display screen of the display device  8  is prescribed such that, when the position of the center of the housing  2  and the position of an embedded object coincide in the left-right direction, the centerline  81  and the image BU coincide on the display screen of the display device  8 . That is, when the position of the embedded-object scanner device  1  has been adjusted (moved) such that the centerline  81  and an image BU coincide on the display screen of the display device  8 , the position of the center of the housing  2  and the position of the corresponding embedded object coincide in the left-right direction. 
     In addition, during the sensing operation performed by the sensing device  4 , the position of each edge line  82  on the display screen of the display device  8  is prescribed such that, when the position of either of the edges of the housing  2  and the position of an embedded object coincide in the left-right direction, the corresponding edge line  82  and the corresponding image BU on the display screen of the display device  8  coincide. That is, when the position of the embedded-object scanner device  1  has been adjusted (moved) such that the left edge line  82 L and an image BU on the display screen of the display device  8  coincide, the position of the left edge of the housing  2  (or left edge of the sensing surface  4 S) and the position of the corresponding embedded object coincide in the left-right direction. Similarly, when the position of the embedded-object scanner device  1  has been adjusted (moved) such that the right edge line  82 R and an image BU on the display screen of the display device  8  coincide, the position of the right edge of the housing  2  (or the right edge of the sensing surface  4 S) and the position of the corresponding embedded object coincide in the left-right direction. 
     The display-control part  105  causes the image(s) BU of one or more embedded objects present between the center of the housing  2  and either of the edges of the housing  2  (or the edges of the sensing surface  4 S) in the left-right direction to be displayed on the display device  8  using a first display indicia. The display-control part  105  causes the image(s) BU of one or more embedded objects present outward of the housing  2  (or outward of the edges of the sensing surface  4 S) in the left-right direction to be displayed on the display device  8  using a second display indicia, which differs from the first display indicia, as will be further described below. 
     Therefore, one or more embedded objects present between the center of the housing  2  and the edges of the housing  2  (or the edges of the sensing surface  4 S) in the left-right direction is/are embedded object(s) that is/are present between the left edge and the right edge of the housing  2 . In other words, the one or more embedded objects present between the center of the housing  2  and the edges of the housing  2  (or the edges of the sensing surface  4 S) in the left-right direction is/are embedded object(s) that is/are present at a position or positions at which it/they oppose(s) the embedded-object scanner device  1 . 
     Embedded objects present outward of the housing  2  in the left-right direction are embedded objects that are present outward of the left edge or the right edge of the housing  2  (or the left and right edges of the sensing surface  4 S). In other words, embedded objects present outward of the housing  2  in the left-right direction (or outward of the left and right edges of the sensing surface  4 S) are embedded objects present at positions at which they do not oppose the embedded-object scanner device  1 . 
     In the explanation below, the state in which an embedded object is present between the left edge and the right edge of the housing  2  may be called the “opposing state” where appropriate, and the state in which an embedded object is present outward of the left edge or the right edge of the housing  2  (or outward of the left and right edges of the sensing surface  4 S) may be called the “non-opposing state” where appropriate. 
     In the interval during which a embedded object is sensed while the sensing device  4  is being moved in the left-right direction, the position of the embedded object changes from the opposing state to the non-opposing state, or vice versa. The display-control part  105  causes the image BU of an embedded object in the opposing state to be displayed on the display device  8  using the first display indicia. Furthermore, the display-control part  105  causes the image BU of an embedded object in the non-opposing state to be displayed on the display device  8  using the second display indicia. 
     More specifically, as shown in  FIG.  9   , the display-control part  105  causes the image BU of an embedded object in the opposing state to be displayed on the display device  8  using the first display indicia, which is a first mark  86  in the present embodiment. On the other hand, the display-control part  105  causes the image BU of an embedded object in the non-opposing state to be displayed on the display device  8  using the second display indicia, which is a second mark  87  in the present embodiment. To distinguish between the first display indicia and the second display indicia, for example and without limitation, the dimensions of the first mark  86  may be larger than the dimensions of the second mark  87 . In addition or in the alternative, the brightness of the first mark  86  may be higher (brighter) than the brightness of the second mark  87 . In addition or in the alternative, the display-control part  105  may cause the images BU to be displayed on the display device  8  such that images BU of embedded objects in the opposing state are accentuated (highlighted) more than images BU of embedded objects in the non-opposing state. If the display device  8  is a color display, images BU of embedded objects in the opposing state may be displayed in a different color than images BU of embedded objects in the non-opposing state. 
     The display device  8  displays the centerline  81 , which indicates the center of the housing  2  in the left-right direction, and the pair of edge lines  82 , which indicate the edges of the housing  2  in the left-right direction (or the left and right edges of the sensing surface  4 S). As shown in  FIG.  9   , the display device  8  displays, using the first display indicia (e.g., first mark  86 ), the image BU of an embedded object that is located between the pair of edge lines  82 , and displays, using the second display indicia (e.g., second mark  87 ), the images BU of embedded objects outward of the edge lines  82 . If an embedded object changes from the opposing state to the non-opposing state, then the display device  8  changes from the state in which it displays the first mark  86  to the state in which it displays the second mark  87 . On the other hand, if an embedded object changes from the non-opposing state to the opposing state, then the display device  8  changes from the state in which it displays the second mark  87  to the state in which it displays the first mark  86 . 
       FIGS.  10 A and  10 B  show two views for explaining an embedded-object scanning method in the single-scan mode according to the present embodiment. 
     The user scans for embedded objects by moving the embedded-object scanner device  1  with the sensing surface  4 S opposing the surface of the target material OB and sensing waves being emitted from the sensing surface  4 S. If an embedded object is detected by the sensing device  4 , then an image BU of the embedded object is displayed on the display device  8 . As shown in  FIG.  10 A , the user may adjust (move) the position of the embedded-object scanner device  1  such that the centerline  81  coincides with the image BU of the embedded object on the display screen of the display device  8 . 
     If an image BU of an embedded object is present between the left edge line  82 L and the right edge line  82 R, then the display device  8  displays the image BU of that embedded object using the first display indicia. More specifically, the display device  8  displays the image BU of that embedded object, which is in the opposing state, such that it is accentuated by the first mark  86 . The user, while viewing the first mark  86 , may then adjust (move) the position of the embedded-object scanner device  1  such that the centerline  81  coincides with the image BU of the embedded object on the display screen of the display device  8 . In other words, the user may adjust (move) the position of the embedded-object scanner device  1  such that the centerline  81  coincides with the first mark  86  on the display screen of the display device  8 . When the position of the embedded-object scanner device  1  is adjusted (moved) such that the centerline  81  coincided with the image BU of the embedded object, the position of the center of the housing  2  coincides with the position of the embedded object in the left-right direction. 
     After the user has made the centerline  81  coincide with the image BU of the embedded object on the display screen of the display device  8 , the user may use a marker (e.g., pencil) to mark the surface of the target material OB with a mark Ma. For example, the user may mark the surface of the target material OB upward of the housing  2  with the mark Ma at the center of the sensing surface  4 S in the left-right direction. 
     As was mentioned above, the position of the illumination-light-emitting part  52  at least substantially coincides with the position of the center of the sensing surface  4 S in the left-right direction. In addition, the position of the center of the housing  2  coincides with the position of the center of the sensing surface  4 S in the left-right direction. When the centerline  81  is made to coincide with the image BU of an embedded object on the display screen, the mark Ma can be applied at the position of the center of the sensing surface  4 S in the left-right direction by using the illumination-light-emitting part  52  as an indicator of the position of the center of the sensing surface  4 S. 
     In the present embodiment, the surface of the target material OB upward of the housing  2  is illuminated by illumination light IL emitted from the illumination-light-emitting part  52 . Consequently, even if the target material OB is located in a space that is dark, the user can apply the mark Ma in an easy and accurate manner. 
     After marking the surface of the target material OB with the mark Ma, the user moves the housing  2  in the left-right direction, with the rollers  3  in contact with the surface of the target material OB and sensing waves being emitted from the sensing surface  4 S, such that the rollers  3  rotate about rotational axes AX. As shown in  FIG.  10 B , the user adjusts (moves) the position of the embedded-object scanner device  1  such that the left edge line  82 L coincides with the image BU of the embedded object on the display screen of the display device  8 . 
     If the image BU of an embedded object is located either on the left edge line  82 L or outward of the left edge line  82 L, then the display device  8  displays the image BU of that embedded object using the second display indicia. More specifically, the display device  8  displays the image BU of that embedded object, which is in the non-opposing state, using the second mark  87 . While viewing the second mark  87 , the user may adjust the position of the embedded-object scanner device  1  such that the left edge line  82 L coincides with the image BU of the embedded object on the display screen of the display device  8 . For example, the user may adjust (move) the position of the embedded-object scanner device  1  such that the left edge line  82 L coincides with the second mark  87  on the display screen of the display device  8 . Thus, when the position of the embedded-object scanner device  1  has been adjusted (moved) such that the left edge line  82 L coincides with the image BU of the embedded object, the position of the left edge of the housing  2  coincides with the position of the embedded object. 
     After making the left edge line  82 L coincide with the image BU of the embedded object on the display screen of the display device  8 , the user may uses the marker (e.g., pencil) to mark the surface of the target material OB with a mark Mb. For example, the user may mark the surface of the target material OB leftward of the housing  2  with the mark Mb in the vicinity of the left edge of the housing  2  and within the illumination area of the laser light GL emitted from the left laser-light-emitting part  61 L. 
     The position of the left laser-light-emitting part  61 L, the position of the laser light GL emitted from the left laser-light-emitting part  61 L, and the position of the center of the sensing surface  4 S substantially coincide in the up-down direction. In addition, the position of the left edge of the housing  2  coincides with the position of the embedded object in the left-right direction. Consequently, when the left edge line  82 L is made to coincide with the image BU of the embedded object, by virtue of the mark Mb being applied to the surface of the target material OB in the vicinity of the left edge of the housing  2 , in which vicinity the laser light GL serves as an indicator, the user can apply the mark Mb at the position of the center of the sensing surface  4 S in the state shown in  FIG.  10 A . That is, the user can mark the surface of the target material OB with the mark Mb at the position at which the embedded object is present. 
     In the present embodiment, the surface of the target material OB leftward of the housing  2  is illuminated by illumination light IL emitted from the left illumination-light-emitting part  51 L. Consequently, even if the target material OB is in a space that is dark, the user can easily and accurately apply the mark Mb on the target material OB. 
     The work of marking the surface of the target material OB leftward of the housing  2  with the mark Mb was explained above. After completing the work that was explained with reference to  FIG.  10 A , the user can then mark the surface of the target material OB rightward of the housing  2  with the mark Mb by moving the embedded-object scanner device  1  leftward. 
     Multi-Scan Mode 
     Next, the multi-scan mode of the present embedded-object scanner method will be explained with reference to  FIG.  11   . 
     The multi-scan mode is a scan mode in which multiple sets of display data, which are generated by multiple sensing operations performed by the sensing device  4 , are displayed collectively on the display device  8 . As shown in  FIG.  11   , the user moves the embedded-object scanner device  1 , with the sensing surface  4 S opposing the surface of the target material OB, such that the sensing device  4  performs multiple sensing operations, more specifically three sensing operations in the up-down direction. 
     The sensing operations performed by the sensing device  4  include a manual-operation in which the sensing device  4  is moved (manually pushed) across the surface of the target material OB in the left-right direction. In the present embodiment, the sensing operations performed by the sensing device  4  include: a first sensing operation, in which the sensing device  4  is moved across a first area AR 1  of the surface of the target material OB in the left-right direction; a second sensing operation, in which the sensing device  4  is moved across a second area AR 2  of the surface of the target material OB in the left-right direction; and a third sensing operation, in which the sensing device  4  is moved across a third area AR 3  of the surface of the target material OB in the left-right direction. 
     In the present embodiment, the first area AR 1  is an area of the surface of the target material OB between position Pa and position Pb. The second area AR 2  is an area of the surface of the target material OB between position Pc and position Pd. The third area AR 3  is an area of the surface of the target material OB between position Pe and position Pf. The first area AR 1 , the second area AR 2 , and the third area AR 3  are defined in the up-down direction. In the present embodiment, the second area AR 2  is defined downward of the first area AR 1 . The third area AR 3  is defined downward of the second area AR 2 . 
     Position Pa and position Pb substantially coincide in the up-down direction. Position Pc and position Pd substantially coincide in the up-down direction. Position Pe and position Pf substantially coincide in the up-down direction. Position Pa, position Pc, and position Pe substantially coincide in the left-right direction. Position Pb, position Pd, and position Pf substantially coincide in the left-right direction. Thus, areas AR 1 , AR 2  and AR 3  define three areas of the target material OB that are adjacent in the up-down (vertical) direction. 
     When multiple (consecutive) sensing operations are to be performed, the sensing-control part  101  outputs control instructions for the start and end of each of the multiple sensing operations. In the present embodiment, the start of each sensing operation includes the start of the storage (writing) of the sensed data generated by the sensing device  4  in the storage  107 . The end of each sensing operation includes the end (termination) of the storage of the sensed data generated the sensing device  4  in the storage  107 . Thus, based on the control instructions output from the sensing-control part  101 , the storage  107  stores the sensed data of the sensing device  4 . When a control instruction for the start of a sensing operation has been output from the sensing-control part  101 , the storage  107  starts the storage of the sensed data generated by the sensing device  4  that was acquired by (input to) the sensed-data acquiring part  102 . When a control instruction for the end of a sensing operation has been output from the sensing-control part  101 , the storage  107  ends the storage of the sensed data generated by the sensing device  4 . 
     The storage  107  stores the sensed data generated by the sensing device  4  in association with data that indicates the position of the sensing device  4  (the embedded-object scanner device  1 ) at the time of generating the sensed data. For example, the position can be determined based on the output from the rotation sensor  30  from the start of the storage of the sensed data (the start of the corresponding sensing operation) until the end of the same (the end of the corresponding sensing operation). In this manner, for example, the distance in the left-right direction of the sensing device  4  (the embedded-object scanner device  1 ) from the start positions Pa, Pc and Pe can be calculated based on the output of the rotation sensor  30  during the respective sensing operations (taking into consideration, for example, the size/diameter of the rollers  3 ). 
     The sensing-control part  101  also generates and outputs the control instructions for the start and stop of each of the sensing operations based on the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB for the following reason. If the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB changes while the sensing waves are being emitted from the sensing surface  4 S, the intensity of the reflected sensing waves received by the sensing surface  4 S will change. That is, the shorter the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB, the higher the intensity of the reflected sensing waves received by the sensing surface  4 S becomes. On the other hand, the longer the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB, the lower the intensity of the reflected sensing waves received by the sensing surface  4 S becomes. Therefore, the sensing-control part  101  determines, based on the intensity of the reflected sensing waves received by the sensing surface  4 S, whether the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is above or below a predetermined distance threshold. If this distance is determined to be equal to or less than the predetermined distance threshold, then the sensing-control part  101  outputs, to the storage  107 , a control instruction to start the storage of sensed data. On the other hand, if the sensing-control part  101  determines that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is greater than the distance threshold, then the sensing-control part  101  outputs, to the storage  107 , a control instruction to end the storage of sensed data. The distance threshold value is set in advance based upon the characteristics and capabilities of the sensing device  4 . 
     The first sensing operation includes a manual operation in which, by rolling the rollers  3  across the surface of the target material OB, the sensing device  4  is moved across the first area AR 1  of the surface of the target material OB. When the embedded-object scanner device  1  approaches the surface of the target material OB at position Pa such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB becomes the predetermined distance threshold or less and while sensing waves are being emitted from the sensing surface  4 S, the storage  107  starts the storage of the sensed data generated by the sensing device  4 . After the storage of sensed data in the storage  107  has been started, the sensing device  4  is moved rightward from position Pa toward position Pb while the sensing surface  4 S continues to oppose the surface of the target material OB and emit the sensing waves. After the sensing device  4  has reached position Pb, the embedded-object scanner device  1  is separated (pulled away) from the surface of the target material OB at position Pb such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB becomes greater than the predetermined distance threshold. Therefore, the sensing-control part  101  causes the storage  107  to end (terminate) the storage of the sensed data that was generated in the first sensing operation. Therefore, the sensed data generated by the sensing device  4  in (during) the first sensing operation is stored in the storage  107 . 
     After the first sensing operation has been completed, the second sensing operation is then performed. In the second sensing operation the sensing device  4  is moved across the second area AR 2  of the surface of the target material OB with the rollers  3  rotating while in contact with the surface of the target material OB. Similar to the first sensing operation, when the embedded-object scanner device  1  approaches the surface of the target material OB at position Pc such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is the distance threshold or less and sensing waves are being emitted from the sensing surface  4 S, the storage  107  starts the storage of the sensed data generated by the sensing device  4 . After the storage of sensed data by the storage  107  has been started, the sensing device  4  is moved rightward from position Pc to position Pd with the sensing surface  4 S opposing the surface of the target material OB and emitting sensing waves. After the sensing device  4  has reached position Pd, the embedded-object scanner device  1  is separated (pulled away) from the surface of the target material OB at position Pd such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is greater than the distance threshold. Therefore, the sensing-control part  101  causes storage  107  to end the storage of the sensed data generated in the second sensing operation. Therefore, the sensed data generated by the sensing device  4  in the second sensing operation is also stored in the storage  107 . 
     After the second sensing operation has been completed, the third sensing operation is then performed, in which the sensing device  4  is moved across the third area AR 3  of the surface of the target material OB with the rollers  3  rotating in contact with the target material OB. Similar to the first and second sensing operations, when the embedded-object scanner device  1  approaches the surface of the target material OB at position Pe such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is the distance threshold or less and the sensing waves are being emitted from the sensing surface  4 S, the storage  107  starts the storage of the sensed data generated by the sensing device  4 . After the storage of sensed data by the storage  107  has been started, the sensing device  4  is moved rightward from position Pe toward position Pf with the sensing surface  4 S opposing the surface of the target material OB and emitting sensing waves. After the sensing device  4  has reached position Pf, the embedded-object scanner device  1  is separated (pulled away) from the surface of the target material OB at position Pf such that the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB is greater than the distance threshold. Therefore, the sensing-control part  101  causes the storage  107  to end the storage of the sensed data generated in the third sensing operation. Therefore, the sensed data generated by the sensing device  4  in the third sensing operation is also stored in the storage  107 . 
       FIG.  12    shows another display example of the display device  8 , according to the present embodiment, for use after the first sensing operation has been performed. The multiple sensing operations are each performed in the same manner as in the single-scan mode described above. 
     As was just explained above, when the embedded-object scanner device  1  approaches the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB at position Pa is the distance threshold or less, the storage of the sensed data of the sensing device  4  by the storage  107  is started, and the first sensing operation is started. In the first sensing operation, the sensing device  4  is moved rightward from position Pa toward position Pb. At the point in time when the sensing device  4  has reached position Pb, display data D 1 , which includes the images BU of three embedded objects as indicated by one first mark  86  and two second marks  87 , is displayed on the display device  8  as shown in  FIG.  12   . 
       FIG.  13    shows another display example of the display device  8 , in which the images BU shown in  FIG.  12    have been moved upward so that additional images BU of embedded objects can be shown on the same display screen. More specifically, in the first sensing operation, when the sensing device  4  has reached position Pb and, at position Pb, when the embedded-object scanner device  1  is separated from the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB is greater than the distance threshold, the storage  107  ends the storage of the sensed data generated the sensing device  4  in the first sensing operation, such that the sensed data generated in the first sensing operation is stored in the storage  107 . The display-control part  105  generates display data D 1   r  based on the sensed data generated in the first sensing operation, which has been stored in the storage  107 . The display-control part  105  causes display data D 1   r  to be displayed on the display device  8 , as shown in  FIG.  13   . 
     Display data D 1   r  corresponds to display data in which display data D 1  has been reduced (compressed, shrunk) in the up-down direction. The display-control part  105  causes display data D 1   r  to be displayed in an upper portion of the display screen of the display device  8 . 
     In the present embodiment, by using the information that includes the positions of the embedded objects stored in the storage  107 , the display device  8  is configured to show the positions of all embedded objects in the area AR 1  detected during the first sensing operation. For example, the outer edges of the display of the display device  8  in  FIG.  13    may be used to indicate the boundaries of the area AR 1  in the left-right direction. Alternatively, for example, in case the area AR 1  is wider than the area that can be displayed on the display device  8 , only one of the outer edges of the display of the display device  8  in  FIG.  13    may be used to indicate the left or the right boundary of the area AR 1 . In another example, the area AR 1  may be displayed centered with respect to the vertical centerline of the display. In both of these examples, for example, objects that cannot be displayed on the display device  8 , because the area AR 1  is wider than the area of the display of the display device  8 , can be displayed by performing a scrolling operation, which will be described in more detail below. 
     After display data D 1   r  has been displayed, at position Pc, when the embedded-object scanner device  1  approaches the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB is the distance threshold or less, storage of the sensed data generated by the sensing device  4  in the storage  107  is started, and the second sensing operation is started. In the second sensing operation, the sensing device  4  is moved rightward from position Pc toward position Pd. At the point in time when the sensing device  4  has reached position Pd, display data D 2  (which may also include images BU of the same or other embedded objects with the first or second display indicia (first and second marks  86 ,  87 ) is displayed on the display device  8 , in a manner similar to  FIG.  12   . 
       FIG.  14    shows the first and second sets of sensed data displayed together on the same display screen. More specifically, when the sensing device  4  has reached position Pd in the second sensing operation and the embedded-object scanner device  1  is separated from the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB at position Pd is greater than the distance threshold, the storage  107  ends the storage of the sensed data generated by the sensing device  4  in the second sensing operation, such that the sensed data generated in the second sensing operation is stored in the storage  107 . Then, the display-control part  105  generates display data D 2   r  based on the sensed data generated in the second sensing operation, which is stored in the storage  107 . The display-control part  105  displays display data D 2   r , collectively with display data D 1   r , on the display device  8 . 
     Display data D 2   r  corresponds to display data in which display data D 2  has been reduced (compressed, shrunk) in the up-down direction. The display-control part  105  displays display data D 1   r  and display data D 2   r  such that they are lined up on the display screen of the display device  8 . In the example shown in  FIG.  14   , the display device  8  displays display data D 2   r  below display data D 1   r.    
     After display data D 1   r  and display data D 2   r  have been displayed, when the embedded-object scanner device  1  approaches the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB at position Pe is the distance threshold or less, storage of the sensed data generated by the sensing device  4  in the storage  107  is started, and thus the third sensing operation is started. In the third sensing operation, the sensing device  4  is moved rightward from position Pe toward position Pf. At the point in time when the sensing device  4  has reached position Pf, display data D 3  is displayed on the display device  8  again in a manner similar to  FIG.  12   . 
       FIG.  15    show the three sets of sensed data displayed together on the display screen. More specifically, in the third sensing operation, when the sensing device  4  has reached position Pf and the embedded-object scanner device  1  is separated from the surface of the target material OB such that the distance between the sensing surface  4 S and the surface of the target material OB at position Pf is greater than the distance threshold, the storage  107  ends the storage of the sensed data generated by the sensing device  4  in the third sensing operation such that the sensed data generated in the third sensing operation is stored in the storage  107 . The display-control part  105  then generates display data D 3   r  based on the sensed data generated in the third sensing operation, which is stored in the storage  107 . The display-control part  105  displays display data D 3   r , collectively with display data D 1   r  and display data D 2   r , on the display device  8 . 
     Display data D 3   r  corresponds to display data in which display data D 3  has been reduced (compressed, shrunk) in the up-down direction. The display-control part  105  displays display data D 1   r , display data D 2   r , and display data D 3   r  such that they are lined up on the display screen of the display device  8 . In the example shown in  FIG.  15   , the display device  8  displays display data D 3   r  below display data D 2   r.    
     Thus, in the multi-scan mode, the display device  8  collectively displays the multiple sets of display data D 1   r , D 2   r , D 3   r  generated in the multiple sensing operations performed by the sensing device  4 . The display device  8  displays the multiple sets of display data D 1   r , D 2   r , D 3   r  such that they are lined up. Therefore, the user can view a display of all embedded objects that are present in areas AR 1 , AR 2  and AR 3  at the same time, thereby giving the user a better understanding of the locations of the embedded objects over a wider area, than can be achieved in the single-scan mode. 
     In the present embodiment, the display-control part  105  is also configured to move the multiple sets of display data D 1   r , D 2   r , D 3   r  on the display screen of the display device  8  such that the multiple sets of display data D 1   r , D 2   r , D 3   r  move across the display screen in a synchronized manner. In the explanation below, the combination of display data D 1   r , D 2   r , D 3   r  will be called “aggregated display data Da” where appropriate. 
       FIG.  16    shows the display image of  FIG.  15    in the state of moving across display screen as a result of a scrolling operation. This feature of the present embodiment is achieved in the following manner. The storage  107  stores the multiple sets of display data D 1   r , D 2   r , D 3   r  generated in the multiple sensing operations. In addition, the storage  107  stores aggregated display data Da, which is a combination of the multiple sets of display data D 1   r , D 2   r , D 3   r  with the images BU of the embedded objects aligned in the same locations that they are present in the target material OB. The display-control part  105  can move the aggregated display data Da in the left-right direction on the display screen of the display device  8  based on aggregated display data Da stored in the storage  107 . That is, the display-control part  105  can scroll the aggregated display data Da in the left-right direction, in order to show a wider area of the target material OB than may be possible to view in one single image on the display screen. In addition, the display-control part  105  can display, on the display device  8 , an icon  88  that indicates that scrolling of the aggregated display data Da is in progress. In the example shown in  FIG.  16   , the icon  88  includes an arrow that indicates the scrolling direction of the aggregated display data Da. 
     In the present embodiment, the display-control part  105  causes the aggregated display data Da to move in the left-right direction synchronized with rotation of the rollers  3 . That is, if the user wishes to scroll the aggregated display data Da, then the user moves the housing  2  in the left-right direction while the rollers  3  are in contact with the surface of the target material OB. The rotation sensor  30  detects the rotation of the rollers  3 ; more particularly, the rotation sensor  30  senses the rotational speed and direction of the rollers  3 . The display-control part  105  moves the aggregated display data Da in the left-right direction in accordance with the sensed data (rotational speed and direction) generated by the rotation sensor  30 . 
     Because the rotation sensor  30  is configured to detect the rotational angle of the rollers  3  and the rotational direction of the rollers  3 , the display-control part  105  can adjust the scrolling of the aggregated display data Da based on the movement distance of the rollers  3 , which is calculated from the rotational angle of the rollers  3  sensed by the rotation sensor  30 . The display-control part  105  adjusts the scrolling direction of the aggregated display data Da based on the rotational direction of the rollers  3 . More specifically, if the rollers  3  are moving leftward, then the display-control part  105  scrolls the aggregated display data Da leftward; on the other hand, if the rollers  3  are moving rightward, then the display-control part  105  scrolls the aggregated display data Da rightward. If the user wishes to increase the scrolling speed of the aggregated display data Da, then, with the rollers  3  contacting the surface of the target material OB, the user moves the housing  2  at a higher speed in the left-right direction. On the other hand, if the user wishes to decrease the scrolling speed of the aggregated display data Da, then, with the rollers  3  contacting the surface of the target material OB, the user moves the housing  2  at a lower speed in the left-right direction. If the user wishes to scroll then aggregated display data Da leftward, then the user moves the housing  2  leftward while rolling the rollers  3  along the surface of the target material OB. If the user wishes to scroll the aggregated display data Da rightward, then the user moves the housing  2  rightward while rolling the rollers  3  along the surface of the target material OB. 
     The display-control part  105  displays, on the display device  8 , display data for the rotational speed of the rollers  3  based on the rotational speed of the rollers  3 , which is calculated from the rotational angle of the rollers  3  sensed by the rotation sensor  30 . If the sensed rotational speed of the rollers  3  becomes a predetermined speed or higher, then the display-control part  105  displays, on the display device  8 , display data that indicates that the rotational speed of the rollers  3  is the predetermined speed or higher. By checking this display data, the user can recognize that the movement speed of the embedded-object scanner device  1  is excessively high and can move the embedded-object scanner device  1  at a more appropriate speed. 
     In addition or in the alternative, if the sensed rotational speed of the rollers  3  becomes the predetermined speed or higher, then the notification-control part  106  may cause the notifying device  12  to operate. More specifically, the notification-control part  106  may cause a sound, which indicates that the rotational speed of the rollers  3  is the predetermined speed or higher, to be output from the audio-output device. In addition or in the alternative, the notification-control part  106  may cause the light-emitting device to operate in the light-emitting state, which indicates that the rotational speed of the rollers  3  is the predetermined speed or higher. By actuating the notifying device  12 , the user can be informed that the movement speed of the embedded-object scanner device  1  is excessively high and can move the embedded-object scanner device  1  at a more appropriate speed. 
     Guidance Parts 
       FIG.  17    includes two view for explaining another aspect of the embedded-object scanning method, according to the present embodiment, in the multi-scan mode. More specifically,  FIG.  17    shows the two guidance parts  2 S that are respectively provided on/in the housing  2  on the left and right sides thereof. The guidance parts  2 S may include slits, which are provided in (extend into) the housing  2 , or the guidance parts  2 S may be provided as marks (lines) that are provided (drawn, printed) on the surface of the housing  2 . 
     The guidance parts  2 S may be used by the user to guide the position of the housing  2  in the up-down direction when detecting the first area AR 1  and the second area AR 2 , which are defined in the up-down direction as shown in  FIG.  11   , using the sensing device  4 . The distance between the first area AR 1  and the second area AR 2  in the up-down direction can thus be set to a prescribed value by using the guidance parts  2 S as will be described below. 
     As shown in  FIG.  17   , before the first sensing operation is performed, a mark Mc is applied, using the left side guidance part  2 S as an indicator, to the surface of the target material OB. The mark Mc indicates the position of the guidance parts  2 S in the up-down direction. After the mark Mc has been applied to the target material OB and before the second sensing operation is performed, the position of the housing  2  is adjusted (moved downward) such that the positions of laser lights GL coincides with the position of the mark Mc, which was applied before the first sensing operation was performed, in the up-down direction. Thus, after the first sensing operation is completed by moving the device  1  rightward to the position shown in dotted lines in  FIG.  17   , the housing  2  can then be moved downward from the position (level) of the first sensing operation by the distance between the guidance parts  2 S and laser lights GL to the position shown in solid lines in  FIG.  17   . Thus, when the positions of laser lights GL coincide with the position of the mark Mc, the second sensing operation is performed. In this way, the distance between the first area AR 1  and the second area AR 2  in the up-down direction is made to be equal to the distance between the guidance parts  2 S and laser lights GL in the up-down direction. 
     Although not shown in  FIG.  17   , before the second sensing operation is performed while the positions of laser lights GL coincides with the position of the mark Mc, another mark may be applied to the surface of the target material OB using the left-side guidance part  2 S as an indicator. Therefore, before the third sensing operation is performed, the position of the housing  2  is adjusted (moved downward) such that the positions of laser lights GL coincides with the position of the second mark (not shown), which was applied before the second sensing operation was performed, in the up-down direction. Again, the housing  2  can thus be moved downward from the position (level) in the second sensing operation by the distance between the guidance parts  2 S and laser lights GL in the up-down direction. Thereafter, with the positions of laser lights GL coinciding with the position of the mark Mc, the third sensing operation is performed by moving the device  1  rightward from the second mark (not shown). In the up-down direction, the distance between the second area AR 2  and the third area AR 3  is again made to equal to the distance between the guidance parts  2 S and laser lights GL in the up-down direction. 
     Thus, by using the guidance parts  2 S, the distance between the first area AR 1  and the second area AR 2  in the up-down direction and the distance between the second area AR 2  and the third area AR 3  can be made to be the same distance, so that all of the areas AR 1 , AR 2  and AR 3  have the same height. 
     Advantages and Effects 
     According to the present embodiment as explained above, the embedded-object scanner device  1 , e.g., comprises the display device  8 , which collectively displays multiple sets of display data D 1   r , D 2   r , D 3   r  generated in multiple sensing operations performed by the sensing device  4 . Therefore, the user can efficiently check, based on display data D 1   r , D 2   r , D 3   r  displayed on the display device  8 , all of the sensed data generated by the sensing device  4  generated by the multiple sensing operations in one display image, thereby making the scanning results easier to review and understand. 
     Furthermore, because the display device  8  displays the multiple sets of display data D 1   r , D 2   r , D 3   r  lined up in the same spatial arrangement as the embedded objects in the target material OB, the user can easily confirm the positions and shapes of the embedded objects over a wider area than is possible in a single-scan mode. For example, as shown in  FIG.  15   , if the positions of images BU of the embedded objects in the left-right direction differ among multiple sets of display data D 1   r , D 2   r , D 3   r , then the user can confirm, based on display data D 1   r , D 2   r , D 3   r  displayed on the display device  8 , that the embedded objects are arrayed (disposed) in an arrangement that is tilted relative to the vertical (up-down) direction). 
     Owing to the provision of the guidance parts  2 S, the distance between (the heights of) the first area AR 1  and the second area AR 2  in the up-down direction can be set to a prescribed value as was explained with reference to  FIG.  17   . 
     Furthermore, as was explained with reference to  FIG.  16   , the display device  8  moves the multiple sets of display data D 1   r , D 2   r , D 3   r  on the display screen in a synchronized manner when the device  1  is scrolled across a surface. Thereby, the user can easily recheck the state (the locations) of embedded objects. In addition, the user can confirm the state (the locations) of embedded objects over a wide area. 
     The display device  8  can move display data D 1   r , D 2   r , D 3   r  synchronized with the rotation of the rollers  3 . Thereby, the user can scroll display data D 1   r , D 2   r , D 3   r  merely by rolling the rollers  3  across a surface. 
     OTHER EMBODIMENTS 
     In the embodiment described above, the multiple sets of display data D 1   r , D 2   r , D 3   r  are displayed such that they are lined up in the up-down direction. However, in a modified embodiment according to the present teachings, the multiple sets of display data D 1   r , D 2   r , D 3   r  may be displayed such that they are lined up in the left-right direction. In addition or in the alternative, the multiple sets of display data D 1   r , D 2   r , D 3   r  may be displayed such that they overlap. 
     In the embodiment described above, the first area AR 1 , the second area AR 2 , and the third area AR 3  are arranged in the up-down direction. However, in a modified embodiment according to the present teachings, the first area AR 1 , the second area AR 2 , and the third area AR 3  may be arranged in the left-right direction. 
     In the embodiment described above, the first area AR 1 , the second area AR 2 , and the third area AR 3  are different areas, i.e. different portions of the surface of the target material OB. However, in a modified embodiment according to the present teachings, the first area AR 1  and the second area AR 2  detected in multiple sensing operations may be the identical (same) area. That is, the user may use the embedded-object scanner device  1  to scan for embedded objects any number of times across the same area of the surface of the target material OB. The display device  8  may collectively display the multiple sets of display data generated in multiple sensing operations performed across the same area. 
     In the embodiment described above, the sensed data acquired by the first sensing operation and the sensed data acquired by the second sensing operation may be arithmetically processed, and the display-control part  105  may display, on the display device  8 , display data that shows the sensed data after it has been arithmetically processed. 
     In the embodiment described above, the guidance parts  2 S may include gradations. In addition or in the alternative, the guidance parts  2 S may include emitting (illumination) parts that emit, for example, laser light. 
     In the embodiment described above, the display device  8  scrolls the display data synchronized with the rotation of the rollers  3 . However, in a modified embodiment according to the present teachings, the display device  8  may scroll the display data based on a manual operation signal generated by the manual-operation device  7 , e.g., by pressing the left and right MOVE buttons  74 L,  74 R. 
     In the embodiment described above, the timing of the start of storage of the sensed data by the storage  107  and the timing of the end of storage of the sensed data by the storage  107  are determined based on the distance between the sensing surface  4 S of the sensing device  4  and the surface of the target material OB. However, in a modified embodiment according to the present teachings, the timing of the start of storage of the sensed data by the storage  107  and the timing of the end of storage of the sensed data by the storage  107  may be determined based on a manual operation signal generated by the manual-operation device  7 , e.g., by pressing START and STOP buttons (not shown) on the manual-operation device  7  or on the display device  8  (in case the display device  8  is a touchscreen). In addition or in the alternative, the timing of the start of storage of the sensed data by the storage  107  and the timing of the end of storage of the sensed data by the storage  107  may be determined based on the sensed data generated the rotation sensor  30 . For example, when the rotation of the rollers  3  has started in a sensing operation, the storage of the sensed data by the storage  107  may be started; and when the rotation of the rollers  3  in a sensing operation has ended, the storage of the sensed data by the storage  107  may be ended. 
     Additional aspects of the present teachings include, but are not limited to: 
     1. An embedded-object scanner device (wall scanner) comprising: 
     a housing; 
     a sensing device, which is housed in the housing and senses one or more embedded objects embedded in a target material; and 
     one or more illumination provided on the housing for illuminating at least a portion of the surface of the target material. 
     2. The embedded-object scanner device according to the above aspect 1, wherein: 
     the sensing device senses, while being moved in a left-right direction, the surface of the target material; and 
     the illumination device(s) include(s) one or more illumination-light-emitting parts that emit(s) illumination light in the left-right direction. 
     3. The embedded-object scanner device according to the above aspect 2, wherein: 
     the sensing device has a sensing surface that faces the target material; and 
     the position(s) of the illumination-light-emitting part(s) at least substantially coincide(s) with the position of the center of the sensing surface in an up-down direction. 
     4. The embedded-object scanner device according to any one of aspects 1-3, wherein: 
     the sensing device senses, while being moved in a left-right direction, the surface of the target material; and 
     the illumination device(s) include(s) one or more illumination-light-emitting parts that emit(s) illumination light in an up-down direction that is perpendicular to a (the) left-right direction. 
     5. The embedded-object scanner device according to the above aspect 4, wherein: 
     the sensing device has a sensing surface that faces the target material; and 
     the position(s) of the illumination-light-emitting part(s) at least substantially coincide(s) with the position of the center of the sensing surface in the left-right direction. 
     6. The embedded-object scanner device according to any one of the above aspects 1-5, wherein the illumination device(s) include(s) illumination-light-emitting parts respectively provided on each of a left side surface, a right side surface and an upper surface of the housing. 
     7. The embedded-object scanner device according to any one of the above aspects 1-6, wherein the sensing device has a sensing surface that faces the target material and is equipped with one or more indicator devices that indicate(s) the position of the sensing device. 
     8. The embedded-object scanner device according to the above aspect 7, wherein: 
     the sensing device senses, while being moved in a (the) left-right direction, the surface of the target material; and 
     the indicator device(s) indicate(s) the position of the center of the sensing surface in an up-down direction. 
     9. The embedded-object scanner device according to the above aspect 7 or 8, wherein: 
     the indicator device(s) comprise(s) a laser-light emitting part or laser-light emitting parts that emit(s) laser light in a (the) left-right direction; and 
     the position(s) of the laser-light emitting part(s) at least substantially coincide(s) with the position of the center of the sensing surface in a (the) up-down direction. 
     10. The embedded-object scanner device according to the above aspect 9, wherein: 
     the laser-light emitting part(s) is (are) provided on an outer surface of the housing; and 
     a distance between the center of the housing and the laser-light emitting part(s) is shorter than a distance between the center of the housing and an edge of the housing in the left-right direction. 
     11. The embedded-object scanner device according to any one of the above aspects 1-10, comprising: 
     a display device; 
     wherein: 
     the sensing device senses, while being moved in a (the) left-right direction, the surface of the target material; and 
     the display device displays one or more images of one or more embedded object(s) present between the center of the housing and edge parts of the housing in the left-right direction using a first display indicia, and displays the embedded object(s) present outward of the housing using a second display indicia. 
     12. The embedded-object scanner device according to the above aspect 11, wherein the display device: 
     displays a center line indicating the center of the housing in the left-right direction and edge lines that indicate the edges of the housing on both sides of the center line, and 
     displays the image(s) of the embedded object(s) between the edge lines using the first display indicia. 
     13. The embedded-object scanner device according to any one of the above aspects 1-12, comprising: 
     a manual-operation device that generates manual-operation signals for at least the illumination device(s). 
     14. The embedded-object scanner device according to the above aspect 13, wherein the manual-operation signals include a start signal for starting (turning ON) the illumination device(s) or a stop signal for stopping (turning OFF) the illumination device(s). 
     15. The embedded-object scanner device according to the above aspect 13 or 14, wherein the manual-operation signals include a light-intensity adjustment signal that adjusts the intensity of the light emitted from the illumination device(s). 
     16. The embedded-object scanner device according to any one of the above aspects 1-15, comprising a battery-mounting part, on which a battery for a power tool is mounted. 
     Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved embedded-object scanner devices (wall scanners) and methods of using the same. 
     Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings. 
     All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter. 
     Although some aspects of the present disclosure have been described in the context of a device, it is to be understood that these aspects also represent a description of a corresponding method, so that each block, part or component of a device, such as the control device (controller, processor)  10  is also understood as a corresponding method step or as a feature of a method step. In an analogous manner, aspects which have been described in the context of or as a method step also represent a description of a corresponding block or detail or feature of a corresponding device, such as the control device. 
     Depending on certain implementation requirements, exemplary embodiments of the control device  10  of the present disclosure may be implemented in hardware and/or in software. The implementation can be configured using a digital storage medium, for example one or more of a ROM, a PROM, an EPROM, an EEPROM or a flash memory, on which electronically readable control signals (program code) are stored, which interact or can interact with a programmable hardware component such that the respective method is performed. 
     A programmable hardware component can be formed by a processor, a computer processor (CPU=central processing unit), an application-specific integrated circuit (ASIC), an integrated circuit (IC), a computer, a system-on-a-chip (SOC), a programmable logic element, or a field programmable gate array (FGPA) including a microprocessor. 
     The digital storage medium can therefore be machine- or computer readable. Some exemplary embodiments thus comprise a data carrier or non-transient computer readable medium which includes electronically readable control signals that are capable of interacting with a programmable computer system or a programmable hardware component such that one of the methods described herein is performed. An exemplary embodiment is thus a data carrier (or a digital storage medium or a non-transient computer-readable medium) on which the program for performing one of the methods described herein is recorded. 
     In general, exemplary embodiments of the present disclosure, in particular the control device  10 , are implemented as a program, firmware, computer program, or computer program product including a program, or as data, wherein the program code or the data is operative to perform one of the methods when the program is executed by a processor or a programmable hardware component. The program code or the data can for example also be stored on a machine-readable carrier or data carrier. The program code or the data can be, among other things, source code, machine code, bytecode or another intermediate code. 
     A program according to an exemplary embodiment can implement one of the methods during its performing, for example, such that the program reads storage locations or writes one or more data elements into these storage locations, wherein switching operations or other operations are induced in transistor structures, in amplifier structures, or in other electrical, optical, magnetic components, or components based on another functional principle. Correspondingly, data, values, sensor values, or other program information can be captured, determined, or measured by reading a storage location. By reading one or more storage locations, a program can therefore capture, determine or measure sizes, values, variable, and other information, as well as cause, induce, or perform an action by writing in one or more storage locations, as well as control other apparatuses, machines, and components, and thus for example also perform complex processes using the device  1 . 
     Therefore, although some aspects of the control device have been identified as “parts” or “units” or “steps”, it is understood that such parts or units or steps need not be physically separate or distinct electrical components, but rather may be different blocks of program code that are executed by the same hardware component, e.g., one or more microprocessors. 
     One representative, non-limiting algorithm for operating the device  1 , which algorithm may be stored in and executed by the control device  10 , may include the steps of: (i) initiating a sensing operation by causing a sensing device  4  to emit sensing waves, (ii) receiving reflected sensing waves and outputting sensed data representative of the reflected sensing waves from the sensing device  4 , (iii) storing the sensed data in a memory (storage) location, (iv) repeating steps (i)-(iii) one or more times to collect and store additional sets of sensed data, e.g., from the same or different areas of a target material (OB), (v) processing the plurality of sets of sensed data, e.g., either at the time of capturing each set of sensed data or at the end of capturing all sets of sensed data, to identify one or more embedded objects in the plurality of sets of sensed data, (vi) optionally marking the embedded object(s) with first or second display indicia based on the location(s) of the embedded object(s), e.g., relative to the sensing device  4 , (vii) optionally compressing or shrinking the plurality of sets of sensed data in one spatial direction (e.g., an up-down direction, a left-right direction, etc.), (viii) correlating the plurality of sets of sensed data in the one spatial direction so that the plurality of sets of sensed data are displayable in an aligned arrangement in the one spatial direction, and (ix) displaying the plurality of sets of sensed data on a display screen in the aligned arrangement in the one spatial direction. 
     Optionally, the representative, non-limiting algorithm may further include: (x) receiving rotational sensor data from a rotation sensor  30  that senses rotational direction and speed of one or more rollers  3  of the device  1 , (xi) processing the rotational sensor data to determine the speed and direction of movement of the device  1  in the one spatial direction and (xii) scrolling the image of the displayed plurality of sets of sensed data in the aligned arrangement on the display screen in the determined direction of movement in the one spatial direction and in proportion to the detected rotational speed of the roller(s)  3 . 
     EXPLANATION OF THE REFERENCE NUMBERS 
     
         
           1  Embedded-object scanner device 
           2  Housing 
           2 A Upper surface 
           2 B Lower surface 
           2 C Left-side surface 
           2 D Right-side surface 
           2 E Front surface 
           2 F Rear surface 
           2 H Handle 
           2 S Guidance part 
           3  Roller 
           4  Sensing device 
           4 S Sensing surface 
           5  Illumination device 
           6  Indicator device 
           7  Manual-operation device 
           8  Display device 
           9  Battery-mounting part 
           9 G Guide rail 
           10  Control device 
           11  Battery 
           11 B Release button 
           11 G Slide rail 
           12  Notifying device 
           30  Rotation sensor 
           51  Illumination-light-emitting part 
           51 L Left illumination-light-emitting part 
           51 R Right illumination-light-emitting part 
           52  Illumination-light-emitting part 
           61  Laser-light emitting part 
           61 L Left laser-light-emitting part 
           61 R Right laser-light-emitting part 
           71  POWER button 
           72  SETTINGS button 
           73  MENU button 
           74  MOVE button 
           74 L MOVE LEFT button 
           74 R MOVE RIGHT button 
           75  ENTER button 
           81  Centerline 
           82  Edge-part line 
           82 L Left edge line 
           82 R Right edge line 
           83  Surface line 
           84  Depth line 
           85  Icon 
           86  First mark 
           87  Second mark 
           88  Icon 
           101  Sensing-control part 
           102  Sensed-data acquiring part 
           103  Illumination-control part 
           104  Indicator-control part 
           105  Display-control part 
           106  Notification-control part 
           107  Storage 
         AR 1  First area 
         AR 2  Second area 
         AR 3  Third area 
         AX Rotational axis 
         BU Image 
         D 1  Display data 
         D 1   r  Display data 
         D 2   r  Display data 
         D 3   r  Display data 
         Da Aggregated display data 
         Fa Selection frame 
         Fb Selection frame 
         Fc Selection frame 
         Fd Selection frame 
         GL Laser light 
         IL Illumination light 
         Ma Mark 
         Mb Mark 
         Mc Mark 
         OB Target Material 
         Pa Position 
         Pb Position 
         Pc Position 
         Pd Position 
         Pe Position 
         Pf Position