JP7301581B2 - Shape measuring device, radiotherapy system and shape measuring method - Google Patents

Description

TECHNICAL FIELD Embodiments of the present invention relate to a shape measuring device, a radiotherapy system, and a shape measuring method.

There is a technique for converting the distance to an object and the three-dimensional shape of the object into data by optical measurement. This technology is applied to implement, for example, a three-dimensional shape measuring apparatus (3D scanner) that optically measures (scans) the three-dimensional shape of an object and converts it into three-dimensional data. Based on the three-dimensional data, the shape of the object is displayed on a computer, or a model of the object is created. In addition, as part of radiotherapy planning, the presence or absence of interference between devices or between devices and a patient is determined based on three-dimensional data.

As a 3D scanner, for example, there is a pattern projection type 3D scanner that scans the three-dimensional shape of an object by projecting a pattern of infrared light onto the object. A pattern projection type 3D scanner is inexpensive and can be scanned at high speed. However, the pattern projection type 3D scanner has a problem of large measurement error compared to a 3D scanner that scans the three-dimensional shape of an object by irradiating the object with a laser beam.

Under these circumstances, there is a technique for correcting measurement errors by performing a 3D scan of an object whose distance and shape are known in order to reduce measurement errors. However, it is difficult to precisely position the 3D scanner at a defined position to acquire the measurement error. Also, the measurement error changes depending on, for example, the measurement distance. Acquiring the measurement error multiple times is not easy because it takes time and effort.

JP 2011-27594 A JP-A-7-88791 JP-A-10-115513

A problem to be solved by the invention is to easily correct a measurement error in non-contact shape measurement.

A shape measuring device according to an embodiment includes a first acquisition unit and a generation unit. a first acquisition unit configured to obtain first scan data relating to an outer shape of the correction plane obtained by optically scanning the correction plane from a direction oblique to a normal direction of the correction plane; Acquire the position information of the correction plane. The generator generates a measurement error distribution indicating a plurality of measurement errors regarding a plurality of measurement distances based on the first scan data and the position information of the correction plane.

FIG. 1 is a diagram showing an example of the configuration of a shape measuring system according to the first embodiment. 2A is a diagram for explaining an example of the appearance of the shape measuring apparatus of FIG. 1 and a measurement coordinate system; FIG. FIG. 2B is another diagram for explaining an example of the appearance of the shape measuring apparatus of FIG. 1 and the measurement coordinate system. FIG. 3 is a diagram for explaining an example of scan data obtained from the scanner in FIG. FIG. 4 is a flow chart showing an example of a series of flows related to error table generation according to the first embodiment. FIG. 5A is a diagram for explaining an example of a reference point area according to the first embodiment; FIG. 5B is another diagram for explaining an example of a reference point area according to the first embodiment; FIG. 6 is a diagram for explaining an example of the relationship between the scanner direction of the scanner and the acquisition range of the measurement error according to the first embodiment. FIG. 7 is a diagram for explaining an example of acquisition of measurement errors for each measurement point according to the first embodiment. FIG. 8 is a diagram for explaining an example of conversion from an error table for each measurement point to an error table for each reference point area according to the first embodiment. FIG. 9 is a diagram for explaining an example of interpolation of measurement errors for each reference point area according to the first embodiment. FIG. 10 is a flowchart showing an example of a series of flows related to scanning processing of a measurement object according to the first embodiment. 11A is a diagram for explaining another example of adjustment of the scanner direction according to the first embodiment; FIG. 11B is another diagram for explaining another example of the adjustment of the scanner direction according to the first embodiment; FIG. FIG. 12A is a diagram for explaining another example of obtaining a measurement error according to the first embodiment; FIG. 12B is a diagram for explaining another example of adjustment of the reference distance and the scanner direction according to the first embodiment; FIG. 13A is a diagram for explaining another example of adjustment of a reference distance and a scanner direction according to the first embodiment; FIG. 13B is another diagram for explaining another example of adjustment of the reference distance and the scanner direction according to the first embodiment; FIG. 14 is a diagram showing an example of the configuration of a radiotherapy system according to the second embodiment. 15 is a diagram showing an example of the configuration of the radiotherapy apparatus of FIG. 14. FIG. FIG. 16 is a flow chart showing an example of a series of flows related to error table generation according to the second embodiment. FIG. 17A is a diagram for explaining an example of movement of the treatment top plate according to the second embodiment; FIG. 17B is another diagram for explaining an example of the movement of the therapeutic tabletop according to the second embodiment.

[First embodiment]
A shape measuring apparatus, a radiotherapy system, and a shape measuring method according to the present embodiment will be described below with reference to the drawings. In the following description, constituent elements having the same or substantially the same functions as those described above with respect to the previous drawings are denoted by the same reference numerals, and duplicate description will be given only when necessary. Moreover, even when the same parts are shown, the dimensions and ratios may be different depending on the drawing.

A shape measuring apparatus according to the present embodiment is an apparatus that measures the three-dimensional shape of an object to be measured and generates a graphic model (3D model) representing the three-dimensional shape of the object to be measured. A shape measuring device is included in, for example, a radiotherapy system. At this time, the generated 3D model of the object to be measured is used, for example, for interference determination performed for radiotherapy or medical image diagnosis. The profilometer can also be used independently of the radiotherapy system. For example, the generated 3D model of the object to be measured is used for modeling, product inspection, and the like.

In addition, in the following description, the technology according to the present embodiment will be described by taking as an example the case of measuring the three-dimensional shape of the measurement target, but the present invention is not limited to this. The technique according to the present embodiment is applicable not only to the measurement of the three-dimensional shape of the measurement target, but also to the measurement of the two-dimensional shape of the measurement target, the distance to the measurement target, and the measurement of the position of the measurement target.

FIG. 1 is a diagram showing an example of the configuration of a shape measuring device 10 according to this embodiment. As shown in FIG. 1, the shape measuring device 10 has a processing circuit 11, a 3D scanner 131, a laser rangefinder 133, a memory 15, an input interface 17 and a display 19. The processing circuit 11, the 3D scanner 131, the laser rangefinder 133, the memory 15, the input interface 17, and the display 19 are communicably connected to each other via a bus or the like.

The processing circuit 11 controls the overall operation of the shape measuring device 10 . The processing circuit 11 executes a program related to shape measurement (hereinafter referred to as a shape measurement program) to perform calibration processing and measurement processing. The calibration process generates an error table for correcting measurement errors. In the measurement process, scan data obtained by scanning the object to be measured is corrected using an error table. The processing circuit 11 includes, as hardware resources, a processor such as a Central Processing Unit (CPU), a Micro Processing Unit (MPU), a Graphics Processing Unit (GPU), a Read Only Memory (ROM), a Random Access Memory (RAM) and the like. memory.

The processing circuit 11 executes a distance measurement data acquisition function 111, a scan data acquisition function 112, an error table generation function 113, an error correction function 114, a model generation function 115, and a display control function 116 by a shape measurement program.

In the ranging data acquisition function 111 , the processing circuit 11 acquires ranging data from the laser rangefinder 133 . The distance measurement data is a measurement result regarding the distance from the laser rangefinder 133 to the measurement object. The obtained distance measurement data is used by the error table generation function 113 in the calibration process. Here, the processing circuit 11 that implements the distance measurement data acquisition function 111 is an example of a reference distance acquisition unit.

In the scan data acquisition function 112 , the processing circuit 11 acquires scan data from the 3D scanner 131 . The scan data are the measurement results of the three-dimensional shape of the object to be measured. The acquired scan data is used by the error table generation function 113 in the calibration process, and is used by the error correction function 114 in the measurement process. Here, the processing circuit 11 that implements the scan data acquisition function 112 is an example of a first acquisition section and a second acquisition section.

In the error table generation function 113 , the processing circuit 11 acquires various information necessary for generating the error table, such as the effective viewing angle of the 3D scanner 131 from the memory 15 and the input interface 17 . The processing circuit 11 generates an error table based on the ranging data and scan data acquired by the ranging data acquisition function 111 and scan data acquisition function 112, respectively. The error table is data representing the spatial distribution of measurement errors (measurement error distribution) in the scanning range of the 3D scanner 131 . The generated error table is stored in the memory 15, for example. Here, the processing circuit 11 that implements the error table generation function 113 is an example of a generation unit.

In the error correction function 114 , the processing circuit 11 inputs scan data from the scan data acquisition function 112 . The processing circuit 11 refers to the error table in the memory 15 and corrects the scan data acquired by the scan data acquisition function 112 . The corrected scan data is used by model generation function 115 . Here, the processing circuit 11 that implements the error correction function 114 is an example of a correction unit.

In the model generation function 115 , the processing circuit 11 generates a 3D model based on the scan data corrected by the error correction function 114 . More specifically, the processing circuit 11 converts the corrected scan data (point cloud data) into polygon data. The processing circuit 11 generates a three-dimensional graphic model (3D model) of the object to be measured from the converted polygon data. The generated 3D model is stored in the memory 15, for example. Here, the processing circuit 11 that implements the model generation function 115 is an example of a model generation unit.

Note that the shape measuring device 10 may be a device that outputs corrected scan data (point cloud data) regarding the three-dimensional shape of the object to be measured. In other words, the generation of the 3D model may be performed outside the shape measuring device 10 .

In the display control function 116 , the processing circuit 11 displays various display information such as image data for displaying the generated 3D model and operation screen data on the display 19 .

The processing circuit 11 may be realized by an Application Specific Integrated Circuit (ASIC) or a Field Programmable Gate Array (FPGA). Processing circuitry 11 may also be implemented by other Complex Programmable Logic Devices (CPLDs) or Simple Programmable Logic Devices (SPLDs).

Note that the functions 111 to 116 are not limited to being realized by a single processing circuit. A plurality of independent processors may be combined to form a processing circuit, and the functions 111 to 116 may be realized by each processor executing a program.

The 3D scanner 131 measures the three-dimensional shape of the object to be measured in a non-contact manner. There are, for example, the following three types of non-contact three-dimensional shape measurement methods. In the first type, by irradiating a laser beam onto a measurement object and receiving the laser beam reflected or scattered by the measurement object, the time from projection to reception of the laser beam or the projected laser beam and the received laser beam are measured. A distance is calculated based on the phase difference with the laser beam. In the second type, a pattern of light such as infrared rays is projected onto an object to be measured, changes in the pattern are photographed by an optical camera, and the photographed image is subjected to image processing to calculate the unevenness of the object to be measured. In the third type, an object to be measured is simultaneously photographed by two optical cameras, and the image plane position of the object to be measured according to the parallax of the two optical cameras is used to calculate the unevenness of the object to be measured from the captured images. . It is assumed that the 3D scanner 131 according to the present embodiment digitizes the unevenness of the object to be measured in a non-contact manner using the second type of measurement method. The digitized three-dimensional shape of the object to be measured is, for example, point cloud data (hereinafter referred to as scan data) regarding a plurality of object points on the object to be measured. The generated scan data is supplied to the processing circuit 11 . Note that the 3D scanner 131 may be expressed as an example of the first acquisition unit and the second acquisition unit.

The light reflected or scattered by the object to be measured may be light irradiated to the object to be measured by the 3D scanner 131, or light irradiated to the object to be measured from a light source outside the 3D scanner 131. Alternatively, it may be natural light (environmental light). Further, the light is not limited to the infrared region, and may have a wavelength in the ultraviolet region or the visible region. Further, the light may be light of a single wavelength or light containing multiple wavelengths.

The laser rangefinder 133 measures the distance to the measurement object. The laser range finder 133 irradiates a laser beam onto the object to be measured and receives the laser beam reflected by the object to measure the distance to the object to be measured in a non-contact manner. The distance measurement method may be one using triangulation or may be one using Time of Flight (TOF). In addition, range finding may be performed using sound waves instead of laser light. Also, a measure may be used to measure the distance to the measurement target. In this case, the measurement results may be input to the input interface 17 . A measurement result (hereinafter referred to as distance measurement data) is supplied to the processing circuit 11 . Note that the laser rangefinder 133 may be expressed as an example of a reference distance acquisition unit.

The memory 15 is a storage device such as a RAM, a ROM, a Hard Disk Drive (HDD), a Solid State Drive (SSD), or an integrated circuit storage device that stores various information. For example, the memory 15 stores distance measurement data, an error table, a shape measurement program, and the like. The memory 15 may be, as hardware, a driving device or the like that reads and writes various information with a portable recording medium such as a CD-ROM drive, a DVD drive, and a flash memory.

The input interface 17 inputs various commands received from the user via the input device. A keyboard, a mouse, various switches, and the like can be used as input devices. The input interface 17 supplies output signals from the input device to the processing circuit 11 via the bus.

The display 19 displays various information. Display 19 may be, for example, a CRT display, liquid crystal display, organic EL display, LED display, plasma display, or any other display known in the art as appropriate. Also, instead of the display 19, a projector may be used.

Although the processing circuit 11, the 3D scanner 131, the laser rangefinder 133, the memory 15, the input interface 17, and the display 19 are integrally configured in the shape measuring apparatus 10 according to this embodiment, the present invention is not limited to this. The shape measuring device 10 may be implemented by a combination of multiple devices or parts thereof. For example, the 3D scanner 131 and the laser rangefinder 133 may be configured as separate devices. At this time, the 3D scanner 131 and the laser rangefinder 133 may be integrated. Also, the outputs of the 3D scanner 131 and the laser rangefinder 133 may each be supplied to the processing device via an external memory such as a USB memory.

Here, the measurement coordinate system of the shape measuring apparatus 10 according to this embodiment will be described with reference to the drawings. 2A and 2B are diagrams for explaining an example of the appearance of the shape measuring apparatus 10 of FIG. 1 and a measurement coordinate system. 2A and 2B show an example of the external appearance of the shape measuring device 10 viewed from the back and top, respectively, together with the coordinate axes of the measurement coordinate system.

In the following description, for the sake of simplicity, in the shape measuring device 10, the direction of scanning by the 3D scanner 131 and the direction of distance measurement by the laser rangefinder 133 are assumed to match. In the example shown in FIG. 2B, the direction in which scanning and ranging are performed by the shape measuring device 10 is indicated as the scanner direction SD.

As shown in FIG. 2A, a display 19 is provided on the rear surface of the housing 101 of the shape measuring device 10. As shown in FIG. Further, as shown in FIGS. 2A and 2B, the upper surface of the housing 101 is provided with an operation button for instructing the start of scanning. This operation button is included in the input interface 17 . Further, as shown in FIG. 2B, a light receiving optical system of the 3D scanner 131 is provided on the front surface of the housing 101 . The light incident on the light receiving optical system is incident on the light receiving surface of the light receiving element in the subsequent stage and converted into an electric signal. A light receiving element is, for example, a Charge-Coupled Device (CCD). The light-receiving element is, for example, a single-plate color CCD, but may be a three-plate color CCD. The light-receiving element is not limited to a CCD, and may be an image sensor such as a complementary metal-oxide semiconductor (CMOS) or other light-receiving element.

In the examples shown in FIGS. 2A and 2B, the origin of the measurement coordinate system is the position of the shape measuring device 10 (hereinafter referred to as scanner position). In other words, the origin of the measurement coordinate system is the position of the 3D scanner 131 and laser rangefinder 133 . Here, the scanner direction SD, that is, the direction from the rear surface to the entire surface of the 3D scanner 131 is the -Z direction. The scanner position is, for example, the center of the entrance pupil in the receiving optics of the 3D scanner 131 . Also, the Z axis is assumed to be the optical axis of the light receiving optical system of the 3D scanner 131, for example. The X-axis and the Y-axis are set in a plane orthogonal to each other and orthogonal to the Z-axis. The direction from the left side toward the right side toward the back of the 3D scanner 131 is the +X direction. The direction from the lower surface to the upper surface of the 3D scanner 131 is the +Y direction.

As the scanner position, the center of the light receiving element (imaging surface) of the 3D scanner 131 may be used, or the center of the housing 101 of the shape measuring apparatus 10 may be used. Also, the scanner position may be set on the housing 101 of the shape measuring apparatus 10 , such as the rear surface of the housing 101 of the shape measuring apparatus 10 . A display indicating the scanner position may be provided on the housing 101 of the shape measuring apparatus 10 or the like.

Next, scan data obtained from the 3D scanner 131 according to this embodiment will be described with reference to the drawings. FIG. 3 is a diagram for explaining an example of scan data obtained from the 3D scanner 131 in FIG.

In the example shown in FIG. 3, the scan data output by the 3D scanner 131 includes header information and point cloud data. Point cloud data includes, for example, the color and three-dimensional coordinates of each object point on the measurement object. The color includes, for example, the received light intensity of each color of R (red), G (green), and B (blue). Note that the scan data is, for example, in the ASCII text file format, but is not limited to this. The scan data may be in other file formats that can handle point cloud data.

In the example shown in FIG. 3, the header information includes the data format, the number of point data, and the data type of the point data. Also, the color information indicates the received light intensity of the R channel, G1 channel, G2 channel and B channel. Also, the position information is the position coordinates of each point in the measurement coordinate system of FIGS. 2A and 2B.

Note that the color information is appropriately changed according to the arrangement of pixels of the light receiving elements of the 3D scanner 131 and the like. Further, the color information may not be included in the point group data, or may further include A (transparency) depending on the light-receiving element.

An example of a series of flows relating to error table generation will be described in detail below with reference to the drawings. FIG. 4 is a flow chart showing an example of a series of flows related to error table generation according to the present embodiment.

Hereinafter, in the shape measuring apparatus 10 according to this embodiment, the 3D scanner 131 is assumed to be capable of measuring the three-dimensional shape of the measurement object within the scan range. Also, in the shape measuring apparatus 10 according to the present embodiment, it is assumed that measurement errors are corrected using an error table. Here, it is assumed that the error table is a measurement error distribution indicating measurement errors of each reference point area set within the scanning range of the 3D scanner 131 . Also, the scan range is defined by the effective distance and effective viewing angle (angle of view) of the 3D scanner 131 . The effective distance is assumed to be the distance from the scanner position in the scanner direction SD (-Z direction). The effective viewing angle is assumed to be the angle of the 3D scanner 131 opening in the scanner direction SD with the scanner position as the starting point on the ZX plane and the YZ plane.

Note that the scan range can be appropriately changed according to the imaging mode, imaging conditions, and the like. Therefore, the following flow may be performed for each shooting mode or shooting condition.

In step S<b>101 , a plurality of reference point areas are set within the scanning range of the 3D scanner 131 . 5A and 5B are diagrams for explaining an example of the reference point area DR according to this embodiment. FIG. 5A shows the ZX plane including the scanner position O within the scanning range SR of the shape measuring device 10. As shown in FIG. FIG. 5B shows a section 5B-5B of FIG. 5A.

First, the processing circuit 11 that implements the error table generation function 113 acquires the scan range SR of the 3D scanner 131 . In other words, processing circuitry 11 obtains the effective distance and the effective viewing angle. The scan range SR may be input to the input interface 17 by the user, or may be preset and stored in the memory 15 . In the example shown in FIGS. 5A and 5B, the effective distance is 0.5-2.0 m. Also, the effective viewing angle is 54° on the ZX plane (X-axis direction) and the YZ plane (Y-axis direction). For example, when the effective viewing angles in the X-axis direction and the Y-axis direction of the 3D scanner 131 are 54°, respectively, the scanning distance (measurement distance), the width of the effective visual field, and the height of the effective visual field are approximately the same length.

Next, the processing circuit 11 that implements the error table generation function 113 acquires the number of divisions. The division number may be input to the input interface 17 by the user, or may be preset and stored in the memory 15 . In the example shown in FIGS. 5A and 5B, the number of divisions in the X, Y and Z directions is 10 each.

Thereafter, the processing circuit 11 that implements the error table generation function 113 divides the scan range SR of the 3D scanner 131 into equal intervals according to the number of divisions in each of the X, Y, and Z directions. A point dividing the scanning range in each direction is hereinafter referred to as a reference point DP. The processing circuit 11 sets a hexahedron defined by eight reference points DP as a reference point area DR. Thus, a plurality of reference point areas DR are set in the scanner direction SD of the 3D scanner 131 . In the example shown in FIGS. 5A and 5B, since the scanning range SR is divided into 10 in each of the X, Y, and Z directions, 1331 reference points DP and 1000 reference point areas DR are set. ing.

Note that the intervals between the reference points DP are not limited to equal intervals. For example, the distance between the reference points DP may be set finer in the X-axis direction or the Y-axis direction as they move away from the Z-axis, or may be set finer in the Z-axis direction as they move away from the scanner position O. Also, the interval between the reference points DP may be different for each direction.

Although the case where the reference point area DR is set by the processing circuit 11 that implements the error table generation function 113 has been described as an example, the present invention is not limited to this. The reference point area DR may be preset and stored in the memory 15 .

In step S102, the shape measuring device 10 is installed. FIG. 6 is a diagram for explaining an example of the relationship between the scanner direction SD of the 3D scanner 131 and the measurement error acquisition range according to the present embodiment. As shown in FIG. 6, the shape measuring apparatus 10 is installed at a position (hereinafter referred to as the reference position) at a predetermined distance (hereinafter referred to as the reference distance d) from the correction plane CP. That is, the reference distance d is the distance between the shape measuring device 10 and the correction plane CP, as shown in FIG. In other words, the reference distance d is the distance from the scanner position O to the correction plane CP in the normal direction of the correction plane CP. The shape measuring device 10 is installed at the reference position by measuring the reference distance d with the laser rangefinder 133, for example. The reference distance d is, for example, 0.5 m. The reference position is determined according to the scanning range SR of the 3D scanner 131, for example. Determination of the reference position will be described later. The shape measuring device 10 may be manually installed by an operator or the like, or may be installed by a movable mechanical arm or the like. Here, the reference distance d is an example of position information of the correction plane CP.

Further, the shape measuring device 10 is adjusted so as to face the correcting plane CP. At this time, the scanner direction SD of the shape measuring device 10 is the first scanner direction SD1. That is, the first scanner direction SD1 is orthogonal to the correction plane CP. For this reason, it is assumed that the shape measuring device 10 installed at the reference position is rotatably fixed in the horizontal direction by, for example, a tripod. In other words, the scanner direction SD of the shape measuring device 10 is rotatable with respect to the horizontal direction. The position of the shape measuring device 10 may be adjusted manually by an operator or the like, or may be adjusted by a movable mechanical arm or the like.

The correction plane CP is a measurement target for obtaining scan data for correction. The correction plane CP is, for example, a structure having a uniform plane. The correction plane CP is desirably larger than the scanning range of the shape measuring device 10, such as 2 m×2 m or more. Moreover, it is desirable that the correction plane CP has a high degree of flatness. In the following description, a case where a wall surface inside a building is used as the correction plane CP will be described as an example.

In step S103, the scanner direction SD of the shape measuring device 10 is rotated to the reference angle θ. At this time, as shown in FIG. 6, the scanner direction SD of the shape measuring device 10 is the second scanner direction SD2. That is, the reference angle θ can also be expressed as an angle formed by the first scanner direction SD1 and the second scanner direction SD2. The shape measuring device 10 is rotated to the reference angle θ by using a goniometer, for example. The reference angle θ is, for example, 50°. The reference angle θ is appropriately set according to the scanning range SR of the 3D scanner 131 and the number of divisions. The shape measuring apparatus 10 may be manually rotated by an operator or the like, or may be rotated by a movable mechanical arm or the like.

Here, setting of the reference distance d and the reference angle θ will be described in more detail. In the following description, for the sake of simplicity, the scan range SR on the ZX plane will be taken as an example. In the example shown in FIG. 6, the distance V1 is the distance from the scanner position O to the closest point to the scanner position O among the points on the correction plane CP within the scanning range on the ZX plane. Similarly, the distance V2 is the distance from the scanner position O to the farthest point from the scanner position O among the points on the correction plane CP within the scanning range on the ZX plane. At this time, the distance V1 and the distance V2 are expressed as follows. Here, it is assumed that the effective viewing angle of the 3D scanner 131 is 54°.

For example, if the distance V1 is 0.5 m and the reference angle θ is 50°, the reference distance d and the distance V2 are 0.46 m and 2.04 m, respectively, from equations (1) and (2). That is, when the reference distance d and the reference angle θ are set to 0.46 m and 50°, respectively, the measurement error can be obtained for the distance of 0.5 to 2.0 m from the scanner position O in the scanning range on the ZX plane. become. In other words, in the correction scan according to this embodiment, it is possible to obtain a plurality of measurement errors related to a plurality of measurement distances. Thus, the reference distance d and the reference angle θ are set according to the scan range SR of the 3D scanner 131, for example.

In step S104, the processing circuit 11 that implements the scan data acquisition function 112 acquires scan data for correction. The scan data for correction is scan data obtained by scanning the correction plane CP as the measurement target in the second scanner direction SD2. In other words, the scan data for correction is scan data relating to the outer shape of the plane CP for correction. Here, the scan data for correction is an example of the first scan data. The acquired scan data for correction is stored in the memory 15 .

In step S105, the processing circuit 11 that implements the error table generation function 113 calculates measurement errors for each measurement point. FIG. 7 is a diagram for explaining an example of acquisition of measurement errors for each measurement point according to the present embodiment. In the following description, for the sake of simplicity, the measurement point P1 on the ZX plane is taken as an example.

The intersection of the correction plane CP and the perpendicular line from the scanner position O to the correction plane CP, that is, the point P0 can be expressed as a position obtained by rotating the point P0' by -θ on the ZX plane. Here, in the measurement coordinate system of the shape measuring device 10, the spatial coordinates of the scanner position O and the point P0' are (0, 0, 0) and (0, 0, d), respectively. Since the Y coordinate does not change, consider rotating the point P0' by -θ in the ZX coordinate system. The coordinates of the point P0' in the ZX coordinate system are (0, d). Assuming that the coordinates of the point P0 in the ZX coordinate system are (Vx, Vz), Vx and Vz are expressed as follows.

That is, the spatial coordinates of the point P0 in the measurement coordinate system are expressed as (d sin θ, 0, d cos θ). Also, the normal vector of the correction plane CP is a vector directed from the point P0 to the scanner position O. FIG. Therefore, the correction plane CP is represented by the following plane equation.

Further, if the spatial coordinates of the measurement point P1 of the scan data for correction in the measurement coordinate system are (Sx, Sy, Sz), the equation of a straight line passing through the measurement point P1 and the scanner position O can be expressed using the parameter t as , expressed as follows:

Assuming that the original position of the measurement point P1 is a point P2, the point P2 is the intersection of the plane of the formula (5) and the straight line of the formula (6). Therefore, from equations (5) and (6), the spatial coordinates (x, y, z) of point P2 in the measurement coordinate system are expressed as follows.

The processing circuit 11 calculates the distance ER between the point P2 thus calculated and the measurement point P1 as the measurement error of the measurement point P1. Also, the processing circuit 11 similarly calculates the measurement error for each measurement point. A plurality of measurement errors relating to a plurality of measurement points are stored in the memory 15 as an error table for each measurement point. For example, when the resolution of the 3D scanner 131 is 640×480, an error table for each measurement point storing 307200 measurement errors is generated at this point.

For example, due to individual differences of the 3D scanner 131 and imaging conditions, the positions of measurement points may differ between scan data. FIG. 8 is a diagram for explaining an example of conversion from an error table for each measurement point to an error table for each reference point area DR according to the present embodiment. That is, as shown in FIG. 8, the position of the measurement point P1 and the position of the reference point DP may differ. Therefore, in steps S106 to S109, the processing circuit 11 that implements the error table generation function 113 converts the measurement error for each measurement point calculated as described above into an error table for each reference point region DR. . In other words, the processing circuit 11 converts the error table for each measurement point into an error table for each reference point area DR.

In step S106, the processing circuit 11 that implements the error table generation function 113 identifies the reference point region DR including the measurement point P1.

In step S107, the processing circuit 11 that implements the error table generation function 113 calculates measurement errors with respect to the reference point region DR including the measurement point P1. Specifically, the processing circuit 11 tabulates the measurement error regarding the measurement point P1 as the measurement error in the reference point area DR.

Note that when a plurality of measurement points P1 exist in one reference point region DR, the processing circuit 11 calculates the average value of a plurality of measurement errors relating to the plurality of measurement points P1 as the measurement error in the reference point region DR. table as

It should be noted that there may be a case where there is a large variation in the plurality of measurement errors regarding the plurality of measurement points P1. In such a case, processing circuitry 11 calculates the variance of multiple measurement errors for multiple measurement points P1. When the calculated variance value is equal to or greater than the predetermined threshold value, the processing circuit 11 determines that the measurement error cannot be corrected for the reference point region DR, and in this step calculates the measurement error for the reference point region DR. It doesn't have to be. Further, when the calculated variance value is equal to or greater than a predetermined threshold value, the processing circuit 11 may exclude the reference point region DR from the scan data to be measured.

In step S108, the processing circuit 11 that implements the error table generation function 113 interpolates measurement errors with respect to the reference point area DR that does not include the measurement point P1. FIG. 9 is a diagram for explaining an example of interpolation of measurement errors for each reference point region DR according to this embodiment. As shown in FIG. 9, the plurality of reference point areas DR include reference point areas DR2 in which the measurement point P1 does not exist and reference point areas DR4 in which the measurement error is not calculated as described above. Therefore, the processing circuit 11 uses the measurement error calculated for the reference point area DR including the measurement point P1 to interpolate the measurement error for the reference point area DR in which the measurement error is not calculated. The measurement error varies, for example, depending on the distance to the object to be measured. Therefore, the processing circuit 11 uses the measurement error of another reference point area DR having the same distance from the scanner position O as the measurement error of the reference point area DR whose measurement error is not calculated. In the example shown in FIG. 9, the measurement error of the reference point region DR4 is interpolated by the measurement error of the reference point region DR1. Similarly, the measurement error for the reference point region DR3 interpolates the measurement error for the reference point region DR2.

Note that when the measurement error is calculated for a plurality of reference point regions DR among the other reference point regions DR having the same distance from the scanner position O, for example, the average of the measurement errors for the plurality of reference point regions DR value should be used.

In step S109, the processing circuit 11 that implements the error table generation function 113 outputs an error table. The output error table is stored in memory 15 .

An example of a series of flows relating to error table generation will be described in detail below with reference to the drawings. FIG. 10 is a flow chart showing an example of a series of flows relating to scanning processing of a measurement object according to this embodiment.

In step S201, the processing circuit 11 that implements the scan data acquisition function 112 acquires scan data obtained by scanning the object to be measured. Scan data obtained by scanning the object to be measured is scan data related to the outer shape of the object to be measured. Here, the scan data obtained by scanning the object to be measured is an example of the second scan data. Note that the scan data acquired in this step includes a plurality of scan data obtained by scanning the measurement object at a plurality of angles.

In step S202, the processing circuit 11 that implements the error correction function 114 identifies which reference point region DR includes each measurement point of the scan data to be measured.

In step S203, the processing circuit 11 that implements the error correction function 114 refers to the error table and acquires the measurement error regarding the specified reference point region DR. The processing circuit 11 uses the acquired measurement error to correct the measurement value of each measurement point. For example, if the measurement error for the identified reference point region DR is -2.3 cm, the position on the straight line that connects the actual measurement point and the scanner position O is 2.3 cm from the actual measurement point in the direction away from the scanner position O. , is the position of the corrected measurement point. In this manner, processing circuitry 11 produces corrected scan data. The corrected scan data are stored in the memory 15, for example.

If the actual measurement point is included in the reference point region DR that cannot be corrected, the actual measurement point is treated as non-existent.

In step S204, the processing circuit 11 that implements the model generation function 115 synthesizes the corrected scan data to generate a three-dimensional model of the measurement target (target model). The generated three-dimensional model of the object to be measured is stored in the memory 15, for example.

In step S205, the processing circuit 11 that implements the display control function 116 generates image data for display from the three-dimensional model of the object to be measured. The generated display image data is displayed on the display 19 .

Note that the scan for correction may be performed multiple times. A plurality of scans of the correction plane CP are performed with respect to, for example, a plurality of scanner directions SD and a plurality of reference distances d. For example, after scanning with the reference angle θ of 50° as described above, scanning is performed with the reference angle θ of −50°. At this time, the same range of the correction plane CP may be scanned multiple times, or different ranges may be scanned. When the scanning for correction is performed a plurality of times, the error table may be a table of values obtained by averaging the measurement errors within the same reference point area DR by the number of times of scanning.

In addition, in the scan for correction, the scanner direction SD (reference angle θ) may be adjusted based on the distance measurement result of the laser rangefinder 133, for example. 11A and 11B are diagrams for explaining another example of adjustment of the scanner direction SD according to this embodiment. As shown in FIGS. 11A and 11B, for example, when the reference distance d is 0.5 m and the reference angle θ is 30° and 45°, the distance measurement result of the laser rangefinder 133 is √2/ It is sufficient if the shape measuring device 10 is rotated with respect to the horizontal direction to indicate 2m and 1/√3m.

Acquisition of the measurement error for the measurement point is not limited to the calculation method. FIG. 12A is a diagram for explaining another example of obtaining a measurement error according to this embodiment. As shown in FIG. 12A, a reference line RL is drawn in advance on the correction plane CP at a position at a predetermined distance from the scanner position O in the predetermined scanner direction SD. In this case, for points on the reference line RL, the distance from the scanner position O is known. Therefore, the measurement error for a measurement point can be calculated by comparing the measurement for a point on the reference line RL with a known distance.

Note that the reference distance d and the scanner direction SD may be adjusted, for example, by drawing a reference line on the correction plane CP. FIG. 12B is a diagram for explaining another example of adjustment of the reference distance d and the scanner direction SD according to this embodiment. Assume that the reference line RL is drawn on the correction plane CP as shown in FIG. 12A. In other words, the reference line RL is drawn on the correction plane CP. At this time, the shape measuring apparatus 10 includes an imaging unit that captures light from a subject and outputs the image data. The imaging unit has an imaging optical system and an imaging device. The light incident on the imaging optical system is incident on the imaging surface of the imaging element in the subsequent stage and converted into an electrical signal. The imaging device is, for example, an image sensor such as CCD or CMOS. Note that the light receiving optical system and light receiving element of the 3D scanner 131 may be used as the image capturing optical system and image capturing element. At this time, the 3D scanner 131 can be expressed as an example of an imaging unit. The processing circuit 11 that implements the display control function 116 superimposes a guide image I10 on the live view display on the display 19, as shown in FIG. 12B. The guide image I10 includes a guide reference line IL. The guiding reference line IL corresponds to the shape of the reference line RL viewed obliquely with respect to the normal direction of the correction plane CP. In this case, the user may adjust the reference distance d and the scanner direction SD on the display 19 so that the live view display reference line RL and the superimposed guide reference line IL match. The reference line RL may be represented by a concave structure or a convex structure provided on the correction plane CP. Here, the processing circuit 11 that implements the display control function 116 is an example of a display unit. Note that the display 19 may be expressed as an example of a display unit. The reference line RL is an example of a reference figure. The guide reference line IL is an example of a guide figure.

Note that the reference distance d and the scanner direction SD are not limited to the reference line described above, and may be adjusted by, for example, drawing a reference figure on the correction plane CP. 13A and 13B are diagrams for explaining another example of adjustment of the reference distance d and the scanner direction SD according to this embodiment. As shown in FIG. 13A, it is assumed that a reference figure RG is drawn in advance on a correction plane CP at a position a predetermined distance from the scanner position O in a predetermined scanner direction SD. In other words, the reference graphic RG is drawn on the correction plane CP. At this time, the processing circuit 11 that implements the display control function 116 superimposes a guide image I20 on the live view display on the display 19, as shown in FIG. 13B. The guide image I20 includes a guide reference graphic IG. The guide reference figure IG corresponds to the shape of the reference figure RG viewed obliquely with respect to the normal direction of the correction plane CP. In this case, the user may adjust the reference distance d and the scanner direction SD on the display 19 so that the live-view-displayed reference graphic RG and the superimposed guide reference graphic IG match. The reference figure RG may be represented by a concave structure or a convex structure provided on the correction plane CP. Here, the reference graphic RG is an example of a reference graphic. Further, the guide reference figure IG is an example of a guide figure.

Note that the reference line RL and the reference graphic RG are not limited to being drawn on the correction plane CP, and may be projected onto the correction plane CP by a liquid crystal projector or the like. In this case, the shape measuring device 10 may include the liquid crystal projector.

In the above-described embodiment, the case where the wall surface of the structure is used as the correction plane CP has been described as an example, but the present invention is not limited to this. For example, a floor surface may be used as the correction plane CP. Further, the correction plane CP may be, for example, a portable screen or the like for projecting a screen or the like from a liquid crystal projector. In this case, the reference distance d and the scanner direction SD may be adjusted not only by the 3D scanner 131 but also by moving or rotating the screen.

In addition, although the portable shape measuring device 10 has been described as an example in the above-described embodiment, the present invention is not limited to this. For example, the shape measuring device 10 may be fixed to a radiotherapy device or the like in a radiotherapy system so that the scanner position O is uniquely determined. Alternatively, it may be fixed to a jig or the like designed so that the distance from the correction plane CP is uniquely determined. Moreover, the reference distance d may be measured outside the shape measuring device 10 and the distance measurement result may be input to the shape measuring device 10 . In this way, if the reference distance d can be treated as a known value, the shape measuring device 10 does not have to have the laser rangefinder 133 .

In the above-described embodiment, by rotating the scanner direction SD around the Y-axis (horizontal direction) from the normal direction of the correction plane CP, shape measurement is performed to obtain a plurality of measurement errors related to a plurality of distances at once. Although the device 10 has been described as an example, the scanner direction SD may be rotated about the X-axis or the Z-axis. Also, the scanner direction SD may be rotated around two or more of the X, Y, and Z axes.

As described above, the correction scan according to the present embodiment is performed by scanning the correction plane CP from a direction oblique to the normal direction of the correction plane CP. The scan data for correction acquired in this manner is point cloud data relating to measurement points at a plurality of scan distances (measurement distances). That is, according to the technique according to the present embodiment, it is possible to obtain a plurality of measurement errors related to a plurality of measurement distances by performing at least one correction scan. In other words, according to the technique according to the present embodiment, since it is not necessary to arrange the shape measuring device 10 while measuring the reference distance d for each measurement distance, it is possible to easily acquire the scan data for correction. There is If the scan data for correction can be easily obtained, the work time required for the correction work of the shape measuring device 10 can be shortened.

Note that the correction scan for scanning the correction plane CP from a direction oblique to the normal direction of the correction plane CP is limited to the case where the scanner direction SD is inclined with respect to the normal direction of the correction plane CP. do not have. With respect to at least two measurement points included in scan data obtained by scanning for correction, the directions of straight lines passing through the two measurement points and the scanner position O each have an inclination with respect to the normal direction of the correction plane CP. It's fine if you do. That is, according to the technique according to the present embodiment, even when the scanner direction SD and the normal direction of the correction plane CP match, as in the above-described embodiment, one correction is performed. A plurality of measurement errors for a plurality of measured distances can be obtained by scanning.

Also, the measurement error distribution according to this embodiment is a plurality of measurement errors related to a plurality of measurement distances. More specifically, the measurement error distribution is generated as an error table showing the calculated measurement error for each reference point area. Further, the scan data relating to the measurement object is corrected by referring to the error table according to the measurement distance of each measurement point. More specifically, the scan data regarding the object to be measured is corrected by the measurement error according to the measurement distance of each measurement point. With this configuration, even if the measurement points differ depending on the imaging conditions and the 3D scanner 131, the scan data regarding the measurement target can be corrected appropriately.

A plurality of correction scans performed from different oblique directions are assumed to be modeled by synthesizing a plurality of scan data obtained by scanning while changing the scan angle (scanner direction SD). By generating an error table from a plurality of scan data for correction obtained by scanning in a plurality of scanner directions SD in this way, an improvement in accuracy when combining scan data to be measured can be expected.

[Second embodiment]
A shape measuring apparatus, a radiotherapy system, and a shape measuring method according to the present embodiment will be described below with reference to the drawings. Here, differences from the first embodiment will be mainly described. In the following description, constituent elements having the same or substantially the same functions as those of the first embodiment are denoted by the same reference numerals, and repeated description will be made only when necessary.

FIG. 14 is a diagram showing an example of the configuration of the radiotherapy system 1 according to this embodiment. As shown in FIG. 14 , the radiotherapy system 1 has a 3D scanner 131 , a laser rangefinder 133 , an interference determination device 30 , a treatment planning imaging device 50 , a treatment planning device 70 and a radiotherapy device 90 . The 3D scanner 131, the laser rangefinder 133, the interference determination device 30, the treatment planning imaging device 50, the treatment planning device 70, and the radiotherapy device 90 are communicably connected to each other via a network or the like.

The shape measuring device 10 according to this embodiment includes, for example, a 3D scanner 131, a laser rangefinder 133, and an interference determination device 30. Note that the 3D scanner 131, the laser rangefinder 133, and the interference determination device 30 may be integrally configured, or may be configured as different devices.

The 3D scanner 131 according to this embodiment is a portable measuring device that optically measures the three-dimensional shape of a measurement target. Scan data obtained by the 3D scanner 131 is supplied to the interference determination device 30 . The object to be measured is set as an object for which a graphic model to be used for interference judgment by the interference judgment device 30 is generated. Typically, it has a different form for each radiotherapy or medical image diagnosis, and the form differs from the standard graphic model prepared in advance. Specifically, the measurement target may be a patient undergoing radiotherapy or medical image diagnosis, or a combination of a patient undergoing radiotherapy or medical image diagnosis and a fixture for fixing the patient to the bed.

The interference determination device 30 is a computer including a processor such as a CPU or GPU, a memory such as ROM or RAM, a display device, an input interface, and a communication interface. Similar to the processing circuit 11 of the shape measuring device 10 according to the first embodiment, the processing circuit of the interference determination device 30 has a distance measurement data acquisition function 111, a scan data acquisition function 112, and an error table generation function by a shape measurement program. 113, the error correction function 114, the model generation function 115 and the display control function 116 are executed. Further, the interference determination device 30 determines interference between devices of the treatment planning imaging device 50 or the radiation therapy device 90 or between the device and the patient. The processing circuit of the interference determination device 30 utilizes the three-dimensional graphic model of the measurement object scanned by the 3D scanner 131 to further perform an interference determination function of determining interference through simulation. Here, the processing circuit of the interference determination device 30 that implements the interference determination function is an example of an interference determination unit.

The treatment planning imaging apparatus 50 is a medical image diagnostic apparatus that generates medical images used for radiotherapy planning (hereinafter referred to as treatment planning images). The treatment planning image capturing device 50 may be any medical image diagnostic device that can visualize the patient's body surface. As such a treatment planning imaging device 50, for example, an X-ray computed tomography device, a cone-beam CT device, a magnetic resonance imaging device, an ultrasonic diagnostic device, or the like is used.

The treatment planning apparatus 70 is a computer including a processor such as a CPU or GPU, a memory such as a ROM or RAM, a display device, an input interface, and a communication interface. The treatment planning apparatus 70 receives treatment planning images directly from the treatment planning imaging apparatus 50 or via a medical image archiving and communication system (PACS) or the like. The treatment planning device 70 utilizes the treatment planning images to create a treatment plan for the patient. A treatment plan includes a treatment plan image and radiotherapy conditions. Radiotherapy conditions include various conditions such as tumor position, number of radiation irradiation directions, radiation irradiation angle, radiation intensity, collimator opening degree, wedge filter, and the like. The treatment plan is transmitted to radiation therapy apparatus 90 .

FIG. 15 is a diagram showing an example of the configuration of the radiotherapy apparatus 90 of FIG. 14. As shown in FIG. The radiotherapy apparatus 90, as shown in FIG. 15, has a treatment platform 91 (gantry), a treatment bed 94, and a console. The therapeutic platform 91 has a holding device 92 and an irradiation head 93 rotatably provided on the holding device 92 about a rotation axis. The irradiation head 93 is equipped with an acceleration tube for accelerating electrons generated by an electron gun or the like, and a metal target against which the electrons accelerated by the acceleration tube collide. X-rays, which are radiation, are generated by the collision of electrons with the metal target. The irradiation head 93 irradiates radiation according to the radiotherapy conditions included in the treatment plan identified by the treatment planning device 70 . The point where the beam axis of radiation from the irradiation head 93 and the axis of rotation intersect is spatially immobile and called the isocenter. The therapeutic bed 94 has a base 95 provided on the floor and a therapeutic top plate 96 on which the patient is placed. The therapeutic top plate 96 is movably supported by the base 95 . The therapeutic top plate 96 has a planar shape like the imaging top plate. The treatment platform 91, the treatment couch 94 and the patient are aligned such that the patient treatment site coincides with the isocenter. In addition, as shown in FIG. 15, the treatment top plate 96 according to this embodiment is used as a correction plane CP.

An example of a series of flows relating to error table generation will be described in detail below with reference to the drawings. FIG. 16 is a flow chart showing an example of a series of flows related to error table generation according to this embodiment. 17A and 17B are diagrams for explaining an example of the movement of the therapeutic top plate 96 according to this embodiment. FIG. 17A shows an example of the arrangement of the treatment bed 94 and the 3D scanner 131 viewed from the treatment platform 91 side in FIG. 15 . The following description will be made while comparing with an example of a series of flow relating to error table generation according to the first embodiment shown in FIG.

Steps S301 through S304 are the same as steps S101 through S104 in FIG. 4, respectively. The correction plane CP according to this embodiment is the treatment top plate 96 of the radiotherapy apparatus 90 . Also, the adjustment of the reference distance d may be realized by moving the treatment top plate 96 .

In step S305, it is determined whether or not scanning of a predetermined range has been completed. As shown in FIG. 17A, depending on the scan range SR of the 3D scanner 131, the size of the treatment top plate 96 may not be sufficient for the correction plane CP. For this reason, in the present embodiment, the scanning data for correction is collected while moving the treatment table 96 until the scanning for correction is completed with respect to the range (predetermined range) of the size required for the correction plane CP. to collect. If it is determined that the scanning of the predetermined range has been completed, the process proceeds to step S307; otherwise, the process proceeds to step S306.

In step S306, the treatment top plate 96 is moved. For example, in the example shown in FIG. 17A, the treatment top plate 96 is moved in directions BD1 and BD2 in the scan range SR. After the therapeutic top plate 96 is moved, the process returns to step S304. Thereafter, in step S304, a correction scan is performed on the moved treatment table 96. FIG.

It should be noted that the movement of the top plate 96 for treatment is not limited to the X-axis direction, and may be further moved in the Z-axis direction according to a predetermined range, a measurement range for each scan, and the like. Note that the predetermined range, the measurement range for each scan, and the like may be set in advance and stored in the memory 15, for example. Note that the measurement range for each scan may be calculated based on the scan range SR and the reference distance d.

In addition, as shown in FIG. 17B, the treatment top plate 96 is moved not only in the Z-axis and X-axis directions in the coordinate system of the radiotherapy apparatus 90 but also in the Y-axis direction (the direction BD3 in the example shown in FIG. 17B). may be Even in this case, it is possible to acquire the measurement error for each distance to the measurement point within the required range by scanning multiple times.

The movement of the treatment top plate 96 may be controlled by the user in the radiotherapy apparatus 90 or may be controlled by the processing circuit of the interference determination apparatus 30 according to the scan range SR or the like.

In step S307, it is determined whether scanning has been completed with respect to all the reference angles θ. If it is determined that scanning has been completed with respect to all the reference angles θ, the process proceeds to step S308; otherwise, the process returns to step S303.

Steps S308 to S312 are the same as steps S105 to S109 in FIG. 4, respectively.

As described above, in the correction scan according to the present embodiment, the treatment top plate 96 is used as the correction plane CP. Further, when the treatment top plate 96 is not included in the entire scanning range (effective viewing angle) of one scan, in the scanning for correction according to the present embodiment, scan data for correction is acquired for the entire effective viewing angle. Treatment table 96 is moved so that That is, according to the technique according to the present embodiment, it is possible to acquire a plurality of scan data relating to the positions of the plurality of therapeutic top plates 96 as the scan data for correction. In other words, in the correction scan according to the present embodiment, when the size of the range that can be used as the correction plane CP of the treatment top plate 96 is smaller than the size required as the correction plane CP, the treatment The top plate 96 is moved. This makes it possible to obtain a plurality of measurement errors related to a plurality of measurement distances, as in the case of using the correction plane CP that includes the entire scanning range of one scan.

According to at least one embodiment described above, it is possible to easily correct measurement errors in non-contact shape measurement.

The term "processor" used in the above description means circuits such as CPU, GPU, Application Specific Integrated Circuit (ASIC), and Programmable Logic Device (PLD). PLDs include Simple Programmable Logic Devices (SPLDs), Complex Programmable Logic Devices (CPLDs), and Field Programmable Gate Arrays (FPGAs). The processor realizes its functions by reading and executing the programs stored in the memory circuit. The memory circuit storing the program is a computer-readable non-transitory recording medium. It should be noted that instead of storing the program in the memory circuit, the program may be directly installed in the circuit of the processor. In this case, the processor realizes its function by reading and executing the program embedded in the circuit. Also, functions corresponding to the program may be realized by combining logic circuits instead of executing the program. Note that each processor of the present embodiment is not limited to being configured as a single circuit for each processor, and may be configured as one processor by combining a plurality of independent circuits to realize its function. good. Furthermore, a plurality of components in FIGS. 1 and 14 may be integrated into one processor to realize its functions.

While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, as well as the scope of the invention described in the claims and equivalents thereof.

1... radiotherapy system,
10 ... Shape measuring device,
11 ... processing circuit,
15... memory,
17 ... input interface,
19 ... display (display unit),
30... Interference determination device (interference determination unit),
50... treatment plan imaging device,
70 ... Treatment planning device,
90... Radiotherapy device,
91 ... therapeutic stand,
92 ... holding device,
93 ... irradiation head,
94 ... treatment bed,
95 ... base,
96... Top plate for treatment,
101 ... housing,
111 ... Ranging data acquisition function (reference distance acquisition unit),
112 ... Scan data acquisition function (first acquisition unit, second acquisition unit),
113 ... error table generation function (generation unit),
114 ... error correction function (correction unit),
115 ... model generation function (model generation unit),
116... Display control function (display unit),
131 ... 3D scanner (first acquisition unit, second acquisition unit, imaging unit),
133... Laser rangefinder (reference distance acquisition unit).

Claims (8)

first scan data relating to the outer shape of the correction plane obtained by optically scanning the correction plane from a direction oblique to the normal direction of the correction plane, and positional information of the correction plane; a first acquisition unit that acquires
a generation unit that generates a measurement error distribution indicating a plurality of measurement errors related to a plurality of measurement distances based on the first scan data and the position information of the correction plane ;
an imaging unit that captures a reference figure attached to the correction plane and outputs it as image data;
The image data is displayed in a live view, and the image data displayed in the live view is viewed from a scanner position which is a predetermined oblique direction with respect to the normal direction of the correction plane and which is a reference distance from the correction plane. a display unit that superimposes and displays image data including a guide figure corresponding to the shape of the reference figure;
and
The imaging unit adjusts the correction plane so that the reference graphic of the image data displayed in the live view and the guide graphic of the superimposed image data match according to a user's operation. A shape measuring device in which a diagonal direction with respect to a normal direction and a distance from the correction plane are adjusted . The generation unit sets a scanning range divided by reference points as a reference point area,
The measurement error distribution is the measurement error for each reference point region calculated from the measurement error for each measurement point of the first scan data.
The shape measuring device according to claim 1. With respect to the reference point areas in which the measurement points do not exist in the first scan data, the generating unit determines that the reference point areas in which the measurement points exist in the first scan data are located at equal measurement distances. 3. The shape measuring apparatus according to claim 2, wherein the measurement error distribution is generated by interpolating using the measurement error of the reference point area. 4. The apparatus according to any one of claims 1 to 3, further comprising a reference distance acquisition unit that acquires a distance from an origin of the measurement coordinate system in the normal direction to the correction plane as the position information of the correction plane. A profile measuring device as described. a second acquisition unit that acquires second scan data relating to the outline of the target obtained by optically scanning the target;
and a correction unit that corrects the second scan data by referring to the measurement error distribution according to the measurement distance of each measurement point for each measurement point of the second scan data. 2. The shape measuring device according to 1. a model generator that generates a three-dimensional object model of the object from the corrected second scan data;
The shape measuring device according to claim 5 , further comprising: an interference determination unit that uses the target model to determine interference between the target and the device in radiotherapy or medical imaging diagnosis. A shape measuring device according to any one of claims 1 to 6 ;
a bed having a top plate movably supported within the scanning range of the shape measuring device;
The correction plane is the top plate,
The first scan data includes a plurality of scan data related to a plurality of tabletop positions,
Radiation therapy system. first scan data relating to the outer shape of the correction plane obtained by optically scanning the correction plane from a direction oblique to the normal direction of the correction plane, and positional information of the correction plane; to obtain;
generating a measurement error distribution indicating a plurality of measurement errors related to a plurality of measurement distances based on the first scan data and the position information of the correction plane ;
an imaging unit imaging a reference figure attached to the correction plane and outputting it as image data;
The image data is displayed in a live view, and the image data displayed in the live view is viewed from a scanner position which is a predetermined oblique direction with respect to the normal direction of the correction plane and which is a reference distance from the correction plane. superimposed display of image data including a guide figure corresponding to the shape of the reference figure;
In order that the reference figure of the image data displayed in the live view and the guide figure of the image data displayed in the superimposed manner match, the imaging unit is rotated in an oblique direction with respect to the normal direction of the correction plane. adjusting the distance from the correction plane;
Shape measurement method including.

Images