JP2009219854A - Device for transferring subject to be tested and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the positioning accuracy of a top board on which a subject to be tested is placed and to simplify the construction of a device for transferring the subject to be tested which transfers the subject to be tested to a shooting space. <P>SOLUTION: The device for transferring an subject to be tested is provided with a scale part 124 which is arranged along the moving direction of the top board 101. A scale detection part 103 which moves with the movement of the top board 101 detects the scale of the scale part 124 by a detection head 131. Signals representing detection information of the detection head 131 is wirelessly transmitted by a transmission part 132. A top board location identifying part 104 wirelessly receives the signals by its reception part 141 and identifies the location of the top board 101 by the obtained detection information. The transmission part 132 is supplied with electric power from a battery part 133 of the scale detection part 103. The battery part 133 is charged by a charging part 125 when the top board 101 is located at a home position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a subject moving apparatus that transports a subject to an imaging space and an imaging apparatus that photographs a subject using the subject moving apparatus.

  An imaging apparatus such as an X-ray CT (Computed Tomography) apparatus generally includes an object moving apparatus for transporting an object to an imaging space. In addition, the subject moving apparatus includes a top plate on which the subject is placed and a top plate support unit that supports the top plate so that the top plate can be transported in a predetermined direction. It is specified and the position is controlled when photographing.

Various proposals have been made to identify the position of the top plate in the subject moving apparatus, but there is a technique that uses a scale as one technique with relatively good position identification accuracy. . For example, in Patent Document 1, a scale unit provided in the top plate support unit along the transport direction of the top plate, a detection head (head) provided on the top plate for detecting the scale of the scale unit, and a detection head There has been proposed a subject moving apparatus having a top plate position specifying unit for specifying the position where the top plate is transported based on the detected information.
JP 2006-061464 A

In a subject moving apparatus using a scale, in general, a metal is often used in a processing apparatus that processes the scale and its detection information, but it is not desirable to transport metal that affects imaging to the imaging space as much as possible. There is a circumstance. Therefore, in a subject moving apparatus using a scale, as shown in Patent Document 1 and FIG. 6, a sensor unit that is a detection head of the scale is usually provided on the top plate side, and the scale unit and its processing device are used. A certain sensor information processing unit is provided on the top plate support unit side. In addition, a cable for transmitting detection information of the sensor unit to the sensor information processing unit is connected between the sensor unit and the sensor information processing unit. And at least part of this cable is cable guide (cable
Guide) and is moved under the top plate in the concave cable duct provided in the top plate support section along the top plate transport direction. To do.

  As described above, in the subject moving apparatus that moves the subject to the imaging space, if it is attempted to detect the position of the top plate on which the subject is placed with high accuracy, the structure becomes complicated, which is disadvantageous in terms of reliability and cost. It is.

  In view of the above circumstances, the present invention captures a subject by using the subject moving apparatus capable of improving the accuracy of the position of the top board and simplifying the structure, and the subject moving apparatus. An object is to provide a photographing apparatus.

In a first aspect, the present invention relates to a subject moving apparatus for moving a subject in an imaging space, and a top plate on which the subject is placed and movable in a predetermined direction from a home position. ,
A scale unit arranged along the predetermined direction, a detection head that detects the scale of the scale unit, a transmission unit that wirelessly transmits a signal representing detection information of the detection head, and accumulated power A power storage unit that supplies the transmission unit, a scale detection unit that moves in the predetermined direction as the top plate moves, and a reception unit that wirelessly receives the signal and obtains the detection information, A top plate position specifying unit that specifies the position of the top plate in the moving direction based on the detection information obtained by the receiving unit, and charging the power storage unit when the top plate is stopped at the home position Provided is a subject movement apparatus including a power feeding unit.

  Here, the home position means a fixed position that is normally arranged when the subject is not imaged, and means, for example, a position where the amount of extension of the top plate is zero.

  In a second aspect, the present invention is such that the top plate is moved by a carriage provided on the top plate and a top plate support portion having a guide for guiding the carriage along the predetermined direction. The object moving apparatus according to the first aspect, wherein the scale detection unit is provided on the carriage, and the scale unit is provided on the top plate support unit in parallel with the guide. I will provide a.

  In a third aspect, the present invention provides the subject movement apparatus according to the first aspect or the second aspect, wherein the power feeding unit charges the power storage unit by electromagnetic induction.

  In a fourth aspect, the present invention provides the subject movement apparatus according to any one of the first to third aspects, wherein the power storage unit includes a secondary battery or a capacitor.

  In a fifth aspect, the present invention provides the method according to any one of the first to fourth aspects, wherein the transmitting unit and the receiving unit transmit and receive the signal using infrared rays, visible light, or radio waves. An object moving apparatus is provided.

  In a sixth aspect, the present invention provides the subject movement apparatus according to the fifth aspect, wherein the receiving unit includes a plurality of receiving elements that are arranged in the predetermined direction and receive the signal.

  In a seventh aspect, the present invention provides the subject moving apparatus according to the fifth aspect or the sixth aspect, wherein the transmitting unit includes a plurality of transmitting elements that are arranged in the predetermined direction and transmit the signal. I will provide a.

  In an eighth aspect, the present invention provides the subject movement according to any one of the first to seventh aspects, wherein the scale unit is a magnetic scale, and the detection head includes a magnetic sensor. Providing equipment.

  In a ninth aspect, the present invention captures image information by imaging the subject moving apparatus according to any one of the first to eighth aspects and the subject placed on the top board. An imaging apparatus including an imaging unit for generating is provided.

  In a tenth aspect, the present invention relates to the present invention, wherein the imaging means rotates and projects an X-ray imaging system including an X-ray tube and an X-ray detector facing each other with the subject interposed therebetween. An imaging apparatus according to the ninth aspect comprising gantry means for acquiring data is provided.

  In an eleventh aspect, the present invention provides the imaging apparatus according to the ninth aspect, wherein the imaging unit includes a gantry unit that detects a spatial nuclear magnetization distribution of the subject by nuclear magnetic resonance.

  According to the present invention, the scale detection unit including the scale unit arranged along the moving direction of the top plate, the scale detection unit moving with the movement of the top plate detects the scale of the scale unit by the detection head, and the detection head by the transmission unit Since the signal representing the detection information is wirelessly transmitted and the top panel position specifying unit wirelessly receives the signal by the receiving unit and identifies the position of the top panel from the obtained detection information, the position specifying accuracy While adopting a position identification method using a good scale, it is possible to eliminate the cable that connects the detection head and the top plate position specifying unit and the members to be provided around it, and the accuracy of specifying the position of the top plate is good In addition, it is possible to realize a subject moving apparatus capable of simplifying the structure.

  Embodiments according to the present invention will be described below.

(First embodiment)
FIG. 1 is a block diagram showing an overall configuration of an X-ray CT apparatus 1 according to an embodiment of the present invention, and FIG. 2 is a configuration diagram showing a main part of the X-ray CT apparatus 1.

  As shown in FIG. 1, the X-ray CT apparatus 1 includes a scanning gantry 2, an operation console 3, and a subject moving unit 4. Each part will be described sequentially.

  The scanning gantry 2 includes an X-ray tube 20, an X-ray tube moving unit 21, a collimator 22, an X-ray detector 23, a data collection unit 24, an X-ray controller 25, and a collimator controller. (Collimator controller) 26, rotating unit 27, and gantry controller 28.

  The scanning gantry 2 scans the subject moved to the imaging space 29 by the subject moving unit 4 and obtains raw data. Here, in the scanning gantry 2, the X-ray tube 20 and the X-ray detector 23 are opposed to each other with an imaging space 29 into which the subject is carried in.

  The X-ray tube 20 is, for example, a rotary anode type and irradiates X-rays. As shown in FIG. 2, the X-ray tube 20 irradiates X-rays having a predetermined intensity to the imaging region of the subject via the collimator 22 based on a control signal CTL 251 from the X-ray controller 25. Further, the X-ray tube 20 is rotated around the column direction z, which is the body axis direction of the subject, by the rotating unit 27 in order to irradiate X-rays from the view direction around the subject.

  As shown in FIG. 2, the X-ray tube moving unit 21 determines the radiation center of the X-ray tube 20 based on the control signal CTL 252 from the X-ray controller 25 and the body of the subject in the imaging space 29 in the scanning gantry 2. It is moved in the column direction z which is the axial direction.

  As shown in FIG. 2, the collimator 22 is disposed between the X-ray tube 20 and the X-ray detector 23. The collimator 22 is composed of, for example, two plates each provided in the channel direction x and the column direction z. Based on the control signal CTL 261 from the collimator controller 26, the collimator 22 moves the two plates provided in each direction independently, and blocks the X-rays emitted from the X-ray tube 20 in each direction. It is formed into a cone shape, and the X-ray irradiation range is adjusted.

  The X-ray detector 23 detects X-rays irradiated from the X-ray tube 20 and transmitted through the subject via the cradle unit 101 of the subject moving unit 4, and the projection data of the subject is converted into an image. Acquired as raw data for forming. Here, the X-ray detector 23 rotates the periphery of the subject around the column direction z by the rotating unit 27 together with the X-ray tube 20, and the subject is detected for each of a plurality of view directions around the subject. Projection data is generated by detecting transmitted X-rays. In the X-ray detector 23, the rotation unit 27 rotates the X-ray tube 20 by the rotation unit 27 and the channel direction x along the direction in which the X-ray tube 20 is rotated around the body axis direction of the subject. The detection elements 23a are two-dimensionally arranged in an array in the column direction z, which is a direction substantially perpendicular to the surface formed by the trajectory. As shown in FIG. 2, the X-ray detector 23 includes a plurality of X-ray detection modules (modules) 23A arranged along the channel direction x and the column direction z. The X-ray detectors 23 are arranged such that, for example, J X-ray detection modules 23A are arranged in J in the channel direction x and I in the column direction z.

  The detection element 23a is, for example, a solid state detector, a scintillator (not shown) that converts X-rays that have passed through the subject into light, and a photodiode (photodiode) that converts light converted by the scintillator into electric charge. (Not shown). The photodiode in the detection element 23a is formed on the same substrate corresponding to the X-ray detection module 23A. The detection element 23a is not limited to this. For example, the detection element 23a is a semiconductor detection element using cadmium tellurium (CdTe) or the like, or an ionization chamber type detection element 23a using xenon gas (Xe gas). It's okay.

  The data collection unit 24 is provided for collecting data by X-rays detected by the X-ray detector 23. The data collection unit 24 collects X-ray projection data of the subject detected by each detection element 23 a of the X-ray detector 23 and outputs the collected data to the operation console 3. As shown in FIG. 2, the data collection unit 24 includes a selection / addition switching circuit (MUX, ADD) 241 and an analog-digital converter (ADC) 242. The selection / addition switching circuit 241 selects projection data from the detection element 23a of the X-ray detector 23 in accordance with the control signal CTL303 from the central processing unit 30, or adds a combination thereof, and the result is analog- Output to the digital converter 242. The analog-to-digital converter 242 converts the projection data selected by the selection / addition switching circuit 241 or added in an arbitrary combination from an analog signal to a digital signal and outputs it to the central processing unit 30.

  As shown in FIG. 2, the X-ray controller 25 outputs a control signal CTL 251 to the X-ray tube 20 in accordance with a control signal CTL 301 from the central processing unit 30 to control X-ray irradiation. The X-ray controller 25 controls, for example, the tube current and irradiation time of the X-ray tube 20. Further, the X-ray controller 25 outputs a control signal CTL 252 to the X-ray tube moving unit 221 in response to the control signal CTL 301 from the central processing unit 30 so as to move the radiation center of the X-ray tube 20 in the column direction z. To control.

  As shown in FIG. 2, the collimator controller 26 outputs a control signal CTL 261 to the collimator 22 in response to the control signal CTL 302 from the central processing unit 30 to shape the X-rays emitted from the X-ray tube 20. 22 is controlled.

  As shown in FIGS. 1 and 2, the rotating unit 27 rotates around the column direction z, which is the body axis direction of the subject, in response to a control signal CTL 28 from the gantry controller 28. An X-ray tube 20, an X-ray tube moving unit 21, a collimator 22, an X-ray detector 23, a data collection unit 24, an X-ray controller 25, and a collimator controller 26 are mounted on the rotating unit 27. The rotating unit 27 changes the position of the subject moved to the imaging space 29 by rotating each unit. As the rotating unit 27 rotates, X-rays are emitted from a plurality of view directions around the subject, and the X-ray detector 23 can detect X-rays transmitted through the subject for each view direction. become. The rotating unit 27 tilts in response to a control signal CTL 28 from the gantry controller 28. The rotation unit 27 tilts around the isocenter of the imaging space 29 so that the subject moves along the horizontal direction in which the subject moves horizontally between the outside and the inside of the imaging space 29 by the object moving unit 4.

  As shown in FIGS. 1 and 2, the gantry controller 28 outputs a control signal CTL 28 to the rotating unit 27 based on a control signal CTL 304 from the central processing unit 30 of the operation console 3, and rotates and tilts the rotating unit 27. To move. That is, the gantry controller 28 rotates the rotating unit 27 to irradiate X-rays from a plurality of view directions around the column direction z of the subject and detect X-rays transmitted through the subject. Further, the gantry controller 28 moves the rotating unit 27 while inclining the rotating unit 27 so that the subject moving unit 4 follows the horizontal direction in which the subject moves horizontally between the outside and the inside of the imaging space 29.

  As illustrated in FIG. 1, the operation console 3 includes a central processing unit 30, an input device 31, a display device 32, and a storage device 33.

  The central processing unit 30 is configured by, for example, a computer, and includes a control unit 41 and an image generation unit 51 as shown in FIG.

  The control unit 41 irradiates the subject with X-rays from the X-ray tube 20 based on the scanning conditions for scanning the subject, and detects the X-rays that pass through the subject with the X-ray detector 23. Each part is controlled to perform scanning. Specifically, the control unit 41 outputs a control signal CTL 30a to each unit based on the scan condition, and causes the scan to be executed. For example, the control unit 41 outputs a control signal CTL 30 b to the subject moving unit 4, and causes the subject moving unit 4 to move the subject between the inside and the outside of the imaging space 29. Further, the control unit 41 outputs a control signal CTL 304 to the gantry controller 28 to rotate the rotation unit 27 of the scanning gantry 2. Further, the control unit 41 outputs a control signal CTL 301 to the X-ray controller 25 so that X-rays are emitted from the X-ray tube 20. And the control part 41 outputs the control signal CTL302 to the collimator controller 26, controls the collimator 22, and shape | molds X-ray | X_line. In addition, the control unit 42 outputs a control signal CTL 303 to the data collection unit 24 and controls to collect projection data obtained by the detection element 23 a of the X-ray detector 23.

  The image generation unit 51 reconstructs an image of the tomographic plane of the subject based on the raw data acquired by the scanning gantry 2. For example, the image generation unit 51 performs preprocessing such as sensitivity correction and beam hardening correction on projection data from a plurality of view directions by a helical scan, and then performs a filter. Reconstruction is performed by processing back projection, and an image of the tomographic plane of the subject is reconstructed and generated.

  The input device 31 of the operation console 3 is configured by an input device (device) such as a keyboard or a mouse, for example. The input device 31 inputs various information such as scan conditions and subject information to the central processing unit 30 based on an input operation of an operator.

  The display device 32 displays an image of the tomographic plane of the subject reconstructed by the image generation unit 51 based on a command from the central processing device 30.

  The storage device 33 is configured by a memory, and stores various data representing a tomographic image of a subject to be reconstructed by the image generation unit 51, a program, and the like. In the storage device 33, the stored data is accessed to the central processing unit 30 as necessary.

  The subject moving unit 4 is provided for moving the subject between the inside and outside of the imaging space 29.

  3, 4, and 5 are diagrams showing the subject moving unit 4. Here, FIG. 3 is a side view of the subject moving unit 4 viewed from the side. FIG. 4 is a perspective view of the subject moving unit 4 as viewed obliquely from the front side, and shows the main part of the subject moving unit 4. FIG. 5 is a rear view of the subject moving unit 4 as viewed from the rear side, and shows the periphery of the carriage unit 121 in FIG.

  As shown in FIG. 3, the subject moving unit 4 includes a cradle unit (top plate) 101, a cradle support unit (top plate support unit) 102, a scale detection unit (scale detection unit) 103, and a cradle. A position specifying unit (top plate position specifying unit) 104.

  The cradle unit 101 includes a placement surface on which the subject is placed, and supports the subject on the placement surface. As shown in FIG. 3, the cradle part 101 is supported by a cradle support part 102, and is arranged in a horizontal direction H substantially horizontal to the placement surface and a vertical direction V substantially perpendicular to the placement surface. It moves and moves between the inside and outside of the imaging space 29 in the scanning gantry 2. As shown in FIG. 3, the cradle unit 101 is fixed to the carriage unit 121 of the cradle support unit 102, slides in the horizontal direction H together with the carriage unit 121, and moves into the imaging space 29 of the scanning gantry 2. . In the cradle unit 101, the X-ray detector 23 is disposed on the surface side opposite to the placement surface on which the subject is placed.

  As shown in FIG. 3, the cradle support unit 102 supports the cradle unit 101 so that the cradle unit 101 slides and moves into the imaging space 29. The cradle support unit 102 includes a carriage unit 121, a guide rail unit 122, a guide rail support unit 123, a scale unit 124, a charging unit (power feeding unit) 125, a horizontal driving unit 126, and a vertical driving unit 127. Have.

  The carriage unit 121 is a carriage that supports the cradle unit 101 and slides in the imaging space 29, and is supported by the guide rail unit 122 as shown in FIGS. The carriage unit 121 is fixed to the end of the cradle unit 101 at a position far from the imaging space 29 so as not to overlap the X-ray irradiation path between the X-ray tube 20 and the X-ray detector 23. As shown in FIGS. 3 and 4, the carriage unit 121 slides the cradle unit 101 into the imaging space 29 by sliding in the direction in which the guide rail unit 122 extends.

  As shown in FIGS. 4 and 5, the guide rail portion 122 is provided on the guide rail support portion 123 and is formed to extend in a direction in which the cradle portion 101 slides. The guide rail part 122 supports the carriage part 121 and allows the cradle part 101 fixed to the carriage part 121 to slide.

  The guide rail support portion 123 is provided to support the guide rail portion 122. For example, as illustrated in FIGS. 4 and 5, the guide rail support portion 123 includes a pair of structures, and the guide rail portions 122 are arranged and supported on the surfaces where the pair of structures face each other. The carriage portion 121 supported by the guide rail portion 122 is sandwiched between the pair of structures facing each other. Although details will be described later, a scale portion 124 is disposed on the guide rail support portion 123.

  The scale part 124 is provided with a scale for detecting the position of the cradle part 101 and extending corresponding to the slide range of the cradle part 101. Here, as shown in FIGS. 3 and 4, the scale portion 124 is arranged to extend to the guide rail support portion 123 of the cradle support portion 102 so as to extend along the direction in which the guide rail portion 122 extends. ing. That is, the scale unit 124 is disposed so as not to overlap the X-ray irradiation path between the X-ray tube 20 and the X-ray detector 23. Moreover, the scale part 124 has a scale formed of a magnetic scale. For example, the scale unit 124 uses a magnetic scale in which N poles and S poles are arranged at a constant pitch along the direction in which the cradle unit 101 moves.

  As shown in FIGS. 3 and 5, the charging unit 125 is provided on the upper surface of the connecting member 128 that connects the two guide rail support portions 123 to each other in the X direction at the bottom surface, that is, on the surface on the cradle unit 101 side. It is electrically connected to a commercial power source and charges a battery unit 133 described later.

  The horizontal drive unit 126 is provided to slide the cradle unit 101 in the horizontal direction H and move it. The horizontal driving unit 126 includes, for example, a roller type driving mechanism, transmits the driving force of a roller driven by an actuator to the cradle unit 101, and moves the cradle unit 101 in the horizontal direction H.

  The vertical drive unit 127 supports the cradle support unit 102 and moves the cradle unit 101 supported by the cradle support unit 102 in the vertical direction V. The vertical drive unit 127 includes, for example, a parallel link type drive mechanism. The vertical drive unit 127 moves the cradle unit 101 in the vertical direction V, for example, by driving a parallel link (not shown) with an actuator (not shown).

  As shown in FIG. 3, the scale detection unit 103 is provided in the carriage unit 121, and includes a sensor unit (detection head) 131, a transmission unit 132, and a battery unit (power storage unit) 133.

  As shown in FIGS. 4 and 5, the sensor unit 131 is arranged on the carriage unit 121 with a certain distance from the scale unit 124 so as to be in a non-contact state with the scale unit 124. That is, the sensor unit 131 is disposed so as not to overlap the X-ray irradiation path between the X-ray tube 20 and the X-ray detector 23. As shown in FIGS. 3 and 4, the sensor unit 131 moves relative to the scale unit 124 in the direction in which the scale unit 124 extends as the cradle unit 101 slides. The scale of the scale unit 124 is detected. Here, the sensor unit 131 includes a magnetic sensor that detects the magnetic scale of the scale unit 124.

  As shown in FIGS. 3 and 4, the transmission unit 132 is provided in the carriage unit 121 and is connected to the sensor unit 131 and the battery unit 133 via a short cable, respectively, and is a signal representing detection information of the sensor unit 131. Is transmitted wirelessly. The cable is configured to include a wiring made of a conductive material, for example. As detection information of the sensor unit 131, for example, an analog signal output from the magnetic sensor, a digital signal converted based on the analog signal, or the like can be considered, but is not particularly limited.

  The battery unit 133 is provided on the bottom surface of the carriage unit 121, that is, the surface on the cradle support unit 102 side, is connected to the transmission unit 132 with a cable, and supplies the accumulated power to the transmission unit 132. As the battery unit 133, for example, a battery composed of a rechargeable secondary battery using a chemical reaction can be considered, but a battery composed of a large capacity capacitor such as an electric double layer capacitor or a polymer capacitor. It may be.

  The cradle position specifying unit 104 includes a receiving unit 141 and a sensor information processing unit 142.

  As shown in FIG. 3, the reception unit 141 is provided at a location different from the cradle unit 101 such as the vertical drive unit 127, and wirelessly receives the signal transmitted from the transmission unit 132 and detects the sensor unit 131. get information.

  As shown in FIG. 3, the sensor information processing unit 142 is provided in a place different from the cradle unit 101 such as the vertical drive unit 127, as with the reception unit 141. The detection information is processed to identify the position of the cradle unit 101 in the moving direction.

  As shown in FIGS. 3 and 5, the charging unit 125 and the battery unit 133 are arranged to face each other when the carriage 121 of the cradle unit 101 is located at the home position. The battery unit 133 is charged by the charging unit 125 when the carriage unit 121 of the cradle unit 101 is stopped at the home position. The battery unit 133 and the charging unit 125 each have a built-in coil for electromagnetic connection, and the charging unit 125 charges the battery unit 133 in a non-contact manner by electromagnetic induction.

  Moreover, the transmission part 132 and the receiving part 141 transmit / receive a signal using an electromagnetic wave by communication systems, such as Bluetooth and WiFi, for example. Note that the transmission unit 132 and the reception unit 141 may transmit and receive signals using other electromagnetic waves such as visible light and infrared light.

  Further, as the storage capacity of the battery unit 133, it is considered that the battery unit 133 can sufficiently be practically used as long as it can operate the transmission unit 132 continuously for about 1 to 2 hours. This is because the time during which the cradle unit 101 is continuously away from the home position is considered to be several tens of minutes at the longest when the movement state of the cradle unit 101 in actual photographing is viewed.

  Hereafter, the operation | movement at the time of image | photographing a subject by X-ray CT apparatus 1 of said this embodiment is demonstrated.

  In the initial state, the cradle unit 101 is located at the home position, and stops at this position until at least the subject is placed on the cradle unit 101. The battery unit 133 is charged by the charging unit 125 while the cradle unit 101 is stopped at the home position. Here, it is assumed that the battery unit 143 is already fully charged.

  When imaging a subject, the subject is usually placed on the cradle unit 101 in the initial state described above. Here, the subject is placed on the placement surface of the cradle unit 101, and the subject is supported by the cradle unit 101.

  Next, scan conditions are set. When setting the scan conditions, the operator inputs each parameter condition of the scan conditions to the input device 31. For example, scan parameters such as a scan method such as a helical scan method, the number of scans corresponding to the number of captured images, a tube current value and a tube voltage value of the X-ray tube 20, an X-ray irradiation time, a slice position, a slice thickness, etc. Set (scan parameter).

  Next, the subject is scanned. When performing scanning, the control unit 41 outputs control signals CTL30a and CTL30b to the scanning gantry 2 and the subject moving unit 4 based on the scanning conditions set as described above.

  Accordingly, the vertical drive unit 127 of the subject moving unit 4 moves the cradle unit 101 in the vertical direction H so that the cradle unit 101 corresponds to the height of the imaging space 29 of the scanning gantry 2. Further, the horizontal driving unit 126 slides the cradle unit 101 in the horizontal direction and moves to the imaging space 29 of the scanning gantry 2.

  At this time, the position of the cradle unit 101 is controlled based on the position in the moving direction of the cradle unit 101 specified by the cradle position specifying unit 104. Specifically, the position of the cradle unit 101 is specified as follows. As the cradle unit 101 slides, the sensor unit 131 moves relative to the scale unit 124 in the extending direction of the scale unit 131 to detect the scale of the scale unit 124. And the detection information of the sensor part 131 is transmitted by the transmission part 132 wirelessly, and the receiving part 141 receives it. The reception unit 141 transmits the detection information obtained by reception to the sensor information processing unit 142. The sensor information processing unit 142 processes the detection information of the sensor unit 131 and specifies the position of the cradle unit 101 in the moving direction. The position of the cradle unit 101 specified by the sensor information processing unit 142 is sent to the horizontal drive unit 126 or the control unit 41 and used for position control of the cradle unit 101. The transmission unit 132 may transmit a signal only when the cradle unit 101 moves, or may transmit a signal periodically. During this time, the transmission unit 132 is supplied with power from the battery unit 133. When the cradle unit 101 moves away from the home position, the battery unit 133 cannot temporarily receive charging from the charging unit 125. However, since the time during which the cradle unit 101 is stopped at the home position before the start of shooting is relatively long, the battery unit 133 is sufficiently charged during this period, and power is supplied to the transmission unit 132 during the shooting period. You can continue.

  At this time, the X-ray controller 25 outputs a control signal CTL 252 to the X-ray tube 20 to irradiate X-rays from the X-ray tube 20. Then, the collimator controller 26 outputs a control signal CTL 302 to the collimator 22 to shape the X-rays from the X-ray tube 20. As a result, the gantry controller 28 outputs a control signal CTL 28 to the scanning gantry 2 to rotate the rotating unit 27 of the scanning gantry 2. In addition, the control unit 41 outputs a control signal CTL 303 to the data collection unit 24, and controls so that projection data obtained by the detection element 23a of the X-ray detector 23 is collected as raw data. Specifically, when performing a helical scan, the cradle part 101 on which the subject is placed is slid in the imaging space 29 along the extending direction of the guide rail 122 while the X-ray is applied to the subject. The tube 20 emits X-rays from a plurality of view directions, and the X-ray detector 23 detects X-rays transmitted through the subject for each view direction via the cradle unit 101 to acquire raw data.

  After that, based on the raw data from each view direction, the image generating unit 51 generates an image of the tomographic plane of the subject at a desired slice position and slice thickness. Here, after the image generation unit 51 performs pre-processing such as sensitivity correction and beam hardening correction on projection data from a plurality of view directions, reconstruction is performed by the filtered back projection method, and the tomography of the subject is performed. Reconstruct and generate an image of the surface.

  After the scan is performed, the cradle unit 101 returns to the home position, and the battery unit 133 is charged again by the charging unit 125.

  As described above, according to the present embodiment, the scale unit 124 that is provided along the moving direction of the cradle unit 101 is provided, and the scale detecting unit 103 that moves as the cradle unit 101 moves moves the scale unit 124 by the sensor unit 131. , And the transmission unit 132 wirelessly transmits a signal representing the detection information of the sensor unit 131, and the cradle position specifying unit 104 wirelessly receives the signal by the reception unit 141, thereby obtaining the detection information obtained. Since the position of the cradle part 101 is specified from the cable, a cable for connecting the sensor part 132 and the cradle position specifying part 104 and a member to be provided around the same while adopting a position specifying method using a scale with high position specifying accuracy. The accuracy of specifying the position of the cradle part 101 is good, and the structure is simplified. Reduction can be achieved a subject moving unit 4, and the X-ray CT apparatus 1 can be realized using the same. Thereby, regarding the subject moving apparatus and the imaging apparatus using the same, the disadvantages in reliability and cost can be solved.

  In addition, according to the present embodiment, since the detection information of the sensor unit 131 is wirelessly sent to the cradle position specifying unit 104, there is no cable that is deformed along with the transport of the cradle unit 101, and a failure due to the disconnection of the cable is not caused. Can be eliminated.

  Moreover, according to this embodiment, since the charging part 125 charges the battery part 133 by electromagnetic induction, it is not necessary to provide the battery terminal 133 and the charging part 125 with a contact terminal for charging. Therefore, the battery unit 133 and the charging unit 125 can be easily waterproofed, and can be protected from body fluid or liquid leaked from the cradle unit 101 without using a special structure.

(Second Embodiment)
Hereinafter, some modified examples of the subject moving unit 4 will be described. In these modified examples, the components other than the transmission unit 132 and the reception unit 141, such as the cradle unit 101, the cradle support unit 102, the scale unit 124, and the vertical drive unit 127, are the same as those in the first embodiment. The description is omitted here.

  6 and 7 are views showing a subject moving unit 4A that is a first modification of the subject moving unit 4. FIG.

  In the subject moving unit 4A, other components excluding the transmitting unit 132 and the receiving unit, such as a scale, are the same as those in the first embodiment. The transmission unit 132 includes a single light emitting element 132p and a single light emitting element driving unit 132d.

  The light emitting element driving unit 132d is disposed on the carriage unit 121, and is connected to the light emitting element 132p, the battery unit 133, and the sensor unit 131 through a cable. The light emitting element driving unit 132d receives supply of electric power from the battery unit 133, and sends a driving signal to the light emitting element 132p based on detection information of the sensor unit 131.

  The light emitting element 132p is disposed on the lower surface of the carriage unit 121, and is connected to the light emitting element driving unit 132d by a cable. The light emitting element 132p emits an infrared ray B1 carrying detection information of the sensor unit 131 based on the drive signal sent from the light emitting element driving unit 132d. The intensity | strength of infrared rays B1 is weak, for example, the distance which can be communicated is about 30 cm. The infrared ray B1 has a certain degree of directivity. Here, the position of the light emitting element 132p is tilted so that the emission central axis of the infrared ray B1 is tilted by a predetermined angle in the −y direction with respect to the + z direction. As a result, the light receiving elements described later can be efficiently included in the radiation region of the infrared ray B1, and the number of necessary light receiving elements can be reduced.

  On the other hand, the receiving unit 141 includes a plurality of light receiving elements 141p and a single A / D converter 141d.

  The plurality of light receiving elements 141p are arranged at predetermined intervals in the z direction in the cradle support portion 102, and are connected to the A / D converter 141d in parallel by cables. Further, as shown in FIG. 7, no matter which position the cradle unit 101 moves, any one of the light receiving elements 141p always enters the radiation region of the infrared ray B1 emitted from the light emitting element 132p. An arrangement interval is set. The arrangement interval of the light receiving elements 141p is, for example, about 10 to 20 cm. Each light receiving element 141p receives the infrared ray B1 when the light receiving element 141p enters the radiation region of the infrared ray B1, and outputs an analog electric signal corresponding to the infrared ray B1. Since the individual light receiving elements 141p are connected in parallel, at least the maximum level signal among the output analog electric signals is input to the A / D converter 141d.

  The A / D converter 141d is disposed in the vertical drive unit 127, and is connected to the plurality of light receiving elements 141p and the sensor information processing unit 142 by cables. The A / D converter 141d converts the analog electrical signal sent from the light receiving element 141p into a digital signal representing the detection information of the sensor unit 131 and outputs the digital signal to the sensor information processing unit 142.

  According to such an embodiment, since the plurality of light receiving elements 141p provided at intervals in the moving direction of the cradle unit 101 are provided, wireless communication for transmitting detection information of the sensor unit 31 is infrared communication. Therefore, it is possible to eliminate adverse effects on other devices due to radiation noise of electromagnetic waves, reduce the size of the battery unit 133 due to a reduction in power consumption of the transmission unit 131, and the like.

(Third embodiment)
FIGS. 8 and 9 are views showing a subject moving unit 4B which is a second modification of the subject moving unit 4. FIG. 8 and 9, the upper part shows a top view and the lower part shows a side view.

  In the subject moving unit 4B, the transmitting unit 132 includes a single light emitting element 132p and a single light emitting element driving unit 132d, both of which are carriage units, as in the case of the subject moving unit 4A. 121. However, the light emitting element 132p is an element that outputs infrared laser light having higher directivity, such as a semiconductor laser.

  The light emitting element 132p emits infrared laser light B2 carrying detection information of the sensor unit 131 based on the drive signal sent from the light emitting element driving unit 132d. Although the intensity of the infrared laser beam B2 is weak, the communicable distance is relatively long, for example, about 60 cm, because the directivity is strong. Here, the position of the light emitting element 132p is tilted so that the emission central axis of the infrared laser beam B2 is tilted by a predetermined angle in the + x direction with respect to the + z direction. Thereby, the light emitting element 132p and the light receiving system of the infrared laser beam B2 are not located on the same line in the z direction, and when the cradle part 101 moves in the z direction, the light emitting element 132p and the light receiving system are spatially separated. You can avoid interfering with.

  On the other hand, the receiving unit 141 includes a plurality of reflecting plates 141m, the same number of light receiving elements 141p, and a single A / D converter 141d.

  The reflectors 141m and the light receiving elements 141p are combined on a one-to-one basis, and these combinations are arranged at a predetermined interval in the z direction in the cradle support portion 102. As shown in FIG. 9, regardless of the position of the cradle unit 101, the infrared laser beam B2 emitted from the light emitting element 132p is always incident on one of the reflecting plates 141m, and the reflected light is received by the light receiving element. The arrangement interval, posture, reflection surface shape of the reflecting plate 141m, the positional relationship between the pair of reflecting plate 141m and the light receiving element 141p, and the like are set so that the light is received by 141p. In addition, the arrangement | positioning space | interval of the reflecting plate 141m is about 30-40 cm, for example.

  According to such an embodiment, since infrared laser light having strong directivity is used, infrared light can be further transmitted with less energy, and it is possible to cope with fewer light receiving elements.

(Fourth embodiment)
FIG. 10 is a diagram illustrating a subject moving unit 4 </ b> C that is a third modification of the subject moving unit 4. In the subject moving unit 4C, the transmission unit 132 includes a plurality of light emitting elements 132p and a single light emitting element driving unit 132d.

  The light emitting element driving unit 132d is disposed on the carriage unit 121, and is connected to the battery unit 133, the sensor unit 131, and the plurality of light emitting elements 132p by cables. The light emitting element driving unit 132d receives power supply from the battery unit 133, and sends a driving signal to the plurality of light emitting elements 132p based on the detection information of the sensor unit 131.

  The plurality of light emitting elements 132p are arranged on the lower surface of the cradle part 101 at a predetermined interval in the z direction, and are connected in parallel with the light emitting element driving part 132d by a cable. Each light emitting element 132p emits an infrared ray B3 carrying detection information of the sensor unit 131 based on a driving signal sent from the light emitting element driving unit 132d. The intensity | strength of infrared rays B3 is weak, for example, the distance which can communicate is about 30 cm. The infrared ray B3 has a certain degree of directivity. Here, the position of the light emitting element 132p is tilted so that the emission central axis of the infrared ray B1 is tilted by a predetermined angle in the −y direction with respect to the + z direction.

  On the other hand, the receiving unit 141 includes a plurality of light receiving elements 141p and a single A / D converter 141d.

  The plurality of light receiving elements 141p are arranged at predetermined intervals in the z direction in the cradle support portion 102, and are connected to the A / D converter 141d in parallel by cables. In addition, regardless of the position of the cradle unit 101, the arrangement interval of the light receiving elements 141p is set so that the infrared light B3 emitted from the light emitting elements 132p is always received by the light receiving elements 141p in a plurality of different regions. . The arrangement interval of the light receiving elements 141p is, for example, about 10 to 20 cm.

  The A / D converter 141d is disposed in the vertical drive unit 127, and is connected to the plurality of light receiving elements 141p and the sensor information processing unit 142 by cables.

  According to such an embodiment, since a plurality of light emitting elements and light receiving elements are arranged, it is possible to create a state where infrared light reception is always performed at a plurality of locations, and more stable infrared communication can be performed. it can.

(Fifth embodiment)
FIG. 11 is a diagram showing a subject moving unit 4D that is a fourth modification of the subject moving unit 4. As shown in FIG. The subject moving unit 4D is based on the subject moving unit 4C and has the same number of control information as the operation panel 151, the control information light emitting element driving unit 152d, the plurality of control information light emitting elements 152p, and the control information light emitting elements 152p. The configuration further includes a light receiving element 153p and a control information A / D converter 153d.

  The operation panel 151 is provided in the cradle unit 101 and is connected to the control information light emitting element driving unit 152d by a cable. The operation panel 151 receives an operation for controlling the position of the cradle unit 101 by an operator.

  The control information light emitting element driving unit 152d is disposed in the cradle unit 101, and is connected to the battery unit 131, the operation panel 151, and the plurality of control information light emitting elements 152p by cables. The control information light emitting element driving unit 152d receives power supply from the battery unit 133, and sends a drive signal to the plurality of control information light emitting elements 152p based on the control information obtained from the operation panel 151.

  Like the plurality of light emitting elements 132p, the plurality of control information light emitting elements 152p are arranged at predetermined intervals in the z direction on the lower surface of the cradle unit 101, and are arranged in parallel with the control information light emitting element drive unit 152d. It is connected. The light emitting element 132p emits infrared B3 having a first frequency, whereas the control information light emitting element 152p emits infrared B4 having a second frequency different from the first frequency.

  Similar to the plurality of light receiving elements 141p, the plurality of control information light receiving elements 153p are arranged at predetermined intervals in the z direction in the cradle support portion 102, and are connected in parallel with the control information A / D converter 153d by cables. It is connected. The light receiving surfaces of the plurality of light receiving elements 141p are provided with color filters that pass only infrared light in the first frequency band, and the light receiving surfaces of the plurality of light receiving elements for control information 153p are in the second frequency band. It has a color filter that allows only infrared rays to pass through. Thereby, it is possible to prevent interference between communication for transmitting detection information of the sensor unit 131 and communication for transmitting control information by the operation panel 151.

  The control information A / D converter 153d is disposed in the vertical drive unit 127, and is connected to the plurality of control information light receiving elements 153p and the sensor information processing unit 142 by cables.

  According to such an embodiment, since a plurality of types of information can be communicated using different channels, wireless communication superior in real-time characteristics can be achieved as compared with the case where a plurality of types of information are transmitted through one channel. It becomes possible.

  In implementing the present invention, the present invention is not limited to the above-described embodiment, and various modifications can be employed.

  For example, in the above-described embodiment, the slide position of the cradle part is detected using a scale part in which the scale is formed of a magnetic scale and a sensor part formed of a magnetic sensor that detects the magnetic scale. However, it is not limited to this. For example, the slide position of the cradle unit may be detected using a scale unit in which the scale is formed of an optical scale and a sensor unit formed of an optical sensor that detects the optical scale. Further, for example, the scale unit has a scale unit in which a high reflection surface and a low reflection surface are alternately arranged as a scale in a direction in which the cradle unit slides, and a sensor unit including a light emitting element and a light receiving element, and the scale unit is reflected. Light is detected by the sensor unit, and the position where the cradle unit slides is detected.

  Further, for example, in the above-described embodiment, the sensor unit is in a non-contact state with respect to the scale unit, but the present invention is not limited to this, and the sensor unit is disposed so as to be in contact with the scale unit. It may be.

  Further, for example, in the above embodiment, the charging unit charges the battery unit by electromagnetic induction. However, the charging unit may be directly charged by contacting the terminal.

  Further, for example, in the above-described embodiment, power is supplied from the cradle support part side to the cradle part side via the battery part provided in the cradle part, but between the cradle support part and the cradle part. The electric power may be transmitted more directly by electromagnetic induction using a coil.

  In addition, for example, in the second to fifth embodiments, infrared communication using the light emitting element 132p and the light receiving element 141p has been described, and a transmitting element that outputs electromagnetic waves (radio waves) having a frequency lower than that of infrared light It is good also as radio wave communication using the receiving element which receives the electromagnetic waves. In this case, wireless communication for transmitting the detection information of the sensor unit 31 can be realized with a weak radio wave, and adverse effects due to radiation noise can be suppressed and component costs can be reduced. Moreover, you may consider the structure by the combination of a some transmitting element and a single receiving element, or the combination of a some light emitting element and a single light receiving element.

  Further, for example, in the above embodiment, the subject moving unit is applied to a general X-ray CT apparatus, but may be applied to other imaging apparatuses such as a PET-CT apparatus and an MR apparatus. .

1 is a block diagram illustrating an overall configuration of a photographing apparatus according to a first embodiment. It is a block diagram which shows the principal part of the imaging device by 1st Embodiment. It is the side view which looked at the subject moving part in a 1st embodiment from the side. It is a perspective view which shows the principal part of the subject moving part in 1st Embodiment. It is the rear view which looked at the subject moving part in a 1st embodiment from the back side. It is the side view which looked at the subject moving part in a 2nd embodiment from the side. It is the side view which looked at the state which moved the cradle part of the subject moving part in 2nd Embodiment from the side surface side. It is the figure which looked at the subject moving part in 3rd Embodiment from the side surface side and the upper surface side. It is the figure which looked at the state which moved the cradle part of the subject moving part in 3rd Embodiment from the side surface side and the upper surface side. It is the side view which looked at the subject moving part in a 4th embodiment from the side. It is the side view which looked at the subject moving part in a 5th embodiment from the side.

Explanation of symbols

1 X-ray CT system (imaging system)
2 Scanning gantry (gantry means)
3 Operation console 4 Subject moving part (Subject moving device)
20 X-ray tube 21 X-ray tube moving unit 22 Collimator 23 X-ray detector 23A X-ray detection module 24 Data collection unit 241 Selection / addition switching circuit 242 Analog-digital converter 25 X-ray controller 26 Collimator controller 27 Rotating unit 28 Gantry Controller 29 Shooting space 30 Central processing unit 31 Input device 32 Display device 33 Storage device 41 Control unit 51 Image generation unit 101 Cradle unit (top plate)
102 Cradle support (top support)
103 Scale detector (scale detector)
104 Cradle position specifying part (top plate position specifying part)
121 Carriage part (carriage part)
122 Guide rail (guide)
123 Guide rail support part 124 Scale part (scale part)
125 Charging part (power feeding part)
126 Horizontal driving unit 127 Vertical driving unit 128 Connecting member 131 Sensor unit (detection head)
132 Transmitter (transmitter)
132p Light-emitting element 132d Light-emitting element drive part 133 Battery part (electric storage part)
141 Receiver (Receiver)
141p Light-receiving element 141d A / D converter 142 Sensor information processing unit 151 Operation panel 152p Light-emitting element for control information 152d Light-emitting element driving unit for control information 153p Light-receiving element for control information 153d A / D converter for control information

Claims (11)

In the subject moving apparatus that moves the subject in the imaging space,
A top plate on which the subject is placed and is movable in a predetermined direction from the home position;
A scale portion arranged along the predetermined direction;
A detection head that detects a scale of the scale unit, a transmission unit that wirelessly transmits a signal representing detection information of the detection head, and a power storage unit that supplies accumulated power to the transmission unit, A scale detector that moves in the predetermined direction along with the movement;
A receiving unit that wirelessly receives the signal to obtain the detection information; and a top plate position specifying unit that specifies a position of the top plate in a moving direction based on the detection information obtained by the receiving unit;
A subject moving apparatus comprising: a power feeding unit that charges the power storage unit when the top plate is stopped at the home position. The top plate is movable by a carriage provided on the top plate and a top plate support portion having a guide for guiding the carriage along the predetermined direction,
The scale detector is provided on the carriage,
The subject moving apparatus according to claim 1, wherein the scale unit is provided on the top plate support unit in parallel with the guide.   The subject movement apparatus according to claim 1, wherein the power feeding unit charges the power storage unit by electromagnetic induction.   The subject movement apparatus according to any one of claims 1 to 3, wherein the power storage unit includes a secondary battery or a capacitor.   5. The subject movement apparatus according to claim 1, wherein the transmission unit and the reception unit transmit and receive the signal using infrared rays, visible rays, or radio waves.   The subject moving apparatus according to claim 5, wherein the receiving unit includes a plurality of receiving elements that are arranged in the predetermined direction and receive the signal.   The subject moving apparatus according to claim 5, wherein the transmitting unit includes a plurality of transmitting elements that are arranged in the predetermined direction and transmit the signal. The scale portion is a magnetic scale,
The subject movement apparatus according to claim 1, wherein the detection head includes a magnetic sensor. The subject movement apparatus according to any one of claims 1 to 8,
An imaging apparatus comprising: imaging means for imaging an object placed on the top board and generating image information.   The imaging means comprises a gantry means for acquiring projection data by rotating an X-ray imaging system including an X-ray tube and an X-ray detector opposed to each other with the subject interposed therebetween. 9. The photographing apparatus according to 9. The imaging apparatus according to claim 9, wherein the imaging unit includes a gantry unit that detects a spatial nuclear magnetization distribution of the subject by a nuclear magnetic resonance method.

Images