JP2017064062A - Mounting device and X-ray CT apparatus - Google Patents

Abstract

An object of the present invention is to cope with an increase in the number of channels and high-speed rotation of a rotary pedestal by maintaining DC balance without requiring a stabilization period for adjusting the DC balance in a pedestal device. [Solution] A gantry device 21 includes an X-ray tube 51 that emits X-rays, an X-ray detector 53 that includes a plurality of X-ray detection elements, and an output of the X-ray detector 53. A DAS 54 that digitally converts data, a rotating pedestal 32 that holds an X-ray tube 51, an The rotary mount 32 is equipped with a channel switching circuit 84 that synchronizes the output of the converted packet data with the transmission completion timing of the converted packet data. , has. [Selection diagram] Figure 1

Description

  The present embodiment as one aspect of the present invention relates to a gantry device and an X-ray CT (computed tomography) device.

  An X-ray CT apparatus provides information about a subject based on the intensity of X-rays that have passed through the subject, and includes many medical practices such as disease diagnosis / treatment and surgical planning. Plays an important role.

  The X-ray CT apparatus includes a gantry device that holds an X-ray tube, an X-ray detector, and a conversion unit and includes a rotating unit that rotates with respect to a fixed unit. The gantry device includes a non-contact transmission / reception unit that transmits digital data from the rotating unit side to the fixed unit side by a non-contact communication method. In order to reduce the mounting space of the non-contact transmission / reception unit, there is a technique of switching the channel of packet data transmitted to the fixed unit side (channel switching) according to the view angle (rotation angle) of the rotation unit.

JP 2010-11979 A

  However, according to the conventional channel switching technique, the channel switching timing is not synchronized with the packet data transmission completion timing, and there is a possibility that the packet data may be biased at the channel switching timing. Therefore, DC balance adjustment time (time for channel switching) is required. Since it is necessary to provide a DC balance adjustment time, there are restrictions on an increase in the number of channel divisions and a high-speed rotation of the rotating unit.

  Here, the DC balance is to avoid the phenomenon that the voltage level is fixed to the equivalent of “0” when “0” continues in the digital data array and cannot be increased to the voltage level until the equivalent of “1” thereafter. Furthermore, it means that “0” and “1” are arranged without deviation before data transmission.

  In order to solve the above-described problem, a gantry device according to the present embodiment includes an X-ray tube that emits X-rays, an X-ray detector that includes a plurality of X-ray detection elements and detects the X-rays. A conversion unit that digitally converts output data of the X-ray detector, a rotation unit that holds the X-ray tube, the X-ray detector, and the conversion unit and rotates with respect to the fixed unit; and a view angle The rotation unit is provided with a channel switching circuit that synchronizes the channel switching timing according to the transmission completion timing of the packet data converted from the output of the conversion unit, and the packet data is not contacted from the rotation unit to the fixed unit And a non-contact transmission / reception unit that transmits the communication method.

  An X-ray CT apparatus according to the present embodiment includes an X-ray tube that emits X-rays and a plurality of X-ray detection elements in order to solve the above-described problems, and detects the X-rays. , A conversion unit that digitally converts output data of the X-ray detector, a rotation unit that holds the X-ray tube, the X-ray detector, and the conversion unit and rotates with respect to the fixed unit, a view The rotation unit includes a channel switching circuit that synchronizes the timing of channel switching according to a corner with the transmission completion timing of the packet data converted from the output of the conversion unit, and the packet data is transferred from the rotation unit to the fixed unit. A non-contact transmission / reception unit that transmits by a non-contact communication method; and an image processing device that generates an image based on the output transmitted to the fixed unit.

The figure which shows the structural example of the X-ray CT apparatus which concerns on this embodiment. The figure which shows the detail of a one part structure of a non-contact transmission / reception part. (A)-(F) is a figure for demonstrating the change according to the view angle of three outputs allocated to two channels. (A)-(F) is a figure for demonstrating the change according to the view angle of three outputs allocated to two channels. The figure which shows two channels allocated to three outputs for every view angle as a table | surface. The figure which shows the detail of a structure of a non-contact transmission / reception part. The figure which shows the detail of a structure of the 1st modification of the non-contact transmission / reception part shown in FIG. The figure which shows the detail of a structure of the 2nd modification of the non-contact transmission / reception part shown in FIG.

  A gantry device and an X-ray CT apparatus according to the present embodiment will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram illustrating a configuration example of an X-ray CT apparatus according to the present embodiment.

  FIG. 1 shows an X-ray CT apparatus 1 according to the present embodiment. The X-ray CT apparatus 1 is mainly composed of a scanner device 11 and an image processing device (console) 12. The scanner device 11 of the X-ray CT apparatus 1 is usually installed in an examination room and configured to generate X-ray transmission data related to a patient O (subject). On the other hand, the image processing apparatus 12 is usually installed in a control room adjacent to the examination room, and is configured to generate projection data based on transmission data and generate / display a reconstructed image.

  The scanner device 11 includes a gantry device 21, a couch device 22, and a controller 23.

  The gantry device 21 includes a fixed gantry 31 fixed to a base part (not shown), a rotary gantry 32, a slip ring 33, and a non-contact transmitting / receiving unit 34.

  The fixed mount 31 includes a rotation drive device 41. The rotation drive device 41 is a mechanism for rotating the rotating mount 32 relative to the fixed mount 31 so that the rotating mount 32 rotates around the opening including the rotation center in a state where the rotating mount 32 maintains the positional relationship under the control of the controller 23. Have

  The rotating gantry 32 integrally holds an X-ray source (X-ray tube) 51, a diaphragm 52, an X-ray detector 53, a DAS (data acquisition system) 54, and a high voltage generator 55. In the state where the X-ray tube 51 and the X-ray detector 53 are opposed to each other, the rotary mount 32 is configured so that the X-ray tube 51, the diaphragm 52, the X-ray detector 53, the DAS 54, and the high voltage generator 55 are integrated as a patient O. It is configured to be able to rotate around. In addition, a direction parallel to the rotation center axis of the rotating gantry 32 is defined as a z-axis direction, and planes orthogonal to the z-axis direction are defined as an x-axis direction and a y-axis direction.

  The X-ray tube 51 generates an X-ray by causing an electron beam to collide with a metal target in accordance with the tube voltage supplied from the high voltage generator 55 and irradiates the X-ray detector 53 with the electron beam. Fan beam X-rays and cone beam X-rays are formed by X-rays emitted from the X-ray tube 51. The X-ray tube 51 is supplied with electric power necessary for X-ray irradiation under the control of the controller 23 via the high voltage generator 55.

  The diaphragm 52 adjusts the irradiation range (irradiation field) of X-rays irradiated from the X-ray tube 51 by a diaphragm driving device (not shown). That is, the X-ray irradiation range in the slice direction can be changed by adjusting the aperture of the diaphragm 52.

  The X-ray detector 53 is a one-dimensional array type detector having a plurality of detection elements in the channel direction and a single detection element in the column (slice) direction. Alternatively, the X-ray detector 53 is a two-dimensional array detector (also referred to as a multi-slice detector) having a matrix, that is, a plurality of detection elements in the channel direction and a plurality of detection elements in the slice direction. When the X-ray detector 53 is a multi-slice detector, a three-dimensional imaging region having a width in the column direction can be imaged by one scan (volume scan). The X-ray detector 53 detects X-rays emitted from the X-ray tube 51 under the control of the controller 23.

  The DAS 54 collects data. The DAS 54 amplifies the signal of transmission data (X-ray detection data) detected by each detection element of the X-ray detector 53 and converts it into a digital signal. The output data of the DAS 54 is supplied to the image processing apparatus 12 via the non-contact transmission / reception unit 34.

  The high voltage generator 55 supplies the power supplied via the slip ring 33 to the X-ray tube 51 under the control of the controller 23.

  The slip ring 33 of the gantry device 21 is a mechanism for transmitting electric power and signals through an annular electric circuit and a brush arranged concentrically with respect to the rotating gantry 32.

  The non-contact transmission / reception unit 34 of the gantry device 21 includes a transmission circuit 34a on the rotary gantry 32 side and a reception circuit 34b (both shown in FIG. 2) on the fixed gantry 31 side. The non-contact transmission / reception unit 34 transmits output data from the rotating gantry 32 to the fixed gantry 31 by wireless communication as a non-contact communication method. For example, the non-contact transmission / reception unit 34 transmits output data from the rotating gantry 32 to the fixed gantry 31 by an optical method, a capacitive coupling method, or a radio wave method as a non-contact communication method. The detailed configuration and operation of the contactless transmission / reception unit 34 will be described later with reference to FIGS.

  The bed device 22 of the scanner device 11 includes a top plate 22a and a top plate driving device 22b. The patient can be placed on the top plate 22a.

  The top plate driving device 22b has a mechanism for moving the top plate 22a up and down along the y-axis direction and moving in and out along the z-axis direction under the control of the controller 23. The top board drive device 22b inserts the patient O placed on the top board 22a toward the opening including the rotation center of the rotary mount 32, and retracts the patient O placed on the top board 22a from the opening. .

  The controller 23 includes a processing circuit (not shown), a memory, and the like. The controller 23 controls the rotation drive device 41 of the gantry device 21, the X-ray detector 53, the DAS 54, the high voltage generator 55, the top plate drive device 22 b of the bed device 22, and the like according to instructions from the image processing device 12. To execute the scan.

  The image processing apparatus 12 of the X-ray CT apparatus 1 is configured based on a computer, and can communicate with a network (local area network) N. The image processing apparatus 12 generally includes basic hardware such as a processing circuit 61, a storage circuit (storage unit) 62, an input circuit (input unit) 63, a display (display unit) 64, and an IF (communication unit) 65. Consists of The processing circuit 61 is interconnected to each hardware component constituting the image processing device 12 via a bus as a common signal transmission path. Note that the image processing apparatus 12 may include a storage medium drive.

  The processing circuit 61 means a dedicated or general-purpose CPU (central processing unit) or MPU (micro processor unit), an application specific integrated circuit (ASIC), a programmable logic device, and the like. As the programmable logic device, for example, a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA) are used. Can be mentioned. The processing circuit 61 reads out and executes a program stored in the storage circuit 62 or directly incorporated in the processing circuit 61.

  The processing circuit 61 may be configured by a single circuit or a combination of a plurality of independent circuits. In the latter case, the storage circuit 62 for storing the program may be provided for each processing circuit 61, or the single storage circuit 62 stores the program corresponding to the functions of a plurality of circuits (processing circuits). It may be.

  The processing circuit 61 reads various control programs stored in the storage circuit 62 to realize functions, and comprehensively controls processing operations in the units 62 to 65.

  The storage circuit 62 is configured by a semiconductor memory device such as a RAM (Random Access Memory) and a flash memory, a hard disk, an optical disk, and the like. The storage circuit 62 may be configured by a portable medium such as a USB (Universal Serial Bus) memory and a DVD (Digital Video Disk). The storage circuit 62 stores various processing programs used in the processing circuit 61 (including an OS (operating system) in addition to an application program), data necessary for executing the program, and medical images. The OS can also include a GUI (Graphical User Interface) that can use the graphics to display information on the display 64 for the operator and perform basic operations by the input circuit 63.

  The input circuit 63 is a circuit for inputting a signal from an input device such as a pointing device (such as a mouse) or a keyboard that can be operated by an operator. Here, the input device itself is also included in the input circuit 63. . When the input device is operated by the operator, the input circuit 63 generates an input signal corresponding to the operation and outputs it to the processing circuit 61. Note that the image processing apparatus 12 may include a touch panel in which an input device is configured integrally with the display 64.

  The display 64 is configured by a general display output device such as a liquid crystal display or an OLED (organic light emitting diode) display, and displays image data generated under the control of the processing circuit 61.

  The IF (interface) 65 is configured by a connector that conforms to a parallel connection specification or a serial connection specification. When the X-ray CT apparatus 1 is provided on a network, the IF 65 transmits / receives information to / from an external apparatus on the network. For example, the IF 65 communicates with an external device by transmitting image data generated by the X-ray CT apparatus 1 to an image management apparatus or an interpretation terminal (not shown).

  The image processing apparatus 12 performs logarithmic conversion processing or correction processing (pre-processing) such as sensitivity correction on the raw data input from the DAS 54 of the scanner device 11 to generate projection data and store it in the storage circuit 62. . Further, the image processing device 12 performs scattered radiation removal processing on the preprocessed projection data. The image processing device 12 removes scattered radiation based on the value of the projection data within the X-ray exposure range, and based on the projection data to be subjected to scattered radiation correction or the value of the adjacent projection data. The estimated scattered radiation is subtracted from the target projection data to perform scattered radiation correction. The image processing device 12 generates image data based on the corrected projection data and stores it in the storage circuit 62 or displays it on the display 64.

  Next, the details of the configuration of a part of the non-contact transmitting / receiving unit 34 (part related to the prior art) will be described.

  FIG. 2 is a diagram illustrating details of a partial configuration of the non-contact transmission / reception unit 34.

  As shown in FIG. 2, the non-contact transmission / reception unit 34 includes a transmission circuit 71 on the rotating gantry 32 (shown in FIG. 1) and a receiving circuit 72 on the fixed gantry 31 (shown in FIG. 1) side. The transmission circuit 71 has a plurality (n (n = 3, 4,...)) Assigned to a plurality (m (m = 2, 3,...)) Of channels according to the view angle (rotation angle) of the rotary mount 32. ..., N> m)) while switching the output, data is transmitted and received. The n outputs outputted from the m detection element groups into which the entire detection elements constituting the X-ray detector 53 (shown in FIG. 1) are classified are assigned to m channels.

  The transmission circuit 71 includes a packetizing circuit 81, a DC balance adjustment circuit 82, a P / S conversion circuit 83, and a channel switching circuit 84.

  The packetizing circuits 811 and 812 of the packetizing circuit 81 packetize the projection data output from the DAS 54, add the incidental information to the header to generate packet data, respectively, and send them to the DC balance adjustment circuit 82 in parallel. To transmit.

  The DC balance adjustment circuits 821 and 822 of the DC balance adjustment circuit 82 adjust the DC balance of the packet data transmitted from the packetizing circuit 81 and transmit the adjusted packet data to the P / S conversion circuit 83, respectively. For example, the DC balance adjustment circuit 82 executes bit number conversion processing such as 8B10B conversion and 64B66B conversion, Manchester conversion, and the like in order to adjust the DC balance.

  The P / S conversion circuits 831 and 832 of the P / S conversion circuit 83 convert the transmission method of the packet data after the DC balance adjustment transmitted from the DC balance adjustment circuit 82 from the parallel method to the serial method, respectively, and change the channel switching circuit. 84, respectively.

  The channel switching circuit 84 uses the serial-type packet data transmitted from the P / S conversion circuit 83 and the channel switching signal U, and receives the receiving circuit according to the view angle of the rotary mount 32 (shown in FIG. 1). The channel of the packet data transmitted to 72 (fixed part side) is switched and wirelessly transmitted to the receiving circuit 72. Here, the channel switching signal U is a signal based on the view angle (rotary encoder information) of the rotary mount 32 (shown in FIG. 1) generated by the controller 23 or the like. Details of the operation of the channel switching circuit 84 will be described later with reference to FIGS.

  Note that, between the DAS 54 and the packetizing circuit 81, between the packetizing circuit 81 and the DC balance adjustment circuit 82, between the DC balance adjustment circuit 82 and the P / S conversion circuit 83, and a P / S conversion circuit. 83 and the channel switching circuit 84 are connected by a transmission path composed of an optical module such as an optical fiber. Data transmission is performed by optical communication from the DAS 54 through the transmission path to the channel switching circuit 84 through the packetization circuit 81, the DC balance adjustment circuit 82, and the P / S conversion circuit 83 in this order.

  The reception circuit 72 includes an S / P conversion circuit 91.

  The S / P conversion circuits 911 to 913 of the S / P conversion circuit 91 receive packet data wirelessly transmitted from the transmission circuit 71 for every n outputs, respectively, and change the packet data transmission method from the serial method to the parallel method. The data is converted and transmitted to the image processing apparatus 12 via the controller 23 (shown in FIG. 1).

  Note that the S / P conversion circuit 91 and the image processing device 12 are connected by a transmission path made of an optical module such as an optical fiber. Data transmission is performed by optical communication from the S / P conversion circuit 91 to the image processing device 12 via the transmission path.

  Next, details of the operation of the non-contact transmitting / receiving unit 34 will be described.

  3A to FIG. 3F and FIG. 4A to FIG. 4F follow the view angles of the three outputs SA to SC assigned to the two channels CH1 and CH2. It is a figure for demonstrating a change. FIG. 5 is a table showing two channels CH1 and CH2 assigned to the three outputs SA to SC for each view angle.

  As described above, the non-contact transmission / reception unit 34 (shown in FIG. 2) has 3 (n = 3) outputs (SA) assigned to 2 (m = 2) channels according to the view angle of the rotary mount 32. , SB, SC) while performing wireless communication. That is, the transmission circuit 71 (illustrated in FIG. 2) performs wireless communication with the reception circuit 72 while switching the three outputs assigned to the two channels according to the view angle of the rotary mount 32.

  FIG. 3A shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 0 °. As shown in FIG. 3A, the view angle θ of 0 ° is a stage in which the output SA is switched from the second channel CH2 to the first channel CH1, and the output SB is the first of the two channels CH1 and CH2. In this stage, the output SC is assigned to the second channel CH2 out of the two channels CH1 and CH2.

  That is, when the view angle θ is 0 °, the output SB is transmitted to the channel switching circuit 84 via the packetizing circuit 811, the DC balance adjustment circuit 821, and the P / S conversion circuit 831 shown in FIG. The signal is wirelessly transmitted from the circuit 84 to the S / P conversion circuit 912 of the reception circuit 72. When the view angle θ is 0 °, the output SC is transmitted to the channel switching circuit 84 via the packetization circuit 812, the DC balance adjustment circuit 822, and the P / S conversion circuit 832 shown in FIG. The signal is wirelessly transmitted from the circuit 84 to the S / P conversion circuit 912 of the reception circuit 72. Subsequently, when the view angle θ advances from 0 ° to 30 °, the stage shown in FIG.

  FIG. 3B shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 30 °. As shown in FIG. 3B, the view angle θ of 30 ° is a stage in which the outputs SA and SB are assigned to the first channel CH1 of the two channels CH1 and CH2, and the output SC is two channels. This is a stage assigned to the second channel CH2 of CH1 and CH2.

  That is, when the view angle θ is 30 °, the outputs SA and SB are transmitted to the channel switching circuit 84 via the packetizing circuit 811, the DC balance adjustment circuit 821, and the P / S conversion circuit 831 shown in FIG. Radio transmission is performed from the channel switching circuit 84 to the S / P conversion circuits 911 and 912 of the receiving circuit 72, respectively. When the view angle θ is 30 °, the output SC is transmitted to the channel switching circuit 84 via the packetizing circuit 812, the DC balance adjustment circuit 822, and the P / S conversion circuit 832 shown in FIG. The signal is wirelessly transmitted from the circuit 84 to the S / P conversion circuit 913 of the reception circuit 72. Subsequently, when the view angle θ advances from 30 ° to 60 °, the stage shown in FIG.

  FIG. 3C shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 60 °. As shown in FIG. 3C, the view angle θ of 60 ° is a stage where the output SA is assigned to the first channel CH1 of the two channels CH1 and CH2, and the channel switching signal U (shown in FIG. 2). ), The output SB is switched from the first channel CH1 to the second channel CH2, and the output SC is assigned to the second channel CH2 of the two channels CH1 and CH2. Subsequently, when the view angle θ advances from 60 ° to 90 °, the stage shown in FIG.

  FIG. 3D shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 90 °. As shown in FIG. 3D, the view angle θ of 90 ° is a stage in which the output SA is assigned to the first channel CH1 of the two channels CH1 and CH2, and the outputs SB and SC are the two channels. This is a stage assigned to the second channel CH2 of CH1 and CH2. Subsequently, when the view angle θ advances from 90 ° to 120 °, the stage shown in FIG.

  FIG. 3E shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 120 °. As shown in FIG. 3E, the view angle θ of 120 ° is a stage in which the output SA is assigned to the first channel CH1 of the two channels CH1 and CH2, and the output SB is the two channels CH1 and CH2. This is a stage assigned to the second channel CH2 of CH2, and is a stage in which the output SC is switched from the second channel CH2 to the first channel CH1 by a channel switching signal U (shown in FIG. 2). Subsequently, when the view angle θ advances from 120 ° to 150 °, the stage shown in FIG.

  FIG. 3F shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 150 °. As shown in FIG. 3F, the view angle θ of 150 ° is a stage in which the outputs SA and SC are assigned to the first channel CH1 of the two channels CH1 and CH2, and the output SB is two channels. This is a stage assigned to the second channel CH2 of CH1 and CH2. Subsequently, when the view angle θ advances from 150 ° to 180 °, the stage shown in FIG.

  FIG. 4A shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 180 °. As shown in FIG. 4A, the view angle θ of 180 ° is a stage where the output SA is switched from the first channel CH1 to the second channel CH2 by the channel switching signal U (shown in FIG. 2), and the output SB Is a stage in which the two channels CH1 and CH2 are assigned to the second channel CH2, and the output SC is a stage in which the two channels CH1 and CH2 are assigned to the first channel CH1. Subsequently, when the view angle θ advances from 180 ° to 210 °, the stage shown in FIG.

  FIG. 4B shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 210 °. As shown in FIG. 4B, the view angle θ of 210 ° is a stage in which the outputs SA and SB are assigned to the second channel CH2 of the two channels CH1 and CH2, and the output SC is two channels. This is a stage assigned to the first channel CH1 of CH1 and CH2. Subsequently, when the view angle θ advances from 210 ° to 240 °, the stage shown in FIG.

  FIG. 4C shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 240 °. As shown in FIG. 4C, the view angle θ of 240 ° is a stage in which the output SA is assigned to the second channel CH2 of the two channels CH1 and CH2, and the channel switching signal U (shown in FIG. 2). ), The output SB is switched from the second channel CH2 to the first channel CH1, and the output SC is assigned to the first channel CH1 of the two channels CH1 and CH2. Subsequently, when the view angle θ advances from 240 ° to 270 °, the stage shown in FIG.

  FIG. 4D shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 270 °. As shown in FIG. 4D, the view angle θ of 270 ° is a stage in which the output SA is assigned to the second channel CH2 of the two channels CH1 and CH2, and the outputs SB and SC are the two channels. This is a stage assigned to the first channel CH1 of CH1 and CH2. Subsequently, when the view angle θ advances from 270 ° to 300 °, the stage shown in FIG.

  FIG. 4E shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 300 °. As shown in FIG. 4E, the view angle θ of 300 ° is a stage in which the output SA is assigned to the second channel CH2 of the two channels CH1 and CH2, and the output SB is the two channels CH1 and CH2. This is a stage assigned to the first channel CH1 of CH2, and is a stage in which the output SC is switched from the first channel CH1 to the second channel CH2 by a channel switching signal U (shown in FIG. 2). Subsequently, when the view angle θ advances from 300 ° to 330 °, the stage shown in FIG.

  FIG. 4F shows outputs SA to SC that the receiving circuit 72 receives on the channels CH1 and CH2 when the view angle θ is 330 °. As shown in FIG. 4F, the view angle θ of 330 ° is a stage in which the outputs SA and SC are assigned to the second channel CH2 of the two channels CH1 and CH2, and the output SB is two channels. This is a stage assigned to the first channel CH1 of CH1 and CH2. Subsequently, when the view angle θ advances from 330 ° to 360 ° (= 0 °), the process returns to the stage shown in FIG.

Further, as shown in FIG. 5, the view angle between 0 ° and 30 ° and the view angle between 180 ° and 210 ° is a period in which the output SA is stable (a stable period of the output SA) T _SA . is there. And between 60 ° view angle of 90 °, and is between 270 ° from 240 ° view angles, the output SB is _{T SB} (stable period of the output _SB) period to stabilize. And between 150 ° from 120 ° view angle, and during the 330 ° from 300 ° view angle, output SC is _{T SC} (stable period of the output _SC) period to stabilize. During these stable periods T _SA , T _SB , and T _SC , the DC balance is adjusted so that packet data is not biased.

However, by increasing the number of channels, that is, the number of m, and rotating the rotating mount 32 (shown in FIG. 1) at a high speed, the stable periods T _SA , T _SB , T _SC can be sufficiently secured. Thus, the DC balance cannot be adjusted. Therefore, the channel switching circuit 84 (shown in FIG. 6) maintains the DC balance without requiring the stable periods T _SA , T _SB , T _SC by synchronizing the channel switching timing with the packet data transmission completion timing. It is something to try.

  Next, details of the configuration of the non-contact transmission / reception unit 34 will be described.

  FIG. 6 is a diagram showing details of the configuration of the non-contact transmitting / receiving unit 34.

  In the configuration shown in FIG. 6, the same members as those in the configuration shown in FIG.

  The P / S conversion circuit 83 shown in FIG. 6 transmits a packet data transmission completion signal V to the channel switching circuit 84. The channel switching circuit 84 performs channel switching at the timing at which the packet data transmission completion signal V is received after the timing at which the channel switching signal U is received.

According to the scanner apparatus 11 and the X-ray CT apparatus 1 according to the present embodiment, the DC balance can be maintained without requiring the stable periods T _SA , T _SB , T _SC for adjusting the DC balance. It is possible to cope with an increase in the number and a high-speed rotation of the rotary mount 32.

(First modification)
FIG. 7 is a diagram illustrating details of the configuration of the first modification of the contactless transmission / reception unit 34 illustrated in FIG. 2.

  FIG. 7 shows a non-contact transmission / reception unit 34A which is a first modification of the non-contact transmission / reception unit 34 shown in FIG. The non-contact transmission / reception unit 34A includes a transmission circuit 71A and a reception circuit 72. The transmission circuit 71A includes a packetizing circuit 81, a DC balance adjustment circuit 82, a channel switching circuit 84A, and a P / S conversion circuit 83A in that order. In FIG. 7, the same members as those shown in FIG.

  The channel switching circuit 84A uses the packet data after the DC balance adjustment transmitted from the DC balance adjustment circuit 82 through the m channels, and uses the m channels according to the view angle of the rotary mount 32 (shown in FIG. 1). Switch the n outputs assigned to. At that time, the channel switching circuit 84A synchronizes the timing of channel switching with the transmission completion timing of packet data by the parallel method.

  The P / S conversion circuit 83A includes 3 (n = 3) P / S conversion circuits 831 to 833. The three P / S conversion circuits 831 to 833 of the P / S conversion circuit 83A respectively convert the 10-bit packet data transmitted from the channel switching circuit 84A into a serial system and wirelessly transmit the data to the reception circuit 72.

  The channel switching circuit 84A shown in FIG. 7 performs channel switching at the timing after the completion of transmission of the packet data to the P / S conversion circuit 83A and when the channel switching signal U is received.

  By adopting the configuration of the non-contact transmission / reception unit 34A shown in FIG. 7, the same effect as the configuration of the non-contact transmission / reception unit 34 shown in FIG. 6 is obtained.

(Second modification)
FIG. 8 is a diagram illustrating details of the configuration of the second modification of the contactless transmission / reception unit 34 illustrated in FIG. 2.

  FIG. 8 shows a non-contact transmission / reception unit 34B which is a first modification of the non-contact transmission / reception unit 34 shown in FIG. The non-contact transmission / reception unit 34B includes a transmission circuit 71B and a reception circuit 72. The transmission circuit 71B includes a packetizing circuit 81, a channel switching circuit 84B, a DC balance adjustment circuit 82B, and a P / S conversion circuit 83B in that order. In FIG. 8, the same members as those shown in FIG.

  The channel switching circuit 84B uses the packet data transmitted by the m channels from the packetizing circuit 81, and uses n packets allocated to the m channels according to the view angle of the rotary mount 32 (shown in FIG. 1). Switch the output of. At that time, the channel switching circuit 84B synchronizes the channel switching timing with the transmission completion timing of the packet data by the parallel method.

  The DC balance adjustment circuit 82B includes 3 (n = 3) DC balance adjustment circuits 821 to 823. The three DC balance adjustment circuits 821 to 823 of the DC balance adjustment circuit 82B generate 10-bit packet data from the 8-bit packet data transmitted from the channel switching circuit 84B, respectively, and are parallel to the P / S conversion circuit 83B. Each method is transmitted.

  The P / S conversion circuit 83B includes 3 (n = 3) P / S conversion circuits 831 to 833. The three P / S conversion circuits 831 to 833 of the P / S conversion circuit 83B respectively convert the 10-bit packet data transmitted from the DC balance adjustment circuit 82B into a serial system and wirelessly transmit the data to the reception circuit 72. .

  The channel switching circuit 84B shown in FIG. 8 performs channel switching at the timing after the completion of transmission of the packet data to the DC balance adjustment circuit 82B and when the channel switching signal U is received.

  By adopting the configuration of the non-contact transmission / reception unit 34B shown in FIG. 8, the same effect as the configuration of the non-contact transmission / reception unit 34 shown in FIG. 6 can be obtained.

  Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1 X-ray CT apparatus 11 Scanner apparatus 12 Image processing apparatus (console)
21 Mounting devices 34, 34A, 34B Non-contact transmission / reception unit 51 X-ray tube 53 X-ray detector 54 DAS
71, 71A, 71B Transmission circuit 72 Reception circuit 81 Packetization circuit 82, 82B DC balance adjustment circuit 83, 83A, 83B P / S conversion circuit 84, 84A, 84B Channel switching circuit 91 S / P conversion circuit

Claims (6)

An X-ray tube that emits X-rays;
An X-ray detector having a plurality of X-ray detection elements and detecting the X-ray;
A converter for digitally converting the output data of the X-ray detector;
A rotating unit that holds the X-ray tube, the X-ray detector, and the conversion unit and rotates with respect to the fixed unit;
The rotation unit includes a channel switching circuit that synchronizes the timing of channel switching according to the view angle with the transmission completion timing of the packet data converted from the output of the conversion unit, and the packet data is transferred from the rotation unit to the fixed unit. A non-contact transmission / reception unit that transmits a non-contact communication method,
A gantry device having   2. The gantry device according to claim 1, wherein the non-contact transmitting / receiving unit transmits the packet data from the rotating unit to the fixed unit by an optical method, an electrostatic coupling method, or a radio wave method as the non-contact communication method. The contactless transmission / reception unit includes a parallel / serial conversion circuit that transmits the packet data to the channel switching circuit in the rotation unit,
The parallel / serial conversion circuit transmits a transmission completion signal of the packet data to the channel switching circuit,
3. The gantry device according to claim 1, wherein the channel switching circuit switches the channel at a timing at which a packet data transmission completion signal is received after a timing at which the channel switching signal is received. The non-contact transmission / reception unit includes a parallel / serial conversion circuit in which the packet data is transmitted from the channel switching circuit to the rotation unit,
3. The gantry according to claim 1, wherein the channel switching circuit switches the channel at a timing after receiving a channel switching signal after the transmission completion timing of the packet data to the parallel / serial conversion circuit. apparatus. The non-contact transmission / reception unit includes a DC balance adjustment circuit to which the packet data is transmitted from the channel switching circuit, a parallel / serial conversion circuit to which the packet data is transmitted from the DC balance adjustment circuit, to the rotation unit, Have
3. The gantry device according to claim 1, wherein the channel switching circuit switches the channel at a timing after receiving a channel switching signal after a transmission completion timing of the packet data to the DC balance adjusting circuit. . The gantry device according to any one of claims 1 to 5,
An image processing device that generates an image based on the output transmitted to the fixed unit;
X-ray CT apparatus.

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