JP4803876B2 - X-ray imaging apparatus and communication method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray imaging apparatus using a solid-state imaging device composed of a plurality of pixels for creating an image, particularly using a cableless imaging unit, and a communication method thereof.
[0002]
[Prior art]
In a conventional X-ray imaging apparatus, an X-ray beam is projected from an X-ray source through an object to be analyzed such as a medical patient, and after the X-ray beam passes through the subject, a screen film cassette, a film autochanger, a CR (Computed radiography) ), FPD (Flat Panel Detector) or the like.
[0003]
In consumer equipment, cameras are in transition from analog film cameras to digital cameras. Also in X-ray photography, a high-resolution solid-state X-ray detector using FPD has been proposed. This is a two-dimensional array using detection elements represented by 3000 to 4000 photodiodes in each dimension. It is configured. Each element creates an electrical signal corresponding to the pixel brightness of the X-ray image projected on the detector. Signals from each detector element are individually read out and digitized, and then image processed, stored and displayed.
[0004]
However, an X-ray digital imaging apparatus using an FPD is difficult to reduce in size using an imaging optical system like a consumer device because of its principle. For example, an X-ray screen film cassette is disclosed in JP-A-6-342099. It is difficult to reduce the size and thickness as proposed in publications. However, the realization is becoming possible as the thickness is reduced and the high reliability technology is improved.
[0005]
Thus, in using a wireless thin X-ray imaging device such as a screen film cassette, solid identification, X-ray synchronization, image transfer, etc. of a plurality of X-ray imaging units that were not problematic in the conventional wired X-ray imaging device This point is newly taken up as a problem.
[0006]
[Problems to be solved by the invention]
When there are a plurality of X-ray imaging units and an operator performs imaging while going back and forth between various X-ray imaging rooms, the synchronization with the X-ray generator is not mistaken for the target X-ray imaging unit. It is necessary to accurately identify the solid state of the X-ray imaging unit.
[0007]
In a system that simply identifies a solid with a unique serial number of an X-ray imaging unit that has been used in the past, problems such as responding to calls from a plurality of X-ray generators to the same X-ray imaging unit occur. Sometimes.
[0008]
An object of the present invention is to provide an X-ray imaging apparatus that facilitates synchronization when using a plurality or types of cableless digital X-ray detection means and a communication method with an X-ray imaging system, and communication thereof. It is to provide a method.
[0009]
[Means for Solving the Problems]
  In order to achieve the above object, an X-ray imaging apparatus according to the present invention comprises:When the X-ray detector for acquiring the X-ray image is detected to approach the predetermined range, the X-ray detector specific information is acquired, and the X-ray detector specific information is acquired when the X-ray detector specific information is acquired. Communication control means for assigning an individual ID key necessary for wireless communication with the line detector;
  Imaging control means for wirelessly controlling the X-ray detector from which the unique information has been acquired by the communication control means, using the individual ID key;It is characterized by having.
[0010]
  Further, the communication method according to the present invention includes:The communication control means acquires the unique information of the X-ray detector by detecting that the X-ray detector that acquires the X-ray image is close to a predetermined range, and obtains the unique information of the X-ray detector. Assigning an individual ID key necessary for wireless communication with the X-ray detector upon acquisition;
  And an imaging control unit that wirelessly controls the X-ray detector from which the unique information has been acquired in the step by using the individual ID key..
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on illustrated embodiments.
FIG. 1 is a block diagram of an X-ray imaging system showing an embodiment, where 1 is an X-ray room, 2 is an X-ray control room, and 3 is a diagnosis / operation room.
[0012]
An X-ray generator 11 that generates X-rays is placed in the X-ray chamber 1. The X-ray generator 11 is an X-ray tube 12 that generates X-rays, and a high-voltage generating power source that drives the X-ray tube 12. 13 includes an X-ray stop 14 for narrowing the X-ray beam generated by the X-ray tube 12 to a desired imaging region. An X-ray detector 16 that detects an X-ray beam that has passed through the subject S and the imaging bed 15 is disposed under the imaging bed 15.
[0013]
The X-ray detector 16 includes a laminated body of a grid 17, a scintillator 18, a photodetector array 19, an X-ray exposure monitor 20, and a driver 21 that drives the photodetector array 19. The grid 17 is provided to reduce the influence of X-ray scattering caused by passing through the subject S, and is composed of an X-ray low-absorption member and a high-absorption member, for example, a stripe structure of A1 and Pb. Yes. At the time of X-ray irradiation, the X-ray detector 16 is based on a setting from an imaging controller in the X-ray control room 2 described later so that moire fringes do not occur due to the lattice ratio between the photodetector array 19 and the grid 17. The grid 17 is vibrated according to the control signal of the driver 21.
[0014]
In the scintillator 18, the host substance of the phosphor is excited (absorbed) by high-energy X-rays, and fluorescence in the visible region is generated by the recombination energy to convert the X-rays into visible light. Its fluorescence is CaWo_FourAnd CdWo_FourFor example, due to the host itself such as CsI: Tl or ZnS: Ag. The photodetector array 19 converts visible light from the scintillator 18 into an electrical signal. In the present embodiment, the scintillator 18 and the photodetector array 19 are configured separately, but the present invention is also applicable to a configuration including a detector that directly converts X-rays into electrons. For example, amorphous Se or PbI₂A radiation (X-ray) detector comprising a light receiving portion such as an amorphous silicon TFT or the like.
[0015]
The X-ray exposure monitor 20 is arranged for the purpose of monitoring the X-ray transmission amount. The X-ray exposure monitor 20 may directly detect X-rays using a crystalline silicon light receiving element or the like, or may detect fluorescence by the scintillator 18. In the present embodiment, the X-ray exposure monitor 20 is composed of an amorphous silicon light-receiving element formed on the back surface of the photodetector array 19, and the hypersight light proportional to the X-ray dose transmitted through the photodetector array 19. Is detected and the light quantity information is transmitted to the imaging controller.
[0016]
In addition, a thin X-ray detector 22 is separately arranged for photographing the extremities and the like, and the thin X-ray detector 22 is connected to the X-ray control room 2 via a relay 23. In FIG. 1, one thin X-ray detector 22 is shown as a representative of a plurality of types of sensors, but the spatial resolution is different, or the size of the thin X-ray detector 22, that is, the size of the imaging region is different. It is possible to exchange and use different ones. The first difference between the X-ray detector 16 and the thin X-ray detector 22 is that the thickness of the thin X-ray detector 22 is about 20 mm or less, comparable to a film screen cassette. It is very different. The thin X-ray detector 22 has no built-in grid 17, a simple power source, has a built-in large-capacity memory of 10 to 20 images, and exchanges image signals and control with the repeater 23 without a cable. There is a feature in that it is possible.
[0017]
Operation is possible with or without the cable 24 connecting the thin X-ray detector 22 and the repeater 23. When the cable 24 is used, image transfer can be performed at a high speed, so that an image is acquired after X-ray imaging. The processing and confirmation operations are achieved in a shorter time, and further, since no charging is required, it is possible to continue shooting for a long time. When the cable 24 is used, it is necessary to use a connector that is easy to attach and detach and has high reliability. In addition to relaying communication with the thin X-ray detector 22, the repeater 23 has a function as an automatic ID assignment, a charger, and a holder when not in use.
[0018]
  In the X-ray control room 2, a system controller 31, an operator interface 32, and a display monitor 33 that control the overall operation of the X-ray imaging system are arranged. The system controller 31 includes the aforementionedImagingDisplay control for displaying various characters and images by controlling the controller 34, for example, an image processor 35 comprising a hard disk array such as RAID, a large-capacity and high-speed storage device 36 for storing processed basic image data, and a monitor 33 The device 37, for example, a large-capacity external storage device 38 such as a magneto-optical disk, the device of the X-ray control room 2 and the device of the diagnosis / operation room 3 are connected, and a photographed image, etc. A LAN board 39 for transfer to the third device is built in.
[0019]
  The interface 32 includes an X-ray exposure request switch, a touch panel, a mouse, a keyboard, a joystick, a foot switch, and the like.OAre used to input various commands to the system controller 31. The instruction content of the operator O includes, for example, imaging conditions such as still images / moving images, X-ray tube voltage, tube current, and X-ray irradiation time, imaging timing, image processing conditions, subject ID, and captured image processing method. There is. The imaging controller 34 is connected to the X-ray generator 11, the imaging bed 15, the driver 21, and the relay 23 placed in the X-ray room 1, and the image processor 35 is connected to the driver 21 of the X-ray room 1 and the relay. The image processing unit 23 is connected to the device 23 and performs image processing on an image by the X-ray imaging system. Examples of the image processing in the image processor 35 include image data correction, spatial filtering, recursive processing, gradation processing, scattered radiation correction, dynamic range (DR) compression processing, and the like.
[0020]
The diagnosis / operation room 3 is connected to the HIS / LIS or the like for instructing the information of the subject S, the imaging method, etc. via the LAN board 39 of the X-ray control room 2. An image processing terminal 41 for supporting image processing and diagnosis, a monitor 42 for displaying an image (moving image / still image) from the LAN board 39, an image printer 43, and a file server 44 for storing image data. Yes.
[0021]
The control signal for each device from the system controller 31 can be generated by an instruction from the operator interface 32 in the X-ray control room 2 or the image processing terminal 41 in the diagnosis / operation room 3. The system controller 31 instructs an imaging condition based on an instruction from the operator O to an imaging controller 34 that controls the sequence of the X-ray imaging system, and the imaging controller 34 based on the instruction instructs the X-ray generator 11. Then, the imaging bed 15 and the X-ray detector 16 are driven to take an X-ray image. When the subject S as a patient lies on the imaging bed 15, the imaging bed 15 is driven according to a control signal from the imaging controller 34, and the direction of the subject S with respect to the X-ray beam from the X-ray generator 11 is changed. Can be changed. The X-ray image signal output from the X-ray detector 16 is supplied to the image processor 35, subjected to image processing designated by the operator O, displayed on the monitor 33, and simultaneously displayed as basic image data in the storage device 36. Stored. Further, the system controller 31 executes re-image processing and the resulting image display, transfer of image data to a device on the network, storage, video display, film printing, and the like based on an instruction from the operator O.
[0022]
When the high voltage generating power source 13 of the X-ray generator 11 applies a high voltage for generating X-rays to the X-ray tube 12 in accordance with a control signal from the imaging controller 34, the X-ray tube 12 generates an X-ray beam. To do. The generated X-ray beam is applied to the subject S through the X-ray stop 14. The X-ray stop 14 is controlled by the imaging controller 34 in accordance with the position where the X-ray beam is to be irradiated. That is, the X-ray diaphragm 14 shapes the X-ray beam so as not to perform unnecessary irradiation with the change of the imaging region.
[0023]
The X-ray beam output from the X-ray generator 11 passes through the subject S lying on the X-ray transmissive imaging bed 15 and the imaging bed 15 and enters the X-ray detector 16. The imaging bed 15 is controlled by the imaging controller 34 so that the X-ray beam is transmitted through different parts or directions of the subject S. Further, when the thin X-ray detector 22 is used, the operator O can make the X-ray beam output from the X-ray generator 11 pass through the subject S and enter the thin X-ray detector 22. The thin X-ray detector 22 and the subject S are adjusted.
[0024]
The grid 17 of the X-ray detector 16 reduces the influence of X-ray scattering caused by passing through the subject S as described above. The imaging controller 34 vibrates the grid 17 during X-ray irradiation so that moire fringes do not occur due to the lattice ratio relationship between the photodetector array 19 and the grid 17. In the scintillator 18, the host substance of the phosphor is excited by absorbing X-rays with high-energy X-rays, and the recombination energy generated at that time generates fluorescence in the visible region. The photodetector array 19 arranged in a stack on the scintillator 18 converts the fluorescence generated by the scintillator 18 into an electrical signal. That is, the scintillator 18 converts the X-ray image into a hyperopic light image, and the photodetector array 19 converts the hyperopic light image into an electrical signal.
[0025]
  The X-ray exposure monitor 20 detects excessive light proportional to the X-ray amount transmitted through the photodetector array 19 and supplies the detected amount information to the imaging controller 34. The imaging controller 34 is based on this X-ray exposure information.High voltage generator13 is controlled to block or adjust X-rays. The driver 21 drives the photodetector array 19 under the control of the imaging controller 34 and reads out pixel signals from each element of the photodetector array 19.
[0026]
Pixel signals output from the X-ray detector 16 and the thin X-ray detector 22 are output to the image processor 35 in the X-ray control room 2. Since the X-ray chamber 1 has a large amount of noise associated with the generation of X-rays, the signal transmission path from the X-ray detector 16 to the image processor 35 needs to have a high noise resistance. Needless to say, it is desirable to use a digital transmission system having an error correction function or a shielded twisted wire pair or an optical fiber by a differential driver.
[0027]
Although details of the image processor 35 will be described later, the display format of the image signal is switched based on a command from the system controller 31, and other operations such as image signal correction, spatial filtering, and recursive processing are performed in real time. Processing, scattered radiation correction, DR compression processing, and the like can be executed. The image processed by the image processor 35 is displayed on the screen of the monitor 33. At the same time as the real-time image processing, basic image information that has undergone only image correction is stored in the storage device 36. Further, based on an instruction from the operator O, the image information stored in the storage device 36 is reconstructed so as to satisfy a predetermined standard of, for example, Image Save & Carry (IS & C), and then the external storage device 38 and the file. It is stored in a hard disk or the like in the server 44.
[0028]
The apparatus in the X-ray control room 2 is connected to a LAN (or WAN) via the LAN board 39. Of course, a plurality of X-ray imaging systems can be connected to the LAN. The LAN board 39 outputs image data in accordance with a predetermined protocol such as Digital Imaging and Communication in Medicine (DICOM). By displaying high-resolution still images and moving images of X-ray images on the screen of the monitor 42 connected to the LAN (or WAN), a real-time remote diagnosis by a doctor can be performed almost simultaneously with X-ray imaging.
[0029]
  FIG. 2 shows an example of an equivalent circuit of the structural unit of the photodetector array 19. One element includes a photodetecting portion 51 and a switching TFT (thin film transistor) 52 for controlling charge accumulation and reading, and is generally formed of amorphous silicon (a-Si) on a glass substrate. The light detection unit 51 further includes a parallel circuit of a photodiode 51a and a capacitor 51b, and charges due to the photoelectric effect are obtained.Current source in sensor53. The capacitor 51b may be a parasitic capacitance of the photodiode 51a or an additional capacitor that improves the dynamic range of the photodiode 51a. The cathode of the photodiode 51a is connected to a bias power supply 54 via a bias wiring Lb that is a common electrode (D electrode). The anode of the photodiode 51 a is connected from the gate electrode G to the capacitor 55 and the charge readout preamplifier 56 through the switching TFT 52. The input of the preamplifier 56 is connected to the ground via a reset switch 57 and a signal line bias power source 58.
[0030]
  First, the switching TFT 52 and the reset switch 57 are temporarily turned on, the capacitor 51b is reset, and the switching TFT 52 and the reset switch 57 are turned off. Thereafter, X-rays are generated and exposed to the subject S. X-ray image transmitted through subject S is scintillator18Is converted into a visible light image, and the photodiode 51a becomes conductive due to the visible light image, and discharges the capacitor 51b. The switching TFT 52 is turned on, and the capacitor 51b and the capacitor 55 are connected. As a result, the information on the discharge amount of the capacitor 51b is also transmitted to the capacitor 55. Further, the preamplifier 56 amplifies the voltage by the accumulated charge of the capacitor 55 or the charge-voltage conversion by the capacitor 59 shown by the dotted line and outputs it to the outside.
[0031]
FIG. 3 is an equivalent circuit of the photodetector array 19 having a two-dimensional array of photoelectric conversion elements configured by extending the photoelectric conversion elements shown in FIG. 2 in two dimensions. Since the two-dimensional read operation is the same in the above two types of equivalent circuits, FIG. 3 shows the equivalent circuit shown in FIG. The photodetector array 19 is composed of about 2000 × 2000 to 4000 × 4000 pixels, and the array area is about 200 mm × 200 mm to 500 mm × 500 mm. In FIG. 3, the photodetector array 19 is composed of 4096 × 4096 pixels, the array area is 430 mm × 430 mm, the size of one pixel is about 105 × 105 μm, and 4096 pixels arranged in the horizontal direction are 1 The block has a two-dimensional configuration in which 4096 blocks are arranged in the vertical direction.
[0032]
In FIG. 3, the photodetector array 19 composed of 4096 × 4096 pixels is constituted by one substrate, but it is needless to say that four photodetector arrays having 2048 × 2048 pixels may be combined. In this case, the labor for assembling the four photodetector arrays is generated, but the yield of each photodetector array is improved, so that there is an advantage that the yield is improved as a whole.
[0033]
As described with reference to FIG. 2, one pixel includes one light detection unit 51 and a switching TFT 52. The photoelectric conversion elements PD (1, 1) to (4096, 4096) correspond to the light detection unit 51, and the transfer switches SW (1, 1) to (4096, 4096) correspond to the switching TFT 52. The gate electrode G of the photoelectric conversion element PD (m, n) is connected to a common column signal line Lcm for the column via a corresponding switch SW (m, n). For example, the photoelectric conversion elements PD (1, 1) to (4096, 1) in the first column are connected to the first column signal line Lc1, and the common electrode D of each photoelectric conversion element PD (m, n) is All are connected to the bias power supply 54 via the bias wiring Lb.
[0034]
The control terminals of the switches SW (m, n) in the same row are connected to a common row selection line Lrn. For example, the switches SW (1, 1) to (1,4096) in the first row are connected to the row selection line Lr1, and the row selection lines Lr1 to 4096 are connected to the imaging controller 34 via the line selector 61. . The line selector 61 decodes the control signal from the imaging controller 34 and determines which line of the photoelectric conversion element PD should read out the signal decoder 62, and 4096 elements that are opened and closed according to the output of the address decoder 62. Switch element 63. With this configuration, the signal charge of the photoelectric conversion element PD (m, n) connected to the switch SW (m, n) connected to the arbitrary line Lrn can be read. The simplest one of the line selector 61 may be constituted simply by a shift register used in a liquid crystal display or the like.
[0035]
The column signal lines Lc1 to 4096 are connected to a signal readout circuit 71 controlled by the imaging controller 34. The signal readout circuit 71 includes reset switches 73-1 to 4096 for resetting the column signal lines Lc1 to 4096 to the reset reference potential power source 72, and a preamplifier 74-1 for amplifying the signal potentials from the column signal lines Lc1 to 4096, respectively. To 4096, S / H (sample hold) circuits 75-1 to 4096 for sampling and holding the outputs of the respective preamplifiers 74-1 to 4096, and outputs of the S / H circuits 75-1 to 4096 are multiplexed on the time axis. An analog multiplexer 76 and an A / D converter 77 that digitizes the analog output of the multiplexer 76 and supplies it to the image processor 35 are provided.
[0036]
In the photodetector array shown in FIG. 3, 4096 × 4096 pixels are divided into 4096 columns by column signal lines Lc1 to 4096, and signal charges of 4096 pixels per row are simultaneously read, and each column signal line Lc1 to Lc1 is read. 4096, preamplifiers 74-1 to 4096 and S / H circuits 75-1 to 4096 are transferred to the analog multiplexer 76 where they are time-axis multiplexed and sequentially converted into digital signals by the A / D converter 77. To do.
[0037]
In FIG. 3, the signal readout circuit 71 is illustrated as having only one A / D converter 77, but in reality, A / D conversion is simultaneously performed in 4 to 32 systems. This is because it is required to shorten the reading time of the image signal without unnecessarily increasing the analog signal band and the A / D conversion rate. The signal charge accumulation time and the A / D conversion time are closely related. If A / D conversion is performed at high speed, the bandwidth of the analog circuit becomes wide, and it becomes difficult to achieve a desired high S / N. Usually, it is required to shorten the reading time of the image signal without unnecessarily increasing the A / D conversion speed. Many A / D converters 77 may perform A / D conversion on the output of the multiplexer 76, but the cost increases as the number of A / D converters 77 increases. Therefore, an appropriate number of A / D converters 77 are used in consideration of the above points.
[0038]
Since the X-ray irradiation time is about 10 to 500 msec, it is appropriate to shorten the capture time or charge accumulation time for the entire screen on the order of 100 msec or often shorter. For example, in order to drive all the pixels sequentially and capture an image in 100 milliseconds, if the analog signal band is set to about 50 MHz and A / D conversion is performed at a sampling rate of 10 MHz, for example, at least four A / D systems A converter 77 is required. In the present embodiment, A / D conversion is simultaneously performed in 16 systems, and the outputs of the 16 systems A / D converter 77 are input to the corresponding memory (FIFO and the like) (not shown) of 16 systems. By selecting and switching the memory, image data corresponding to one continuous scanning line is transferred to the image processor 35.
[0039]
FIG. 4 is a schematic timing chart of sensor readout. A description will be given of two-dimensional driving in the case of taking a still image by one X-ray irradiation in conjunction with FIG. 4, (a) is an X-ray exposure request control signal, (b) is the X-ray exposure state, (c) is the current of the current source 53 in the sensor, and (d) is the row selection line Lrn. Control state (e) schematically represents an analog input to the A / D converter 77.
[0040]
All the column signal wirings Lc are connected to the reset reference potential power supply 72 while the bias wirings remain at the bias value Vs during photoelectric conversion, and the column signal lines are reset. Thereafter, a positive voltage Vgh is applied to the row selection wiring Lr1, the switches SW (1, 1) to (1,4096) are turned on, and the gate electrodes G of the photoelectric conversion elements in the first column are reset to Vbt. Next, the row selection wiring Lr1 is set to the positive voltage Vgl, and the switches SW (1, 1) to (1, 4096) are turned off. When the selection of rows is sequentially repeated and all the pixels are reset, the preparation for photographing is completed.
[0041]
The above operation is the same as the signal charge reading operation, and there is no difference whether or not the signal charge is taken in. Therefore, this reset operation is hereinafter referred to as “empty reading”. During this idle reading operation, it is possible to simultaneously set all the row selection lines Lr to Vgh. However, in this case, when the read preparation is completed, the signal line potential greatly deviates from the reset voltage Vbt. It is difficult to get a signal. In the above-described example, the row selection wiring Lr is reset from 1 to the column signal wiring 4096, but can be reset in any order by the control of the driver 21 based on the setting of the imaging controller 34. . The idle reading operation is repeated to wait for an X-ray exposure request, and when an exposure request is generated, the idle reading operation is performed again in preparation for image acquisition to prepare for the X-ray exposure. When preparation for image acquisition is complete, X-rays are emitted according to instructions from the imaging controller 34.
[0042]
After the X-ray exposure, the signal charge of the light detection unit 51 is read out. First, Vgh is applied to the row selection wiring Lr for a certain row (for example, Lr1) of the photoelectric conversion element PD, and the accumulated charge signal is output to the signal wirings Lc1 to 4096. Signals for 4096 pixels are read simultaneously from the column signal wirings Lc1 to 4096, one column at a time. Next, Vgh is applied to a different row selection line Lr, for example, Lr2, and the accumulated charge signal is output to the signal lines Lc1 to 4096. Signals for 4096 pixels are read simultaneously from the column signal wirings Lc1 to 4096, one column at a time. By repeating this operation sequentially for the column signal wiring 4096, all image information is read out.
[0043]
During the above operation, the charge accumulation time of each sensor is from the time when the reset operation is completed, that is, from the time when the switching TFT 52 is turned off at the time of idle reading until the time when the TFT 52 is turned on for charge reading. For this reason, the accumulation time and time are different for each row selection line.
[0044]
After reading out the X-ray image, a correction image is acquired. This is for use in correction of an X-ray image, and is correction data necessary for acquiring a high-quality image. The basic image acquisition method is the same except that X-rays are not exposed. The charge accumulation time is the same when reading the X-ray image and when reading the correction image. Further, when high-resolution image information is not required or when it is desired to increase the image data capture speed, it is not always necessary to capture all image information. Sets driving instructions for thinning, pixel averaging, and region extraction to the driver 21.
[0045]
In order to perform thinning, first, the row selection wiring Lr1 is selected, and when a signal is output from the column signal wiring Lc, for example, one column is set so that n of Lc2n-1 (n: natural number) is increased from 0 to 1 at a time. Is read out, and when selecting a subsequent row, the row selection wiring Lr2m-1 (m: natural number) is incremented by 1 from 1 and the signal of one row is read out. In this example, the number of pixels is thinned to ¼, but the driver 21 thins the number of pixels to 1/9, 1/16, etc. in accordance with the setting instruction of the imaging controller 34.
[0046]
For pixel averaging, by simultaneously applying Vgh to the row selection lines Lr2m and Lr2m + 1 during the above-described operation, the TFTs 2m and 2n and the TFTs 2m + 1 and 2n are simultaneously turned on, and analog addition of two pixels in the column direction is performed. Is possible. This is not limited to the addition of two pixels, but represents that an analog addition of a plurality of pixels in the column signal wiring direction can be easily performed. Further, for the addition in the row direction, the adjacent pixels (Lc2n and Lc2n + 1) are digitally added after A / D conversion output, thereby obtaining an addition value of 2 × 2 square pixels together with the above-described analog addition. be able to.
[0047]
This makes it possible to read data at high speed without wasting the irradiated X-rays. As another method for reducing the total number of pixels and aiming for high speed, there is a method for limiting the image capture area. This is because an area required by the operator O is input from the operator interface 32, and based on this, the imaging controller 34 outputs an instruction to the driver 21, and the driver 21 changes the data capture range to detect light. The device array 19 is driven.
[0048]
In the present embodiment, in the high-speed capture mode, 1024 × 1024 pixels are captured at 30 F / S. That is, the entire area of the photodetector array 19 is subjected to addition processing of 4 × 4 pixels and thinned out to 1/16, and in the smallest range, imaging is performed without thinning out in the 1024 × 1024 region. In this way, a digital zoom image can be obtained by imaging.
[0049]
FIG. 5 is a timing chart including the imaging operation of the X-ray detector 16. An imaging request signal (f), a ready signal (g), an actual X-ray exposure state (h) to the operator interface 32, and an imaging request signal (from the imaging controller 34 to the driver 21 based on an instruction from the operator O) i) an imaging ready signal (j) of the X-ray detector 16, a drive signal (k) of the grid 17, a power control signal (l) in the X-ray detector 16, a driving state of the X-ray detector 16, particularly light The charge readout operation from the detector array 19 (m), the image data transfer state, and the image processing and display state (n) are shown.
[0050]
Until there is a detector preparation request or an imaging request from the operator O, the driver 21 stands by in a power control OFF state as shown in (l). Specifically, in FIG. 3, the potentials of the row selection line Lr, the column signal line Lc, and the bias wiring Lb are kept at the same potential, particularly the ground potential by a switch (not shown), and no bias is applied to the photodetector array 19. Further, the potential of the row selection line Lr, the column signal line Lc, and the bias wiring Lb may be maintained at the ground potential by cutting off the power including the signal readout circuit 71, the line selector 61, and the bias power supply 54.
[0051]
In response to an imaging request signal (f) from the first switch that starts normal rotor rotation for preparation of imaging for the operator interface 32 of the operator O, the imaging controller 34 controls the X-ray generator 11 (g). ) And an instruction to shift to the imaging preparation state is output to the X-ray detector 16. Upon receiving the instruction, the driver 21 applies a bias to the photodetector array 19 and repeats the idle reading Fi. For example, when the X-ray detector 16 requires a predetermined time of several seconds or more to prepare for imaging, the preparation instruction of the X-ray detector 16 is used. It is an instruction to start.
[0052]
In this case, the operator O does not need to consciously issue an imaging preparation request instruction to the X-ray detector 16. That is, when subject information, imaging information, etc. are input to the operator interface 32, the imaging controller 34 interprets this as a detector preparation request instruction, and puts the X-ray detector 16 in the detector preparation state. It may be migrated.
[0053]
In the detector preparation state, after the idle reading in the photoelectric conversion mode, the dark reading Fi is set at predetermined intervals in order to avoid that dark current is gradually accumulated in the light detection unit 51 and the capacitor 51b is held in a saturated state. repeat. While there is an imaging preparation request from the operator O, driving that is performed during a period when an actual X-ray exposure request is not generated, that is, driving that repeats idle reading Fi performed in the detector preparation state at a predetermined time interval T1. Hereinafter, it is referred to as “idling driving”, and the period of the detector preparation state in which idling driving is performed is referred to as “idling driving period”. The duration of the idling drive period is undefined in actual use. Therefore, the time interval T1 is set for the normal photographing operation in order to minimize the reading operation that places a load on the photodetector array 19, particularly the switching TFT 52. Longer than the normal read drive Fr, the idling dedicated idle read drive Fi in which the on time of the TFT 52 is shorter than the normal read drive Fr is performed.
[0054]
The driving of the X-ray detector 16 at the time of X-ray image acquisition mainly includes two image acquisitions. As shown in (m), one is X-ray image acquisition driving, and the rest is correction dark image acquisition driving. Each drive is generally the same, and the main difference is whether or not there is an operation in which X-ray exposure is performed. Further, each drive is composed of three parts: an imaging preparation sequence, charge accumulation (exposure window), and image readout.
[0055]
The X-ray image acquisition will be described below in sequence. The imaging controller 34 causes the X-ray generator 11 and the X-ray detector to detect the imaging request signal (f) from the operator O to the operator interface 32 by the second switch. The photographing operation is controlled while being synchronized with 16. In accordance with the imaging request signal (f), the imaging request signal (f) is asserted to the X-ray detector 16 at the timing indicated by the X-ray exposure request signal (i). In response to the imaging request signal (f), the driver 21 performs predetermined imaging preparation sequence driving as shown in the imaging driving state of (m). Specifically, when refresh is necessary, refresh is performed, and the dedicated empty reading Fp for the imaging sequence is performed a predetermined number of times and the charge accumulation state dedicated empty reading Fpf is performed, and the charge accumulation state (imaging window: T4) Transition to.
[0056]
At this time, the number of idle readings Fp for the imaging sequence and the time interval T2 are performed based on values set in advance from the imaging controller 34 prior to the imaging request. According to the request of the operator O, whether the operability is important or the image quality is important, or the optimum driving is automatically selected and switched depending on the imaging part. In the period T3 from the exposure request to the completion of the imaging preparation, it is required for practical use that the required time is short. For this purpose, the imaging preparation sequence dedicated idle reading Fp is performed. Furthermore, when an exposure request is generated from any state of idling driving, the operability can be improved by shortening the period T3 from the exposure request to completion of imaging preparation by immediately entering the imaging preparation sequence driving. Plan.
[0057]
Now, the driver 21 starts moving the grid 17 in synchronism with the preparation of the detector array 19 for imaging. This is because the grid is imaged in an optimal moving state in synchronization with the actual X-ray exposure of (h). Also in this case, the driver 21 operates at the optimum grid movement start timing and the optimum grid movement speed set by the imaging controller 34.
[0058]
When the X-ray detector 16 is ready for imaging, the driver 21 returns an X-ray detector ready signal (j) to the imaging controller 34, and the imaging controller 34 based on the transition of this signal. The X-ray generator 11 is asserted as an X-ray generation request signal. The X-ray generator 11 generates X-rays while the X-ray generation request signal of (h) is given. When a predetermined amount of X-rays is generated, the imaging controller 34 negates the X-ray generation request signal in (h) and negates the X-ray imaging request signal in (i), thereby acquiring an image in the X-ray detector 16. Notify timing.
[0059]
Based on this timing, the driver 21 immediately stops the grid 17 and starts the operation of the signal readout circuit 71 that has been in the standby state. After the grid stationary time and a predetermined standby time for stabilization of the signal readout circuit 71, image data is read from the X-ray detector array 19 based on the driver 21, and a raw image is acquired by the image processor 35. When the transfer is completed, the driver 21 shifts the reading circuit 71 to the standby state again.
[0060]
Subsequently, the X-ray detector 16 acquires a corrected image. That is, the imaging sequence for the previous imaging is repeated, a dark image without X-ray irradiation is acquired, and the correction dark image is transferred to the image processor 35. At this time, the imaging sequence may differ slightly in X-ray exposure time, etc. at each imaging, but by reproducing the exact same imaging sequence including that and acquiring a dark image, a higher quality image can be obtained. Is obtained. However, the operation of the grid 17 is not limited to this, and is kept stationary in order to suppress the influence of vibration when acquiring a dark image. After the dark image is acquired, the grid 17 is initialized at a predetermined timing that does not affect the image quality.
[0061]
  FIG. 6 is a block circuit configuration diagram of the image processor 35. Signals from the driver 21 are divided into two by a multiplexer 81, each for an X-ray image.flameMemory 82, dark imageforConnected to the frame memory 83, and the outputs of these memories 82 and 83 are connected to the offset correction circuit 84. The output of the offset correction circuit 84 is gainCorrection circuit85, a defect correction circuit 86, and an image processing circuit 87, and is connected to an external display controller 37. A gain correction frame memory 88 is connected to the gain correction circuit 85.
[0062]
In FIG. 6, the X-ray image acquired in the X-ray image acquisition frame Frxo frame is stored in the X-ray image frame memory 82 via the multiplexer 81, and subsequently the correction acquired in the correction image acquisition frame Frno frame. Similarly, the image is stored in the dark image frame memory 83 via the multiplexer 81. After the dark image is stored, the offset correction circuit 84 performs, for example, Frxo-Frno offset correction. Subsequently, the gain correction circuit 85 performs gain correction of (Frxo-Frno) / Fg, for example, using the gain correction data Fg acquired in advance and stored in the gain correction frame memory 88. The data transferred to the defect correction circuit 86 continuously interpolates the image so as not to cause a sense of incongruity in the insensitive pixels or the joints of the X-ray detector 16 composed of a plurality of panels, and the X-ray detector 16. The sensor-dependent correction process derived from is completed.
[0063]
In the present embodiment, the image processor 35 is configured in the system controller 31, but the image processing function that greatly depends on the above-described photodetector array 19 is applied to the X-ray detector 16 and the thin X-ray detector 22. You may comprise so that it may incorporate. Then, after performing general image processing such as gradation processing, frequency processing, and enhancement processing by other image processing circuits 87, the processed data is transferred to the display controller 37, and is sent to the monitor 33. Display the captured image.
[0064]
  FIG. 7 shows a block circuit configuration diagram of the thin X-ray detector 22 and the repeater 23. In the thin X-ray detector 22, an MPU 91, a data drive control unit 92, an image memory 93, a wireless communication module 94, and an external connection connector are shown. 95 and a power source 96 are provided. The MPU 91 controls various operations and states in the thin X-ray detector 22, and an individual communication key register that stores an individual communication key (described later) in the MPU 91.97And validity period counter that monitors the validity period of individual ID keys98Is configured by software.
[0065]
The function of the data drive control unit 92 performs logic level control such as communication control at the physical layer level, drives the photodetector array 19 based on an instruction from the MPU 91, and outputs an analog output from the photodetector array 19 based thereon. Is taken in by an AD converter not shown, and the taken digital image is written in the image memory 93. Further, the reduced image data is output to the repeater 23 via the wireless communication module 94, and all the image data is output to the repeater 23 via the connector 95 when mechanically connected. In addition, when there is a margin in the shooting interval, all image data may be transferred using wireless communication. However, since communication for shooting operation is given priority over image transfer operation, image transfer is often performed. Interrupted. For this reason, it is necessary to have an image division transmission, an image retransmission function, and the like.
[0066]
The image memory 93 includes volatile memories of about 2 to 3 images, such as SRAM and DRAM (particularly SDRAM), and about 20 non-volatile memories such as a flash ROM and a memory-backed RAM. In some cases, the nonvolatile memory may be formed of a removable medium. In that case, the nonvolatile memory has a removable mechanical structure.
[0067]
The power source 96 is a rechargeable capacity power source for supplying power to all parts in the thin X-ray detector 22 by wiring not shown in the figure. It is formed of a double layer capacitor. The capacity is set such that continuous shooting of about 20 sheets or less is possible. At this time, for example, the capacity is set to about 400F. In some cases, the power source 96 may be constituted by a secondary battery or the like. However, the battery needs to be replaced, and there are more restrictions in use such as requiring a charging time compared to the electric double layer capacitor.
[0068]
  In the repeater 23, the MPU 101,imageA data flow controller 102, an image memory 103, and a charger 104 are provided. The MPU 101 controls the repeater 23 and controls a plurality of thin X-ray detectors 22. Inside the MPU 101 are individual communication key registers 105 for storing the number of thin X-ray detectors 22 to which individual communication keys to be described later can be connected, an effective period counter 106 for monitoring the effective period of the individual ID key, and The communication key counter 107 for assigning the unique communication key is configured by software.
[0069]
  The image data flow controller 102 controls transfer of the X-ray image sent from the thin X-ray detector 22 based on an instruction from the MPU 101. Image memory103Is a volatile memory and a frame buffer memory composed of DRAM. In particular, during wireless communication or the like, there is a possibility that error correction or image resending may occur, and if data begins to flow to the system controller 31 before image transfer is completed, control within the system controller 31 is possible. Therefore, the image memory 103 is required to transfer the image to the system controller 31 after the image transfer between the thin X-ray detector 22 and the repeater 23 is completed. The charger 104 must ensure a capacity sufficient to rapidly charge the power source 96 of the thin X-ray detector 22, for example, a capacity capable of charging a capacity of about 500 mWh in about 30 seconds.
[0070]
In FIG. 7, a wavy arrow between the thin X-ray detector 22 and the repeater 23 represents wireless communication, and a dotted line represents a wired connection or a direct connection by a connector. When a wired connection or a connector connection is made, the wireless module stops. The connector 95 must be a connector that is easy to attach and detach and highly reliable. Furthermore, it is not always necessary to provide a clear connector 95 by exchanging data, including a charging operation by the charger 104, by electromagnetic coupling using a transformer or the like. However, in this case, a mechanism for detecting the proximity of the thin X-ray detector 22 and the repeater 23 is required in addition to extending charging time and transfer time.
[0071]
FIG. 8 shows an example of the display screen of the operator interface 32. The display screen 111 includes a reduced image display area 112 of the acquired image, an X-ray detector 16 or an imaging target corresponding to the thin X-ray detector 22. A region 113 and an effective X-ray detector display area 114 exist. When the thin X-ray detector 22 is used, re-processing is performed based on the image transferred by the previous wireless communication to display an image. In the effective X-ray detector display area 114, an icon representing the X-ray detector 16 or the thin X-ray detector 22 in which the system controller 31 can be controlled is displayed.
[0072]
FIG. 9 shows an example of the effective X-ray detector display area 114. In each icon 121, the uppermost row represents the type of the X-ray detector, the middle row represents the imaging area, and the lower row represents the pixel size. In the case of (a), the saddle type X-ray detector 22 is identified by the system controller 31, and the fact that it is further gray indicates that the saddle type X-ray detector 16 is currently controlled. It represents something. In addition, the fact that there are three dotted line icons 121 in (a) indicates that the current system setting can register up to three thin X-ray detectors 22. In this case, the individual communication key register 105 and the validity period counter 106 in the MPU 101 in the repeater 23 are also set to be prepared in units of three.
[0073]
  When the thin X-ray detector 22 is newly connected to the repeater 23 in the state of (a),bThe X-ray detector 22 in which the system controller 31 is in a controllable state is added as a new icon 121 as shown in FIG.b) Represents an icon 121 written as “cassette”. When the system controller 31 recognizes the thin X-ray detector 22, the system controller 31 automatically changes the thin X-ray detector 22 as the current control target. The user (bWhen the user wants to perform shooting with the supine type from the state of), the control object can be changed to the supine type by selecting the supine type icon by touch panel or mouse operation. At this time, the display of the imaging target region 113 is automatically changed to the imaging target site 113 corresponding to the X-ray detector 22 to be controlled.
[0074]
A method of exchanging data and control between the plurality of types of thin X-ray detectors 22 and the repeaters 23 will be described with reference to FIGS. 9, 10, and 11. When a plurality of thin X-ray detectors 22A (cassette / large four / □ 100 μm), 22B (cassette / half-cut / □ 160 μm), etc. exist as in procedure 1 of FIG. If it is going to do, it will become difficult for the thin X-ray detector 22 side to know which thin X-ray detector 22 is used to perform X-ray imaging. The thin X-ray detector information is stored in the system controller 31 including the repeater 23 in advance, and the ID of the thin X-ray detector 22 is stored in advance, and the ID is used unilaterally from the system controller 31 side. The ID of the X-ray detector 22 may be output. In this case, for example, in a hospital having a plurality of X-ray chambers 1, when a large number of thin cassettes are used in common, the operator O It becomes necessary to check and input the number of the thin X-ray detector 22 to be used.
[0075]
  In the present embodiment, the thin X-ray detector 22A to be used is set in the repeater 23 as in procedure 1 in FIG. 10 before imaging. The state of the effective X-ray detector display area 114 is as shown in FIG.b), That is, one saddle type X-ray detector 16 and one cassette type thin X-ray detector 22B are controllable. At the time of step 2 in FIG. 10, the repeater 23 first acquires the unique information of the thin X-ray detector 22A and transmits it to the system controller 31 as shown in FIG. Display its presence.
[0076]
  Next, the MPU 101 in the repeater 23 assigns a mutual communication key to the thin X-ray detector 22A based on a predetermined rule. That is, the MPU 101 first creates a communication key, and the two MPUs 101 and91Communication key register 105, 96The created communication key is stored, and at the same time, the validity period counter 106 corresponding to the communication key is initialized. As the communication key, for example, an X-ray generator 11 or simply an ID number of the repeater 23 and a serial ID for identifying the thin X-ray detector 22 may be assigned as the communication key. In some cases, a plurality of X-ray generators 11 are installed in the X-ray chamber 1. Even in this case, X-rays are generated from only one X-ray generator 11 at the same time. It is desirable to create a communication key based on the ID number of the system controller 31 or the repeater 23 that controls the plurality or a plurality of X-ray generators 11 rather than the serial ID of 11.
[0077]
FIG. 12 shows an example of a serial ID. The communication key counter 107 in FIG. 12H is a counter in the MPU 101 that is incremented by +1 every time a communication key is allocated. Also, in order to make sure that there is no duplication when assigning IDs, cableless communication is attempted to check that there is no response. Of course, at the time of this check, the thin X-ray detector 22A still allocated does not respond to the check question. If there is an overlap, the next ID is assigned and the above assignment work is repeated until there is no problem. The communication key can be configured to be used only between the thin X-ray detector 22 and the repeater 23, and the allocation timing is triggered when the thin X-ray detector 22 is set on the repeater 23. Start as.
[0078]
In step 2 of FIG. 10, the thin X-ray detector 22 is charged in addition to the ID assignment. As described above, when a plurality of thin X-ray detectors 22 are used, it is not always connected to the repeater 23 except during imaging, so there is a high possibility that they are left in a discharged state. For this reason, it is fully considered that rapid charging is required, and a power source capable of rapid charging such as an electric double layer capacitor is preferable to a secondary battery.
[0079]
When actually performing X-ray imaging, the operator O removes the thin X-ray detector 22 from the repeater 23 and sets the X-ray generator 11, the target to be imaged, as shown in step 3 of FIG. The positions of the specimen S and the thin X-ray detector 22 are adjusted. When the operator O selects the thin X-ray detector 22A displayed on the operator interface 32, the relay 23 wirelessly transmits the information to the thin X-ray detector 22A. At this time, by using the previously assigned communication key, only the thin X-ray detector 22A is activated without bringing the thin X-ray detector 22B and the thin X-ray detector 22 in the adjacent room into operation. Can be. A communication technique using an ID such as a communication key is very common. For example, after simply specifying a communication partner using a communication key, packet communication up to a predetermined bit length or a predetermined delimiter is performed.
[0080]
When the operation state is reached, the thin X-ray detector 22 emits a buzzer sound at the same time as the selection display LED or the like is lit. Further, by selecting the icon 121 at a timing desired by the operator O, the thin X-ray detector 22 emits a buzzer sound or the like, and the thin X-ray detector 22 used by the operator O is not wrong. Can also be confirmed. Further, the thin X-ray detector 22 is provided with a selection switch (not shown), and by pressing the selection switch, the thin X-ray detector 22 with the switch pressed is forcibly activated. It is also possible.
[0081]
At this time, since the selection state of the thin X-ray detector 22 is displayed on the operator interface 32 so that the icon 121 changes to gray, the thin X-ray detector 22 held by the operator O is displayed on the operator interface. It is possible to confirm which button on 32 corresponds to or is not listed there. Further, it may be configured to check whether or not the target thin X-ray detector 22 exists in front of the X-ray generator 11 using radio waves or the like.
[0082]
Thereafter, the X-ray imaging can be performed while the X-ray synchronization as shown in FIG. Here, the X-ray imaging request signal of (i), the X-ray detector ready signal of (j), and the X-ray exposure signal of (h) only have their transition timings in order to minimize imaging errors. It is desirable to always keep sending during the assertion period, rather than communicating with each other. In some cases, a modulated sound wave or the like may be used as these signals.
[0083]
Further, at the time of X-ray exposure, the thin X-ray detector 22 receives information on the exposure itself, for example, the total number of exposures, imaging information, for example, a region to be imaged, and subject information, for example, a subject ID, from the X-ray generator 11. It may be configured to be acquired at the time of X-ray exposure. The acquisition timing is preferably before X-ray exposure, and the X-ray detector ready signal in (j) should not be asserted until acquisition is completed. By adding the exposure information, imaging information, and subject information to the image header and performing data processing based on the header information, the subsequent captured image is not shifted from the subject information input.
[0084]
When X-ray imaging is completed, it is difficult to transfer all captured images within a short time as in the cable connection state due to transfer speed limitations in the cableless state. For this reason, the reduced image is transferred first, and an image that can be confirmed whether or not there is an obvious imaging error is displayed in the reduced simplified image display area 112 of the previous acquired image. All captured images are stored in a built-in memory in the thin X-ray detector 22. The thin cassette needs only to have about 20 or less non-volatile image memories and a power supply that can withstand the photographing.
[0085]
For further imaging, the thin X-ray detector 22 is replaced. This is because the number of images to be captured per subject is normally 20 or less, and the captured image data is collected quickly. That is, the state of the procedure 3 shown in FIG. 10 is not continued for a long time, and is repeated from the procedure 1 every time the subject S is changed. In order to proceed more quickly, a thin X-ray detector 22B having the same specifications as the thin X-ray detector 22A is prepared and used alternately. It is possible to move to imaging of the subject S. In FIG. 10, up to two thin X-ray detectors 22 are set in the repeater 23, but it goes without saying that this number may be increased.
[0086]
When returning from step 3 to step 1, once the thin X-ray detector 22A, to which the communication key has been assigned, is set or connected to the repeater 23 within a predetermined effective period of 1 hour, for example, the conventional communication The key remains valid as it is in the communication key register 105, and the corresponding valid period counter 106 is initialized to measure the previous valid period.
[0087]
However, even within the effective period, if the icon 121 corresponding to the thin X-ray detector 22 has already been deleted from the previous effective X-ray detector display area 114 by a predetermined procedure, confusion is avoided. Therefore, a new communication key is allocated, and the icon 121 is displayed again in the effective X-ray detector display area 114. Conversely, for example, the communication key of the thin X-ray detector 22 that does not return to the repeater 23 within a predetermined time of 1 hour becomes invalid, and, for example, the third icon 121 from the top of FIG. 9 (e) → (f). Will be changed to a dotted line icon. The invalid communication key, the corresponding communication key register 105 and the valid period counter 106 are opened for the thin X-ray detector 22 newly connected to the repeater 23.
[0088]
Of course, if the same communication key is assigned immediately after it becomes invalid, it may cause a recognition error. Therefore, if there are about 128 communication keys, for example, by the ID counter 107 per relay 23, FIG. As shown in Fig. 5, the time interval without any problem in system operation can be obtained by using them sequentially. The thin X-ray detector 22 and the repeater 23 forget the communication key when the effective period of the communication key by the effective period counter 106 times out, that is, clear the communication key register 105. The thin X-ray detector 22 having cleared the communication key has no problem if it starts again from the procedure 1. Furthermore, even if there is uncollected image data, it is stored in the non-volatile memory and has the previous exposure time information as a header in the non-volatile memory. Even if images are collected from different relays 23 ', there is no problem in the consistency of the image and the subject.
[0089]
Now, in the case of using another thin X-ray detector 22C (not shown) in the state shown in the procedure 2 of FIG. 10, the thin X-ray detector 22A or 22B is simply removed from the repeater 23 and the vacant What is necessary is just to set the thin X-ray detector 22C to a connection part. In this state, there are three thin X-ray detectors 22 that can be used as shown in FIG. Further, during the state of FIG. 9D, a new fourth thin X-ray detector 22D is connected to the repeater 23 in the valid state of all the thin X-ray detectors 22A, 22B, and 22C. In this case, the thin X-ray detector 22 removed from the repeater 23 for the longest time managed by the effective period counter 106 is deleted from the effective X-ray detector display area 114 of the system controller 31 and deleted. The thin X-ray detector 22D newly registered in the portion is displayed.
[0090]
At that time, the communication key is updated for the new thin X-ray detector 22D. The display in the effective X-ray detector display area 114 is changed as shown in FIGS. 9D to 9E. In the example of (d) → (e), the thin X-ray detector 22 (cassette / half cut / □ 160 μm) corresponding to the second icon from the top of (d) has been detached from the repeater 23 for the longest time. In (e), a new icon is registered in that portion. As can be seen from the above example, in FIG. 10, there are two mountable holder portions for the repeater 23, but it is possible to handle more than two thin X-ray detectors 22 at the same time.
[0091]
Further, in the state of FIG. 9E, three thin X-ray detectors 22 of the same type are in a controllable state, but the thin X-ray detectors corresponding to the respective icons 121 using the technology of the present invention. It is possible to control only the thin X-ray detector 22 which is assigned an individual communication key for each 22 and is selected in the operating state.
[0092]
【The invention's effect】
As described above, the X-ray imaging apparatus and the communication method thereof according to the present invention include a plurality of two-dimensional radiation detection means and communication control means capable of wireless communication, and the detection means and the communication control means are easily physical. The communication control means assigns individual ID keys to a plurality of detection means at the time of connection, and performs wireless communication based on the individual ID keys to perform X-ray imaging without malfunction. Can do.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an X-ray imaging system.
FIG. 2 is an equivalent circuit diagram of a first light detection unit.
FIG. 3 is a configuration diagram of a photodetector array.
FIG. 4 is a timing chart of photodetector array driving.
FIG. 5 is a timing chart of the X-ray imaging system according to the first embodiment.
FIG. 6 is a block circuit configuration diagram of an image processor.
FIG. 7 is a block circuit configuration diagram of a thin X-ray detector and a repeater.
FIG. 8 is an explanatory diagram of a display screen of an operator interface.
FIG. 9 is an explanatory diagram of an effective X-ray detector display area.
FIG. 10 is an explanatory diagram of a communication key assignment procedure.
FIG. 11 is a flowchart of a communication key assignment procedure.
FIG. 12 is an explanatory diagram of a communication key.
[Explanation of symbols]
1 X-ray room
2 X-ray control room
3 diagnosis and operation room
11 X-ray generator
15 Shooting bed
16 X-ray detector
17 grid
18 Scintillator
19 Photodetector array
21 Driver
22 Thin X-ray detector
23 Repeater
31 System controller
33 Monitor
34 Imaging controller
35 Image processor
51 Photodetector
52 Switching TFT
111 Display screen
114 Effective X-ray detector display area

Claims (6)

When the X-ray detector for acquiring the X-ray image is detected to approach the predetermined range, the X-ray detector specific information is acquired, and the X-ray detector specific information is acquired when the X-ray detector specific information is acquired. Communication control means for assigning an individual ID key necessary for wireless communication with the line detector;
An X-ray imaging apparatus comprising: an imaging control unit configured to wirelessly control the X-ray detector from which the unique information has been acquired by the communication control unit using the individual ID key. Communication control means for acquiring unique information of the X-ray detector by detecting that an X-ray detector for acquiring an X-ray image is close to a predetermined range;
Imaging control means for wirelessly controlling the X-ray detector from which the unique information has been acquired by the communication control means, using an individual ID key necessary for wireless communication,
The communication control means includes an ID assigning means for assigning the individual ID key necessary for wireless communication with the X-ray detector when acquiring the unique information of the X-ray detector;
An X-ray imaging apparatus comprising: an effective period counter that counts an effective period corresponding to the individual ID key allocated by the ID assigning unit.   The X-ray imaging apparatus according to claim 1, wherein the individual ID key reflects an ID of the communication control unit.   The X-ray imaging apparatus according to claim 2, wherein the X-ray detector has an ID as unique information.   The individual ID key for wireless communication between the X-ray detector and the communication control unit is determined by wireless connection between the X-ray detector and the communication control unit. Item 5. The X-ray imaging apparatus according to any one of Items 2 to 4. The communication control means acquires the unique information of the X-ray detector by detecting that the X-ray detector that acquires the X-ray image is close to a predetermined range, and obtains the unique information of the X-ray detector. Assigning an individual ID key necessary for wireless communication with the X-ray detector upon acquisition;
And a step of wirelessly controlling the X-ray detector from which the unique information has been acquired in the step by using the individual ID key.

Images