JP2011056170A - Radiographic system and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiographic system and a method of controlling the same, capturing an image with high sharpness in a state where micro-vibration is constantly occurring in an X-ray source. <P>SOLUTION: This radiographic system includes: an X-ray source 11 for exposing a subject P to X-rays; and an X-ray detector 12 for detecting the X-rays transmitted through the subject P. The X-ray source 11 is provided with a vibration sensor 17 for detecting the vibration of the X-ray source 11. The vibration sensor 17 detects vibration amplitude A<SB>X</SB>, A<SB>Y</SB>concerning the XY directions of an image receiving part of the X-ray detector 12, and transmits the same to a PC13. A photographing control part 13a in the PC 13 obtains a synthesis amount ¾A¾ of the vibration amplitude A<SB>X</SB>, A<SB>Y</SB>, decides the binning number corresponding to the synthesis amount ¾A¾, and performs reading (binning read) of an image from the X-ray detector 12 based on the decided binning number after the end of exposure from the X-ray source 11. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an X-ray imaging system for imaging a subject with X-rays and a control method therefor.

  In the medical field or the like, an X-ray imaging system is widely used in which X-rays are irradiated (irradiated) from an X-ray source to an object, and X-rays transmitted through the object are imaged by an X-ray detector. At the time of imaging with X-rays, the X-ray source is preferably completely stationary with respect to the X-ray detector. However, in reality, it is difficult to completely suppress the vibration of the X-ray source with respect to the X-ray detector, and the positional relationship between the X-ray source and the X-ray detector fluctuates during imaging due to the vibration of the X-ray source. Due to this variation, there is a problem that the captured image is blurred and the sharpness is lowered.

  Therefore, in Patent Document 1, when an X-ray source or an X-ray detector is provided with a vibration sensor, and the vibration sensor detects a vibration amount that exceeds a specified value, X-ray exposure by the X-ray source is prohibited. It is disclosed.

JP 2003-245269 A

  However, in the X-ray imaging system described in Patent Document 1, the specified value is set to be higher than the vibration amount of the fine vibration in a situation in which the slight vibration is constantly generated between the X-ray source and the X-ray detector. In such a case, there is a problem in that the X-ray exposure prohibition state continues and imaging cannot be executed indefinitely. On the other hand, when the specified value is set lower than the vibration amount of the fine vibration, the sharpness of the photographed image is inevitably lowered due to the fine vibration.

  By the way, in recent years, portable X-ray imaging systems have been used in applications such as home medical care. In the portable X-ray imaging system, the X-ray source is small and lightweight, and is used by being suspended vertically above the examination site of the subject by, for example, an assembly-type holder. Usually, such a holder for an X-ray source is not stable and does not have a vibration-proof structure, and therefore the X-ray source is likely to vibrate. Furthermore, since a portable X-ray source has a small X-ray output and requires a long exposure time, there is a concern about image blur due to vibration. Therefore, the portable X-ray imaging system is required to solve the above problem.

  The present invention has been made in view of the above problems, and an X-ray imaging system capable of capturing an image with high sharpness and a control method thereof in a situation where slight vibrations are constantly generated in the X-ray source. The purpose is to provide.

  In order to achieve the above object, an X-ray imaging system of the present invention includes an X-ray source that exposes X-rays to a subject, an X-ray detector that detects X-rays transmitted through the subject, and the X-ray detector A vibration detecting means for detecting a vibration amount of the radiation source; a binning number is determined based on the vibration amount detected by the vibration detecting means; and after the exposure by the X-ray source is completed, the binning number is determined based on the determined binning number. Imaging control means for reading out an image from the X-ray detector.

  The imaging control means preferably determines the X-ray exposure time by the X-ray source according to the binning number determined based on the vibration amount.

  Further, an exposure instruction input means for inputting an instruction to start exposure by the X-ray source is provided, and the imaging control means issues an exposure instruction by the exposure instruction means when the vibration amount is larger than a reference value. It is preferable not to start the exposure as invalid.

  Further, the imaging control means stops the exposure by the X-ray source and reads the image from the X-ray detector when the vibration amount becomes larger than a reference value during the exposure by the X-ray source. It is preferable to carry out.

  Further, it is preferable that the imaging control unit restarts the exposure by the X-ray source when the vibration amount becomes equal to or less than the reference value within a predetermined time after the exposure is stopped.

  In addition, the image processing unit includes an image processing unit that combines an image read from the X-ray detector when the exposure is stopped and an image read from the X-ray detector after the exposure is resumed into one image. It is preferable.

  In addition, an imaging part input unit for inputting an imaging part is provided, and the imaging control unit is configured to provide a binning number and exposure to a vibration amount detected by the vibration detection unit in accordance with the imaging part input by the imaging part input unit. It is preferable to change the relationship of the firing time.

  The amount of vibration is preferably the amplitude of vibration of the X-ray source.

  The X-ray source and the X-ray detector are preferably portable.

  Furthermore, the control method of the X-ray imaging system of the present invention includes an X-ray source that exposes X-rays to a subject, an X-ray detector that detects X-rays transmitted through the subject, In a control method of an X-ray imaging system including a vibration detection unit that detects a vibration amount, a binning number is determined based on the vibration amount detected by the vibration detection unit, and after the exposure by the X-ray source is completed, An image is read out from the X-ray detector based on the determined binning number.

  In the present invention, the number of binning is determined based on the amount of vibration of the X-ray source, and after the exposure by the X-ray source is completed, the image is read from the X-ray detector based on the determined number of binning. An image with high sharpness can be taken under a situation in which slight vibration is constantly generated in the X-ray source.

1 is a schematic perspective view of an X-ray imaging system according to a first embodiment of the present invention. 1 is a schematic side view showing a configuration of an X-ray imaging system. It is a figure which shows the structure of a X-ray detector typically. It is a figure which shows the table which prescribes | regulates the relationship between the number of binning with respect to a vibration amplitude, and exposure time, (A) is a figure which shows the table used when an imaging | photography site | part is a chest, and (B) is a case where an imaging | photography site | part is a leg part. It is. It is a flowchart which shows the effect | action of an X-ray imaging system. It is a figure which shows a charge image, a read image, and an X-ray image typically. It is a flowchart which shows the effect | action of the X-ray imaging system which concerns on 2nd Embodiment of this invention.

(First embodiment)
In FIG. 1, an X-ray imaging system 10 according to the first embodiment of the present invention includes an X-ray tube (not shown) and a high voltage generator (not shown) that applies a tube voltage to the X-ray tube. An X-ray source 11 that generates a ray, an X-ray detector 12 that detects X-rays emitted from the X-ray source 11 and transmitted through a patient (subject) P, and the X-ray source 11 and the X-ray detector 12 It comprises a notebook personal computer (PC) 13 for performing operation control and image processing. The X-ray source 11, the X-ray detector 12, and the PC 13 are all portable, and can be carried to the home of a patient who undergoes home diagnosis, the site of an emergency patient, and the like, and X-ray imaging can be performed on the site.

  The X-ray source 11 is used while being held by an assembly-type holder 14. The holding tool 14 is configured by two sets of support legs 14b which are erected on the floor and whose upper ends are connected by a connector 14a, and a horizontal bar 14c which is connected between the two connectors 14a. A hook member 14d for suspending the X-ray source 11 is provided at the center of the horizontal bar 14c. The X-ray source 11 is attached with a grip portion 11a for carrying. The X-ray source 11 is held in a suspended state by hooking the grip portion 11a on the hook member 14d.

  The X-ray source 11 emits (irradiates) X-rays vertically downward while being held by the holder 14. The X-ray source 11 is provided with a collimator device (not shown), and X-rays generated by the X-ray tube are emitted by the collimator device with the irradiation field being restricted to a rectangular shape. The X-ray detector 12 is a flat panel detector (FPD) that generates image data by converting X-rays into electrical signals. The X-ray detector 12 is opposed to the X-ray source 11 via the patient P so that the X-ray emitted from the X-ray source 11 is received by the rectangular image receiving unit 12a. For example, the patient P is arranged such that the chest is located on the X-ray detector 12.

  The PC 13 is connected to the X-ray source 11 and the X-ray detector 12 via cables 15 and 16, respectively. As shown in FIG. 2, the image output from the X-ray detector 12 and the imaging control unit 13 a that causes the PC 13 to execute the exposure operation of the X-ray source 11 and the detection operation of the X-ray detector 12 in synchronization. An image processing unit 13b that performs image processing of data to generate image data for display is configured in cooperation with a CPU and a program stored in a memory (not shown). The PC 13 accepts input of imaging conditions (imaging site, etc.) through the operation unit 13c such as a keyboard, and controls the X-ray source 11 and the X-ray detector 12 based on the input values input through the operation unit 13c. Further, the PC 13 displays an X-ray image on the display unit 13d formed of a liquid crystal display device based on the image data generated by the image processing.

Further, a vibration sensor 17 is incorporated in the X-ray source 11. The vibration sensor 17 is a well-known acceleration sensor, and obtains the vibration amplitude of the X-ray source 11 in the XY direction by detecting the acceleration and the frequency in the XY direction of the image receiving unit 12a of the X-ray detector 12, respectively. The amplitude A is expressed as A = α / ω ² by the acceleration α and the frequency ω. The vibration sensor 17 obtains the vibration amplitude A _X in the X direction and the vibration amplitude A _Y in the Y direction based on this relational expression. The vibration sensor 17 sequentially measures the amplitudes A _X and A _Y and transmits them to the PC 13. As will be described in detail later, the imaging control unit 13a in the PC 13 controls the operations of the X-ray detector 12 and the X-ray source 11 based on the transmitted amplitudes A _X and A _Y.

  In FIG. 3, an X-ray detector 12 includes an image receiving unit 12a in which a plurality of detection elements 20 that convert X-rays into electric charges and are stored two-dimensionally along the XY direction on an active matrix substrate, and an image receiving unit 12a. Scanning control unit 21 for controlling the readout timing of charges from the signal, a signal conversion unit 22 for reading out charges accumulated in each detection element 20 of the image receiving unit 12a, converting them into image data, and storing them, and storing the image data in the PC 13 The image data transmitting unit 23 is configured to transmit to the image processing unit 13b. The image receiving unit 12a has, for example, a rectangular shape of about 43 cm × 43 cm, and the arrangement pitch of the detection elements 20 is about 200 μm in the XY directions.

  The scanning control unit 21 and each detection element 20 are connected by a scanning line 24 for each row of the detection elements 20, and the signal conversion unit 22 and each detection element 20 are signal lines 25 for each column of the detection elements 20. Connected by. The rows correspond to the X direction and the columns correspond to the Y direction.

As the detection element 20, X-rays are directly converted into charges corresponding to the incident dose by a conversion layer such as amorphous selenium (a-Se), and the converted charges are stored in a capacitor connected to an electrode below the conversion layer. Direct conversion type can be adopted. A TFT switch (not shown) is connected to each detection element 20, the gate electrode of the TFT switch is connected to the scanning line 24, the source electrode is connected to the capacitor, and the drain electrode is connected to the signal line 25. When the TFT switch is turned on by the drive pulse from the scanning control unit 21, the charge accumulated in the capacitor is output to the signal line 25. In addition, as a detection element 20, X-rays are once converted into visible light by a phosphor (scintillator) such as gadolinium oxide (Gd ₂ O ₃ ) or cesium iodide (CsI), and the converted visible light is charged by a photodiode. It is also possible to adopt an indirect conversion type that converts to and accumulates.

  The scanning control unit 21 includes a shift register, and sequentially supplies driving pulses to the scanning lines 24 based on control from the imaging control unit 13a. When performing binning, which will be described later, the scanning control unit 21 receives the number of binnings supplied from the imaging control unit 13a (“2 (rows) × 2 (columns)”, “3 (rows) × 3 (columns). ) Etc.), the drive pulse is supplied simultaneously to a plurality of adjacent scanning lines 24. For example, when the binning number is “2 × 2”, the scanning lines 24 are driven two rows at a time, and charges are simultaneously output from the two detection elements 20 to one signal line 25. Each charge output to the same signal line 25 is added (column addition) on the signal line 25.

  The signal conversion unit 22 includes a row addition circuit 22a, an integration amplifier circuit 22b, an A / D converter 22c, and an image memory 22d. The row addition circuit 22a adds the charges of a plurality of adjacent signal lines 25 in units of the number of columns of the binning numbers supplied from the imaging control unit 13a, and inputs the added charges to the integration amplifier circuit 22b. . For example, when the number of binning is “2 × 2”, the charge of the signal line 25 is added by two columns (row addition). When the binning is not performed, the row addition circuit 22a individually inputs the charges of the signal lines 25 to the integration amplifier circuit 22b without adding them.

  The integrating amplifier circuit 22b integrates the electric charge input from the row adding circuit 22a, converts it into a voltage signal (image signal), and inputs it to the A / D converter 22c. The A / D converter 22c converts the input image signal into digital image data and inputs it to the image memory 22d. The image memory 22d stores image data for a maximum of one frame (for the total number of detection elements 20).

  As described above, at the time of binning, a plurality of electric charges generated by each detection element 20 in the square area of “2 × 2” or “3 × 3” are obtained by the cooperation of the scanning control unit 21 and the row addition circuit 22a. It is added as a unit. This binning process reduces the resolution of the image data stored in the image memory 22d because the number of pixels is substantially reduced. However, the signal amount of each pixel increases, so that the S / N ratio is improved and the image data Sharpness is improved. In the present embodiment, the number of binning is the same in the row and column directions, and a binning process that is symmetric in the row and column directions is performed.

  Further, when binning is performed, the image processing unit 13b of the PC 13 performs interpolation processing such as spline interpolation on the image data transmitted from the image memory 22d (image data whose resolution has been reduced by binning). Then, image data equal to the resolution when binning is not performed is generated, and this image data is displayed on the display unit 13d as an X-ray image.

In the memory in the PC 13, as shown in FIGS. 4A and 4B, the combined amount | A | of the vibration amplitudes A _X and A _Y of the X-ray source 11 detected by the vibration sensor 17 and the number of binning And tables T1 and T2 that associate the relationship with the exposure time. One of the tables T1 and T2 is selected when the X-ray source 11 and the X-ray detector 12 are controlled by the imaging control unit 13a. Note that the combined amount | A | is an amount expressed by the following equation (1), and the imaging control unit 13a sequentially calculates the combined amount | A | from the vibration amplitudes A _X and A _Y. Hereinafter, the combined amount | A | of the vibration amplitudes A _X and A _Y is simply referred to as the vibration amplitude | A |.

| A | = ((A _X ) ² + (B _X ) ² )) ^1/2 (1)

The table T1 is selected when the imaging region is the chest. When the vibration amplitude | A | is 0 to 0.1 mm, the binning number is “1 × 1 (no binning)” and the vibration amplitude | A When | is 0.1 to 0.3 mm, the binning number is “2 × 2”, and when vibration amplitude | A | is 0.3 to 0.5 mm, the binning number is “3 × 3”. Is uniformly set to 500 msec regardless of the vibration amplitude | A |. As will be described later, when the vibration amplitude | A | is larger than 0.5 mm (reference amplitude A ₀ described later), the number of binning and the exposure time are not specified in order to prohibit exposure.

On the other hand, the table T2 is selected when the imaging part is a leg, and the binning number is “1 × 1 (no binning)” when the vibration amplitude | A | is 0 to 0.1 mm. When the irradiation time is 400 msec, the vibration amplitude | A | is 0.1 to 0.5 mm, the binning number is “2 × 2”, and the exposure time is 100 msec. Similarly, when the vibration amplitude | A | is larger than 0.5 mm (reference amplitude A ₀ described later), the number of binning and the exposure time are not specified in order to prohibit exposure.

  In both tables T1, T2, when the vibration amplitude | A | is 0 to 0.1 mm, the binning number is “1 × 1 (no binning)”. This is defined based on the fact that if the full width of vibration (twice the amplitude) is within the arrangement pitch, no blur due to vibration appears in the image. The upper limit of 0.1 mm corresponds to the arrangement pitch of the detection elements 20 being about 200 μm (= 0.2 mm).

  In the table T1, the exposure time is constant regardless of the number of binning. This is because in chest radiography, the main purpose is to diagnose organs such as the lungs, so it is necessary to emphasize the density of the image, and the purpose is to ensure a certain amount of X-ray exposure. .

  On the other hand, in the table T2, the exposure time is changed according to the number of binning. This is because in leg imaging, the main purpose is to diagnose bones, so it is necessary to emphasize image contrast (clearness of spatial shape), and exposure is increased as the number of binning increases. The aim is to further suppress blurring of the image due to vibration by shortening the shooting time. Specifically, in the table T2, the exposure time is set so as to be inversely proportional to the number of binnings (a number obtained by multiplying the number of binning rows and columns). Further, in the table T2, in order to emphasize the sharpness of the spatial shape, the number of binning exceeding “2 × 2” is not defined.

  Next, the operation of the X-ray imaging system 10 configured as described above will be described with reference to the flowchart shown in FIG. First, as shown in FIG. 1, as an imaging preparation, the engineer assembles the holder 14 and holds the X-ray source 11 on the holder 14 so as to face the X-ray source 11 through the imaging region of the patient P. The X-ray detector 12 is arranged, and the X-ray source 11 and the X-ray detector 12 are connected to the PC 13 via cables 15 and 16.

When preparation for imaging is completed and an engineer inputs an imaging region (chest or leg) from the operation unit 13c of the PC 13 (step S1: YES), the imaging control unit 13a stores the table T1, stored in the memory. The one corresponding to the imaging part input from T2 is selected (step S2). In step S2, a reference amplitude _A0 is set as a reference for prohibiting / stopping exposure when the vibration of the X-ray source 11 is large. The reference amplitude _{A 0} is set to 0.5mm even when any of the tables T1, T2 are selected. In step S2, the tube voltage and tube current of the X-ray source 11 are set to values corresponding to the imaging region. Then, after completing the various settings in step S2, the imaging control unit 13a causes the vibration sensor 17 to start detecting the vibration of the X-ray source 11 (step S3).

Next, when an instruction to start exposure is input from the operation unit 13c by the engineer (step S4: YES), the imaging control unit 13a is based on the amplitudes A _X and A _Y input from the vibration sensor 17 at that time. amplitude represents the amount of synthesized | is calculated, and the amplitude | | a a | is equal to or reference amplitude a ₀ is larger than (step S5). Amplitude | A | if is greater than the reference amplitude A ₀ (Step S5: YES), since the vibration is insufficient sharpening a binning process because it is too large, no good X-ray image is obtained,曝The instruction to start the irradiation is invalidated and the exposure is not started, and a “message prompting to input the exposure instruction again after reducing vibration” is displayed on the display unit 13d (step S6).

On the other hand, the amplitude | A | if the reference amplitude _{A 0} or less (step S5: NO), the imaging control unit 13a, the amplitude | A | binning number and exposure time corresponding to, selected in step S2 The setting is made based on the table (step S7), and the X-ray source 11 is started to expose X-rays (step S8). The vibration detection by the vibration sensor 17, even during irradiation is continuously performed, the imaging control unit 13a sequentially, the amplitude | A | is calculated and the amplitude | A | is determined whether reference amplitude A ₀ is greater than (Step S9).

During exposure the amplitude | A | are without exceeding the reference amplitude A ₀ (step S9: NO), the integration time from start of exposure (exposure integration time), reach the exposure time set in step S7 When it does (step S10: YES), the imaging control unit 13a ends the exposure by the X-ray source 11 (step S11). On the other hand, the amplitude during exposure | A | if exceeds the reference amplitude A ₀ (Step S9: YES), the photographing control unit 13a, a "message that they will be terminated exposure by increasing the oscillation" It is displayed on the display unit 13d (step S12), and the exposure is terminated (step S11).

  Upon completion of the exposure, the imaging control unit 13a controls the charge reading (binning reading) of the X-ray detector 12 based on the binning number set in step S7, and as a result, the image data stored in the image memory 22d. Is output to the PC 13 by the image data transmission unit 23 (step S13). Then, the image data input to the PC 13 is subjected to interpolation processing or the like by the image processing unit 13b and displayed on the display unit 13d as an X-ray image (step S14).

  In FIG. 6, an image I <b> 1 is a charge image accumulated in each detection element 20 of the X-ray detector 12 immediately after the exposure is finished in step S <b> 11, and blurring due to vibration of the X-ray source 11 occurs. It is shown that. The image I2 is a read image when “2 × 2” binning reading is performed in step S13, and shows that blurring is eliminated and the image is sharpened by binning. An image I3 is an X-ray image that is converted to the original resolution by the interpolation process and displayed on the display unit 13d.

(Second Embodiment)
In the first embodiment, when the amplitude | A | exceeds the reference amplitude A ₀ during the exposure after the start of the exposure, the exposure ends at that time and the image data is acquired from the X-ray detector 12. Reading and image display are performed on the display unit 13d. Therefore, the amplitude immediately after the start exposure | A | if exceeds the reference amplitude A _0, since exposure time is not sufficient, so that the blurred image of low luminance is displayed. Therefore, as the second embodiment, during exposure amplitude | showing a control method that allows the a clear image even if it exceeds the reference amplitude A ₀ obtained | A.

  FIG. 7 is a flowchart showing a control method of the X-ray imaging system in the second embodiment, and a portion surrounded by a broken line is different from that in the first embodiment. Since other parts are the same as those in the first embodiment, the same reference numerals as those in the first embodiment are given, and description thereof is omitted.

After X-ray source 11 in Step S8 starts the exposure, amplitude during exposure | A | if exceeds the reference amplitude _{A 0} (Step S9: YES), the photographing control unit 13a, the exposure The electric charge accumulated in the X-ray detector 12 at that time is read out (step S20), and as a result, the image data stored in the image memory 22d is output to the PC 13 (step S21). The image data input to the PC 13 is temporarily stored in the memory.

Next, it is determined whether or not the elapsed time after the exposure is temporarily stopped in step S20 is within a predetermined restart limit time (step S22), and if it is within the restart limit time (step S22: NO). , the amplitude | a | is equal to or reference amplitude _{a 0} is larger than (step S23). Amplitude | A | leave exceeds a reference amplitude _{A 0} (Step S23: YES), if the restart time limit has passed (step S22: YES), the photographing control unit 13a, "the exposure vibration caused “Stopped and the resumption limit time has passed without the vibration being stopped” is displayed on the display unit 13d (step S24). In this case, in step S21, the image data stored in the memory in the PC 13 is displayed on the display unit 13d as an X-ray image after interpolation processing or the like (step S14).

On the other hand, when the amplitude | A | becomes equal to or less than the reference amplitude A ₀ within the restart limit time (step S23: NO), the imaging control unit 13a causes the X-ray source 11 to resume X-ray exposure ( Step S25) and return to Step S9. Thereafter, again the amplitude | A | if exceeds the reference amplitude A ₀ is exposure is stopped (step S20), stored in the X-ray detector 12 during the period from exposure resume until exposure stop As a result, the image data stored in the image memory 22d is output and stored in the memory in the PC 13 (step S21).

  Thereafter, the imaging control unit 13a executes the same steps as described above. When exposure stop and exposure restart are performed, a plurality of image data are stored in the memory in the PC 13. In this case, the image processing unit 13b generates a single image data by aligning a plurality of image data so as to align the edges of the image and performing a synthesis process, and this image data is displayed as an X-ray image. 13d is displayed. Note that the above resumption time limit may be changed by an input from the operation unit 13c.

  In this way, a high-luminance and clear X-ray image is displayed by combining a plurality of image data obtained by interrupting and resuming exposure. Note that the above image composition may be performed by using the marker reflected in the image as a reference. This marker can be formed by arranging a shielding plate made of lead or the like formed in a predetermined shape (for example, a rectangular shape having a pixel size) on the X-ray incident side of the X-ray detector 12. In the case of the direct conversion type X-ray detector 12, a shielding plate may be disposed on the conversion layer. In the case of the indirect conversion type X-ray detector 12, the scintillator or between the scintillator and the photodiode is used. What is necessary is just to arrange | position a shielding board between them.

In the first and second embodiments, the vibration sensor 17 detects the vibration amplitudes A _X and A _Y in the X direction and the Y direction, and the combined amount of the vibration amplitudes A _X and A _Y | A | Based on the above, determination of the number of binning and exposure time and determination of prohibition / stop of exposure are performed, but vibration detection in two directions is not necessarily required, and only one direction may be used. In the configuration of the X-ray source 11 shown in FIG. 1, the X-ray source 11 is likely to swing in the Y direction. Direction vibration detection is preferably performed.

In the first and second embodiments, binning is performed symmetrically in the X direction and the Y direction. However, based on the vibration amplitudes A _X and A _Y detected by the vibration sensor 17, the X direction and Y It is also preferable to perform binning asymmetrically in the direction. For example, when A _X = 0.05 mm and A _Y = 0.2 mm, the binning number is set to “1 × 2”.

  In the first and second embodiments, the table for the chest and the leg is exemplified as the table defining the relationship between the number of binning and the exposure time with respect to the vibration amplitude. It goes without saying that a table for another imaging region such as the head may be used. The specified values in each table may be changed as appropriate.

  In the first and second embodiments, binning (so-called hardware binning) is performed by adding charges in the X-ray detector 12, but instead of this, digital processing is performed without binning. After the image data is generated, binning (so-called software binning) may be performed by image processing in the PC 13.

  In the first and second embodiments described above, when the vibration amplitude of the X-ray source 11 exceeds the reference value, a message is displayed on the display unit 13d to notify the technician that the exposure has been prohibited / stopped. Although the notification is made, this notification may be performed by sound output from the PC 13 or the X-ray source 11 or lighting of an LED provided in the PC 13 or the X-ray source 11.

  Further, in the first and second embodiments, the vibration sensor 17 is constituted by an acceleration sensor, but it is also possible to detect the vibration amplitude of the X-ray source 11 using an inclination sensor instead of the acceleration sensor. is there. In this case, the maximum tilt angle of the X-ray source 11 is detected by the tilt sensor, and the vibration amplitude can be obtained from the maximum tilt angle and the swing radius of the X-ray source 11. Further, a piezoelectric sensor or the like can be used as the vibration sensor 17.

DESCRIPTION OF SYMBOLS 10 X-ray imaging system 11 X-ray source 12 X-ray detector 12a Image receiving part 13a Imaging control part 13b Image processing part 13c Operation part 13d Display part 14 Holder 17 Vibration sensor 20 Detection element 21 Scan control part 22 Signal conversion part 22a line Adder circuit 24 Scan line 25 Signal line

Claims (10)

An X-ray source for exposing the subject to X-rays;
An X-ray detector for detecting X-rays transmitted through the subject;
Vibration detecting means for detecting a vibration amount of the X-ray source;
Imaging control means for determining the number of binning based on the amount of vibration detected by the vibration detecting means, and for reading out an image from the X-ray detector based on the determined number of binning after completion of exposure by the X-ray source When,
An X-ray imaging system comprising:   The X-ray imaging system according to claim 1, wherein the imaging control unit determines an X-ray exposure time by the X-ray source according to a binning number determined based on the vibration amount. An exposure instruction input means for inputting an instruction to start exposure by the X-ray source;
3. The X-ray imaging according to claim 1, wherein when the amount of vibration is larger than a reference value, the imaging control unit invalidates the exposure instruction by the exposure instruction unit and does not start the exposure. system.   The imaging control means stops the exposure by the X-ray source and reads the image from the X-ray detector when the vibration amount becomes larger than a reference value during the exposure by the X-ray source. The X-ray imaging system according to claim 1, wherein:   5. The exposure control according to claim 4, wherein the imaging control unit resumes the exposure by the X-ray source when the vibration amount becomes equal to or less than the reference value within a predetermined time after the exposure is stopped. X-ray imaging system.   Image processing means comprising combining an image read from the X-ray detector when the exposure is stopped and an image read from the X-ray detector after the exposure is resumed into one image. 6. The X-ray imaging system according to claim 5, wherein An imaging part input means for inputting an imaging part is provided,
The imaging control unit changes a relationship between a binning number and an exposure time with respect to a vibration amount detected by the vibration detection unit according to an imaging region input by the imaging region input unit. The X-ray imaging system according to 1.   The X-ray imaging system according to claim 1, wherein the vibration amount is an amplitude of vibration of the X-ray source.   The X-ray imaging system according to any one of 1 to 8, wherein the X-ray source and the X-ray detector are portable. An X-ray comprising an X-ray source that exposes the X-ray to the subject, an X-ray detector that detects the X-ray transmitted through the subject, and a vibration detection means that detects the amount of vibration of the X-ray source. In the control method of the photographing system,
A binning number is determined based on a vibration amount detected by the vibration detecting means, and after the exposure by the X-ray source is completed, an image is read from the X-ray detector based on the determined binning number. A control method of the X-ray imaging system.

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