JP4708559B2 - Radiation imaging system, imaging method, and storage medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to, for example, a radiation imaging system used in an apparatus or a system for acquiring a captured image by radiation imaging such as X-rays, Shoot The present invention relates to a shadow method and a storage medium.
[0002]
[Prior art]
Conventionally, for example, as an X-ray imaging system for medical diagnosis, there is a film screen system in which an intensifying screen and an X-ray photographic film are combined. Such a system converts X-rays transmitted through a subject, that is, X-rays containing internal information of the subject into visible light proportional to the intensity of the X-rays by an intensifying screen, and the X-ray photographic film is converted by the visible light. By exposing it to light, an X-ray image of the subject is formed on the X-ray photographic film.
[0003]
In recent years, digital X-ray imaging apparatuses that acquire an X-ray image of a subject as a digital image have become widespread, and it has become possible to acquire an X-ray image of a chest or the like used for medical diagnosis as a digital image. .
[0004]
As a digital X-ray imaging apparatus, for example, there is a portable imaging apparatus 800 in which only a sensor unit is portable as shown in FIG. Such an imaging apparatus 800 is generally called “cassette” or “electronic cassette”.
[0005]
[Problems to be solved by the invention]
However, the conventional photographing apparatus such as the electronic cassette 800 shown in FIG. 13 has the following problems.
That is, the electronic cassette 800 as shown in FIG. 13 is excellent in portability, but has a very narrow shooting range. For this reason, there are many cases where a desired imaging region does not fall within the imaging range. In such a case, it is necessary to perform imaging several times.
[0006]
Specifically, for example, there are various diagnostic methods using X-ray images. In the case of a method of comparing left-hand and right-hand X-ray images and making a diagnosis based on the difference, the electronic cassette 800 When performing imaging for acquiring X-ray images of the left hand and right hand, the left hand and the right hand often do not fit within the imaging range of the electronic cassette 800. Therefore, it is necessary to divide into two shootings, left hand shooting and right hand shooting. In addition to the time and effort required for radiography, this requires two exposures, that is, two X-ray exposures to the subject (subject). The burden on the human body will increase accordingly.
[0007]
Therefore, the present invention is made to eliminate the above-mentioned drawbacks, and by configuring a plurality of imaging parts to be capable of imaging at the same time, it is excellent in workability and can reduce the burden on the subject. Possible radiography system, Shoot It is an object of the present invention to provide a computer-readable storage medium storing a shadow method and a program for causing a computer to execute processing steps for implementing the method.
Further, the present invention is a radiation imaging system that is excellent in workability and can reduce the burden on the subject by being configured so that the imaging range can be widened, Shoot It is an object of the present invention to provide a computer-readable storage medium storing a shadow method and a program for causing a computer to execute processing steps for implementing the method.
[0008]
[Means for Solving the Problems]
Under such a purpose, the radiation imaging system of the present invention has a plurality of portable cassette-type imaging units that form a radiation image with an imaging device arranged two-dimensionally, Selection means for selecting at least one imaging unit to be used for one imaging among the plurality of imaging units, and when one of the plurality of imaging units is selected, imaging by the selected one imaging unit In response to receiving a signal indicating that the preparatory operation has been completed, the radiation generator is controlled to generate radiation, and when a plurality of the imaging units are selected, In response to instructions requiring exposure to radiation generators The Instructing multiple shooting units to perform shooting preparation operations, The Each of multiple shooting departments The Control means for controlling the radiation generator to generate radiation when a signal indicating that the imaging preparation operation has been completed is received from each of the plurality of imaging units, and the plurality of imaging units according to the control And a synthesizing unit that synthesizes a plurality of radiographic images formed by.
[0010]
An imaging method of the present invention is an imaging method of a radiographic system having a plurality of portable cassette-type imaging units that form a radiographic image with an imaging device arranged two-dimensionally, A selection step of selecting at least one imaging unit to be used for one imaging from among the plurality of imaging units, and when one of the plurality of imaging units is selected in the selection step, the selected one imaging Control for generating radiation to the radiation generator in response to receiving a signal indicating that the imaging preparation operation by the unit has been completed, and when a plurality of the imaging units are selected, In response to instructions requiring exposure to radiation generators The Instructing multiple shooting units to perform shooting preparation operations, The Each of multiple shooting departments The A control step for controlling the radiation generating device to generate radiation when a signal indicating that the imaging preparation operation is completed is received from each of the plurality of imaging units; and the plurality of imaging units according to the control And a combining step of combining a plurality of radiographic images formed by.
[0011]
The storage medium of the present invention is a computer-readable recording medium storing a program for controlling a radiation imaging system having a plurality of portable cassette-type imaging units that form radiation images with two-dimensionally arranged imaging elements. A storage medium, A selection step of selecting at least one imaging unit to be used for one imaging from among the plurality of imaging units, and when one of the plurality of imaging units is selected in the selection step, the selected one imaging Control for generating radiation to the radiation generator in response to receiving a signal indicating that the imaging preparation operation by the unit has been completed, and when a plurality of the imaging units are selected, In response to instructions requiring exposure to radiation generators The Instructing multiple shooting units to perform shooting preparation operations, The Each of multiple shooting departments The A control step for controlling the radiation generating device to generate radiation when a signal indicating that the imaging preparation operation is completed is received from each of the plurality of imaging units; and the plurality of imaging units according to the control A computer-readable storage medium storing a program for causing a computer to perform a combining step of combining a plurality of radiation images formed by the computer.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0023]
(First embodiment)
The present invention is applied to, for example, an X-ray imaging system 100 as shown in FIG.
[0024]
<Overall configuration of X-ray imaging system 100>
The X-ray imaging system 100 includes an X-ray generation unit 117, electronic cassettes 101 a and 101 b connected to the sensor connection unit 103, and a system control unit 106.
The X-ray generation unit 117 and the electronic cassettes 101 a and 101 b are installed in the X-ray room 104, and the system control unit 106 is installed in the X-ray control room 105.
[0025]
The X-ray generator 117 includes an X-ray tube 119 that generates an X-ray beam, a high-pressure generation source 118 that drives the X-ray tube 119, and an X-ray beam generated by the X-ray tube 119 in a desired imaging region. The X-ray aperture 120 is narrowed down.
[0026]
The system control unit 106 includes a host computer device and the like, and includes an imaging control unit 107, an image processing unit 108, a memory 109 including a hard disk and a RAM, an external storage device 110, a main control unit 111, and an interface 112 to which a monitor 115 is connected. The sensor switching unit 112 to which the user interface 114 is connected is connected to be communicable with each other via a bus 160.
[0027]
The main control unit 111 controls operation of the entire X-ray imaging system 100.
The memory 109 stores processing programs and data for operation control in the main control unit 111, image data obtained by photographing with the electronic cassettes 101a and 101b, and the like.
Therefore, the main control unit 111 controls the overall operation of the X-ray imaging system 100 by reading and executing a predetermined processing program from the memory 109.
[0028]
The sensor connection unit 103 is configured so that a plurality of electronic cassettes can be connected. Here, for simplicity of explanation, it is assumed that two electronic cassettes 101 a and 101 b are connected to the sensor connection unit 103 as an example.
[0029]
The imaging control unit 107 performs operation control of the electronic cassettes 101a and 101b via the sensor connection unit 103, as well as operation control of the high-voltage generation source 118 and the X-ray diaphragm 120 of the X-ray generation unit 117.
[0030]
The image processing unit 108 performs appropriate image processing such as offset correction and gain correction on the image data supplied from the electronic cassettes 101 a and 101 b via the sensor connection unit 103.
[0031]
The user interface 114 includes an operation unit such as a keyboard, and various operation instructions are input from the user 116.
Thereby, for example, the monitor 115 displays the image data in the memory 109 in accordance with an instruction from the user 116. Further, the image data in the memory 109 is stored in the hard disk 109 or the external storage device 110 in accordance with an instruction from the user 116.
[0032]
When the sensor switching unit 113 receives an operation instruction from the user 116 using the user interface 114, in particular, a switching instruction for the electronic cassettes 101 a and 101 b, the sensor switching unit 113 supplies the instruction information (sensor switching information) to the imaging control unit 107.
Therefore, when the imaging control unit 107 receives the sensor switching information from the sensor switching unit 113, the imaging control unit 107 switches the electronic cassette used for photographing among the electronic cassettes 101a and 101b based on the information.
[0033]
Although the electronic cassettes 101a and 101b will be described in detail later, each has the same configuration, and the power is supplied by the main control unit 111 of the system control unit 106.
Also, of the electronic cassettes 101a and 101b, control of which electronic cassette is to be turned on, that is, which electronic force cassette is used for photographing, or both electronic cassettes 101a and 101b are used simultaneously. The main control unit 111 controls whether or not to perform shooting based on an operation instruction from the user 116.
In addition, you may make it provide the structure which turns on an LED lamp at the time of selection so that selection electronic cassette can be confirmed with respect to electronic cassette 101a, 101b.
[0034]
<Configuration of Electronic Cassette 101a, 101b>
Each of the electronic cassettes 101a and 101b is equipped with a communication frame memory 150 for temporarily storing image data obtained by photographing.
In addition, each of the electronic cassettes 101a and 101b includes an imaging unit configured by a combination of a phosphor 201 and a sensor unit 202, as shown in FIG.
[0035]
The phosphor 201 converts X-rays incident on the electronic cassette 101a (X-rays transmitted through the subject) into a visible light image.
Although details will be described later, the sensor unit 202 is configured by two-dimensionally arranged photoelectric conversion elements, and amorphous silicon (amorphous silicon: a-Si film) is used as the photoelectric conversion layer, for example. This is because it is not only easy to form a photocarrier on a sensor substrate such as a large-area glass substrate, but also because it can be used as a semiconductor material for TFTs as switching elements. is there.
Therefore, visible light output from the phosphor 201 is absorbed by the sensor substrate of the sensor unit 202, where photocarriers are formed and accumulated.
[0036]
FIG. 3 specifically shows the internal configuration of the sensor unit 202.
The sensor unit 202 includes a photodetector array 401. The photodetector array 401 is composed of, for example, about 2000 × 2000 to 4000 × 4000 pixels. The array area of the photodetector array 401 is, for example, about 200 mm × 200 mm to 500 mm × 500 mm.
[0037]
Here, for simplicity of explanation, as an example, the photodetector array 401 is composed of 2048 × 2048 pixels, and the array area is 215 mm × 215 mm. Therefore, the size of one pixel is about 105 × 105 μm.
The photodetector array 401 has a two-dimensional configuration in which 2048 pixels arranged in the horizontal direction are set as one block, and the 2048 blocks are arranged in the vertical direction.
[0038]
FIG. 4 shows an example of the configuration of an equivalent circuit focusing on one pixel (photoelectric conversion element).
[0039]
The photoelectric conversion element includes a light detection unit 301 and a switching thin film transistor (hereinafter referred to as “switching TFT”) 303 for controlling charge accumulation and reading. For example, amorphous silicon (a− Si) is added.
[0040]
The light detection unit 301 includes a parallel circuit of a photodiode 301a and a capacitor 301b.
In FIG. 4 described above, the charge due to the photoelectric effect in the light detection unit 301 is represented as “constant current source 302”.
The capacitor 301b may be a parasitic capacitance of the photodiode 301a or an additional capacitor that improves the dynamic range of the photodiode 301a.
[0041]
The cathode of the photodiode 301a of the light detection unit 301 is connected to a bias power source 304 via a bias wiring Lb that is a common electrode (D electrode).
On the other hand, the anode of the photodiode 301 a of the light detection unit 301 is connected from the gate electrode (G electrode) to the capacitor 305 and the charge readout preamplifier 306 through the switching TFT 303.
An input to the preamplifier 306 is connected to the ground via a reset switch 308 and a signal line bias power source 309.
[0042]
In the one photoelectric conversion element shown in FIG. 4, first, the switching TFT 303 and the reset switch 309 are temporarily turned on, and the capacitor 301b is reset. Thereafter, the switching TFT 303 and the reset switch 309 are turned off.
When X-rays are exposed to the subject 170 from the X-ray generator 117, the transmitted X-rays of the subject 170 are converted into a visible light image by the phosphor 201 (see FIG. 2 above), and the photoelectric Incident to the conversion element.
[0043]
In the photoelectric conversion element, first, the photodiode 301a becomes conductive by the visible light image, and discharges the capacitor 301b.
Next, when the switching TFT 303 is turned on, the capacitor 301b and the capacitor 305 are connected. Thereby, the electric charge of the capacitor 301b is transmitted to the capacitor 305.
The voltage accumulated in the capacitor 305 is amplified by the preamplifier 306 or converted into a voltage by the capacitor 307 and output to the outside.
[0044]
Returning to FIG. 3, focusing on the entire photodetector array 401 in which the photoelectric conversion elements as shown in FIG. 4 are two-dimensionally arranged, the configuration of the entire sensor unit 202 will be described more specifically.
[0045]
As shown in FIG. 4, one photoelectric conversion element (pixel) includes one light detection unit 301 and a switching TFT 303.
In FIG. 3, the photoelectric conversion elements PD (1, 1) to (2048, 2048) correspond to the light detection unit 301, and the transfer switches SW (1, 1) to (2048, 2048) correspond to the switching TFT 303. .
[0046]
The gate electrode (G electrode) of the photoelectric conversion element PD (m, n) is connected to the common column signal line Lcm for the column via the corresponding transfer switch SW (m, n).
For example, the photoelectric conversion elements PD (1, 1) to (2048, 1) in the first column are connected to the first column signal line Lc1.
[0047]
All the common electrodes (D electrodes) of the respective photoelectric conversion elements PD (m, n) are connected to the bias power source 304 through the bias wiring Lb.
The control terminals of transfer switches SW (m, n) in the same row are connected to a common row selection line Lrn.
For example, the transfer switches SW (1, 1) to (1, 2048) in the first row are connected to the row selection line Lr1.
[0048]
Row selection lines Lr1 to 2048 are connected to timing control circuit 404 through gate drive circuit 403.
The gate driving circuit 403 decodes the control signal from the timing control circuit 404 and determines which line of the photoelectric conversion element signal charges should be read out, and 2048 pieces that are opened and closed according to the output of the address decoder 410. Switch element SW. With such a configuration, the signal charge of the photoelectric conversion element PD (m, n) connected to the switch SW (m, n) of an arbitrary line Lrn can be read out.
As the gate drive circuit 403, for example, a circuit constituted by a shift register used in a liquid crystal display or the like may be used.
[0049]
Column signal lines Lc1 to 2048 are connected to signal readout circuit 402 controlled by timing control circuit 404.
The signal readout circuit 402 includes preamplifiers 406-1 to 2048 that amplify signal potentials from the column signal lines Lc1 to 2048, and sample hold (S / H) circuits 407-1 to 407-1 that sample and hold the outputs of the preamplifiers 406-1 to 2048. 2048, an analog multiplexer 408 that multiplexes the outputs of the S / H circuits 407-1 to 2048 on the time axis, and an A / D converter 409 that digitizes the analog output of the analog multiplexer 408.
The output of the A / D converter 409 is input to the communication frame memory 150.
[0050]
In the sensor unit 202 as described above, first, the charge (photophotograph) accumulated in the photoelectric conversion element PD (m, n) according to the visible light from the phosphor 201, that is, according to the X-ray dose transmitted through the subject 170. The carrier) is controlled by the gate drive circuit 403, and the transfer switch SW (m, n) connected to the row selection line (gate line) Lrm of the gate drive circuit 403 is turned on, so that an image for one line is obtained. Read out as a signal.
[0051]
The read signal is amplified by the amplifier 406-n, sampled and held by the sample hold circuit 407-n, and then input to the analog multiplexer 408.
Switching control by the analog multiplexer 408 is performed by the timing control circuit 404.
The output of the analog multiplexer 408 is converted into digital data by the A / D converter 409.
[0052]
The digital data is transferred to the system control unit 106 through the communication memory (frame memory) 150 and the sensor connection unit 103 (see FIG. 1) sequentially under the control of the timing control circuit 404.
Therefore, the system control unit 106 can obtain two-dimensional image data of the entire sensor unit 202 (the entire electronic cassette).
[0053]
<Operation of X-ray Imaging System 100>
FIG. 5 shows the operation timing from the X-ray imaging of the subject 170 to the acquisition of the X-ray image of the subject 170 in the X-ray imaging system 100 of FIG.
[0054]
Here, in the following description, for simplicity of explanation, the electronic cassette 101a is “cassette A”, the electronic cassette 101b is “cassette B”, and these two cassettes A and B are simultaneously driven to perform X-rays. Let's take a picture. This instruction, that is, an instruction to perform photographing using the two cassettes A and B simultaneously, is input by the user 116 through the user interface 114 and supplied to the imaging control unit 107 and the like via the sensor switching unit 103. Become.
[0055]
In FIG. 5, “501” indicates an imaging request signal (exposure request SW signal) by the user interface 114.
“502” indicates a ready signal (imaging request instruction signal) of the X-ray generator 117.
“503” indicates an actual X-ray exposure state.
“504” indicates an imaging request signal (X-ray imaging request signal) from the imaging controller 107 to the cassettes A and B based on an instruction from the user 116.
“505” indicates imaging ready signals (X-ray detector ready signals) of the cassettes A and B.
“506” indicates a power control signal in the cassettes A and B.
“507” and “509” indicate data transfer request signals for the cassettes A and B, respectively.
“508” and “510” indicate the timing of image transfer and image processing of the force settings A and B, respectively.
[0056]
Therefore, first, the cassettes A and B stand by in a state where the power control signal is 0FF as indicated by “506” until a detector preparation request or a photographing request is issued from the user 116.
Specifically, in the configuration shown in FIG. 3, the row selection line Lr, the column signal line Lc, and the bias wiring Lb are held at the same potential (particularly, the signal GND level) by a switch (not shown). No bias is applied to the detector array 401.
Note that the potential of the row selection line Lr, the column signal line Lc, and the bias wiring Lb is kept at the GND potential by cutting off the signal readout circuit 402, the gate driving circuit 403, and the bias power supply 404 or the power supply including the bias power supply 404. May be.
[0057]
Next, when the exposure request SW1 of the user interface 114 is operated by the user 116 (see “1st SW” of “501”), the imaging controller 107 changes the X-ray generator 117 to the imaging ready state and the cassette A , B is issued a control instruction to shift to the shooting preparation state.
Receiving this, the force sets A and B apply a bias to the photodetector array 401, and, for example, when a predetermined time (several seconds or more) is required for preparation for photographing, perform the operation for the preparation. Start.
[0058]
Next, when the exposure request SW2 of the user interface 114 is operated by the user 116 (see 2ndSW of “501”), the imaging control unit 107 synchronizes the cassettes A and B with the X-ray generator 117. Controls the shooting operation.
Specifically, for example, the imaging control unit 107 sends an imaging request signal to the cassettes A and B at the timing of the X-ray imaging request signal indicated by “504” in accordance with an instruction (imaging request instruction) by the operation of the exposure request SW2. Is asserted.
[0059]
The cassettes A and B return an X-ray detector ready signal (see “505”) to the imaging controller 107 when preparation for imaging is completed.
The imaging controller 107 requests X-ray exposure (X-ray generation request) from the X-ray generator 117 based on the transition of the X-ray detector ready signals from the two cassettes A and B (“X-ray generation request”). 503 ").
The X-ray generator 117 generates X-rays while an X-ray generation request is made from the imaging controller 107 (while an X-ray generation request signal is supplied).
[0060]
When the imaging controller 107 recognizes that the X-ray generator 117 has generated a predetermined X-ray dose, the imaging controller 107 negates an X-ray generation request signal (see “503”) for the X-ray generator 117 and By negating the X-ray imaging request signal (see “504”), the image acquisition timing is notified to the force sets A and B.
[0061]
Based on the image acquisition timing from the imaging controller 107, the force sets A and B start the operation of the signal readout circuit 402 (see FIG. 3 above) that has been in a standby state until this time.
After a predetermined wait time for establishing the signal readout circuit 402, image data is read out from the X-ray detector array 401 under the control of the timing control circuit 404, and an X-ray image is acquired.
[0062]
The above-described image acquisition operation is simultaneously executed by the two cassettes A and B by one exposure of X-rays.
Therefore, X-ray images are temporarily stored in the communication frame memories 150 of the cassettes A and B, respectively.
Each of the communication frame memories 150 of the cassettes A and B has a capacity capable of storing at least one image data.
[0063]
The system control unit 106 first transmits a data transfer request signal (see “507”) to the first cassette (here, cassette A).
The cassette A that has received the data transfer request signal transmits the X-ray image data (A1) temporarily stored in the communication frame memory 150 to the system control unit 106 (see “508”).
[0064]
When the system control unit 106 recognizes that the data transfer from the cassette A has been completed, the system control unit 106 subsequently transmits a data transfer request signal (see “509”) to the other cassette B.
The cassette B that has received the data transfer request signal transmits the X-ray image data (B1) temporarily stored in the communication frame memory 150 to the system control unit 106 (see “510”).
[0065]
As described above, the X-ray image data (A1) obtained by the cassette A and the X-ray image data (B1) obtained by the cassette B are sequentially transferred to the system control unit 106.
[0066]
When the transfer of the X-ray image data of the two cassettes A and B to the system control unit 106 is completed, the imaging control unit 107 returns the cassettes A and B to the standby state again in order to obtain a correction image. Transition.
Thereafter, in the same manner as the acquisition of the X-ray image data (A1, B1) described above, the force settings A, B respectively acquire correction image (dark image) data at the same time.
[0067]
That is, the system control unit 106 first transmits a data transfer request signal (refer to “507”) to the first cassette (here, cassette A).
The cassette A that has received the data transfer request signal transmits the offset correction image data (A2) temporarily stored in the communication frame memory 150 to the system control unit 106 (see “508”).
[0068]
When the system control unit 106 recognizes that the data transfer from the cassette A has been completed, the system control unit 106 subsequently transmits a data transfer request signal (see “509”) to the other cassette B.
The cassette B that has received the data transfer request signal transmits the offset correction image data (B2) temporarily stored in the communication frame memory 150 to the system control unit 106 (see “510”).
[0069]
As described above, the offset correction image data (A2) obtained by the cassette A and the offset correction image data (B2) obtained by the cassette B are sequentially transferred to the system control unit 106.
[0070]
Note that the imaging sequence when acquiring the image data for offset correction may be slightly different with respect to the X-ray exposure time, etc., every time imaging is performed. By acquiring, a higher quality image can be obtained.
[0071]
In the system control unit 106, the image processing unit 108 performs offset correction using the offset correction image data (A2, B2) or gain correction image data for each of the X-ray image data (A1, B1). A basic correction process such as a gain correction using is performed (see “508” and “510”).
For example, the image processing unit 108 uses the X-ray image data (A1, B1) obtained by the two cassettes A, B as one image for each of the X-ray image data (A1, B1). Correction processing including offset correction processing and gain correction processing for matching the respective image characteristics is performed so that it can be handled as data.
[0072]
The offset correction process here uses the offset correction image data (A2, B2) read without performing X-ray exposure in order to correct the influence of dark current or the like included in the signal charge. It includes processing for correcting X-ray image data (A1, B1) at the time of radiation exposure.
The gain correction processing uses X-ray imaging at the time of X-ray exposure using gain correction image data obtained by directly irradiating cassettes A and B with only X-rays without passing through the subject 170. It includes a process of correcting gain variation for each pixel by correcting the image data (A1, B1). The gain correction image data is acquired in advance at the time of shipment from the factory or before each photographing.
[0073]
Then, after matching the image characteristics of the X-ray image data (A1, B1), the image processing unit 108 handles these X-ray image data (A1, B1) as one image data, Arbitrary various image processing such as gradation processing, DR (Dynamic Range) processing, and joint processing of two images is performed on the image data.
[0074]
Incidentally, when the image processing unit 108 handles two X-ray images as one image, the arrangement relationship between the two X-ray images is determined by the following configuration. .
[0075]
For example, as shown in FIG. 6, the cassette A is provided with arrangement detection units 601 to 604 for determining the arrangement status, and the cassette B similarly has an arrangement detection unit 605 for determining the arrangement status. 608 is provided.
The arrangement detection units (electrodes) 601 to 608 are configured such that, for example, by combining force sets A and B, any of the arrangement detection units comes into contact, and the positional relationship can be determined based on the contact state.
[0076]
The force sets A and B have a structure that comes into contact with each other when they are combined.
Moreover, when the cassettes A and B are combined, an attachment structure that does not shift the position may be used.
[0077]
Therefore, the image processing unit 108 performs the image processing as described above according to the arrangement relationship between the cassettes A and B indicated by the contact states of the arrangement detection units 601 to 608.
For example, when the cassettes A and B have an arrangement relationship as shown in FIG. 7A (the cassette A is on the left and the cassette B is on the right), the image processing unit 108 is 1 as shown in FIG. Image processing is performed so that a single image (X-ray image A obtained by the cassette A is left and X-ray image B obtained by the cassette B is right) is obtained.
Further, when the cassettes A and B have an arrangement relationship as shown in FIG. 7C (the cassette A is on the right and the cassette B is on the left), the image processing unit 108 is as shown in FIG. Image processing is performed so that one image (the X-ray image A obtained by the cassette A is right and the X-ray image B obtained by the cassette B is left) is obtained.
[0078]
One composite image obtained from one image obtained by the image processing unit 108 as described above, that is, two X-ray images obtained by photographing two cassettes A and B simultaneously. Is displayed on the monitor 115 or stored in the external storage device 110, for example.
[0079]
As described above, in the present embodiment, since the two electronic cassettes 101a and 101b are simultaneously driven to perform shooting at one time, the shooting that was conventionally divided into two times is completed in one time. Can do. For example, even in the case of making a diagnosis based on the captured images of the right hand and the left hand, the captured images of the right hand and the left hand can be obtained by a single shooting without the need to separately shoot the right hand and the left hand.
Therefore, the efficiency of the imaging work is improved, and the burden on the subject 170 is reduced because the subject 170 only needs to be exposed once.
[0080]
In the first embodiment, the image transfer of the cassette B (see “509” and “510”) shown in FIG. 5 may be configured as follows.
For example, as shown in FIG. 8, after receiving the offset correction image data (A2) from the cassette A, the system control unit 106 subsequently transmits a data transfer request signal to the cassette B (“509 ′”). "reference). The cassette B sequentially transfers the image data for offset correction (B2) together with the X-ray image data (B1) to the system control unit 106.
However, in this case, the communication memory 150 of the cassette B needs a capacity capable of storing at least two pieces of image data.
[0081]
Further, in the first embodiment, the two cassettes A and B are configured to be able to perform shooting by driving them simultaneously. However, the present invention is not limited to the two cassettes A and B, and is arbitrary. A plurality of cassettes may be simultaneously driven to perform photographing.
[0082]
(Second Embodiment)
The present invention is applied to, for example, an X-ray imaging system 700 as shown in FIG.
In the X-ray imaging system 700 of FIG. 9, the same reference numerals are given to the portions that operate in the same manner as the X-ray imaging system 100 of FIG. 1, and the detailed description thereof is omitted. Here, only the configuration different from that of the first embodiment will be specifically described.
[0083]
In the X-ray imaging system 700, each of the two electronic cassettes 101a and 101b includes a two-dimensionally arranged photoelectric conversion element as described with reference to FIGS.
[0084]
Specifically, the electronic cassettes 101a and 101b in the present embodiment will be described. First, FIGS. 10A and 10B show the structures of the electronic cassettes 101a and 101b.
As shown in FIG. 10A, for example, in the electronic cassette 101a, the light detection array 401 (see FIG. 3) is arranged in contact with any one side of the electronic force cassette 101a.
A gate driving circuit 403, a signal reading circuit 402, a timing control circuit 404, a communication frame memory 150, and the like are arranged in an empty space in the casing of the electronic force set 101a.
[0085]
The light detection array 401 is formed on a glass substrate. At the time of forming the light detection array 401, as shown in FIG. 11A, two electronic force sets 101a and 101b are in contact with the light detection array 401. When they are close to each other, cutting is performed so that the pixels exist up to the end face of the glass substrate so that the light detection arrays 401 of the respective electronic force sets 101a and 101b can be close to each other with a pixel pitch or less. And end face processing.
Details of FIG. 11B will be described later.
[0086]
In the electronic force sets 101 a and 101 b, the side where the light detection array 401 is in contact has a structure that cannot be contacted from the outside by a cover in order to protect the light detection array 401. Therefore, when the two electronic force sets 101a and 101b are combined, the cover can be removed and the two electronic force sets 101a and 101b can be combined as shown in FIG. It has a structure.
In addition, when combining the two electronic force sets 101a and 101b, it is good also as a structure which the said cover opens automatically.
[0087]
Further, as shown in FIG. 10B, for example, in the electronic force set 101a, an electrode 801 is provided on a connection side with another electronic cassette.
Therefore, in a state where the two electronic force sets 101a and 101b are combined, it can be determined whether or not the respective light detection arrays 401 are in accurate contact with each other depending on whether or not the electrode 801 is in contact. .
In addition, it is good also as an attachment structure where cassettes are fixed when two electronic force cassettes 101a and 101b are united.
[0088]
Regarding the operation of the X-ray imaging system 700 of the present embodiment including the electronic force sets 101a and 101b as described above, refer to the operation of the X-ray imaging system 100 of the first embodiment (see FIGS. 5 and 8 above). ), But the processing in the image processing unit 108 based on the arrangement relationship of the electronic force sets 101a and 101b is slightly different.
[0089]
That is, in the present embodiment, since the light detection arrays 401 of the two electronic force sets 101a and 101b are particularly close to or equal to the pixel pitch, the image processing portion 108 is the same as that shown in FIG. The arrangement relationship of the electronic cassettes 101a and 101b shown by the contact state of the electrode 801 shown in (b) is the arrangement relationship shown in FIG. 12 (a) (the cassette A is on the left and the cassette B is on the right. When the detection array 401 is connected), one image (X-ray image A obtained with the cassette A is left, X-ray obtained with the cassette B as shown in FIG. Image processing is performed so as to obtain an image in which the captured image B is connected to the right.
Further, when the cassettes A and B have an arrangement relationship as shown in FIG. 12C (an arrangement relationship in which the cassette A is on the right and the cassette B is on the left and the respective light detection arrays 401 are connected), The processing unit 108 is connected as a single image (X-ray image A obtained with the cassette A is on the right and the X-ray image B obtained with the cassette B is on the left as shown in FIG. Image processing is performed to obtain an image.
[0090]
In addition, the image processing unit 108 corrects the low frequency in terms of spatial frequency so that the density of the connection portion of two X-ray images is continuously changed as the correction processing described in the first embodiment. Processing including processing is performed.
[0091]
As described above, in this embodiment, the optical detection arrays 401 of the two electronic force sets 101a and 101b are brought close to the pixel pitch or less, and the two electronic cassettes 101a and 101b are driven at the same time. Since the photographing is configured, the photographing range can be widened. For this reason, it is possible to complete the photographing that has been divided into two times in the past. Therefore, the efficiency of the imaging work is improved, and the burden on the subject 170 is reduced because the subject 170 only needs to be exposed once.
[0092]
In the second embodiment, the light detection arrays 401 of the two electronic force sets 101a and 101b are arranged close to each other. However, the number of the electronic cassettes close to each other is not limited to two. As the number of electronic cassettes to be brought closer to each other is increased, the photographing range can be further expanded.
Specifically, for example, first, as shown in FIG. 3, the light detection array 401 has a matrix structure, and the signal readout circuit 402 and the gate drive circuit 403 must be connected to at least two sides thereof. Therefore, as shown in FIG. 11A, when the two electronic force sets 101a and 101b are brought close to each other, the remaining two sides to which the signal readout circuit 402 and the gate drive circuit 703 are not connected are used. Although they are close to each other, as shown in FIG. 11B, the four electronic cassettes 101a to 101d may be close to each other. When the two electronic force sets 101a and 101b are configured so as to be close to each other, processing such as end face processing of the light detection array 401 and attachment of a protective cover is performed as shown in FIG. On the other hand, when the four electronic force sets 101a to 101d are configured to be close to each other, the processing is executed for two sides.
[0093]
In the first and second embodiments, the power of the two electronic force sets 101a and 101b is supplied from the outside. However, the present invention is not limited to this. It is good also as a structure by which the battery is mounted with respect to 101a, 101b.
[0094]
In the first and second embodiments, the arrangement relationship between the two electronic force sets 101a and 101b is determined based on the contact points of the electrodes. However, the present invention is not limited to this. The determination may be made by a button switch or the like.
Further, the combination mechanism of the electronic force sets 101a and 101b is not limited to that shown in FIG. 7 or FIG.
[0095]
In the first and second embodiments, the electronic force sets 101a and 101b and the system control unit 106 are connected by a signal line or the like. However, the present invention is not limited to this. A portable memory is mounted on the sets 101a and 101b, and the memory in which the photographed image data is stored after photographing is connected to the system control unit 106, so that the system control unit 106 reads the photographed image data from the memory. You may make it comprise as follows. Alternatively, the captured image data may be propagated in the air from the electronic force sets 101a and 101b to the system control unit 106 by optical communication.
[0096]
Another object of the present invention is to supply a storage medium storing software program codes for realizing the functions of the host and terminal according to the first and second embodiments to the system or apparatus, and the computer of the system or apparatus. Needless to say, this can also be achieved by (or CPU or MPU) reading and executing the program code stored in the storage medium.
In this case, the program code itself read from the storage medium realizes the functions of the first and second embodiments, and the storage medium storing the program code constitutes the present invention.
A ROM, floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, or the like can be used as a storage medium for supplying the program code.
Further, by executing the program code read by the computer, not only the functions of the first and second embodiments are realized, but also an OS running on the computer based on the instruction of the program code. Needless to say, the present invention includes a case where the functions of the first and second embodiments are realized by performing part or all of the actual processing.
Further, after the program code read from the storage medium is written to the memory provided in the extension function board inserted in the computer or the function extension unit connected to the computer, the function extension is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the first and second embodiments are realized by the processing.
[0097]
【The invention's effect】
As described above, in the present invention, a plurality of photographing means (portable electronic cassettes, etc.) are photographed in parallel (driven substantially simultaneously, etc.), and a plurality of photographed images obtained thereby are processed. A composite image is acquired (processed as one image).
Thereby, for example, even when the imaging region of the subject does not fit within the imaging range of one imaging means, it is not necessary to perform imaging in several times, and the captured image of the imaging region can be obtained by one imaging. Obtainable. This is particularly effective in the case of radiography such as X-rays because the number of exposures to the subject can be reduced and the burden on the subject can be reduced. Specifically, for example, even when diagnosis is performed using X-ray images of the right hand and the left hand, it is not necessary to perform X-ray imaging of the right hand and the left hand separately, and the right hand and the left hand can be performed in one X-ray image. Each X-ray image can be obtained.
[0098]
In addition, when the imaging unit (such as a sensor unit in which photoelectric conversion elements are two-dimensionally arranged) of the imaging unit is configured to be close to the imaging unit of another imaging unit, the imaging range can be widened. For this reason, it becomes easy to fit the imaging region of the subject in the imaging range, and the imaging that has been divided into two in the past can be completed in one time. Particularly in the case of this configuration, in the case of radiography such as X-rays, the number of exposures to the subject can be reduced, and the burden on the subject can be reduced.
[0099]
Therefore, according to the present invention, it is possible to improve the shooting work efficiency and reduce the burden on the subject.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an X-ray imaging system to which the present invention is applied in a first embodiment.
FIG. 2 is a diagram for explaining a configuration of an electronic cassette of the X-ray imaging system.
FIG. 3 is a diagram for explaining a configuration of a sensor unit of the electronic cassette.
FIG. 4 is a diagram for explaining a configuration of a photoelectric conversion element of the sensor unit.
FIG. 5 is a diagram for explaining the operation of the X-ray imaging system.
FIG. 6 is a diagram for explaining a method of determining the arrangement state of the electronic cassette.
FIG. 7 is a diagram for explaining processing of an image obtained by the electronic cassette.
FIG. 8 is a diagram for explaining another operation of the X-ray imaging system.
FIG. 9 is a block diagram showing a configuration of an X-ray imaging system to which the present invention is applied in the second embodiment.
FIG. 10 is a diagram for explaining a configuration of an electronic cassette of the X-ray imaging system.
FIG. 11 is a diagram for explaining a configuration for bringing the electronic cassette close to each other.
FIG. 12 is a diagram for explaining processing of an image obtained by the electronic cassette.
FIG. 13 is a diagram for explaining a conventional electronic cassette.
[Explanation of symbols]
100 X-ray imaging system
101a, 101b Electronic cassette
103 Sensor connection
104 X-ray room
105 X-ray control room
106 System control unit
107 Imaging control unit
108 Image processing unit
109 memory
110 External storage device
111 Main control unit
112 interface
113 Sensor switching part
114 User interface
115 monitor
116 users
117 X-ray generator
118 High pressure source
119 X-ray tube
120 X-ray aperture
150 Frame memory for communication
160 bus

Claims (12)

It has multiple portable cassette-type imaging units that form radiation images with two-dimensionally arranged imaging elements,
Selecting means for selecting at least one imaging unit to be used for imaging among the plurality of imaging units;
When one of the plurality of imaging units is selected, the radiation generation apparatus generates radiation in response to reception of a signal indicating that the imaging preparation operation by the selected one imaging unit has been completed. Control
If a plurality of the imaging unit has been selected to instruct the execution of the photographic preparation operation to said plurality of imaging unit in response to instruction requesting exposure to said radiation generator, each of the plurality of imaging unit s and control means for controlling to generate the radiation to the radiation generator when receiving a signal indicating that the photographic preparation operation has been completed from each of the plurality of image pickup unit,
Combining means for combining a plurality of radiographic images formed by the plurality of imaging units according to the control;
A radiation imaging system comprising: The imaging unit has a detection unit on a side surface of the imaging unit for detecting whether the imaging unit is in contact with another imaging unit different from the imaging unit among the plurality of imaging units,
The combination means determines a connection position of a plurality of radiographic images formed by the plurality of imaging units according to the detection result when contact is detected by the detection unit. The radiation imaging system described in 1. The radiation imaging system according to claim 2 , wherein the imaging unit further includes an attachment / detachment mechanism that fixes the detection unit of the imaging unit and a detection unit of another imaging unit in contact with each other. The imaging unit includes a housing and a radiation detector disposed in the housing close to at least one side surface of the housing;
The radiation imaging system according to claim 2 , wherein the detection unit is provided on the side surface of the imaging unit. A cover that can be opened and closed is disposed on the side surface of the housing,
The radiation imaging system according to claim 4 , wherein the detection unit is exposed so as to be in contact with the other imaging unit when the cover is opened. The imaging unit includes a drive circuit that supplies a drive signal to the radiation detector;
A readout circuit for reading out an electrical signal generated by the radiation detector;
The imaging unit is disposed so that a space between at least one side surface of the housing and the radiation detector is smaller than a space between other side surfaces and the radiation detector,
The radiation imaging system according to claim 4 , wherein the drive circuit and the readout circuit are disposed between the radiation detector and another side surface different from the at least one side surface. A battery for driving the drive circuit and the readout circuit;
The radiation imaging system according to claim 6 , further comprising: a transmission unit that wirelessly transmits the radiation image data formed by the imaging unit. The radiation imaging system according to claim 1, characterized by further comprising display means for displaying the shadow shooting said selected.   Control sequentially outputting a plurality of radiographic images obtained by irradiating the plurality of imaging units with radiation, and sequentially outputting a plurality of dark images obtained without irradiating the plurality of imaging units with radiation. The radiographic system according to claim 1, further comprising a control unit that performs the control.   The imaging preparation operation of the imaging unit is an operation of causing the imaging device to shift to a state in which charges obtained by detecting radiation from the radiation generation apparatus can be accumulated. Radiography system. An imaging method of a radiation imaging system having a plurality of portable cassette-type imaging units that form a radiation image with an imaging device arranged two-dimensionally,
A selection step of selecting at least one imaging unit to be used for one imaging among the plurality of imaging units;
When one of the plurality of imaging units is selected in the selection step, the radiation generating apparatus is in response to receiving a signal indicating that the imaging preparation operation by the selected one imaging unit has been completed. Control to generate radiation,
If a plurality of the imaging unit has been selected to instruct the execution of the photographic preparation operation to said plurality of imaging unit in response to instruction requesting exposure to said radiation generator, each of the plurality of imaging unit s a control step of performing control for generating radiation to the radiation generator when receiving a signal indicating that the photographic preparation operation has been completed from each of the plurality of image pickup unit,
A combining step of combining a plurality of radiation images formed by the plurality of imaging units according to the control;
A photographing method characterized by comprising: A computer-readable storage medium storing a program for controlling a radiation imaging system having a plurality of portable cassette-type imaging units that form a radiation image with an imaging device arranged two-dimensionally,
A selection step of selecting at least one imaging unit to be used for one imaging among the plurality of imaging units;
When one of the plurality of imaging units is selected in the selection step, the radiation generating apparatus is in response to receiving a signal indicating that the imaging preparation operation by the selected one imaging unit has been completed. Control to generate radiation,
If a plurality of the imaging unit has been selected to instruct the execution of the photographic preparation operation to said plurality of imaging unit in response to instruction requesting exposure to said radiation generator, each of the plurality of imaging unit s a control step of performing control for generating radiation to the radiation generator when receiving a signal indicating that the photographic preparation operation has been completed from each of the plurality of image pickup unit,
A combining step of combining a plurality of radiation images formed by the plurality of imaging units according to the control;
A computer-readable storage medium storing a program for causing a computer to execute the program.

Images