X-ray imaging device and control method thereof

Abstract

Provided are an X-ray imaging device and a control method thereof. The X-ray imaging device according to one embodiment of the present invention comprises: an X-ray generator including an X-ray source which emits X-rays; an X-ray detector which detects the X-rays emitted from the X-ray generator and generates a plurality of pieces of projection data; and a processor which generates a tomographic image on the basis of the plurality of pieces of projection data generated by the X-ray detector, wherein the X-ray generator can be moved so that the X-ray source is parallel to the X-ray detector, and the processor controls the X-ray generator so that the X-rays are emitted so that the central axis thereof is perpendicular to the X-ray detector while moving the X-ray source parallel to the X-ray detector along a preset path.

Description

X-ray imaging device and its control method

[0001] The present invention relates to an X-ray photographing device and an X-ray photographing image processing method, and more particularly, to an X-ray photographing device and an X-ray image processing method capable of miniaturizing an X-ray photographing device while minimizing distortion of a tomographic image.

[0002] When an X-ray imaging system captures a 2D X-ray image, the 2D X-ray image is an image in which X-rays are projected in one direction toward the X-ray imaging target. Therefore, when X-rays are projected toward the target in one direction, a problem occurs in which the image of the target overlaps and is obscured.

[0003] Meanwhile, to solve these problems, a representative device for irradiating patients with X-rays and taking pictures of an object is a computed tomography (CT) device. Among medical image processing devices, a computed tomography (CT) device, which is a tomography device, can provide cross-sectional images of an object, and has the advantage of being able to express the internal structure of an object (e.g., organs such as kidneys and lungs) without overlapping compared to a general X-ray device, so it is widely used for the precise diagnosis of diseases.

[0004] Recently, a tomosynthesis (DTS) X-ray imaging system that creates 3D images with low radiation compared to computed tomography (CT) devices has been introduced.

[0005] The tomosynthesis system is a technique that can obtain three-dimensional images with a low dose compared to computed tomography (CT), and can provide depth-specific tomographic images to eliminate overlapping or occlusion effects.

[0006] A tomosynthesis system typically rotates an analog X-ray generator in an arch shape around a rotational axis, and an X-ray detector moves or rotates according to the position of the X-ray generator while capturing multiple X-ray images, and then reconstructs the image into a three-dimensional image using a reconstruction algorithm.

[0007] A typical DTS (Digital Tomosynthesis) system captures and reconstructs multiple projection images to produce a three-dimensional image. Each projection image is designed to irradiate the entire area of ​​interest with X-rays, requiring a large distance between the detector and the generator.

[0008] When an X-ray enters the detector at an angle, an error in the detection position occurs due to the detector structure, and the image quality deteriorates beyond a certain angle. In addition, since the X-ray properties have a specific distribution for the X-ray irradiation field, the X-ray irradiation area / angle is limited to capture the image in order to use a uniform area in the center. For this reason, since the X-ray irradiation field has a limited size, the distance between the detector and the generator inevitably increases as the area of ​​interest to be captured becomes wider.

[0009] Therefore, the tomosynthesis X-ray imaging system has the disadvantages of being large in overall size and requiring a large space for installation because it acquires images by rotating an analog X-ray generator installed on a rail on the ceiling.

[0010] Therefore, there is a need for an X-ray imaging system that minimizes the space occupied by the X-ray imaging system, ensures convenience of installation, and is capable of being moved.

[0011] The problem to be solved by the present invention is to provide an X-ray photographing device and an X-ray image processing method that can minimize distortion of a tomographic image while miniaturizing the X-ray photographing device.

[0012] An X-ray photographing device according to an embodiment of the present invention includes an X-ray generator including an X-ray source that irradiates X-rays, an X-ray detector that detects X-rays irradiated from the X-ray generator to generate a plurality of projection data, and a processor that generates a tomographic image based on the plurality of projection data generated through the X-ray detector, wherein the X-ray generator is formed such that the X-ray source can move parallel to the X-ray detector, and the processor controls the X-ray generator such that a central axis of the X-ray is irradiated perpendicularly to the X-ray detector while moving the X-ray source parallel to the X-ray detector along a preset path.

[0013] In an embodiment, the X-ray generator is characterized in that the X-ray source is formed to be movable parallel to the X-ray detector within a region where the X-ray source does not leave the X-ray detector.

[0014] In an embodiment, the X-ray generator is characterized in that it is formed so that the edge of the X-ray irradiated from the X-ray source moves within a range that does not escape the X-ray detector.

[0015] In an embodiment, the processor is characterized in that the X-ray source irradiates X-rays at a first location and then moves to a second location different from the first location and then irradiates X-rays.

[0016] In an embodiment, the range of X-rays irradiated at the first location and the range of X-rays irradiated at the second location are characterized in that a portion overlaps.

[0017] In an embodiment, the processor is characterized in that it continuously irradiates the X-rays while moving the X-ray source.

[0018] In an embodiment, the apparatus further includes a sensing unit configured to sense the shape of an object to be photographed, and the processor is characterized in that it determines the preset path along which the X-ray source is to be positioned based on the boundary of the object to be photographed.

[0019] In an embodiment, the processor is characterized in that it controls the X-ray generator so that the X-ray source is positioned at the edge of the photographing object to irradiate X-rays, and controls the X-ray generator so that the X-ray source irradiates X-rays at predetermined intervals a preset number of times within the edge of the photographing object.

[0020] In the embodiment, the preset number of times and the predetermined interval are characterized in that they are variable according to user settings.

[0021] In an embodiment, the processor is characterized in that it irradiates X-rays while moving the X-ray source so that the entire range of the X-ray detector is imaged.

[0022] In an embodiment, the processor is characterized in that, when a part of the X-ray detector is set to be photographed, it controls the X-ray generator so that X-rays are irradiated only to the part of the X-ray detector.

[0023] According to the present invention, the generator moves along a 2D line (X-axis, Y-axis direction) in a horizontal direction with the detector, vertically irradiates X-rays to the detector to obtain projection data, and reconstructs the projection data to create a tomographic image, so that a high-quality, realistic 3D tomographic image can be obtained without distortion of both the center and the outer part of the object.

[0024] Further scope of the applicability of the present invention will become apparent from the detailed description below. However, since various modifications and variations within the spirit and scope of the present invention will become apparent to those skilled in the art, it should be understood that the detailed description and specific examples, such as preferred embodiments of the present invention, are given by way of example only.

[0025] Figure 1 is a drawing for explaining a conventional tomosynthesis system.

[0026] Figures 2 and 3 are conceptual diagrams to explain that image distortion becomes more severe when an X-ray imaging device is miniaturized.

[0027] FIG. 4 is a block diagram illustrating an X-ray photographing device according to an embodiment of the present invention.

[0028] FIG. 5 and FIG. 6 are conceptual diagrams for explaining an X-ray generator according to one embodiment of the present invention.

[0029] FIG. 7 is a conceptual diagram for explaining a state in which X-rays are irradiated when X-rays are generated by an X-ray generator according to an embodiment of the present invention.

[0030] Figure 8 is a conceptual diagram for explaining an X-ray irradiation method of an X-ray generator according to one embodiment of the present invention.

[0031] Figures 9 and 10 are conceptual diagrams for explaining various X-ray irradiation methods of the present invention.

[0032] Figure 11 is a conceptual diagram for explaining a conventional X-ray irradiation method and an X-ray irradiation method of the present invention.

[0033] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components will be given the same reference numbers, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably only for the convenience of writing the specification, and do not in themselves have distinct meanings or roles. In addition, when describing the embodiments disclosed in this specification, if it is determined that a specific description of a related known technology may obscure the gist of the embodiments disclosed in this specification, a detailed description thereof will be omitted. In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

[0034] Terms that include ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by these terms. These terms are used solely to distinguish one component from another.

[0035] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0036] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0037] In this application, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0038] The X-ray photographing device (100) of the present invention provides an X-ray photographing device (or Digital Tomosynthesis, DTS) capable of obtaining an image without distortion even when the distance between the X-ray generator (210) and the detector (230) is made short for miniaturization, and a method for controlling the same.

[0039] In the conventional DTS system, the X-ray beam (X-ray) from the generator passes through the object to be photographed and irradiates the entire area of ​​the detector.

[0040] Also, when the detector, the object to be photographed, and the generator are positioned in the same straight line, the X-ray beams from the detector and the generator are irradiated vertically. However, when the generator moves along a set orbit, the X-ray beam and the detector are irradiated obliquely, not vertically. Therefore, if the distance between the generator and the detector is shortened to miniaturize the system, the angle of the obliquely entering beam becomes larger, resulting in a deterioration in image quality.

[0041] The present invention increases the amount of X-ray beam irradiated vertically to the detector (230) by performing a 2D line scan on the generator over the detector (the plane for 2D scanning is scanned while moving parallel to the detector) and irradiates the area of ​​the detector in block units, thereby maintaining constant image quality without image distortion and enabling system miniaturization.

[0042] Figure 1 is a drawing for explaining a conventional tomosynthesis system.

[0043] In a conventional tomosynthesis system (10), an X-ray generator (101) rotates about 20 to 50 degrees around a predetermined rotation axis while irradiating an X-ray to a photographing target (102). An X-ray detector (103) can generate an electrical signal corresponding to the dose of the X-ray transmitted.

[0044] Meanwhile, when the X-ray generator (101) rotates and irradiates the photographing target (102) with X-rays, the projected X-rays are detected by the X-ray detector (103), and a plurality of projection data (106, 107, 108) can be generated.

[0045] Meanwhile, based on the first plane (Plane 1) and the second plane (Plane 2) of the photographing target (102), each of the first point (104) and the second point (105) can be projected by the X-ray emitted by the X-ray generator (101) and mapped to each of the plurality of projection data (106, 107, 108).

[0046] In this case, the first point (104) and the second point (105) mapped to each of the plurality of projection data (106, 107, 108) may be mapped differently due to the change in the angle of incidence caused by the rotational movement of the X-ray generator (101). Therefore, an additional step of reconstructing a 2D or 3D X-ray tomographic image of the photographing target (102) based on the plurality of projection data (106, 107, 108) is required.

[0047] Figures 2 and 3 are conceptual diagrams to explain that image distortion becomes more severe when an X-ray imaging device is miniaturized.

[0048] Referring to (a) of Fig. 2, when the distance between the X-ray generator and the X-ray detector is far, even if the X-ray generator moves from A to B to C and photographs the object, the distance of the projection data (Projection A, B, C) photographed by projecting each plane does not deviate significantly from the object.

[0049] However, referring to (b) of Fig. 2, as the distance between the X-ray generator and the X-ray detector gets closer, when the X-ray generator moves from A to B to C and photographs the object, the distance of the projection data (Projection A, B, C) photographed by projecting each plane deviates significantly from the object.

[0050] That is, when the system is miniaturized using the conventional tomosynthesis method, image distortion occurs, and specifically, the image of Projection B compared to Projection A and Projection C is severely distorted left and right based on the central axis of the X-ray beam.

[0051] Referring to (a) of FIG. 3, the X-ray generator (210) may include, for example, an X-ray source (211) and a collimator (a frame that restricts X-rays) (212). As illustrated in (a) of FIG. 3, X-rays irradiated from the X-ray source (211) may irradiate an object (270) so that projection data (400) may be generated in the X-ray detector (230).

[0052] Meanwhile, as shown in (a) of FIG. 3, if the distance between the X-ray generator (210) and the X-ray detector (230) (or the photographing target (270)) is the first distance (far), the size of the portion (400a) corresponding to the distorted image may have the first size (or, the angle at which the X-ray is incident from the edge of the photographing target to the X-ray detector (230) may have the first angle (α).

[0053] On the other hand, as shown in (b) of FIG. 3, if the SDD (Source Detector Distance) is a second distance shorter than the first distance due to miniaturization of the system, that is, if the distance between the X-ray source (211) and the X-ray detector (230) is shortened (i.e., the size of the portion (410a) corresponding to the distorted image may have a second size larger than the first size (or, the angle at which the X-ray is incident from the edge of the object to be photographed to the X-ray detector (230) may have a second angle (β) larger than the first angle).

[0054] That is, in the past, as the distance between the generator and the detector (the subject of the photograph) became closer, image distortion occurred, so the system was large because the distance between the generator and the detector was farther away.

[0055] However, the present invention provides a method for minimizing image distortion while minimizing the system (i.e., by making the distance between the X-ray generator (210) and the X-ray detector (230) closer), as shown in (b) of FIG. 3.

[0056] For example, the X-ray photographing device (100) of the present invention can be miniaturized so that the distance between the X-ray generator (210) and the X-ray detector (230) is 90 cm or less, and can provide a method for minimizing distortion while minimizing the distance between the X-ray generator and the X-ray detector so that the distance is 45 cm or less when photographing hands and feet, and 70 cm or less when photographing the chest.

[0057] FIG. 4 is a block diagram for explaining an X-ray photographing device according to an embodiment of the present invention, and FIGS. 5 and 6 are conceptual diagrams for explaining an X-ray generator according to an embodiment of the present invention.

[0058] An X-ray imaging device (100) may include an X-ray generator (210), an X-ray detector (230), a memory (250), and a processor (870).

[0059] The X-ray generator (210) may include an X-ray source. The X-ray source may be formed to be movable along a plane parallel to the X-ray detector (230), as illustrated in FIG. 5.

[0060] For example, the X-ray generator (210) may be formed with a first frame (213) corresponding to the X-axis and a second frame (214) corresponding to the Y-axis, and may include a first axis (215) formed to slide along the first frame and a second axis (216) formed to slide along the second frame.

[0061] The X-ray source (211) can be positioned at the intersection of the first axis (215) and the second axis (216).

[0062] Although not shown, the first frame (213) and the second frame (214) may be provided with an actuator (or motor) that moves the first axis (215) or the second axis (216), and the actuator may be driven under the control of the processor (870).

[0063] The processor (870) controls the actuators provided in the first frame (213) and the second frame (214) to position the X-ray source (211) at a desired position or at desired coordinates, thereby positioning the X-ray source (211) at a desired position through movement of the first and second axes (215, 216).

[0064] Accordingly, as illustrated in FIG. 6, the X-ray source is formed to be movable along a plane parallel to the X-ray detector (230), and can irradiate X-rays perpendicularly to the detector at a position designated by the control of the processor (870).

[0065] The X-ray detector (230) can generate an electrical signal corresponding to the dose of the X-rays transmitted. The X-ray detector (230) can generate projection data by generating the electrical signal.

[0066] The memory (250) stores programs for each signal processing and control within the processor (270), and can store signal-processed images, voices, or data signals, etc. The memory (250) can store a plurality of projection data.

[0067] The processor (870) can control the movement of the X-ray generator (210) or the X-ray detector (230), or control the on or off of the X-ray off when the X-ray source of the X-ray generator (210) is positioned at a desired position.

[0068] Additionally, the processor (870) can store a plurality of projection data generated from the X-ray detector (230) in the memory (250).

[0069] Additionally, the processor (870) can reconstruct a plurality of projection data into a 2D or 3D X-ray image, which is a cross-sectional image of the photographing target. For example, the processor (870) can apply a predetermined reconstruction algorithm based on a plurality of projection data to generate a 2D or 3D X-ray cross-sectional image.

[0070] Meanwhile, a representative reconstruction algorithm is FBP (filtered back projection). However, when the FBP (filtered back projection) reconstruction algorithm used in the conventional tomosynthesis system (10) disclosed in FIG. 1 is used in the X-ray photographing device (100), a problem of artifacts occurring in the reconstructed X-ray image may occur. In the conventional tomosynthesis system (10), the X-ray generator rotates around a predetermined rotation axis to obtain projection data, but the X-ray photographing device (20) moves horizontally to obtain projection data. Therefore, since the X-rays are incident at a limited angle on a part of the X-ray detector, only a part of the projection data is used to calculate one pixel value, and thus, discontinuous linear image artifacts may appear in the reconstructed X-ray image.

[0071] The X-ray generator (210) includes an X-ray source (211) that irradiates X-rays.

[0072] Additionally, the X-ray generator (210) may be formed to be movable parallel to the X-ray detector, as illustrated in FIGS. 5 and 6.

[0073] The X-ray detector (230) can detect X-rays irradiated from the X-ray generator (210) and generate a plurality of projection data.

[0074] The processor (870) can generate a tomographic image based on a plurality of projection data generated through the X-ray detector (230).

[0075] Additionally, the processor (870) can control the X-ray generator (210) to irradiate X-rays while moving the X-ray source parallel to the X-ray detector (230) along a preset path.

[0076] Specifically, the processor (870) can control the X-ray generator (210) to move the X-ray source parallel to the X-ray detector (230) along a preset path while irradiating the central axis of the X-ray perpendicular to the X-ray detector (230).

[0077] As the X-ray generator (210) moves parallel to the X-ray detector (230), and the central axis of the X-ray is irradiated perpendicularly to the X-ray detector (230), the range where each X-ray is irradiated can be photographed so that at least a part overlaps rather than being the same part.

[0078] Here, the preset path may be a path for moving the X-ray generator (210) so that the X-rays are irradiated without gaps to the X-ray detector (230), the photographing target (270), or the preset range, and may be determined or varied by user settings.

[0079] FIG. 7 is a conceptual diagram for explaining a state in which X-rays are irradiated when X-rays are generated by an X-ray generator according to an embodiment of the present invention.

[0080] The X-ray photographing device (100) of the present invention irradiates X-rays in the X-axis and Y-axis 2D directions while maintaining the X-ray generator (210) parallel to the X-ray detector (230). As illustrated in FIG. 7, the X-ray photographing device (100) can be formed so that when irradiating X-rays while moving the X-ray generator (210), a plurality of areas where X-rays are irradiated can scan the entire detector.

[0081] The X-ray generator (210) can be formed so that the X-ray source can move parallel to the X-ray detector within a region where the X-ray source does not leave the X-ray detector.

[0082] In addition, the X-ray generator (210) can be formed so that the edge of the X-ray irradiated from the X-ray source moves within a range that does not escape the X-ray detector (230), as shown on the right side of FIG. 7.

[0083] Specifically, as illustrated in FIG. 7, when an X-ray source irradiates an X-ray at a first position, an X-ray is irradiated vertically to a first point (800) corresponding to the first position by an X-ray detector (230), and a predetermined area (800a) centered on the first point (800) can be irradiated with the X-ray.

[0084] In addition, the processor (870) can irradiate X-rays after moving the X-ray source to a second position different from the first position. In this case, X-rays can be irradiated vertically to a second point (810) corresponding to the second position by the X-ray detector (230), and X-rays can be irradiated to a predetermined area (810b) centered on the second point (810).

[0085] At this time, since the X-ray must be irradiated so that the predetermined area (i.e., the edge of the X-ray) does not go beyond the X-ray detector (230), the range (820) in which the X-ray generator (210) moves may be smaller than the size of the X-ray detector (230), as shown on the right side of FIG. 7.

[0086] Figure 8 is a conceptual diagram for explaining an X-ray irradiation method of an X-ray generator according to one embodiment of the present invention.

[0087] Referring to (a) of FIG. 8, the processor (870) can irradiate X-rays after the X-ray source irradiates X-rays at a first location and then moves to a second location different from the first location.

[0088] At this time, the range of X-rays irradiated at the first location and the range of X-rays irradiated at the second location can be irradiated so that a portion overlaps.

[0089] Specifically, the processor (870) can irradiate X-rays while performing a two-dimensional scan along the X-axis and Y-axis of a two-dimensional plane parallel to the X-ray detector for an object to be photographed with an X-ray source. At this time, the X-ray generator (211) can move to a designated location or at a predetermined interval and irradiate X-rays at the designated location. At this time, the X-rays can be irradiated in the form of pulses.

[0090] The processor (870) can generate a tomographic image using a plurality of projection data acquired through a plurality of X-ray irradiations in this way.

[0091] As another example, as illustrated in (b) of FIG. 8, the processor (870) may continuously irradiate X-rays while moving the X-ray source.

[0092] Specifically, the processor (870) can irradiate X-rays while performing a two-dimensional scan along the X-axis and Y-axis of a two-dimensional plane parallel to the X-ray detector for an object to be photographed with an X-ray source. At this time, the X-ray source (211) moves to a designated position or at a certain interval and irradiates X-rays while moving. At this time, the X-rays can be irradiated continuously.

[0093] The processor (870) can generate a tomographic image using a plurality of projection data acquired through continuous X-ray irradiation.

[0094] Figures 9 and 10 are conceptual diagrams for explaining various X-ray irradiation methods of the present invention.

[0095] Referring to (a) of FIG. 9, the processor (870) can irradiate X-rays while moving the X-ray source so that the entire range of the X-ray detector (230) is captured.

[0096] Meanwhile, as illustrated in (b) of FIG. 9, the processor (870) may control the X-ray generator (210) so that X-rays are irradiated only to the partial area when a partial area of ​​the X-ray detector is set to be photographed.

[0097] At this time, the processor (870) can move the X-ray generator (210) parallel to the X-ray detector (230) so that the central axis of the X-ray vertically irradiated from the X-ray generator (210) to the X-ray detector (230) does not go beyond the boundary of the above-mentioned partial area (1000).

[0098] The number of times (or density) or interval at which the X-ray source is irradiated to image the above-mentioned area can be determined or changed by the user.

[0099] The above number of times and intervals can be set to a number of times and intervals that can capture all of the above-mentioned areas so that no part of the above-mentioned areas is missed for capture.

[0100] Meanwhile, referring to FIG. 10, the X-ray photographing device of the present invention may further include a sensing unit formed to sense the shape of an object to be photographed.

[0101] The above sensing unit may be a separate sensor such as a camera, an infrared camera, an ultrasonic sensor, a radar sensor, or an X-ray generator itself that determines the shape of an object through X-rays.

[0102] Referring to FIG. 10, the processor (870) can determine a preset path along which the X-ray source is to be positioned based on the border (1100) of the photographing object (270).

[0103] For example, the processor (870) may determine a preset path so that the X-ray source is positioned on the edge of the photographing object based on the edge of the photographing object sensed through the sensing unit.

[0104] Thereafter, the processor (870) can determine the preset path so that X-rays are irradiated to an area within the photographing object, so that X-rays are irradiated within the photographing object.

[0105] At this time, the number of times (or density) of X-rays irradiated or the predetermined interval at which X-rays are irradiated while moving the X-ray source over the photographing target can be determined or changed by the user setting.

[0106] Specifically, the processor (870) can control the X-ray generator so that the X-ray source is positioned at the edge of the photographing object to irradiate X-rays, and can control the X-ray generator so that the X-ray source irradiates X-rays at predetermined intervals a preset number of times within the edge of the photographing object.

[0107] The above preset number of times and the predetermined interval can be varied by user settings.

[0108] The above predetermined interval can be set within a range such that different ranges to which X-rays are irradiated overlap at least partially, and may have the same interval or different intervals. For example, if the radius of the range to which X-rays are irradiated is N (cm), the predetermined interval can have a value between 0 and N (cm).

[0109] The above-mentioned preset number of times and predetermined intervals can be set to an interval that allows the entire subject to be photographed without missing any portion of the subject to be photographed.

[0110] Figure 11 is a conceptual diagram for explaining a conventional X-ray irradiation method and an X-ray irradiation method of the present invention.

[0111] Referring to (a) of Fig. 11, conventionally, multiple images are acquired while an X-ray source moves, but at this time, the X-ray beam irradiates the entire detector or photographing area at any position of the X-ray source.

[0112] Additionally, the 1D and 2D movement of the X-ray source refers to the source's movement path, and the imaging area only acquires images of the entire detector range. Therefore, the disadvantage of image distortion due to miniaturization described above occurs.

[0113] Meanwhile, referring to (b) of FIG. 11, unlike conventional X-ray detectors, the present invention is a 2D area X-ray irradiation in which multiple X-rays are irradiated vertically to a detector area or a photographing area, and X-ray irradiation is performed multiple times on a part of an area from the detector or photographing object perspective. Therefore, even if the distance between the X-ray source and the X-ray detector is close, multiple vertical X-ray irradiations (1200a, 1200b,…, 1200n) are performed, so that distortion can be minimized.

[0114] According to the present invention, the generator moves along a 2D line (X-axis, Y-axis direction) in a horizontal direction with the detector, vertically irradiates X-rays to the detector to obtain projection data, and reconstructs the projection data to create a tomographic image, so that a high-quality, realistic 3D tomographic image can be obtained without distortion of both the center and the outer part of the object.

[0115] The present invention uses a single X-ray source and uses a method of moving the single X-ray source parallel to the X-ray detector while irradiating it perpendicularly to the X-ray detector, so it has the following advantages over conventional techniques using multiple X-ray sources.

[0116] First, various scan configurations and scanning methods can be provided as needed. The overall scan area can be changed based on the size of the object being photographed, while the step size and number of shots of the X-ray source can be flexibly adjusted to meet the required image quality.

[0117] Accordingly, the movement interval can be reduced and the number of shots increased when high-quality images are required, and the overall scan area can be reduced when the area of ​​interest is small.

[0118] On the other hand, when using a multi-array tube with multiple X-ray sources, the spacing in the direction of the tube array is fixed, and the degree of freedom is limited when reducing the scan area.

[0119] Second, when using a multi-array tube with multiple X-ray sources, there are differences in uniformity characteristics for each tube (Differences in dose reduction depending on X-ray dose, Focal Spot Size, and frequency of use).

[0120] When using a multi-array tube that uses multiple X-ray sources, there is a deviation in the characteristics of each tube, so even if it is operated with the same tube voltage and tube current, the X-ray dose is different. Therefore, the current must be finely adjusted for each tube to uniformly compensate for the dose.

[0121] Additionally, because there is variation in the focal spot size characteristics of each tube, pre-selection of the tubes is necessary and important.

[0122] In addition, when using a multi-array tube that uses multiple X-ray sources, there is a problem that maintenance is required to monitor the dose for each tube and correct the dose for each tube after using the product for a certain period of time, because the degree of deterioration for each tube is different even when the same number of shots are taken.

[0123] However, in the case of the present invention using a single X-ray source, this problem does not occur.

[0124] Third, when using a multi-array tube that uses multiple X-ray sources, differences in X-ray characteristic distribution occur even when driven with the same voltage and current, so image correction for each tube is required.

[0125] However, when moving using a single tube (single X-ray source) as in the present invention, there is no need for an X-ray performance calibration process and image correction between tubes.

[0126] Fourth, because X-ray irradiation requires high-voltage operation (tens of kV), interference between tubes occurs when multiple tubes are arrayed, which limits system design (e.g., adjusting the spacing between tubes). Furthermore, design miniaturization is limited.

[0127] On the other hand, the present invention is advantageous in miniaturization and weight reduction by reducing the size and weight of the generator by driving it with a single tube (single X-ray source) instead of an array tube.

[0128] In addition, the present invention operates with a single tube (single X-ray source) as opposed to an array tube, thereby reducing the price of important components and reducing the number of key components, thereby lowering the quality defect rate of the product, thereby increasing product competitiveness.

[0129] The present invention described above can be implemented as computer-readable code on a medium in which a program is recorded. Computer-readable media include all types of recording devices that store data that can be read by a computer system. Examples of computer-readable media include hard disk drives (HDDs), solid state disks (SSDs), silicon disk drives (SDDs), ROMs, RAMs, CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, etc., and also include media implemented in the form of carrier waves (e.g., transmission via the Internet). In addition, the computer may include a control unit (180) of a terminal. Therefore, the above detailed description should not be construed as limiting in all respects, but should be considered as illustrative. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are intended to be included in the scope of the present invention.

Claims

1. An X-ray generator including an X-ray source for irradiating X-rays; An X-ray detector that detects X-rays irradiated from the above X-ray generator and generates a plurality of projection data; and A processor for generating a tomographic image based on a plurality of projection data generated through the X-ray detector, The above X-ray generator is formed so that the X-ray source can move parallel to the X-ray detector, The above processor, An X-ray photographing device that controls an X-ray generator so that the central axis of the X-ray is irradiated perpendicularly to the X-ray detector while moving the X-ray source parallel to the X-ray detector along a preset path.

2. In paragraph 1, The above X-ray generator, An X-ray photographing device characterized in that the X-ray source is formed to be moveable parallel to the X-ray detector within a region that does not leave the X-ray detector.

3. In paragraph 2, The above X-ray generator, An X-ray photographing device characterized in that the edge of the X-ray irradiated from the X-ray source is formed to move within a range that does not leave the X-ray detector.

4. In paragraph 1, The above processor, An X-ray photographing device characterized in that the X-ray source irradiates X-rays at a first location and then moves to a second location different from the first location and then irradiates X-rays.

5. In paragraph 4, An X-ray photographing device, characterized in that the range of X-rays irradiated at the first location and the range of X-rays irradiated at the second location partially overlap.

6. In paragraph 1, The above processor, An X-ray photographing device characterized in that it continuously irradiates X-rays while moving the X-ray source.

7. In paragraph 1, It further includes a sensing unit formed to sense the shape of the photographing target, The above processor, An X-ray photographing device characterized in that the preset path along which the X-ray source is to be positioned is determined based on the boundary of the photographing target.

8. In paragraph 7, The above processor, The X-ray generator is controlled so that the X-ray source is positioned at the edge of the photographing target and X-rays are irradiated, An X-ray photographing device characterized in that the X-ray generator is controlled to irradiate X-rays at predetermined intervals a preset number of times within the boundary of the photographing target.

9. In paragraph 8, An X-ray imaging device, characterized in that the above-mentioned preset number of times and predetermined intervals are variable according to user settings.

10. In paragraph 1, The above processor, An X-ray photographing device characterized in that it irradiates X-rays while moving the X-ray source so that the entire range of the X-ray detector is photographed.

11. In paragraph 1, The above processor, An X-ray photographing device characterized in that when a certain area of ​​the X-ray detector is set to be photographed, the X-ray generator is controlled so that X-rays are irradiated only to the certain area.

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