X-ray imaging system and offset detection method and motion compensation method thereof

Abstract

The invention relates to an X-ray imaging system and an offset detection method and a motion compensation method thereof. The X-ray imaging system comprises a suspension device, a detection bed and a stand column, a detector is installed on the stand column, the detection bed is provided with a bed panel, the suspension device comprises an X-ray source, a distance measuring unit is installed on the suspension device, and the offset detection method comprises the steps that at least one piece of distance information is obtained, and at least one offset is obtained; the distance information comprises the distance between the distance measuring unit and at least one position of the bed panel and / or the distance between the distance measuring unit and at least one position of the detector, and the at least one offset comprises the offset of the stand column in the vertical direction and the offset of the suspension device in the horizontal direction and / or the vertical direction; and at least one of the offset of the detection bed in the horizontal direction and / or the vertical direction, the offset between the X-ray source and the center of the bed panel, the relative offset between the suspension device and the stand column, and the relative offset between the suspension device and the detection bed.

Description

Technical Field

[0001] The present invention relates to medical imaging technology, and more particularly to an X-ray imaging system and an offset detection method and a motion compensation method thereof. Background Art

[0002] In an X-ray imaging system, radiation from an X-ray source is directed toward a subject, which is typically a patient in medical diagnostic applications. A portion of the radiation passes through the subject and strikes a detector, which is divided into a matrix of discrete elements (e.g., pixels). The detector elements are read out to produce an output signal based on the amount or intensity of radiation striking each pixel area. The signal can then be processed to produce a medical image that can be displayed for inspection, which can be displayed in a display device of the X-ray imaging system.

[0003] Generally, when the suspension device of the X-ray imaging system moves relative to the inspection bed, the suspension device should be parallel to the upper surface of the inspection bed or the lifting direction of the inspection bed. Similarly, when the suspension device moves relative to the column, the movement direction of the suspension device should be parallel to the movement direction of the detector on the column. When the suspension device is not aligned or offset with the inspection bed, the image quality of the acquired medical image will be relatively poor. In this case, it is necessary to call on-site maintenance personnel for inspection to determine which component is offset and perform corresponding calibration. This maintenance process is not only complicated but also time-consuming. Summary of the invention

[0004] The invention provides an X-ray imaging system and an offset detection method and a motion compensation method thereof.

[0005] An exemplary embodiment of the present invention provides a method for detecting an offset of an X-ray imaging system. The X-ray imaging system includes a suspension device, a detection bed and a column, a detector is installed on the column, the detection bed has a bed panel, the suspension device includes an X-ray source, and a distance measuring unit is installed on the suspension device. The offset detection method includes acquiring at least one distance information based on the distance measuring unit, and acquiring at least one offset of the X-ray imaging system based on the at least one distance information, wherein the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and the detector at at least one position, and the offset includes at least one of the offset of the column in the vertical direction, the offset of the suspension device in the horizontal direction and / or the vertical direction, the offset of the detection bed in the horizontal direction and / or the vertical direction, the offset between the X-ray source and the center of the bed panel, the relative offset between the suspension device and the column, and the relative offset between the suspension device and the detection bed.

[0006] An exemplary embodiment of the present invention provides a motion compensation method for an X-ray imaging system. The X-ray imaging system includes a suspension device, a detection bed and a column, a detector is installed on the column, the detection bed has a bed panel, the suspension device includes an X-ray source, and a distance measuring unit is installed on the suspension device. The motion compensation method includes acquiring at least one distance information based on the distance measuring unit, acquiring at least one offset of the X-ray imaging system based on the at least one distance information, and performing compensation during the movement of the suspension device based on the at least one offset, wherein the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and the detector at at least one position, and the offset includes at least one of the offset between the column in the vertical direction, the offset of the suspension device in the horizontal direction and / or the vertical direction, the offset of the detection bed in the horizontal direction and / or the vertical direction, the offset between the X-ray source and the center of the bed panel, the relative offset between the suspension device and the column, and the relative offset between the suspension device and the detection bed.

[0007] An exemplary embodiment of the present invention provides an X-ray imaging system. The X-ray imaging system includes a suspension device, a detection bed, a column and a control unit, wherein a detector is installed on the column, the detection bed has a bed panel, the suspension device includes an X-ray source, and a distance measuring unit is installed on the suspension device, the control unit includes a distance acquisition unit and an offset calculation unit, the distance acquisition unit is used to acquire at least one distance information, the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and the detector at at least one position, and the offset calculation unit is used to acquire at least one offset of the X-ray imaging system based on the at least one distance information, the offset includes at least one of the offset between the columns in the vertical direction, the offset of the suspension device in the horizontal direction and / or the vertical direction, the offset of the detection bed in the horizontal direction and / or the vertical direction, the offset between the X-ray source and the center of the bed panel, the relative offset between the suspension device and the column, and the relative offset between the suspension device and the detection bed.

[0008] Other features and aspects will become apparent from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention may be better understood by describing exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which:

[0010] Figure 1 is a schematic diagram of an X-ray imaging system according to some embodiments of the present invention;

[0011] Figure 2 is a schematic diagram of a control unit in an X-ray imaging system according to some embodiments of the present invention;

[0012] Figure 3 is a schematic diagram of distance information acquisition in some embodiments of the present invention;

[0013] Figure 4 is based on Figure 3 A schematic diagram of an offset calculated from distance information and corresponding motion compensation;

[0014] Figure 5 is a schematic diagram of distance information acquisition in other embodiments of the present invention;

[0015] Figure 6 is a schematic diagram of distance calculation in some embodiments of the present invention;

[0016] Figure 7 is a schematic diagram of distance information acquisition in some other embodiments of the present invention;

[0017] Figure 8 is a flow chart of an offset detection method according to some embodiments of the present invention; and

[0018] Fig. 9 is a flowchart of a motion compensation method according to some embodiments of the present invention. DETAILED DESCRIPTION

[0019] The specific embodiments of the present invention will be described below. It should be noted that in the specific description of these embodiments, in order to provide a concise description, it is impossible for this specification to provide a detailed description of all the features of the actual embodiments. It should be understood that in the actual implementation of any embodiment, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet system-related or business-related restrictions, various specific decisions are often made, and this will also change from one embodiment to another. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the content disclosed by the present invention, some changes such as design, manufacturing or production based on the technical content disclosed in this disclosure are just conventional technical means, and should not be understood as insufficient content of this disclosure.

[0020] Unless otherwise defined, the technical or scientific terms used in the claims and the specification shall have the usual meaning understood by persons with ordinary skills in the technical field to which the invention belongs. The words "first", "second" and similar words used in the patent application specification and the claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "One" or "one" and other similar words do not indicate a quantitative limitation, but indicate the existence of at least one. "Include" or "comprises" and other similar words mean that the elements or objects appearing before "include" or "comprises" include the elements or objects listed after "include" or "comprises" and their equivalent elements, and do not exclude other elements or objects. "Connected" or "connected" and other similar words are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0021] Figure 1 FIG. 1 is a schematic diagram of an X-ray imaging system 100 according to some embodiments of the present invention. Figure 1 As shown, the X-ray imaging system 100 includes a suspension device 110, a wall stand device 120, and a test bed device 130. The suspension device 110 includes a longitudinal guide rail 111, a transverse guide rail 112, a telescopic cylinder 113, a trolley 114, a tube assembly 115, and a tube control device (console) 116.

[0022] For ease of description, in the present application, the x-axis, y-axis and z-axis are defined as the x-axis and y-axis are located in a horizontal plane and are perpendicular to each other, and the z-axis is perpendicular to the horizontal plane. Specifically, the direction of the longitudinal guide rail 111 is defined as the x-axis, the direction of the transverse guide rail 112 is defined as the y-axis direction, and the extension direction of the retractable cylinder 113 is defined as the z-axis direction, and the z-axis direction is the vertical direction.

[0023] The longitudinal guide rail 111 and the transverse guide rail 112 are vertically arranged, wherein the longitudinal guide rail 111 is installed on the ceiling, and the transverse guide rail 112 is installed on the longitudinal guide rail 111. The telescopic cylinder 113 is used to carry the ball tube assembly 115.

[0024] The pulley 114 is arranged between the transverse guide rail 112 and the telescopic cylinder 113. The pulley 114 may include a rotating shaft, a motor, a reel and other components. The motor can drive the reel to rotate around the rotating shaft, thereby driving the telescopic cylinder 113 to move along the z-axis and / or slide relative to the transverse guide rail. The pulley 114 can slide relative to the transverse guide rail 112, that is, the pulley 114 can drive the telescopic cylinder 113 and / or the ball tube assembly 115 to move along the y-axis direction. And the transverse guide rail 112 can slide relative to the longitudinal guide rail 111, thereby driving the telescopic cylinder 113 and / or the ball tube assembly 115 to move along the x-axis direction.

[0025] The telescopic cylinder 113 includes a plurality of cylinders with different inner diameters, and the plurality of cylinders can be sequentially sleeved in the cylinder located above them from bottom to top to achieve telescoping. The telescopic cylinder 113 can be telescopic (or movable) in the vertical direction, that is, the telescopic cylinder 113 can drive the ball tube assembly 115 to move along the z-axis direction. The lower end of the telescopic cylinder 113 is also provided with a rotating part, which can drive the ball tube assembly 115 to rotate.

[0026] The tube control device 116 is installed on the tube assembly 115. The tube control device 116 includes a user interface such as a display screen and control buttons for performing pre-shooting preparations, such as patient selection, protocol selection, and positioning.

[0027] The tube assembly 115 includes an X-ray source, and the collimator 117 is usually installed below the X-ray source. The collimator 117 includes four movable collimator blades, which are made of materials that can absorb X-rays, and the four collimator blades together form a square or a rectangle, and the four collimator blades form an opening in the middle after being surrounded, which is the opening of the collimator. The size of the opening of the collimator 117 determines the irradiation range of the X-rays, that is, the size of the exposure field of view (FOV). X-rays can pass through the opening of the collimator to irradiate the region of interest (ROI) of the object being tested, and other X-rays are absorbed by the blades to prevent the object being tested from absorbing too much unnecessary dose. Among them, the horizontal position of the X-ray source and the collimator 117 determines the position of the exposure field of view FOV on the object being tested.

[0028] The movement of the suspension device 110 includes the movement of the tube assembly along the x-axis, y-axis and z-axis, and the rotation of the tube assembly in the horizontal plane (the rotation axis is parallel to or coincident with the z-axis) and in the vertical plane (the rotation axis is parallel to the y-axis). In the above-mentioned movement, a motor is usually used to drive the corresponding component to rotate and thus achieve the corresponding movement or rotation, and the corresponding control component is generally installed in the pulley 114. The X-ray imaging system further includes a motion control unit (not shown in the figure), which can control the above-mentioned movement of the suspension device 110. Further, the motion control unit can receive a control signal to control the corresponding component to perform a corresponding movement, so as to drive the tube assembly to a preset or specified position.

[0029] The column device 120 includes a detector 121 (first detector), a column 122 and a connecting portion 123. The connecting portion 123 includes a support arm connected perpendicularly to the height direction of the column 122 and a rotating bracket installed on the support arm. The detector 121 is installed on the rotating bracket. The column device 120 further includes a detector driving device arranged between the rotating bracket and the detector 121. Under the drive of the detector driving device, the detector 121 moves along a direction parallel to the height direction of the column 122 on the plane supported by the rotating bracket. The detector 121 can also be further rotated relative to the supporting arm to form a certain angle with the column. The detector 121 has a plate-like structure, and its direction is variable so that the X-ray incident surface becomes vertical or horizontal according to the incident direction of the X-ray.

[0030] The detection bed device 130 includes an in-bed detector 131 (second detector). The selection or use of the first detector 121 and the second detector 131 can be determined based on the patient's shooting part and / or shooting protocol, and can also be determined based on the position of the object to be detected obtained by camera shooting, so as to perform shooting inspections in the supine or standing position. Figure 1 Only an example diagram of the column and the detection bed is shown. Those skilled in the art should understand that columns and / or detection beds of any form or arrangement may be selected, or only columns may be installed. The columns and / or detection beds do not limit the entire scheme of the present application.

[0031] The X-ray imaging system 100 further includes a display unit 150, which is operably connected to the camera unit and includes a user interface 151 for displaying real-time optical images. Specifically, the display unit 150 can include any form of display screen, which can be a main display screen located in a control room, a display screen of a tube control device 116 located in a scanning room, or a movable display, such as a tablet computer, a mobile phone, etc.

[0032] The X-ray imaging system further includes an input unit 160, which is used to receive user operations. The input unit 160 can include a touch screen, a keyboard, a mouse, a voice-activated control unit or any other suitable input device. The user can input operation signals / control signals to the control unit through the input unit 160.

[0033] The X-ray imaging system 100 further includes a control unit (not shown in the figure), which can be a main control unit located in the control room, a tube control device installed on a suspension device, a movable or portable control unit, or any combination of the above. The control unit may include a source control unit and a detector control unit. The source control unit is used to command the X-ray source to emit X-rays for image exposure. The detector control unit is used to select a suitable detector from a plurality of detectors and coordinate the control of various detector functions, for example, automatically selecting a corresponding detector according to the position or posture of the object to be detected, or performing various signal processing and filtering functions, specifically, for initial adjustment of the dynamic range, interleaving of digital image data, etc. In some embodiments, the control unit may provide power and timing signals for controlling the operation of the X-ray source and the detector.

[0034] In some embodiments, the control unit may also be configured to use the digitized signals to reconstruct one or more desired images and / or determine useful diagnostic information corresponding to the patient, wherein the control unit may include one or more dedicated processors, graphics processing units, digital signal processors, microcomputers, microcontrollers, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other suitable processing devices.

[0035] Of course, the X-ray imaging system may also include other numbers or configurations or forms of control units, for example, the control unit may be local (e.g., co-located with one or more X-ray imaging systems 100, such as in the same facility and / or the same local network); in other implementations, the control unit may be remote and therefore only accessible via a remote connection (e.g., via the Internet or other available remote access technology). In a particular implementation, the control unit may also be configured in a cloud-like manner and may be accessed and / or used in a manner substantially similar to accessing and using other cloud-based systems.

[0036] During the exposure process of the X-ray imaging system, it is usually necessary to move the suspension device in the vertical direction and / or horizontal direction relative to the column or the inspection bed. When, for example, the guide rail of the suspension device deviates during installation or later use, the movement trajectory of the retractable cylinder and the X-ray source installed on the guide rail also deviates. Alternatively, the inspection bed or the column deviates during installation or later use. These deviations will cause the acquired medical images of the inspected object to have noise or poor image quality. At this time, the user can only conduct on-site troubleshooting and calibration through on-site engineers. It takes a more complicated process to accurately know which component has deviated. Such a process is particularly complicated and time-consuming.

[0037] In response to such a situation, the applicant proposed an offset detection method (or device) and a motion compensation method (or device). By installing a ranging unit on the suspension device, the distances of the detectors of the bed panel and the column of the detection bed at multiple positions of the suspension device are obtained, and linear fitting is performed based on the multiple distance information. For example, the deviation (offset) of the relative distance between the suspension device and the detection bed can be obtained. Then the system can determine whether the deviation is less than a threshold value. When the deviation is less than the threshold value, the motion compensation correction method is started. In the subsequent movement of the suspension device, the detection bed and / or the column, motion compensation is performed to correct the offset. When the deviation is greater than the threshold value, the user can be prompted that an on-site engineer needs to conduct an on-site inspection. At the same time, the user can also be prompted which component has offset based on multiple distance information. This provides clear instructions or prompts for the on-site engineer's inspection and calibration.

[0038] Therefore, the X-ray imaging system 100 further includes a ranging unit 140, which can be aligned with the center of the detection bed or the center of the detector on the column, and can obtain the distance between the ranging unit and the target position (for example, the bed panel of the detection bed or the surface of the detector).

[0039] Figure 2 FIG. 2 shows a schematic diagram of a control unit of an X-ray imaging system of the present application. Figure 2 As shown, the control unit 200 includes a distance acquisition unit 210 and an offset calculation unit 220. The acquisition unit 210 can acquire at least one distance information based on the distance measuring unit, wherein the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and at least one position of the first detector. The offset calculation unit 220 can acquire at least one offset of the X-ray imaging system based on the at least one distance information, wherein the offset includes at least one of the offset between the columns in the vertical direction, the offset of the suspension device in the horizontal direction and / or the vertical direction, the offset of the detection bed in the horizontal direction and / or the vertical direction, the offset between the X-ray source and the center of the bed panel, the relative offset between the suspension device and the columns, and the relative offset between the suspension device and the detection bed.

[0040] Specifically, the distance acquisition unit 210 is connected to the distance measurement unit 140 to acquire at least one distance information.

[0041] In some embodiments, the ranging unit 140 includes at least one of a camera, a ranging sensor, a millimeter wave sensor, and an infrared sensor. When the ranging unit 140 is set toward the detection bed, the ranging unit 140 can send a detection signal and obtain the distance between the ranging unit 140 and the bed panel based on the signal reflected by the bed panel of the detection bed. For example, the distance between the ranging unit and the bed panel is obtained based on the time of sending the signal, the time of receiving the reflected signal, and the speed of signal transmission. For another example, the distance between the ranging unit and the bed panel can be calculated based on the frequency difference between the emission detection signal and the reception detection signal at the same time, and the linear increase slope of the emission detection signal frequency. Similarly, when the ranging unit 140 is set toward the first detector of the column, the ranging unit can also obtain its distance from the surface of the first detector according to the above method.

[0042] In some embodiments, the ranging unit 140 is a camera, which can obtain an optical image of the detection bed and / or column (which may or may not include a detector). Preferably, the ranging unit is a depth camera, and the ranging unit 140 can obtain the distance between the ranging unit 140 and the bed panel or the detector surface or the ground based on the depth information of the depth camera (such as a 3D point cloud). Specifically, the camera is installed on the side of the X-ray source at a certain angle α relative to the X-ray source, and the vertical distance of the ranging unit (or camera) relative to the bed panel or the detector surface can be calculated based on the depth information and the angle α.

[0043] In some embodiments, the distance acquisition unit 210 is further used to move at least one of the suspension device, the detection bed and the column to obtain at least one distance information. Specifically, the distance acquisition unit 210 can move the suspension device in the horizontal direction relative to the detection bed, move the suspension device and the detection bed in the vertical direction at the same time or forward and backward, move the suspension device and the column in the vertical direction at the same time or forward and backward, etc. The distance acquisition unit 210 is not limited to performing only one of the movements.

[0044] Figure 3 Schematic diagrams of distance information acquisition in some embodiments are shown. Figure 3 As shown, the suspension device is controlled to move from a first position 310 to a second position 320 along the horizontal direction (x-axis), and the distance information between the suspension device and the bed panel is obtained at multiple positions during the movement; and based on the multiple distance information, the relative offset between the suspension device and the detection bed is calculated. For ease of description, the length direction of the bed panel is the x-axis, and the width direction of the bed panel is the y-axis.

[0045] Specifically, the bed panel of the detection bed includes a first long side and a second long side arranged along the length direction (x axis), and a third short side and a fourth short side for connecting the first long side and the second long side, wherein the vertical direction where the midpoint of the third short side is located is defined as the first position 310, and the vertical direction where the midpoint of the fourth short side is located is defined as the second position 320. Of course, the positions of the connection points of the third short side and the first long side or the second long side can also be defined as the first position and the second position, respectively, or any position on the third short side can be defined as the first position, etc., and the definition is not specific. Since in the actual shooting process, the suspension device is usually moved in the middle position of the detection bed to perform positioning or shooting, therefore, during the detection, the suspension device is moved in the middle position of the detection bed to better measure the offset and perform motion compensation accordingly. Of course, in order to further obtain more offsets, the suspension device can be controlled to move multiple times in the horizontal direction, that is, the first horizontal movement is performed at a position close to the first long side, the second horizontal movement is performed at the middle position of the third short side, and the third horizontal movement is performed at a position close to the second long side, and the movement mode is not limited.

[0046] The distance acquisition unit 210 can control the suspension device to reach the first position 310, and then measure the first relative distance d1 between the distance measuring unit 140 and the bed panel at the first position 310, and then move the suspension device along the length direction of the bed panel (i.e., the direction of the x-axis), and obtain the distance between the distance measuring unit and the bed panel at intervals or at a fixed frequency. For example, the distance information can be collected every 10 cm. When reaching the first intermediate position, the second relative distance d2 between the distance measuring unit 140 and the bed panel is obtained, until reaching the second position 320, the nth relative distance d n , where n refers to the amount of distance information acquired by the ranging unit between the first position and the second position, or the frequency of the ranging unit acquisition, where n is an integer greater than or equal to 2. The ranging unit 140 can acquire distance information only at the first position and the second position, and of course, can also acquire distance information at the first position, the second position, and any position in between. The higher the acquisition frequency, the more accurate the calculated offset is.

[0047] The offset calculation unit 220 can obtain the first relative distance d1, the second relative distance d2, the nth relative distance d n Specifically, since the suspension device moves in the horizontal direction and the bed panel of the detection bed is also parallel to the horizontal direction, the distance measured during the translation of the suspension device should be a constant. Therefore, according to the distance information obtained by the distance acquisition unit, the relative offset between the suspension device and the detection bed can be determined.

[0048] Figure 4 Shown according to Figure 3 Schematic diagram of the offset calculated from the distance information and the corresponding motion compensation. Figure 4 As shown, assuming that the suspension device is controlled to move to the first position and the distance from the bed panel is d b At this time, the distance measuring unit can measure the distance from the bed panel. Assuming that the distance measured at this time is d1 = d b , continue to move in the horizontal direction, and continuously measure the distance between the distance measuring unit and the bed panel. When it is assumed to move to the middle position 315, the distance measured by the distance measuring unit from the bed panel is d a , and d a >d b When the suspension device passes the middle position and continues to move toward the second position, the distance between the distance measuring unit and the bed panel is d n =d b Therefore, the offset calculation unit 220 can perform linear fitting based on the distance information obtained by the distance acquisition unit 210 to obtain Figure 4 The curve 410 shown in FIG. 4 illustrates that when the suspension device moves to the intermediate position 315 (for example, a position 1 meter away from the first position), there is a distance d between the suspension device and the bed panel. a -d b Therefore, the offset calculation unit can obtain the corresponding offset by performing linear fitting or data analysis according to the measured distance information.

[0049] In some embodiments, when performing distance measurement, the suspension device is controlled to reach a specified position and stop moving, and the distance measuring unit can measure the distance information when the suspension device is in a stationary state, so that the distance information can be obtained more accurately.

[0050] In some embodiments, in addition to being able to control the suspension device to move from one end to the other along the length direction of the bed panel to measure the offset of the suspension device along the length direction (x-axis) of the bed panel, the suspension device can also be controlled to move from one end to the other along the width direction of the bed panel, that is, to measure the offset of the suspension device along the width direction (y-axis) of the bed panel.

[0051] Please refer back to Figure 2In some embodiments, the control unit further includes a judgment unit 230, which can judge whether the relative offset between the suspension device and the detection bed exceeds a threshold value. When the relative offset does not exceed the threshold value, the relative offset can be sent to the motion control unit 118 according to the result of linear fitting, and the motion control unit 118 can perform motion compensation or motion correction in the process of controlling the movement of the suspension device. Specifically, the motion control unit 118 can perform motion compensation when controlling the suspension device to move to a position with an offset according to the relative offset calculated by the offset calculation unit 220. For example, at a certain position, when the offset at this time is larger than that at other positions, when the motion control unit moves the suspension device to this position, it moves the offset downward according to the offset (reduces the distance between the suspension device and the detection bed or column), so that the distance between the X-ray source and the bed panel or column of the detection bed can be the same as the distance at other positions without an offset.

[0052] Please refer to Figure 4 , Figure 4 The curve 420 in FIG. 4 shows a schematic diagram of motion compensation. Compared with the relative offset curve 410 between the suspension device and the bed panel, the motion compensation curve 420 has a d when it is in the middle position 315. b -d a That is, when the relative offset is as shown in curve 410, during normal exposure or inspection, the motion control unit 118 can control the motion of the suspension device according to curve 420. For example, initially, the distance d between the suspension device and the bed panel is b To move the suspension device, when the suspension device reaches the middle position 315, the suspension device is moved down on the original basis so that the distance between the suspension device and the bed panel is 2d b -d a , so that the actual distance at position 315 is still d b When the suspension device leaves the middle position 315, the initial distance d is restored. b , that is, based on the relative offset, the distance between the suspension device and the bed panel is always kept constant (or constant).

[0053] Please return Figure 2When the judgment unit 230 determines that the relative offset between the suspension device and the bed panel exceeds the threshold, the relative offset can be sent to the display unit 150 to prompt the user to call an on-site engineer and prompt the user which part of the offset exceeds the threshold. The prompt can be provided to the user in a pop-up window, a prompt sign, a prompt voice, a warning sound, or any other suitable manner. In addition to prompting that there is an offset, the prompt information can also provide which part has an offset, for example, there is a large offset between the suspension device and the detection bed, there is a large offset between the suspension device and the column, and so on.

[0054] Figure 5 Schematic diagrams of distance information acquisition in other embodiments are shown. Figure 5 As shown, in some embodiments, the distance acquisition unit 210 controls the suspension device and the detection bed to move simultaneously from the third position to the fourth position in the vertical direction, and respectively acquires the distance information between the suspension device and the bed panel at multiple positions during the movement process, and the offset calculation unit 220 calculates the relative offset of the suspension device and the detection bed based on the multiple distance information.

[0055] Specifically, the third position and the fourth position are two positions separated by a certain distance in the vertical direction where the center 501 of the bed panel is located. The third position may be a position directly above the fourth position. Of course, the third position may also be a position directly below the fourth position. That is to say, the distance acquisition unit can move the suspension device and the detection bed from top to bottom in the vertical direction. Of course, it can also move from bottom to top in the vertical direction. The direction of movement is not limited.

[0056] Even though the third position and the fourth position mentioned above are limited to two positions in the vertical direction where the center of the bed panel is located, of course, they can also be set to any position in the vertical direction, as long as the suspension device and the detection bed can be moved upward or downward in the vertical direction. Of course, the movement in the center position is because the vertical direction of the suspension device is most often moved in the center position, and such offset acquisition is most commonly used.

[0057] Of course, the suspension device and the detection bed can also be moved upward or downward at multiple positions in the vertical direction, so that the relative offsets of multiple suspension devices and the detection bed in the vertical direction can be obtained. For example, the suspension device and the detection bed are moved simultaneously in the vertical direction where the center of the bed panel is located, and then the suspension device and the detection bed are moved simultaneously in the vertical direction where one end point of the bed panel is located, and so on.

[0058] In other embodiments, the distance acquisition unit can control the suspension device and the detection bed to move from the third position to the fourth position respectively, and obtain multiple distances between the suspension device and the bed panel during the movement, and calculate the vertical offset of the suspension device and the detection bed based on the multiple distance information. Specifically, first keep the detection bed still, control the suspension device to move up or down to obtain multiple distance information, then keep the suspension device still, control the detection bed to move up or down to obtain multiple distance information, and obtain the vertical offset of the suspension device and the vertical offset of the detection bed according to the multiple distance information obtained by the two movements. Of course, the relative offset between the suspension device and the detection bed can also be calculated according to the vertical offset of the suspension device and the detection bed.

[0059] In some embodiments, the suspension device is moved at a preset interval to obtain the distance between the ranging unit and the bed panel. For example, the distance is measured every time the suspension device moves 10 cm. The offset calculation unit can obtain the offset based on the actual measured distance information and the preset interval of movement.

[0060] In some embodiments, an indicator mark is provided on the bed panel, and the indicator mark is located at the center position 501 of the bed panel. Specifically, the indicator mark can be a "cross mark" or any other suitable mark, such as a QR code or a bar code. The indicator mark can be used to obtain whether the suspension device and the detection bed are offset in the horizontal direction in the vertical direction. Specifically, when the ranging unit is a camera, the distance acquisition unit can obtain the distance between the ranging unit and the indicator mark based on the distance information obtained by the camera and the optical image of the detection bed containing the indicator mark, and determine whether the horizontal distance between the ranging unit and the indicator mark is offset during the movement of the suspension device in the vertical direction, and then perform motion compensation for the offset.

[0061] In summary, in order to obtain the relative offset between the suspension device and the detection bed, first, the suspension device is controlled to move horizontally from one end of the detection bed to the other end, and then the suspension device is moved to the center of the bed panel, and then the detection bed and the suspension device are moved vertically from top to bottom or from bottom to top simultaneously or separately, so that the relative offset between the suspension device and the detection bed can be obtained respectively. Similarly, the relative offset can be judged whether it exceeds a threshold, so as to choose to perform motion compensation or prompt the user that maintenance is required.

[0062] In the actual shooting process, it is usually necessary to align the X-ray source with the center of the bed panel, that is, the position of the indicator mark. Since the position of the indicator mark is known and stored in the X-ray imaging system, the suspension device can be moved to the position aligned with the indicator mark, that is, it is considered that the X-ray source is aligned with the center of the bed panel, but sometimes the position is offset, and the X-ray source is not completely aligned with the indicator mark (that is, the center of the bed panel). Therefore, in some embodiments, the control unit of the present application can also be used to obtain the offset between the X-ray source and the center of the bed panel to determine whether the X-ray source is aligned with the center of the bed panel.

[0063] Specifically, the distance acquisition unit can also be used to acquire the distance between the X-ray source and the indicator mark on the bed panel, so that the offset calculation unit can calculate the offset between the X-ray source and the indicator mark. Figure 6 Schematic diagram of distance calculation in some embodiments of the present invention is shown. Figure 6 As shown, since the camera unit is installed on the side of the X-ray source (or collimator), and in order to enable the camera unit to align with the center of the detector, the camera unit will be fixed on the side of the collimator at a preset angle. Therefore, there is a fixed angle α between the camera unit and the side of the collimator. The thickness information from the camera to the indicator mark obtained by the camera image is dpp, and the distance from the camera to the bed panel is dppcos(α). According to the distance information from the camera to the bed panel and the positional relationship between the camera and the X-ray source, the horizontal offset d between the X-ray source and the bed panel can be calculated. offset , that is, the distance between the mapping point of the X-ray source on the bed panel and the indicator mark. When the measured horizontal offset is zero, it proves that the X-ray source is aligned with the center of the detection bed at this time, and no compensation or correction is required. When the measured horizontal offset is not zero, it is the same as the relative offset between the suspension device and the detection bed, and the movement or positioning compensation of the X-ray source or maintenance prompts can be performed.

[0064] In some embodiments, in addition to acquiring distance information by moving the suspension device or the detection bed, there may be other suitable methods. For example, the ranging unit is a wide-angle camera, which can acquire an optical image of the entire bed panel, calculate the distance information based on the size of the bed panel and the position of the camera, and so on.

[0065] Figure 7 Schematic diagrams of distance information acquisition in some embodiments are shown. Figure 7As shown, the distance calculation unit 210 can control the suspension device and the column to move from the fifth position 710 to the sixth position 720 at the same time, and obtain the distance information between the suspension device and the detector at multiple positions during the movement. The offset calculation unit 220 calculates the relative offset between the suspension device and the column based on the multiple distance information.

[0066] In some embodiments, the fifth position 710 and the sixth position 720 are two positions of the detector on the column respectively. The fifth position 710 may be above the sixth position 720. Of course, the fifth position 710 may also be below the sixth position 720. That is to say, the distance calculation unit 210 can control the simultaneous upward movement of the column and the suspension device, and can also control the simultaneous downward movement of the column and the suspension device, and the direction is not limited.

[0067] Specifically, the center of the detector also has an indicator mark 701, which can be a "cross" mark or any other type of mark, such as a QR code or a bar code, etc. In the process of the suspension device and the column moving up or down at the same time, the relative offset between the suspension device and the column can be determined based on the change in the distance between the ranging unit and the detector. Optionally, the offset of the column in the vertical direction can also be obtained based on the offset of the suspension device in the vertical direction.

[0068] Of course, based on the distance between the X-ray source or the distance measuring unit and the indicator mark at the center of the detector, the relative offset in the horizontal direction between the suspension device and the column can also be calculated. In addition, based on the distance between the X-ray source and the indicator mark, it can also be determined whether the X-ray source is aligned with the center of the detector. Specifically, the distance measurement or acquisition method, the offset calculation method and / or the motion compensation method are consistent with the above-mentioned method of the bed panel part.

[0069] In addition, the suspension device can be controlled to remain stationary and the detection bed can be moved in the vertical direction to obtain the vertical offset of the detection bed, or the suspension device can be moved to the ground of the alignment scanning room so that the ranging can measure the distance information from the ground to obtain the horizontal and / or vertical offset of the suspension device, etc.

[0070] Figure 8 FIG. 8 is a flow chart showing a method 800 for detecting an offset of an X-ray imaging system according to some embodiments of the present invention. Figure 8 As shown, the X-ray imaging method 800 includes step 810 and step 820 .

[0071] In step 810, at least one distance information is acquired based on the distance measuring unit, and the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and at least one position of the detector.

[0072] Specifically, the distance measuring unit includes at least one of a camera, a distance measuring sensor, a millimeter wave sensor, and an infrared sensor. Preferably, the distance measuring unit is a camera, which can obtain an optical image of at least one of the detection bed, the column, and the detector.

[0073] Specifically, the ranging unit can emit a detection signal and obtain the distance between the ranging unit and the bed panel or the detector based on the signal reflected from the surface of the bed panel or the detector of the detection bed. For example, the distance between the ranging unit and the bed panel or the detector can be obtained based on the time when the signal is emitted, the time when the reflected signal is received, and the speed of signal transmission. For another example, the distance between the ranging unit and the bed panel or the detector can be calculated based on the frequency difference between the transmitted detection signal and the received detection signal at the same time, and the linear increase slope of the transmitted detection signal frequency.

[0074] Specifically, before step 810, at least one of the suspension device, the detection bed and the column is further moved to obtain at least one distance information. Specifically, the movement includes moving the suspension device in a horizontal direction relative to the detection bed, moving the suspension device and the detection bed in a vertical direction simultaneously or front and back, and moving at least one of the suspension device and the column in a vertical direction simultaneously or front and back.

[0075] Specifically, the suspension device can be controlled to move from a first position to a second position in the horizontal direction, and / or the suspension device and the detection bed can be controlled to move from a third position to a fourth position in the vertical direction at the same time, and multiple distance information between the suspension device and the bed panel can be obtained at multiple positions during the movement, and based on the multiple distance information, the relative offset of the suspension device and the detection bed can be calculated.

[0076] Specifically, the suspension device and the detection bed can be controlled to move from the third position to the fourth position respectively, and multiple distance information between the suspension device and the bed panel can be obtained during the movement, and based on the multiple distance information, the vertical offset of the suspension device and the detection bed can be calculated.

[0077] Specifically, an indicator mark is provided on the bed panel, and the indicator mark is located at the center of the bed panel. Acquiring at least one offset of the X-ray imaging system includes acquiring the offset between the X-ray source and the indicator mark based on the distance information acquired by the camera and the optical image of the detection bed to determine whether the X-ray source and the indicator mark are aligned.

[0078] In step 820, based on at least one distance information, at least one offset of the X-ray imaging system is acquired, the at least one offset including at least one of an offset of a column in a vertical direction, an offset of a suspension device in a horizontal direction and / or a vertical direction, an offset of a detection bed in a horizontal direction and / or a vertical direction, an offset between an X-ray source and a center of a bed panel, a relative offset between a suspension device and a column, and a relative offset between a suspension device and a detection bed.

[0079] In some embodiments, after step 820, the method further includes performing motion compensation during the movement of the suspension device based on at least one offset. In other embodiments, after step 820, the method further includes performing an offset prompt of at least one of the suspension device, the detection bed, and the column based on at least one offset.

[0080] Fig. 9 FIG. 9 is a flow chart showing a motion compensation method 900 for an X-ray imaging system according to some embodiments of the present invention. Fig. 9 As shown, the X-ray imaging method 900 includes step 910 , step 920 and step 930 .

[0081] In step 910, at least one distance information is acquired based on the distance measuring unit, and the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel and / or the distance between the distance measuring unit and at least one position of the detector.

[0082] In step 920, based on at least one distance information, at least one offset of the X-ray imaging system is acquired, the at least one offset including at least one of an offset of a column in a vertical direction, an offset of a suspension device in a horizontal direction and / or a vertical direction, an offset of a detection bed in a horizontal direction and / or a vertical direction, an offset between an X-ray source and a center of a bed panel, a relative offset between a suspension device and a column, and a relative offset between a suspension device and a detection bed.

[0083] In step 930, based on at least one offset, motion compensation is performed during the movement of the suspension device so that the distance between the suspension device and the inspection bed, and the distance between the suspension device and the column remain unchanged.

[0084] The offset detection method can be tested according to the needs of the user, for example, when problems are found in the quality of medical images. Of course, it can also be performed right after installation. Of course, it can also be tested regularly, for example, before starting shooting every day, or every week, etc. The offset detection method of the present application can be set according to user preferences and can be customized.

[0085] The X-ray imaging system and the offset detection method and motion compensation method of the X-ray imaging system of some embodiments of the present invention can firstly obtain the relative offset between the components of the X-ray imaging system according to the change of the distance between the suspension device and the detector and / or the column, and can choose to perform motion compensation or repair according to the relative offset, so that when the offset is not very large, the motion compensation can be used for correction, which can reduce the number and cost of repairs. In addition, even if repairs are required, it can be determined which component has a problem according to the offset, and repairs can be carried out in a targeted manner. In addition, it is also possible to determine whether the X-ray source is aligned with the center of the detection bed or the detector according to the offset between the X-ray source and the indicator mark (on the bed panel of the detection bed or the detector of the column).

[0086] The present invention may also provide a non-transitory computer-readable storage medium for storing an instruction set and / or a computer program. When the instruction set and / or computer program is executed by a computer, the computer executes the above-mentioned image processing allocation method. The computer that executes the instruction set and / or computer program may be a computer of a medical imaging system or other device / module of a medical imaging system. In one embodiment, the instruction set and / or computer program may be compiled in a processor / control device of the computer.

[0087] Specifically, the set of instructions and / or computer program, when executed by a computer, causes the computer to:

[0088] Acquire at least one distance information based on the distance measuring unit, wherein the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and at least one position of the detector;

[0089] Based on the at least one distance information, at least one offset of the X-ray imaging system is acquired, wherein the at least one offset includes at least one of an offset of the column in a vertical direction, an offset of the suspension device in a horizontal direction and / or a vertical direction, an offset of the detection bed in a horizontal direction and / or a vertical direction, an offset between the X-ray source and a center of the bed panel, a relative offset between the suspension device and the column, and a relative offset between the suspension device and the detection bed.

[0090] The instructions described above may be combined into one instruction for execution, and any instruction may be split into multiple instructions for execution. In addition, the execution order of the instructions described above is not limited to the above order.

[0091] An exemplary embodiment of the present invention provides an X-ray imaging system.

[0092] As used herein, the term "computer" may include any processor-based or microprocessor-based system, including systems using microcontrollers, reduced instruction set computers (RISC), application specific integrated circuits (ASICs), logic circuits, and any other circuits or processors capable of performing the functions described herein. The above examples are exemplary only, and are thus not intended to limit the definition and / or meaning of the term "computer" in any way.

[0093] The instruction set may include various commands that instruct a computer or processor as a processing machine to perform specific operations, such as the methods and processes of various embodiments. The instruction set may take the form of a software program that may form part of one or more tangible non-transitory computer-readable media. The software may take various forms such as system software or application software. In addition, the software may take the form of a collection of independent programs or modules, a program module within a larger program, or a portion of a program module. The software may also include modular programming in the form of object-oriented programming. The processing of input data by the processing machine may be in response to operator commands, or in response to previous processing results, or in response to a request made by another processing machine.

[0094] As used herein, the term "computer" may include any processor-based or microprocessor-based system, including systems using microcontrollers, reduced instruction set computers (RISC), application specific integrated circuits (ASICs), logic circuits, and any other circuits or processors capable of performing the functions described herein. The above examples are exemplary only, and are thus not intended to limit the definition and / or meaning of the term "computer" in any way.

[0095] Some exemplary embodiments have been described above, however, it should be understood that various modifications may be made. For example, if the described techniques are performed in a different order and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways and / or replaced or supplemented by other components or their equivalents, suitable results may be achieved. Accordingly, other implementations also fall within the scope of protection of the claims.

Claims

1. A method for detecting a deviation of an X-ray imaging system, the X-ray imaging system comprising a suspension device, a detection bed and a column, the column being provided with a detector, the detection bed having a bed panel, the suspension device comprising an X-ray source, and a distance measuring unit being provided on the suspension device, the method for detecting a deviation comprising: Acquire at least one distance information based on the distance measuring unit, wherein the at least one distance information includes the distance between the distance measuring unit and at least one position of the bed panel, and / or the distance between the distance measuring unit and at least one position of the detector; as well as Based on the at least one distance information, at least one offset of the X-ray imaging system is acquired, wherein the at least one offset includes at least one of an offset of the column in a vertical direction, an offset of the suspension device in a horizontal direction and / or a vertical direction, an offset of the detection bed in a horizontal direction and / or a vertical direction, an offset between the X-ray source and a center of the bed panel, a relative offset between the suspension device and the column, and a relative offset between the suspension device and the detection bed.

2. The offset detection method according to claim 1, wherein: It further includes: moving at least one of the suspension device, the detection bed and the column to obtain the at least one distance information.

3. The offset detection method according to claim 2, wherein: Acquiring the at least one distance information includes: Control the suspension device to move from a first position to a second position in a horizontal direction relative to the bed panel, and / or control the suspension device and the detection bed to move simultaneously from a third position to a fourth position in a vertical direction, and obtain multiple distance information between the suspension device and the bed panel at multiple positions during the movement, and calculate the relative offset of the suspension device and the detection bed based on the multiple distance information.

4. The offset detection method according to claim 2, wherein: Acquiring the at least one distance information includes: The suspension device and the detection bed are controlled to move from the third position to the fourth position respectively, and multiple distance information between the suspension device and the bed panel are obtained respectively during the movement, and based on the multiple distance information, the vertical offset of the suspension device and the detection bed is calculated.

5. The offset detection method according to claim 1, wherein: The distance measuring unit includes at least one of a camera, a distance measuring sensor, a millimeter wave sensor, and an infrared sensor.

6. The offset detection method according to claim 1, wherein: The distance measuring unit is a camera, and the camera can obtain an optical image of at least one of the detection bed, the column and the detector.

7. The offset detection method according to claim 6, wherein: An indicator mark is provided on the bed panel, and the indicator mark is located at the center of the bed panel. Acquiring at least one offset of the X-ray imaging system includes acquiring an offset between the X-ray source and the indicator mark based on distance information acquired by the camera and an optical image of the detection bed, so as to determine whether the X-ray source and the indicator mark are aligned.

8. The offset detection method according to claim 1, wherein: Further comprising: performing motion compensation during movement of the suspension device based on the at least one offset.

9. The offset detection method according to claim 1, wherein: The method further includes: based on the at least one offset, providing a prompt for at least one offset of a suspension device, a detection bed, and a column.

10. A motion compensation method for an X-ray imaging system, the X-ray imaging system comprising a suspension device, a detection bed and a column, the column being provided with a detector, the detection bed having a bed panel, the suspension device comprising an X-ray source, and a distance measuring unit being provided on the suspension device, the motion compensation method comprising: Acquire at least one distance information, wherein the at least one distance information includes a distance between the distance measuring unit and at least one position of the bed panel, and / or a distance between the distance measuring unit and at least one position of the detector; Based on the at least one distance information, at least one offset of the X-ray imaging system is acquired, the offset comprising at least one of an offset between the columns in a vertical direction, an offset of the suspension device in a horizontal direction and / or a vertical direction, an offset of the detection bed in a horizontal direction and / or a vertical direction, an offset between the X-ray source and a center of the bed panel, a relative offset between the suspension device and the columns, and a relative offset between the suspension device and the detection bed; as well as Based on the at least one offset, compensation is performed during movement of the suspension device.

11. An X-ray imaging system, comprising: A suspension device, comprising an X-ray source, and a distance measuring unit is installed on the suspension device; a column on which a detector is mounted; A detection bed having a bed panel; as well as A control unit comprising: a distance acquisition unit, configured to acquire at least one distance information, wherein the at least one distance information includes a distance between the distance measuring unit and at least one position of the bed panel, and / or a distance between the distance measuring unit and at least one position of the detector; as well as An offset calculation unit is used to obtain at least one offset of the X-ray imaging system based on the at least one distance information, the offset comprising at least one of an offset between the columns in a vertical direction, an offset of the suspension device in a horizontal direction and / or a vertical direction, an offset of the detection bed in a horizontal direction and / or a vertical direction, an offset between the X-ray source and the center of the bed panel, a relative offset between the suspension device and the columns, and a relative offset between the suspension device and the detection bed.

Images