A method for generating data to reconstruct the spatial extent of a flat object using an X-ray system.

Abstract

To provide a method which realizes high resolution of 2D testing and allows information on positions of individual components of an object in terms of depth to be obtained.SOLUTION: Data for the reconstructing a volume in a flat object is generated using an X-ray system comprising a tube 1, detector 3, and the object 4 located therebetween. A laminography procedure, which is a combination of an object rotation and a translation, is carried out, where horizontal and vertical directions are observed independently, making a resulting trajectory resemble a cross-shape.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for generating data for reconstructing the spatial extent (Volumen) of a flat object using an X-ray system having a tube, a detector, and an object located between them. [Background technology]

[0002] The application field of this invention is X-ray-based material testing. Industrial parties such as those in the automotive industry and electronics manufacturers utilize X-ray systems in the context of X-ray-based material testing to test the properties of objects (particularly components). Here, using X-rays for imaging allows for the investigation of hidden structures without destroying the object.

[0003] This test is performed in an X-ray system having an X-ray tube (hereinafter referred to as the tube) and an X-ray detector (hereinafter also referred to as the detector) as the imaging system. The object to be inspected is placed between them. Some or all of these three designated components are movable in a translational and / or rotational manner, depending on the X-ray system. The entire apparatus is located within a radiation shielding cabin (hereinafter referred to as the cabin). Since the geometry of the image produced by this X-ray system depends on the focus of the tube, the tube will also be referred to simply as the focus below.

[0004] In non-destructive testing of large, flat components (e.g., printed circuit boards), very high magnification and resolution can be achieved in 2D images. However, since this is merely a projection of the entire object, all structures contained within the object overlap in the recorded image, and no conclusions can be drawn about the position of individual components in terms of depth. Computed tomography, which observes the object from many different angles distributed over 360°, allows for the acquisition of additional depth information. Subsequently, a three-dimensional object is reconstructed from these images, and as a result, the position of all components in space is determined. However, since the object must rotate 360 ​​degrees during this recording without colliding with the system's components, it is impossible to achieve the high magnification M seen in 2D testing, and this magnification M is determined by the distance from the focal point to the detector (FDD) and the distance from the focal point to the object (FOD) (M = FDD / FOD). Therefore, in the case of 2D inspection, the thickness of the object has a decisive impact on the achievable resolution, while in the case of CT images, the width of the object has the greatest limiting effect.

[0005] In the context of this application, "object" means an article whose two dimensions (surface area) are many times larger than its third dimension (referred to as depth).

[0006] From prior art, the following laminography procedures are known:

[0007] In circular / elliptic laminography, the tube and detector move along a circular or elliptical path, moving in opposite directions on parallel planes in each case. Therefore, this laminography procedure requires a system in which both the detector and the tube, and / or other objects (which can be moved similarly), have a vertical and horizontal axis. This allows for good sampling in Fourier space, but it cannot be used in systems lacking at least one of the required axes.

[0008] In translational laminography, the tube and detector are stationary, but the object is translated by a manipulator located at a fixed distance from the tube, traversing the entire field of view in one complete motion. This movement corresponds to the object rotating by the beam exit angle in the geometry of the parallel beam. This angle is limited by the size of the detector (if the detector is fully illuminated) and the distance between the tube and the detector. The following holds true: a larger beam exit angle results in better depth resolution of the system and better imaging of overlapping structures separately. However, this angle is minimized, especially at high magnifications when the detector is at its greatest distance from the tube, resulting in the lowest depth resolution of the system at this point.

[0009] Swing laminography, also known as limited-angle CT, differs from conventional CT in that the object rotates only by a limited angle controlled by the manipulator, and this angle is constrained by the geometry (the object must not collide with any system components during rotation). Here, the larger the range of angles that can be rotated, the better the depth resolution. However, especially at high resolution, it is necessary to bring the object as close to the light source as possible, which can result in a very small achievable laminography angle and consequently a very small depth resolution. This scanning procedure is particularly suitable for large, flat objects where large angles are not permissible. Due to the non-negligible aperture angle of the beam, some areas of the object may not be X-rayed perpendicularly, and as a result, the structures in those areas may not be properly resolved.

[0010] Linear laminography is very similar to swing laminography. While there is no object rotation, and instead the tube and detector can be translated using linear motors, rotation can also be achieved by linear movement opposite to that of the tube and detector (as in circular laminography). Unlike swing laminography, in this case the distance between all components remains constant and no actual rotation occurs, significantly reducing the likelihood of collisions between objects and system components. However, the laminography angle is limited by the range of movement of the tube and detector, and in the case of small CT systems, it is practically less than 15° to 20°. Furthermore, depending on the geometry of the object, the angular range can be highly asymmetrical. As a result, the depth resolution within the reconstructed spatial extent varies greatly, and in some parts of the object, the structure may not be properly resolved because it is not X-rayed perpendicularly. This behavior can also occur in swing laminography.

[0011] In rotational laminography, a flat object completes a full rotation around an axis perpendicular to the object's surface and tilted relative to the optical axis (either by actually tilting the axis of rotation or by tilting the detector). Therefore, this procedure requires a system with either a corresponding object rotation axis or a corresponding detector tilt axis. Systems with this design can achieve very large laminography angles in the range of approximately 60°, enabling very good depth resolution. However, systems without a corresponding tilt axis cannot utilize this procedure.

[0012] In the case of high-resolution 3D representation of large, flat components, 2D inspection and 3D reconstruction in the form of CT procedures each have different advantages and disadvantages. In the case of 2D images, all components of the object are superimposed, and it is not possible to clearly visualize which structure is in which plane. For example, in the case of a printed circuit board, when looking at the layers throughout the spatial extent of the CT, many structures (such as small holes, etc.) cannot be resolved. Also, in the case of conventional laminography procedures, as described above, within the spatial extent of the laminography, unlike CT, structures from the upper or lower layers can also be partially visualized, but only in a blurred display.

[0013] In the known laminography procedure that is the starting point of the present invention, at high magnification, projections of the object are recorded at various different angles. However, unlike CT, complete data of the object from 360° (or 180° + aperture angle) is not obtainable, and only data from a very narrow angular range is obtainable. From this, conclusions can be drawn about the positions of the individual components along the depth, but the resolution in this spatial direction is low and depends on the achieved laminography angle. The larger the angular range in which the projections can be recorded, the better the depth resolution. In a particular system, which type of laminography is selected depends greatly on the structure of the system.

Summary of the Invention

Problems to be Solved by the Invention

[0014] An object of the present invention is to provide a procedure capable of achieving high resolution in 2D inspection while at the same time obtaining information about the positions of the individual components of the object from the perspective of depth.

Means for Solving the Problems

[0015] The above object according to the present invention is achieved by a procedure having the features described in any one of claims 1 to 4. Advantageous designs are specified in the dependent claims.

[0016] According to these, the above objective is achieved by a procedure in which the overall trajectory of the components of the X-ray system includes two different sub-trajectories, such as a vertical sub-trajectory and a horizontal sub-trajectory. In each sub-trajectory, two equivalent options are possible. For example, the first sub-trajectory can be formed by two vertical movements of an object passing through a cone beam. These movements occur sequentially at two different vertically inclined positions of the imaging system, which consists of a tube and a detector, in which case the central radiation (zentrale Strahl) of the cone beam in the tube collides with the center of the detector, but not at a right angle. Alternatively, the first sub-trajectory can also be a vertical path of an object inclined at two different angles around the horizontal axis passing through the cone beam. In this case, the tube and detector face each other such that the central radiation (Zentralstrahl) of the cone beam collides with the detector perpendicularly at its coordinate zero point. The second sub-trajectory also has two equivalent movements. On the one hand, for example, the object can be rotated at two different angles around the vertical axis. Here, the geometry of a stationary imaging system is such that the central radiation strikes the detector perpendicularly at its coordinate zero point, and in each case, the object can be translated horizontally through the cone beam for each of the two angles. On the other hand, the object can be sequentially moved horizontally through the cone beam at two different horizontally inclined positions of the imaging system composed of the tube and the detector. In this case, the central radiation of the cone beam of the tube strikes the center of the detector, but not at a right angle. The combination of rotation and translation according to the present invention achieves better depth resolution compared to conventionally known methods. The four solutions in the independent claims are, in each case, possible combinations of one of the two first suborbitals and one of the two second suborbitals.

[0017] An advantageous development of the present invention is that the object is z o It is movable along the axis, and the detector is z d It provides the ability to move along an axis. As a result, the magnification can be changed according to the object being inspected.

[0018] An advantageous development of the present invention provides that the detector is fully illuminated by the cone beam during the acquisition of each X-ray image. This achieves a wider field of view.

[0019] A further advantageous development of the present invention is that the tube is rotatable about the y-axis and / or the tube is rotatable about the x-axis and / or the detector (is y d Rotatable around the axis, and / or, the detector (3) is x d The objective is to provide rotational capability around an axis. Even if the rotation angle is very large, and the aperture angle of the cone beam is no longer able to fully illuminate the detector, the rotation of the tube allows for full illumination of the detector.

[0020] An advantageous development of the present invention provides that the central radiation is always perpendicular to the surface of the detector. As a result, a constant magnification is achieved across the entire field of view.

[0021] An advantageous development of the present invention provides that the object passes through a cone beam in each partial orbit. This prevents a significant reduction in depth resolution at the edges of the object.

[0022] The symmetrical movement of components can be achieved by various different sub-trajectories. However, as a general rule, asymmetric movement is performed so that it can be specifically addressed for each individual case, and in each case the largest laminography angle can be used, thereby achieving the greatest depth resolution. The coordinates assigned to the axes in each case (e.g., y1 and y2) are not absolute but are oriented (i.e., vectors) in each case. Therefore, in order to realize such trajectories in the present invention, their coordinates may be absolutely equal as long as they are oriented in opposite directions. The same applies to the angle assigned to the axis of rotation (e.g., θ). l and θ r This also applies to ).

[0023] Further details and advantages of the present invention will be described in more detail with reference to examples of embodiments shown in the following drawings. [Brief explanation of the drawing]

[0024] [Figure 1] Figure 1 is a schematic diagram of the system geometry of the X-ray system, showing the possible translational and rotational axes. [Figure 2] Figure 2a is a schematic diagram of the first alternative example of the vertical trajectory. Figure 2b is a diagram showing two configurations divided into two parts, which are still shown as combined in Figure 2a. Figure 2c is a diagram showing the paths of peripheral radiation (Randstrahl) during object recording in the case of the vertical trajectory. [Figure 3] Figure 3a is a schematic diagram of the first alternative example of the horizontal trajectory. Figure 3b is a diagram of the two configurations divided into two parts, which are still shown as combined in Figure 3a. Figure 3c is a diagram showing the paths of peripheral radiation and additional radiation (weiteren Strahl) during object recording in the case of the horizontal trajectory. [Figure 4] Figure 4 shows the cross-sectional layers of a printed circuit board in the cases of translation only, rotation only, and a combination of translation and rotation. [Figure 5] Figure 5 shows the horizontal layer of the printed circuit board from Figure 4 in the cases of translation only, rotation only, and a combination of translation and rotation. [Modes for carrying out the invention]

[0025] Figure 1 schematically illustrates the system geometry of an X-ray system, which comprises a tube 1, an object 4, and a detector 3, with their respective possible translational and rotational axes shown. Below, only the translational and rotational axes important to the present invention will be described; the other axes shown in Figure 1 will not be discussed. The rotational axis has a scale (index) r, while the translational axis does not have a scale indicating translation.

[0026] The tube 1 defines a first Cartesian coordinate system starting from the focus 2, in which the central ray 14 of the cone beam 10 of the emitted X-rays forms the z-axis. The vertical direction is the y-axis, and (in addition to the z-axis that extends horizontally in the same way) the remaining horizontal direction is the x-axis. This y-axis can be formed not only as a translation axis but also as a rotation axis. Therefore, in the case of the non-rotated tube 1, in the case of a very inclined geometry where the detector 3 is outside the cone beam 10, the cone beam 10 may be repositioned. However, since rotation is not used in the described embodiments of the present invention, the indication of the rotation axis is omitted. Regarding the example of the embodiment of the present invention, the representative position of the tube 1 is referred to as the central position.

[0027] The detector 3 is a flat panel detector, which is formed as a square in FIG. 1, but is not limited thereto. The central ray 14 of the tube 1 collides with the center of the detector 3, and as a result, the origin of the second Cartesian coordinate system is defined. Each axis of this detector coordinate system has a scale d. The z d axis extends perpendicular to the horizontal surface of the coordinate system, and this is the same as the z-axis of the tube 1. The vertical direction extending within the detector 3 is the y d axis in this coordinate system, and the horizontal direction extending within the detector 3 is the x d axis. Regarding the example of the embodiment of the present invention, the representative position of the detector 3 is referred to as the central position.

[0028] An object 4 is located between the tube 1 and the detector 3, and its axis has a scale o. Regarding the example of the embodiment of the present invention, the position where the object 4 is represented is referred to as the neutral position 5, and in this neutral position 5, no rotation (nor translation) occurs. A third Cartesian coordinate system is assigned to the object 4, and the origin of this coordinate system is at a point on the central ray of the tube 1 (i.e., the z-axis). The z o axis extends horizontally along the z-axis at the neutral position 5 of the object 4. In the vertical direction, the y o axis extends, and the x o axis is the y-axis of the detector 3 at the represented neutral position 5 of the object 4.d It extends horizontally, parallel to the axis. In addition to the three translation axes, object 4 also has two rotation axes. x o Axis and y o Since all axes are also axes of rotation, x ro Axis and y ro These axes are also axes. These axes can also be replaced by equivalent movements of tube 1 and detector 3.

[0029] Figure 1 shows the distance from focus 2 to y o The distance to the axis (FOD) and the distance from the focal point 2 to the detector 3 along the central radiation 14 (FDD) are also shown, and based on these, the magnification M of the displayed geometry can be determined. As already mentioned above, this magnification M is equal to FDD / FOD.

[0030] As is obvious to those skilled in the art, the orientation of the axes in Figure 1 is not limiting, and the present invention includes all other orientations. That is, the present invention includes all other orientations, for example, when the z-axis extends vertically, or when the entire system is tilted by a (desired) angle around the x-axis and / or any of the other two axes (y-axis and z-axis).

[0031] The X-ray system further includes a storage device for storing data of individual X-ray images, a processing device for performing reconstruction of object 4 using the aforementioned data, and a display device (e.g., a monitor) connected to the processing device capable of displaying the reconstruction. The components, tube 1, object 4, and detector 3, are arranged within a radiation-shielded cabin to ensure that the X-rays used do not harm the health of people nearby. The aforementioned components, as well as their design, cooperation, and arrangement, are well known to those skilled in the art, and therefore further explanation thereof can be omitted.

[0032] For the trajectory according to the present invention shown in Figures 2 and 3, the requirements for the X-ray system are as follows: that the tube 1 is capable of y-translation (y-axis), and the detector 3 is capable of y-translation (y-axis). d (axis) and z translation (z dBoth axes (x) are operable (this is necessary for adjusting the magnification), and object 4 is able to do both of its three axes (x o , y o , z o In addition to translation along each of the axes, x o axis (at this point x) ro Also called the axis (this axis can also be replaced by the equivalent translation between tube 1 / object 4 and detector 3) and y o Axis (at this point, y) ro The X-ray system requires that rotation be possible around both the tube 1 / object 4 and the detector 3 (also referred to as the axis, which can also be replaced by the equivalent translation of the tube 1 / object 4 and the detector 3).

[0033] Figures 2a and 2b are schematic side views (i.e., essentially the x-direction view) of the three components of the X-ray system: tube 1, object 4, and detector 3. The vertical trajectory will be explained with reference to these figures, but the difference between the two figures is as follows: in Figure 2a, the two related positions are still shown together, while in Figure 2b, these two positions are shown separately. Both figures correspond to the yz plane.

[0034] Tube 1 emits a cone beam with a half-open angle φ, y d The entire detector 3 is illuminated along the axis. This overall illumination is present in both cases: when the detector 3 is located at its upper pole and when it is located at both its lower poles. The two poles of the detector 3 are y d They are on the axis, and each is y d1 or y d2 They are separated by a distance of y1 or y2. In the embodiment shown here, they are in opposite directions and equal, and therefore the design is symmetrical with respect to the z-axis. At the same time, tube 1 is moved to either its lower pole or upper pole. In the case of the two poles of detector 3, the coordinate origin of the first Cartesian coordinate system is on the y-axis, and with respect to the y-axis of the center position of tube 1, which is separated by a second distance y1 or a sixth distance y2, they are in opposite directions and equal, and therefore the design is symmetrical with respect to the z-axis. d1and y1, or distance y d2 And y2 coincide with each other depending on the magnification M(FDD / FOD). The axes of the central radiation 11 of the cone beam 10 are tilted at an angle of θ or -θ with respect to the z axis, respectively. In the example of the embodiment, the following values ​​are obtained: FDD = 1200 mm, FOD = 500 mm, y d1 = +547 mm, y d2 =-547mm, y1=-391mm, y2=+391mm, θ=38°, θ1=8°, θ'=46°.

[0035] Figure 2b clearly shows the translation of object 4. Object 4 is translated once in the configuration where tube 1 is at its lower pole and detector 3 is at its upper pole (left side of Figure 2b), and once in its mirror-reversal configuration, i.e., when tube 1 is at its upper pole and detector 3 is at its lower pole, y o The object is moved along the axis so as to pass completely through the cone beam 10. These poles, along with their distances, correspond to those shown in Figure 2a. Along this translation—whether performed from top to bottom or bottom to top—50 X-ray images are created for each movement of object 4 through the cone beam at predefined intervals of approximately 10 mm (i.e., 100 X-ray images for the entire vertical trajectory).

[0036] Figure 2c shows two peripheral radiation patterns 13, which are formed during the translation of object 4 in the situation shown on the left side of Figure 2b. These patterns in object 4 and z oThe angle with respect to the axis is θ', and in the case of the upper peripheral radiation 13 in the left-hand configuration of Figure 2b, this angle is the sum of the inclination angle θ and the upper partial opening angle θ1 of the cone beam 10 (shown on the left side of Figure 2c). Shown on the right side of Figure 2c is the corresponding pattern for the lower peripheral radiation 13 in the configuration on the left side of Figure 2b. The angle obtained here is the difference between θ and the lower partial opening angle θ2. The two partial opening angles θ1 and θ2 depend on the geometry of the X-ray system, particularly the FOD, FDD and θ. In the case of the right-hand configuration of Figure 2b, the result is a mirrored inversion of the pattern as shown in Figure 2c. Since θ' is 8° greater than θ (as described above), the laminography angle of the vertical trajectory is 46°, resulting in high depth resolution.

[0037] In addition to the vertical trajectory design described with reference to Figure 2, the present invention also provides a horizontal trajectory. The horizontal trajectory will be described below with reference to Figure 3.

[0038] Figures 3a and 3b are schematic top views (i.e., essentially the y-direction view) of the three components of the X-ray system: tube 1, object 4, and detector 3. The horizontal trajectory will be explained with reference to these figures, although in Figure 3a the two situations performing translational motion are still shown together, while in Figure 3b they are shown separately. These figures correspond to the xz plane.

[0039] While passing through the horizontal trajectory, the beam geometry always has a half-open angle φ, as described above for translational laminography and as shown in Figure 1. Here, the entire detector 3 is x d The light is continuously illuminated along the axis.

[0040] Object 4, from its neutral position, y o First rotation angle β around the axis l It can be rotated (left side of Figure 3b). On the right side of Figure 3b, object 4 is rotated in the opposite direction by a second rotation angle β (starting from the neutral position of object 4). rIt can be rotated. In the illustration, these two rotation angles are the same in absolute value (15°), but they point in opposite directions. As a result, a larger laminography angle is obtained, which is the half-open angle φ and the first rotation angle β. l / Second rotation angle β r This is equivalent to the sum of the two. This results in a greater depth resolution.

[0041] In Figure 3b, x o Translation along the axis is clearly visible. Object 4 is at a first rotation angle β, starting from the neutral position 5 of Object 4. l In the rotated configuration (shown on the left side of Figure 3b), once in its mirrored configuration, that is, from the neutral position 5 of object 4, object 4 rotates to a second rotation angle β r During rotation (shown on the right side of Figure 3b), the object is first moved parallel to the x-axis to completely pass through the cone beam 10. In this translation, 50 X-ray images are created for each movement of object 4 through the cone beam at predefined intervals—as in the case of vertical launch in this embodiment as well—approximately 10 mm intervals along the direction of movement. Since the direction of movement—whether the x-direction is positive or negative—is irrelevant, the required X-ray images can be created, for example, in both forward and backward movement.

[0042] Figure 3c shows the pattern of the upper peripheral radiation 13 in Figure 3b, and the pattern of additional radiation 12 located inside the cone beam 10 and shown below the central radiation 11 in this figure. The angle between these patterns and the z-axis in object 4 is φ+β for the upper peripheral radiation 13 relating to the situation on the right side of Figure 3b. lThis is shown on the left side of Figure 3c. The right side of Figure 3c shows the corresponding pattern for the radiation that extends slightly below the central radiation 13 in the left side of Figure 3b and is represented by a solid line. For the left side of Figure 3c, the resulting angle is 30°. Therefore, compared to translational laminography where the laminography angle is determined by the half-open angle φ (15° in this case), φ and the first rotation angle β l / Second rotation angle β r A larger laminography angle is obtained, corresponding to the sum of these factors. This enables greater depth resolution.

[0043] Subsequently, spatial extent data is generated from this projection using appropriate reconstruction procedures known to those skilled in the art.

[0044] Figure 4 shows exemplary cross-sectional layers (side views) of a printed circuit board—in this case, object 4—recorded using three different laminography procedures corresponding to the procedure in Figure 2. The illustrated structures (these are BGAs) should appear rounded from this orientation. However, the structures become blurred because the depth resolution of the laminography procedure is lower compared to CT scans. This is more pronounced when the laminography angle is small. On the left are the results of translational laminography (horizontal and vertical). Here, the depth resolution is limited by the X-ray opening angle (approximately 20°). In the center are the results of a combination of linear laminography (vertical) and swing laminography (horizontal). In this case, a wider range of angles is possible, resulting in better depth resolution (vertical: approximately 20°, horizontal: approximately 55°). On the right are the results for the procedure according to the present invention. In this case, the resulting laminography has the maximum angular range (vertical: approximately 40°, horizontal: approximately 75°), thus achieving the highest depth resolution. The actual circular shape in this structure is most accurately achieved by a combination of translation and rotation.

[0045] Figure 5 shows an exemplary reconstructed lateral layer of the printed circuit board in Figure 4, recorded using the same laminography procedure as shown in Figure 4, corresponding to the procedure in Figure 3. Here again, the different depth resolutions in different methods are clearly demonstrated. In this layer, only the ring-shaped structure should be visible, but the blurry structure of the round BGA in other layers becomes less visible as the laminography angle increases (from left to right). Furthermore, a drawback that can occur in linear laminography is demonstrated here, which can occur in the case of asymmetric angles (in the corresponding angular range, this should also be seen in swing laminography). When the smaller of the two angles (approximately 5° compared to approximately 15° in the other directions) is combined with the X-ray opening angle, the ring structure is not X-rayed perpendicularly across the entire area of ​​the image, resulting in a loss of accurate resolution. This is shown in the upper area of ​​the central image. Translating object 4 using the other two methods suppresses the occurrence of this artifact.

[0046] In summary, the present invention states the following: To increase the angular range of laminography, the two trajectories are combined in an appropriate manner, and as a result, object 4 is translated both horizontally and vertically throughout the entire field of view while rotated (in the vertical direction, the object can also be rotated by simultaneously displacing tube 1 and detector 3 - this can also occur horizontally if a corresponding axis exists). A laminography procedure combining the rotation and translation of the object is performed, and since the horizontal and vertical directions are observed independently of each other, the resulting trajectory resembles a cross shape.

[0047] To increase the angular range of laminography, the present invention combines two trajectories (vertical and horizontal) in an appropriate manner, resulting in object 4 being translated both horizontally and vertically throughout the entire field of view while rotated. This process approaches only the maximum possible angles in each of the four spatial directions (up, down, left, and right), and as a result, in the simplest case, object 4 moves twice both horizontally and vertically throughout the entire field of view. In each case, it is not absolutely necessary that the maximum possible angles be symmetrical in the horizontal and vertical directions. If the achievable angular range is greater than the opening angle of the cone beam 10, intermediate angles are also approached in addition to the maximum angle, and the number of translations throughout the entire field of view also increases accordingly. [Explanation of Symbols]

[0048] 1 (X-ray) tube 2 focus 3 (X-ray) detector 4 objects 5 Neutral position 10 Cornbeam 11 Central radiation (zentraler Strahl) 12 Additional radiation (weiteren Strahl) 13. Peripheral radiation (Randstrahl) 14 Central radiation (Zentralstrahl)

Claims

1. A method for generating data to reconstruct the spatial extent within a flat object (4) using an X-ray system, wherein the X-ray system comprises three imaging components: a tube (1), a detector (3), and an object (4) located between the tube (1) and the detector (3). The tube (1) has a focal point (2), which forms the coordinate origin of a first Cartesian coordinate system at the center of the tube (1) and emits a cone beam (10), the central radiation (14) of the cone beam (10) forms the z-axis of the first Cartesian coordinate system, and the x-axis of the first Cartesian coordinate system extends horizontally. At the center of the detector (3), the central radiation (14) collides perpendicularly with the detector (3), and this collision point forms the origin of the second Cartesian coordinate system, and the z coordinate system of the second Cartesian coordinate system ｄ The axis is the same as the z-axis of the center position of the tube (1) at the center position of the detector (3), and the x of the second Cartesian coordinate system. ｄ The axis extends horizontally, At the neutral position (5) of the object (4), the object (4) has a third Cartesian coordinate system, the origin of the third Cartesian coordinate system is the intersection of the central radiation (14) at the center position of the tube (1) and the rotation axis of the object (4) extending vertically, and at the neutral position (5) of the object (4), the z of the third Cartesian coordinate system ｏ The axis coincides with the central radiation (14) at the center position of the tube (1), and at the neutral position (5) of the object (4), the x of the third Cartesian coordinate system ｏ The axis extends parallel to the x-axis at the central position of the tube (1), At least two of the three imaging components are aligned along their respective y-axis; that is, the tube (1) is aligned along the y-axis corresponding to the center position of the tube (1), and the detector (3) is aligned along the y-axis corresponding to the center position of the detector (3). ｄ Along the axis, the object (4) is y corresponding to the neutral position (5) of the object (4). ｏ It is movable along the axis, The object (4) is x corresponding to the neutral position (5) of the object (4). ｏ It is movable along the axis and the y corresponds to the neutral position (5) of the object (4). ｏ It is rotatable around its axis, The following steps: a1) At least two of the three imaging components are such that the z-axis, z ｏ axis and z ｄ axis extend parallel to each other, and the x-axis, x ｏ axis and x ｄ axis extend parallel to each other, and in the yz plane, there is a first turning angle θ ｕ between the central ray (14) and the z-axis, and moving at least two of the three imaging components so as to have such a configuration, where the detector (3) has y ｄ１ coordinates and the tube (1) has y １ coordinates, and at the origin of the second Cartesian coordinate system, the central ray (14) collides with the detector (3), step After b1) a1), the object (4) y ｏ A step of moving along an axis from a first pole to a second pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the first pole is y ｏ１ It has coordinates, and the second pole is y ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After c1) and b1), at least two of the three imaging components are set to the z axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the yz plane, there is a second rotation angle θ between the central radiation (14) and the z axis. ｏ A step of moving at least two of the three imaging components so that a configuration exists, wherein the detector (3) is y ｄ２ It has coordinates, and the pipe (1) is y ２ It has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), where y ２ ≠y １ and y ｄ２ ≠y ｄ１ The steps, and After d1) and c1), the object (4) is moved y ｏ A step of moving along the axis from a third pole to a fourth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the third pole is y ｏ３ It has coordinates, and the fourth pole is y ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, As a result, it passes through a vertical trajectory, The following steps: e1) Moving the tube (1), the detector (3), and the object (4) such that the tube (1) and the detector (3) are located at their respective central positions, and the object (4) is located at its neutral position (5). After f1) e1), the object (4) is moved from the neutral position (5) of the object (4) to y ｏ First rotation angle β around the axis ｌ The step involves rotating the object (4) and moving it from the fifth pole to the sixth pole parallel to the x-axis of the tube (1) at the center position of the tube (1), wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the fifth pole is x ｏ１ It has coordinates, and the sixth pole is x ｏ２ The object (4) has coordinates, and at least partially, the X-ray passes through it, in steps, and After g1) f1), the object (4) is y ｏ A second rotation angle β around the axis ｒ (β ｒ ≠β ｌ ) Rotating the object (4) and moving it from the seventh pole to the eighth pole parallel to the x-axis of the tube (1) at the center position of the tube (1), wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the seventh pole is x ｏ３ It has coordinates, and the eighth pole is x ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, Therefore, it passes through the horizontal trajectory. method.

2. A method for generating data to reconstruct the spatial extent within a flat object (4) using an X-ray system, wherein the X-ray system comprises three imaging components: a tube (1), a detector (3), and an object (4) located between the tube (1) and the detector (3). The tube (1) has a focal point (2), which forms the coordinate origin of a first Cartesian coordinate system at the center of the tube (1) and emits a cone beam (10), the central radiation (14) of the cone beam (10) forms the z-axis of the first Cartesian coordinate system, and the x-axis of the first Cartesian coordinate system extends horizontally. At the center of the detector (3), the central radiation (14) collides perpendicularly with the detector (3), and this collision point forms the origin of the second Cartesian coordinate system, and the z coordinate system of the second Cartesian coordinate system ｄ The axis is the same as the z-axis of the center position of the tube (1) at the center position of the detector (3), and the x of the second Cartesian coordinate system. ｄ The axis extends horizontally, At the neutral position (5) of the object (4), the object (4) has a third Cartesian coordinate system, the origin of the third Cartesian coordinate system is the intersection of the central radiation (14) at the center position of the tube (1) and the rotation axis of the object (4) extending vertically, and at the neutral position (5) of the object (4), the z of the third Cartesian coordinate system ｏ The axis coincides with the central radiation (14) at the center position of the tube (1), and at the neutral position (5) of the object (4), the x of the third Cartesian coordinate system ｏ The axis extends parallel to the x-axis at the central position of the tube (1), At least two of the three imaging components are along their respective y-axis and x-axis, that is, the tube (1) along the y-axis / x-axis corresponding to the center position of the tube (1), and the detector (3) along the y-axis corresponding to the center position of the detector (3). ｄ axis / x ｄ Along the axis, the object (4) is y corresponding to the neutral position (5) of the object (4). ｏ axis / x ｏ It is movable along the axis, The following steps: a2) At least two of the three imaging components are z-axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the yz plane, there is a first rotation angle θ between the central radiation (14) and the z-axis. ｕ A step of moving at least two of the three imaging components so that a configuration exists, wherein the detector (3) is y ｄ１ It has coordinates, and the pipe (1) is y １ The system has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), step, After b2) a2), the object (4) y ｏ A step of moving along an axis from a first pole to a second pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the first pole is y ｏ１ It has coordinates, and the second pole is y ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After c2) and b2), at least two of the three imaging components are set to the z axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the yz plane, there is a second rotation angle θ between the central radiation (14) and the z axis. ｏ A step of moving at least two of the three imaging components so that a configuration exists, wherein the detector (3) is y ｄ２ It has coordinates, and the pipe (1) is y ２ It has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), where y ２ ≠y １ and y ｄ２ ≠y ｄ１ The steps, and After d2) c2), the object (4) is y ｏ A step of moving along the axis from a third pole to a fourth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the third pole is y ｏ３ It has coordinates, and the fourth pole is y ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, As a result, it passes through a vertical trajectory, The following steps: e2) At least two of the three imaging components are z-axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the xz plane, there is a first rotation angle β between the central radiation (14) and the z axis. ｌ A step of moving at least two of the three imaging components such that a configuration exists, wherein the detector (3) is x ｄ１ It has coordinates, and the pipe (1) is x １ The system has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), step, After f2) e2), the object (4) is x ｏ A step of moving along the axis from the fifth pole to the sixth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the fifth pole is x ｏ１ It has coordinates, and the sixth pole is x ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After g2) and f2), at least two of the three imaging components have the z-axis, z ｏ axis and z ｄ axis extending parallel to each other, and the x-axis, x ｏ axis and x ｄ axis extending parallel to each other, and in the xz plane, there is a second rotation angle β ｒ between the central ray (14) and the z-axis, and moving at least two of the three imaging components so as to have such a configuration, where the detector (3) has x ｄ２ coordinates and the tube (1) has x ２ coordinates, and at the origin of the second Cartesian coordinate system, the central ray (14) collides with the detector (3), where x ２ ≠ x １ and x ｄ２ ≠ x ｄ１ and x are not equal, a step, and After (h2)(g2), moving the object (4) from the seventh pole point to the eighth pole point along the x ｏ axis, wherein the X-ray image stored in the storage medium is created at a predefined distance along the movement, the seventh pole point has x ｏ３ coordinates, the eighth pole point has x ｏ４ coordinates, and the object (4) at least partially passes through the X-ray, step Therefore, it passes through the horizontal trajectory. The step involves, method.

3. A method for generating data to reconstruct the spatial extent within a flat object (4) using an X-ray system, wherein the X-ray system comprises three imaging components: a tube (1), a detector (3), and an object (4) located between the tube (1) and the detector (3). The tube (1) has a focal point (2), which forms the coordinate origin of a first Cartesian coordinate system at the center of the tube (1) and emits a cone beam (10), the central radiation (14) of the cone beam (10) forms the z-axis of the first Cartesian coordinate system, and the x-axis of the first Cartesian coordinate system extends horizontally. At the center of the detector (3), the central radiation (14) collides perpendicularly with the detector (3), and this collision point forms the origin of the second Cartesian coordinate system, and the z coordinate system of the second Cartesian coordinate system ｄ The axis is the same as the z-axis of the center position of the tube (1) at the center position of the detector (3), and the x of the second Cartesian coordinate system. ｄ The axis extends horizontally, At the neutral position (5) of the object (4), the object (4) has a third Cartesian coordinate system, the origin of the third Cartesian coordinate system is the intersection of the central radiation at the center position of the tube (1) and the rotation axis of the object (4) extending vertically, and at the neutral position of the object (4), the z of the third Cartesian coordinate system ｏ The axis coincides with the central radiation (14) at the center position of the tube (1), and at the neutral position (5) of the object (4), the x of the third Cartesian coordinate system ｏ The axis extends parallel to the x-axis at the central position of the tube (1), The pipe (1) is movable along the y-axis corresponding to the center position of the pipe (1), At least two of the three imaging components are along their respective x-axis, that is, the tube (1) along the x-axis corresponding to the center position of the tube (1), and the detector (3) along the x-axis corresponding to the center position of the detector (3). ｄ Along the axis, the object (4) is x corresponding to the neutral position (5) of the object (4) ｏ It is movable along the axis, The object (4) is y according to the neutral position (5) of the object (4) ｏ It is movable along the axis, and in each case, the x corresponds to the neutral position (5) of the object (4). ｏ It is rotatable around its axis, The following steps: a3) z axis, z ｏ Axis and z ｄ The axes coincide, as well as the x-axis and x ｏ Axis and x ｄ The three imaging components are moved so that their axes extend parallel to each other, and the object (4) is moved x ｏ A first rotation angle θ around the axis ｕ Rotate, step, After b3) a3), the object (4) y ｏ A step of moving along an axis from a first pole to a second pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the first pole is y ｏ１ It has coordinates, and the second pole is y ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After c3) and b3), the object (4) is x ｏ A first rotation angle θ around the axis ｕ A second rotation angle θ that is different from the first. ｏ Rotate, step, and After d3) c3), the object (4) is y ｏ A step of moving along the axis from a third pole to a fourth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the third pole is y ｏ３ It has coordinates, and the fourth pole is y ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, As a result, it passes through a vertical trajectory, The following steps: e3) At least two of the three imaging components are z-axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the xz plane, there is a first rotation angle β between the central radiation (14) and the z axis. ｌ A step of moving at least two of the three imaging components so that a configuration exists, wherein the detector (3) is x ｄ１ It has coordinates, and the pipe (1) is x １ The system has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), step, After f3) e3), the object (4) is x ｏ A step of moving along the axis from the fifth pole to the sixth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the fifth pole is x ｏ１ It has coordinates, and the sixth pole is x ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After g3) f3), at least two of the three imaging components are set to the z axis, z ｏ Axis and z ｄ The axes extend parallel to each other, as well as the x-axis, x ｏ Axis and x ｄ The axes are positioned so that they are parallel to each other, and in the xz plane, there is a second rotation angle β between the central radiation (14) and the z axis. ｒ A step of moving at least two of the three imaging components such that a configuration exists, wherein the detector (3) is x ｄ２ It has coordinates, and the pipe (1) is x ２ It has coordinates, and at the origin of the second Cartesian coordinate system, the central radiation (14) collides with the detector (3), where x ２ ≠x １ and x ｄ２ ≠x ｄ１ The steps, and After h3) g3), the object (4) is x ｏ A step of moving along the axis from the seventh pole to the eighth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the seventh pole is x ｏ３ It has coordinates, and the eighth pole is x ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, Therefore, it passes through the horizontal trajectory. The step involves, method.

4. A method for generating data to reconstruct the spatial extent within a flat object (4) using an X-ray system, wherein the X-ray system comprises three imaging components: a tube (1), a detector (3), and an object (4) located between the tube (1) and the detector (3). The tube (1) has a focal point (2), which forms the coordinate origin of a first Cartesian coordinate system at the center of the tube (1) and emits a cone beam (10), the central radiation (14) of the cone beam (10) forms the z-axis of the first Cartesian coordinate system, and the x-axis of the first Cartesian coordinate system extends horizontally. At the center of the detector (3), the central radiation (14) collides perpendicularly with the detector (3), and this collision point forms the origin of the second Cartesian coordinate system, and the z coordinate system of the second Cartesian coordinate system ｄ The axis is the same as the z-axis of the center position of the tube (1) at the center position of the detector (3), and the x of the second Cartesian coordinate system. ｄ The axis extends horizontally, At the neutral position (5) of the object (4), the object (4) has a third Cartesian coordinate system, the origin of the third Cartesian coordinate system is the intersection of the central radiation (14) at the center position of the tube (1) and the rotation axis of the object (4) extending vertically, and at the neutral position (5) of the object (4), the z of the third Cartesian coordinate system ｏ The axis coincides with the central radiation (14) at the center position of the tube (1), and at the neutral position (5) of the object (4), the x of the third Cartesian coordinate system ｏ The axis extends parallel to the x-axis at the central position of the tube (1), In each case, the object (4) corresponds to x ｏ Axis and y ｏ It is movable along the axis, and in each case, the x corresponds to the neutral position (5) of the object (4). ｏ and y ｏ It is rotatable around its axis, The following steps: a4) z axis, z ｏ Axis and z ｄ The axes coincide, as well as the x-axis and x ｏ Axis and x ｄ The three imaging components are moved so that their axes extend parallel to each other, and the object (4) is moved x ｏ A first rotation angle θ around the axis ｕ Rotate, step, After b4) a4), the object (4) y ｏ A step of moving along an axis from a first pole to a second pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the first pole is y ｏ１ It has coordinates, and the second pole is y ｏ２ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, After c4) and b4), the object (4) is x ｏ A first rotation angle θ around the axis ｕ A second rotation angle θ that is different from the first. ｏ Rotate, step, and After d4) c4), the object (4) is y ｏ A step of moving along the axis from a third pole to a fourth pole, wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the third pole is y ｏ３ It has coordinates, and the fourth pole is y ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, As a result, it passes through a vertical trajectory, The following steps: e4) Moving the tube (1), the detector (3), and the object (4) such that the tube (1) and the detector (3) are located at their respective central positions, and the object (4) is located at its neutral position (5), After f4) e4), the object (4) is moved from the neutral position (5) of the object (4) to y ｏ First rotation angle β around the axis ｌ The step involves rotating the object (4) and moving it from the fifth pole to the sixth pole parallel to the x-axis of the tube (1) at the center position of the tube (1), wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the fifth pole is x ｏ１ It has coordinates, and the sixth pole is x ｏ２ The object (4) has coordinates, and at least partially, the X-ray passes through it, in steps, and After g4)f4), the object (4) is y ｏ A second rotation angle β around the axis ｒ (β ｒ ≠β ｌ ) Rotating the object (4) and moving it from the seventh pole to the eighth pole parallel to the x-axis of the tube (1) at the center position of the tube (1), wherein the X-ray image stored in the storage medium is created along the movement at a predefined distance, and the seventh pole is x ｏ３ It has coordinates, and the eighth pole is x ｏ４ The object (4) has coordinates, and at least partially, the X-rays are passing through it, step, Therefore, it passes through the horizontal trajectory. The step involves, method.

5. The object (4) is z ｏ It is movable along the axis, and the detector (3) is z ｄ The method according to any one of claims 1 to 4, wherein the method is movable along an axis.

6. The method according to any one of claims 1 to 4, wherein the detector (3) is fully illuminated by the cone beam (10) during the acquisition of each X-ray image.

7. The tube (1) is rotatable around the y-axis and / or the tube (1) is rotatable around the x-axis and / or the detector (3) is y ｄ Rotatable around an axis, and / or the detector (3) is x ｄ The method according to any one of claims 1 to 4, wherein the device is rotatable about an axis.

8. The method according to claim 7, wherein the central radiation (14) is always perpendicular to the surface of the detector (3).

9. The method according to any one of claims 1 to 4, wherein the object (4) passes through the cone beam (10) in each partial orbit.

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