X-ray anti-scatter grid

Abstract

The present invention relates to an X-ray anti-scatter grid (10). The anti-scatter grid includes a plurality of primary partition walls (20) and a plurality of secondary partition walls (30). The plurality of primary partition walls includes an X-ray absorbing material. The plurality of primary partition walls are substantially parallel to one another. The plurality of secondary partition walls are positioned between adjacent pairs of walls of the plurality of primary partition walls, such that each secondary partition wall is positioned between adjacent pairs of walls of the plurality of primary partition walls. Each secondary partition wall of the plurality of secondary partition walls is formed from a plurality of columnar structures (40) extending between the plurality of primary partition walls. The plurality of columnar structures includes an X-ray absorbing material.

Description

[Technical field]

[0001] The present invention relates to an X-ray anti-scatter grid, a method for manufacturing an X-ray anti-scatter grid, and a method for manufacturing a plurality of secondary septa for an X-ray anti-scatter grid. [Background technology]

[0002] When scattered X-rays from a patient are collected by an imaging detector, they do not provide any additional information about the patient's anatomy, but degrade image quality by reducing the contrast and contrast-to-noise ratio (CNR) of the image. Therefore, anti-scatter grids (ASGs) have been used for decades in medical X-ray images (e.g., digital radiography, fluoroscopy images, 3D X-rays) and X-ray computed tomography (CT) images to absorb scattered X-rays and thereby improve image quality.

[0003] Although the use of 1D X-ray anti-scatter grids is well established in X-ray imaging, they suffer from poor anti-scatter performance (too high scatter-to-primary signal ratio (SPR) and too low CNR) for next generation (spectral) 3D X-ray cone-beam CT (CBCT) and CT imaging systems.

[0004] A key requirement for spectral X-ray imaging is to provide good discrimination between primary and scattered X-ray photons. Scattered X-ray photons have lower (indefinite) energy than the original primary X-ray photons and therefore reduce the spectral energy resolution of the X-ray detector if such photons are not absorbed in the anti-scatter grid. Therefore, 2D DMLS tungsten grids have been introduced for CT imaging. However, they suffer from the problem that their thick (nearly 100 μm) septa block the path towards the smaller pixel (<1 mm) CT detectors. Therefore, current 2D direct metal laser sintering (DMLS) tungsten CT ASGs are not compatible with smaller (<1 mm) pixel CT detectors due to their too thick (nearly 100 μm) septa. Another important drawback is the high manufacturing cost.

[0005] For 3D X-ray imaging (CBCT), an alternative 2D DMLS tungsten ASG grid has been proposed in WO2018194937A1. However, such a structure leads to grid line artifacts (GLA) in X-ray images caused by the thick (nearly 100 μm) septa. See, for example, T. Alexeev et al., "A novel total variation-based ring artifact suppression method for CBCT imaging with 2D anti-scatter grids," Medical Physics 46(5), 2189 (2019). Other disadvantages include high manufacturing costs and heavy weight.

[0006] EP0967619B1 describes a method for fabricating ASG in which a high-energy laser beam is projected through a phase mask onto an X-ray transparent substrate in order to ablate parts of the substrate material and then fill it with an X-ray absorbing material. The process is critically dependent on maintaining a uniform laser fluence (energy density distribution) for all substrate parts, which can lead to contamination of the substrate and optical components. Furthermore, the laser-induced local increase in substrate temperature is highly sensitive to the grid pattern and grid dimensions.

[0007] To aid in the visualization of the structure of such anti-scatter grids, the following figures are presented. Figure 2 shows the current state of the art 1D anti-scatter grid design for X-ray systems. Primary X-rays are indicated by "A" and scattered X-rays are indicated by "B". The septa 20 are made, for example, from lead or other high-Z material, with a spacing between adjacent walls of "D". Figure 3 shows a comparable 1D ASG, where there is space material "A" between the septa 20. The height of the septa in the direction of the incident X-rays is "h" and the thickness of each wall is "d". Figure 4 shows a state of the art ASG in an X-ray CT system. Figure 4A shows a 1D ASG, Figure 4B shows a folded molybdenum-based 2D ASG, and Figure 4C shows a tungsten-based 2D ASG. The large 2D ASG shown in Figure 4D represents a 3D printed 2D ASG (Dunlee DMLS tungsten CT grid, see https: / / www.dunlee.com / a-w / 3d-metal-printing / our-offer / anti-scatter-grids-for-ct.html), as detailed below. Summary of the Invention [Problem to be solved by the invention]

[0008] However, as mentioned above, these 2D structures are very difficult and expensive to manufacture / fabricate.

[0009] These issues need to be addressed.

[0010] An improved 2D x-ray anti-scatter grid would be advantageous. [Means for solving the problem]

[0011] The object of the present invention is solved by the subject matter of the independent claims, further embodiments are incorporated in the dependent claims. It is noted that the below described aspects and examples of the present invention also apply to the X-ray anti-scatter grid, the method for manufacturing the X-ray anti-scatter grid and the method for manufacturing a plurality of secondary partitions for the X-ray anti-scatter grid.

[0012] In a first aspect, 1. An X-ray anti-scatter grid, comprising: A plurality of primary bulkheads; Multiple secondary bulkheads and having the plurality of primary partitions include an X-ray absorbing material; the primary partition walls are substantially parallel to one another; the plurality of secondary bulkheads are positioned between adjacent pairs of walls of the plurality of primary bulkheads such that each secondary bulkhead is positioned between an adjacent pair of walls of the plurality of primary bulkheads; An x-ray anti-scatter grid is provided, wherein each secondary barrier of the plurality of secondary barriers is formed from a plurality of post-like structures extending between the plurality of primary barriers, the plurality of post-like structures comprising an x-ray absorbing material.

[0013] In other words, a new design is provided for a 2D anti-scatter grid that can be scaled to large areas, taking a 1D grid, for example made in a conventional manner using established 1D manufacturing techniques, for example with lead septa, and providing a 2D structure in addition to this. The 2D structure is provided through positioning x-ray absorbing columnar structures, which may for example comprise a high-Z material, where each extends laterally from one primary septum to the next in a direction approximately perpendicular to the direction of x-ray propagation, and these columnar structures form secondary septa. Thus, each secondary septum is located between adjacent walls of the primary septum, which is applied across the x-ray anti-scatter grid. Each secondary septum is formed from columnar structures that extend from one primary septum to an adjacent primary septum, and extend laterally in a direction approximately perpendicular to the direction of x-ray propagation, and thus the central axis down each columnar structure is approximately perpendicular to the primary septum.

[0014] In other words, starting from a conventional 1D grid based on primary partitions formed, for example, by lead lamellae, secondary grid partitions are introduced in the inter-spacer layer between the lead lamellae.

[0015] In this way, a 2D anti-scatter grid is provided in a cost effective manner, which builds on existing 1D grid fabrication, but provides secondary barriers that provide the 2D structure in a completely new manner, but via appropriately arranging pillar structures to form the secondary barriers.

[0016] In one example, the plurality of columnar structures extend in a direction substantially perpendicular to the plurality of primary partition walls.

[0017] It should be noted that the secondary partitions can only be perpendicular to the primary partitions at the center of a focused 2D grid (whereas the partitions in an unfocused 2D grid are perpendicular everywhere). In the case of a focused 2D grid, the primary and secondary walls become less and less perpendicular as one moves from the center to the corners of a large area focused 2D grid. This is meant to be "near perpendicular," and one skilled in the art will understand that this means for both focused and unfocused 2D grids.

[0018] In one example, the plurality of secondary partitions are contained within the plurality of sheets, with a sheet of the plurality of sheets located between each adjacent pair of walls of the plurality of primary partitions.

[0019] In one example, the sheets are one of paper, carbon, polymer, insulating material, composite material, reinforced material, light weight material, or aluminum or other light weight metal.

[0020] In one example, the secondary ribs are formed from lines of columnar structures.

[0021] In one example, a number of pillar structures are located within holes in a number of sheets.

[0022] In one example, two or more secondary septa in each sheet of the plurality of sheets are angled one to the other.

[0023] In one example, two or more secondary septa in each sheet of the plurality of sheets are angled toward a common point or line in space.

[0024] In a second aspect, a method of manufacturing an x-ray anti-scatter grid is provided, the anti-x-ray scatter grid including a plurality of primary partitions and a plurality of secondary partitions, the plurality of primary partitions including an x-ray absorbing material. The method includes the steps of: arranging the plurality of primary partitions substantially parallel to one another; forming a secondary partition of each of the plurality of secondary partitions from a plurality of columnar structures extending between the plurality of primary partitions; and positioning the plurality of secondary partitions between adjacent pairs of walls of the plurality of primary partitions such that the plurality of secondary partitions are positioned between adjacent pairs of walls of the plurality of primary partitions. The plurality of columnar structures include an x-ray absorbing material.

[0025] In one example, the method includes forming a plurality of secondary bulkheads within a plurality of sheets and disposing a sheet of the plurality of sheets between each adjacent pair of the plurality of primary bulkheads.

[0026] In one example, the method includes forming a plurality of columnar structures in holes in a plurality of sheets.

[0027] In one example, the method includes forming a plurality of columnar structures by printing in a plurality of holes.

[0028] In other words, secondary grid septa are introduced into the spacer layer between primary 1D septa, e.g. lead lamellae, where the secondary septa are formed from columnar structures. This is done by controlled removal of material from the inter-spacer layer (e.g. by laser ablation) followed by precise filling of the empty spaces with X-ray absorbing material (e.g. by inkjet / printing). Thus, proven 1D grid fabrication techniques can be utilized to create 1D ASG structures and laser drill and print techniques are used in entirely new ways to generate inter-spacer material for 1D structures that make the 1D structures into 2D anti-scatter grid structures.

[0029] Therefore, 2D ASGs can be fabricated by introducing minimal possible modifications to current 1D grid manufacturing processes, providing a cost-effective and flexible method of fabricating 2D ASGs.

[0030] In one example, the method includes machining backing at least one surface of each sheet of the plurality of sheets.

[0031] In a third aspect, a method of manufacturing a plurality of secondary partitions for an x-ray anti-scatter grid is provided, the method comprising forming each secondary partition of the plurality of secondary partitions from a plurality of post structures, the plurality of post structures including an x-ray absorbing material, the plurality of post structures of each secondary partition configured to extend between adjacent walls of a pair of a plurality of primary partitions of the x-ray anti-scatter grid.

[0032] In one example, the method includes forming a plurality of secondary septa into a sheet.

[0033] Advantageously, advantages provided by any of the above aspects apply equally to all of the other aspects, and vice versa.

[0034] The above aspects and examples will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0035] Exemplary embodiments will now be described with reference to the accompanying drawings. [Brief description of the drawings]

[0036] [Figure 1] 1 shows a schematic configuration of the structural features of an X-ray anti-scatter grid. [Diagram 2] 1 shows an example of a 1D X-ray anti-scatter grid. [Diagram 3] 1 shows an example of a 1D X-ray anti-scatter grid. [Figure 4A] FIG. 1 shows examples of 1D X-ray and 2D anti-scatter grids. [Figure 4B]FIG. 1 shows examples of 1D X-ray and 2D anti-scatter grids. [Figure 4C] FIG. 1 shows examples of 1D X-ray and 2D anti-scatter grids. [Figure 4D] FIG. 1 shows examples of 1D X-ray and 2D anti-scatter grids. [Diagram 5] FIG. 13 shows a schematic diagram of the processing of a sheet of fibrous interstitial material to provide a plurality of post-like structures for forming secondary septa of an X-ray 2D anti-scatter grid. [Figure 6] 1 shows an example of an X-ray 2D anti-scatter grid. [Figure 7] 1 shows an example of a spacer sheet having a plurality of pillar-like structures that form the secondary partitions of an X-ray 2D anti-scatter grid. [Figure 8] 1 shows angled secondary septa in the inter-spacer sheets of an X-ray 2D anti-scatter grid. [Figure 9] 1 shows an example of an inter-spacer sheet having a plurality of columnar structures forming secondary partitions of an X-ray 2D anti-scatter grid. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] FIG. 1 shows an example of an X-ray anti-scatter grid 10, where essential features are shown in solid lines and optional features are shown in dashed lines. The X-ray anti-scatter grid is a 2D anti-scatter grid and comprises a plurality of primary partitions 20 and a plurality of secondary partitions 30. The plurality of primary partitions comprises an X-ray absorbing material. The plurality of primary partitions are substantially parallel to one another. The plurality of secondary partitions are positioned between adjacent pairs of walls of the plurality of primary partitions such that each secondary partition is positioned between adjacent pairs of walls of the plurality of primary partitions. Each secondary partition of the plurality of secondary partitions is formed from a plurality of columnar structures 40 extending between the plurality of primary partitions. The plurality of columnar structures comprises an X-ray absorbing material.

[0038] In one example, the primary barrier is made of reed.

[0039] In one example, each columnar structure has a length approximately equal to the spacing between adjacent pairs of primary partitions.

[0040] In one example, each columnar structure has a circular cross-section.

[0041] In one example, each columnar structure has an elliptical cross section.

[0042] In one example, each columnar structure has a constant cross section.

[0043] In one example, each columnar structure has a varying cross-section.

[0044] According to one example, the plurality of columnar structures extend in a direction substantially perpendicular to the plurality of primary partition walls.

[0045] According to one example, multiple secondary barriers are provided in multiple sheets 50 . Located between each adjacent pair of the plurality of primary partition walls is a sheet of the plurality of sheets.

[0046] According to one example, the plurality of sheets is one of paper, carbon, polymer, insulating material, composite material, reinforced material, light weight material, or aluminum or other light weight metal.

[0047] According to one example, the secondary ribs are formed from lines of columnar structures.

[0048] In one example, each secondary rib comprises a zigzag line of columnar structures.

[0049] In one example, each secondary rib includes a plurality of lines of columnar structures.

[0050] According to one example, the pillars are located within holes 60 in the sheets.

[0051] In one example, the holes are formed by laser drilling / laser ablation.

[0052] In one example, a plurality of pillar structures are formed by printing into a plurality of holes.

[0053] In one example, a plurality of pillar structures are formed in the holes by inkjet printing.

[0054] In one example, a plurality of pillar structures are formed by screen printing into a plurality of holes.

[0055] According to one example, two or more secondary septa in each sheet of the plurality of sheets are angled one to the other.

[0056] According to one example, two or more secondary septa in each sheet of the plurality of sheets are angled toward a common point or line in space.

[0057] The manufacturing method can be used to make an X-ray anti-scatter grid. Once manufactured, the X-ray anti-scatter grid comprises a plurality of primary partitions and a plurality of secondary partitions comprising an X-ray absorbing material. The plurality of primary partitions comprises an X-ray absorbing material. The method includes arranging the plurality of primary partitions substantially parallel to one another. The method then includes forming each secondary partition of the plurality of secondary partitions from a plurality of columnar structures extending between the plurality of primary partitions, and disposing the plurality of secondary partitions between adjacent pairs of walls of the plurality of primary partitions such that each secondary partition is located between adjacent pairs of walls of the plurality of primary partitions.

[0058] In one example, the method includes forming a plurality of columnar structures such that the columnar structures extend in a direction substantially perpendicular to the plurality of primary partition walls.

[0059] According to one example, the method includes forming a plurality of secondary bulkheads in a plurality of sheets and disposing a sheet of the plurality of sheets between each adjacent pair of the plurality of primary bulkheads.

[0060] In one example, the sheets are one of paper, carbon, polymer, insulating material, composite material, reinforced material, light weight material, or aluminum or other light weight metal.

[0061] In one example, the secondary ribs are formed from lines of columnar structures.

[0062] According to one example, the method includes forming a plurality of post-shaped structures in holes in a plurality of sheets.

[0063] In one example, the method includes laser drilling a plurality of holes in a plurality of sheets.

[0064] According to one example, the method includes forming a plurality of pillar structures by printing a plurality of holes.

[0065] In one example, the ink or paste used for printing is loaded with tungsten and / or bismuth containing particles.

[0066] According to one example, the method includes machining backing at least one surface of each sheet of the plurality of sheets.

[0067] In one example, two or more secondary septa in each sheet of the plurality of sheets are angled one to the other.

[0068] In one example, two or more secondary septa in each sheet of the plurality of sheets are angled toward a common point or line in space. It will be appreciated that the columnar structures that may be used to create the secondary septa may be fabricated separately for the anti-scatter grid. Thus, a method of fabricating a plurality of secondary septa for an x-ray anti-scatter grid includes forming each secondary septa of the plurality of secondary septa from a plurality of columnar structures. The plurality of columnar structures include an x-ray absorbing material, and the plurality of columnar structures of each secondary septa are configured to extend between adjacent walls of a pair of the plurality of primary septa of the x-ray anti-scatter grid.

[0069] In one example, the method includes forming a plurality of columnar structures oriented to extend in a direction perpendicular to the plurality of primary partition walls.

[0070] According to one example, the method includes forming a plurality of secondary septa into a sheet.

[0071] In one example, the sheet is configured to be positioned between adjacent primary partitions of a 1D anti-scatter grid to form a 2D anti-scatter grid structure.

[0072] In one example, the sheet is one of paper, carbon, a polymer, an insulator material, a composite material, a reinforced material, a light weight material, or aluminum or other light weight metal.

[0073] In one example, the secondary ribs are formed from lines of columnar structures.

[0074] In one example, the method includes forming a plurality of columnar structures in a hole in the sheet.

[0075] In one example, the method includes laser drilling a plurality of holes in the sheet.

[0076] In one example, the method includes forming a plurality of columnar structures by printing in a plurality of holes.

[0077] In one example, the method includes machining backing on at least one surface of the sheet.

[0078] In one example, the method includes forming at least two or more secondary septa within the sheet at angles to one another.

[0079] In one embodiment, the method includes forming two or more secondary septa in the sheet at an angle toward a common point or line in space.

[0080] An X-ray anti-scatter grid, a method for manufacturing an X-ray anti-scatter grid, and a method for manufacturing a plurality of secondary partitions for an X-ray anti-scatter grid will now be specifically detailed with reference to Figures 5 to 9, including creating secondary partitions of an X-ray 2D anti-scatter grid in a spacer sheet.

[0081] FIG. 5 shows an example of processing a sheet of fiber interstitial material to provide a plurality of columnar structures to form secondary partitions of an X-ray 2D anti-scatter grid. Thus, in effect, an additional two-step roll-to-roll (R2R) process can be inserted into an existing 1D anti-scatter grid production line. This process includes the following steps, which are shown diagrammatically in the top and bottom of FIG. 5:

[0082] performing laser drilling (ablation) with laser beam "A" of cylindrical through-holes 60 in spacer / fiber layer 50 (preferably prior to paper (or other sheet material) planarization); filling the formed holes by inkjet or screen printing with an inkjet head "B" of high-Z material to form secondary barrier ribs 30 made of columnar structures, the ink or paste used being filled with tungsten and / or bismuth (or other X-ray absorbing material) particles; Optionally, curing and drying are performed. Includes.

[0083] FIG. 6 shows diagrammatically how a standard 1D grid composed of lead lamellae 20 is converted into a 2D grid. Secondary partitions 30 are introduced into the interspacer layer (e.g., a sheet of paper or aluminum) 50 by forming vertical lines of (cylindrical) holes drilled in the interspacer material and subsequently filling them with an X-ray absorbing (high-Z) material to form columnar structures 40. These secondary partitions 30 are oriented perpendicular to the primary partitions 20 composed of lead lamellae, thereby generating a second dimension in the 1D grid structure. The secondary partitions 30 formed by the columnar structures 40 are shown diagrammatically, in this example emphasizing the cylindrical nature of the structure, and can be oriented vertically, as shown in the lamella in the front left wall. However, as shown in FIG. 7, the columnar structures can be angled, and while the other secondary partitions shown in FIG. 6 are only shown in a representative manner, with their circular ends visible, this is not actually the case, as these ends are actually behind the lead lamella 20.

[0084] The design and distribution of holes across the inter-spacer layers can be varied to optimize ASG performance for a particular imaging application. For example, FIG. 7 shows two examples of secondary partitions 30 (top: non-focusing grid, bottom: focusing grid) made from columnar structures 40, where primary x-rays are indicated by "A" and scattered x-rays are indicated by "B". FIG. 7 shows that the primary x-ray transmission of the ASG can be increased by adapting the orientation of the hole line ("focal point") parallel to the incident primary x-ray beam over the entire length between the spacers (from one side of the ASG to the other). This is shown in more detail in FIG. 8, where the secondary partitions can be oriented toward the x-ray source to maximize throughput. Note that the secondary partitions of each inter-spacer do not need to be perfectly aligned between the inter-spacer layers, for example as shown in FIG. 6.

[0085] FIG. 9 shows various examples of hole line patterns from the top to the bottom of the interspacer layer. Each through hole forms a cylinder with a diameter of 10-50 μm (e.g., 25 μm) and a height of 50-500 μm (e.g., 200 μm), which is equal to the interspacer layer thickness. It should be understood that the cylinder does not have a constant cross section and can be wider at the front than at the back, and in fact, an elliptical shaped laser beam can be used to create elliptical shaped holes, thus creating elliptical shaped columnar structures to form the secondary septa. The filled hole lines form the secondary septa, which can be designed to maximize the absorption of scattered X-rays in the plane between the spacers (parallel to the lead lamellae) while still maintaining a large transmission of the first X-rays. Also, the introduction of secondary septa in the 1D grid allows the thickness of the primary septa (lead lamellae) to be reduced, while the ASG performance of the 2D grid is higher compared to the 1D grid.

[0086] It should be noted that other embodiments are possible: in addition to paper, other ASG interspacer materials are possible, such as polymers (e.g., polyetherimides, polyimides, and polycarbonates) or aluminum, which may have even better dimensional stability than paper.

[0087] In addition to hole lines, other designs of the secondary barrier of the interspacer layer are possible, such as dotted lines, dashed lines, zigzag and / or straight trenches. Also, the depth of the holes or trenches may be less than the thickness of the interspacer. For example, instead of a laser cut line of through holes from one side of the interspacer, it is possible to laser cut blind trenches from both sides of the interspacer to make the secondary barrier. Thus, a row of blind holes can be drilled from one side of the interspacer and a row of blind holes can be drilled from the other side, and these blind holes can be staggered, for example, below the interspacer. In R2R processing, even continuous through trenches across the entire width of the interspacer roll are possible if the interspacer is supported by a solid carrier foil. Certain secondary barrier designs can be manufactured more easily in sheet-to-sheet (S2S) or piece-to-piece (P2P) processing of interspacer material compared to R2R processing.

[0088] In terms of manufacturing technology, this is based on (1) laser perforation of paper (or plastic) in the packaging industry used for cigarette manufacturing (or fruit packing), and (2) large industrial equipment base used for inkjet printing used for flexible printed electronics. These two processes can be integrated to facilitate manufacturing, especially to achieve high registration accuracy of hole ablation and hole filling. For example, the basic components required (laser beam, optical components, inkjet head and ink supply) can be assembled in a single processing head, which, when combined with a controlled step-and-shoot movement of the spacers, requires only small lateral movements.

[0089] Performing the R2R process before inter-spacer planarization (here referring to thinning the incoming paper (or other sheet material) to the exact thickness required) can be beneficial as this can have a lower impact on the current 1D grid fabrication process. Furthermore, the subsequent planarization can remove unwanted laser debris and excess printed material from the surface of the inter-spacer material. Therefore, it is not necessary to laser drill holes or completely cut through the layer or space material before filling with high Z ink, because the back surface can be planarized to reveal the columnar structure before inserting the layer between the 1D primary partitions.

[0090] So, in summary, the following features / advantages of the 2D XL anti-scatter grid and its manufacturing method are: The fabrication is compatible with 1D grid manufacturing processes and High anti-scattering performance (low SPR, high CNR) and The thinness of the grid partitions allows the realization of high-resolution CT detectors (pixel pitch << 1 mm), which is difficult to achieve using 2D DMLS grids due to their thick (nearly 100 μm) partitions. Ability to cover large area X-ray and CT detectors and no grid tiling is required; A low-cost alternative to expensive 2D tungsten DMLS grids, Lower weight than heavy 2D tungsten DMLS grids and No grid line artifacts in the X-ray images due to thin grid septa in both directions (parallel and perpendicular to the lead lamellae) and no grid tiling; The thin grid septa ensure that no clinically relevant details are lost in the x-ray image. Allowing grid bending (perpendicular to the lead lamellae) for curved detectors Includes.

[0091] It should be noted that the embodiments of the present invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims, and other embodiments are described with reference to device type claims. However, those skilled in the art will understand from the above and following description that, unless otherwise indicated, any combination of features belonging to one type of subject matter, as well as any combination between features relating to different subject matters, is considered to be disclosed in this application. However, all features can be combined to provide synergistic effects that are more than the simple sum of the features.

[0092] While the invention has been illustrated and described in detail in the drawings and the foregoing description, such illustration and description are to be considered as illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the dependent claims.

[0093] In the claims, the word "comprise" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be interpreted as limiting the scope.

Claims

1. 1. An X-ray anti-scatter grid, comprising: A plurality of primary bulkheads; Multiple secondary bulkheads and having the plurality of primary partitions include an X-ray absorbing material; the primary partition walls are substantially parallel to one another; the plurality of secondary bulkheads are positioned between adjacent pairs of walls of the plurality of primary bulkheads such that each secondary bulkhead is positioned between an adjacent pair of walls of the plurality of primary bulkheads; each of the plurality of secondary partition walls is formed of a plurality of columnar structures extending between the plurality of primary partition walls, the plurality of columnar structures having an X-ray absorbing material, and the plurality of columnar structures extend in a direction substantially perpendicular to the plurality of primary partition walls; X-ray anti-scatter grid.

2. 10. The anti-scatter grid of claim 1, wherein the plurality of secondary partitions are provided in a plurality of sheets, a sheet of the plurality of sheets being disposed between each adjacent pair of walls of the plurality of primary partitions.

3. 3. The anti-scatter grid of claim 2, wherein the plurality of sheets are one of paper, carbon, polymer, insulating material, composite material, reinforced material, low weight material, or aluminum or other low weight metal.

4. 4. An anti-scatter grid according to claim 2 or 3, wherein the secondary barrier ribs are formed from a plurality of lines of the columnar structures.

5. 5. An anti-scatter grid according to any one of claims 2 to 4, wherein the pillar structures are located within holes in the sheets.

6. 6. The anti-scatter grid of claim 2, wherein two or more of the secondary partitions in each sheet of the plurality of sheets are angled relative to each other.

7. 7. The anti-scatter grid of claim 6, wherein two or more of the secondary partitions in each sheet of the plurality of sheets are angled toward a common point or line in space.

8. 11. A method of manufacturing an X-ray anti-scatter grid, the X-ray anti-scatter grid comprising a plurality of primary partitions and a plurality of secondary partitions, the primary partitions comprising an X-ray absorbing material, the method comprising the steps of: arranging the primary partitions substantially parallel to one another; forming each secondary partition of the secondary partitions from a plurality of columnar structures extending between the primary partitions; and arranging the secondary partitions between adjacent pairs of walls of the primary partitions such that each secondary partition is located between adjacent pairs of walls of the primary partitions, the columnar structures comprising an X-ray absorbing material, and the columnar structures extending in a direction substantially perpendicular to the primary partitions.

9. 9. The method of claim 8, wherein the method includes forming the plurality of secondary bulkheads in a plurality of sheets and positioning a sheet of the plurality of sheets between each adjacent pair of walls of the plurality of primary bulkheads.

10. The method of claim 9 , wherein the method comprises forming the plurality of post-like structures in holes in the plurality of sheets.

11. The method of claim 10 , wherein the method comprises forming the plurality of post structures by printing into the plurality of holes.

12. 12. The method according to claim 10 or 11, the method comprising the step of backing at least one surface of each sheet of the plurality of sheets by machining.

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