Tapered scintillator crystal module and method of using it

Abstract

A detection device is provided that includes a tapered scintillator module and a scintillator module that is tapered at least at the end that contacts the optical sensor, the taper depending on the position of the scintillator module within the active area of ​​the optical sensor. The tapering of the scintillator module may occur near the interface between the optical sensor and the module, minimizing light leakage to nearby pixels at the interface, yet allowing the detection device to retain high geometric efficiency and sensitivity to incident gamma rays due to the fact that the distal end does not need to be tapered. The distal end has the highest probability of gamma ray interaction based on the Beer-Lambert law for photoelectric absorption.

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims the benefit and priority of U.S. Provisional Application No. 63 / 073,785, filed on 2 September 2020, which is incorporated in its entirety by reference.

[0002] This disclosure generally relates to the field of radiographic imaging, and more specifically to positron emission tomography (PET). [Background technology]

[0003] PET imaging is a powerful technique primarily used for diagnosis, treatment selection, treatment monitoring, and research in cancer and neuropsychiatric disorders. Despite its high molecular specificity, quantitative nature, and clinical applicability, PET has not achieved its full potential as a leading molecular imaging modality, mainly due to its relatively insufficient spatial resolution. With this level of spatial resolution, current devices cannot measure target densities in small nodules related to pathogenesis and pathophysiology, as well as in many human and rodent brain regions.

[0004] PET detector systems require thick, high-density scintillator crystal modules to efficiently detect the high-energy (511 keV) gamma rays used in PET. High geometric efficiency (e.g., minimum gap or pitch between scintillator crystal modules) is crucial for achieving high gamma-ray detection sensitivity (and improving spatial resolution) in PET.

[0005] Depth-encoded PET detector modules have been developed to reduce parallax error (misalignment of coincidence lines) for long scintillator crystals. This reduces the component cost per detector ring for a small-diameter PET ring, increases the large solid angle range for sensitivity, and reduces the effect of annihilation gamma-ray non-collinearity on spatial resolution when using crystals with a small cross-sectional area. Further, depth-of-interaction (DOI) information can be used to resolve the convolution of optical photon transport in long crystals, thus improving timing resolution and spatial resolution uniformity. Further, known PET systems have a time-of-flight (TOF) readout function that improves signal-to-noise (SNR and sensitivity) by accurately estimating the gamma-ray origin position.

[0006] However, in known DOI-PET detector modules, such as DOI-PET detector modules having an optical waveguide coupled to the distal end (distal direction from the optical sensor) of the scintillator module, there is a trade-off between the spacing (gap) between scintillator modules and DOI / TOF performance. This is due to the fact that most optical photons interact with the sensor array from the edges of the scintillator module. Reducing the spacing (gap) between adjacent scintillator modules may increase light leakage to neighboring pixels and may harm TOF and DOI performance. Note that TOF can be correlated with DOI. However, this correlation is weakened by optical photon leakage (light leakage) to pixels adjacent to the primary pixel caused by imperfect coupling.

[0007] Further, if a part of the scintillator module overlaps with the gap (pixel gap) between optical sensors, signals may be lost along the edge.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

[0009] Accordingly, a particle detection device is disclosed which may comprise an array of optical sensors arranged as a two-dimensional array and a plurality of scintillator modules. There may be a first gap between adjacent optical sensors. Each optical sensor may correspond to a pixel. Each optical sensor may have an active region. At least one scintillator module may correspond to each optical sensor in the array. Each scintillator module may have a first end and a second end. The first end may be in contact with the corresponding optical sensor. There may be a second gap between adjacent scintillator modules. The second gap is defined as the minimum gap between adjacent scintillator modules. A scintillator module adjacent to the boundary of the active region of a corresponding optical sensor may have a tapered portion at the first end so that, when viewed along the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region. The first cross-sectional region is defined as being perpendicular to the longitudinal axis. The second gap may be smaller than the first gap.

[0010] In aspects of this disclosure, the second cross-sectional area at the second end may be larger than the first cross-sectional area. The second cross-sectional area is defined as being perpendicular to the longitudinal axis. In aspects of this disclosure, at least a portion of the second cross-sectional area at the second end may overlap with the first gap when viewed along the direction of the longitudinal axis.

[0011] In aspects of this disclosure, the first cross-sectional area may have a substantially circular shape.

[0012] In aspects of this disclosure, the scintillator module and the optical sensor may correspond one-to-one (one-to-one coupling). The first cross-sectional area may be rectangular, and all four sides at the first end may be tapered.

[0013] In other embodiments of this disclosure, the scintillator modules and optical sensors may correspond in a 4:1 ratio (4:1 coupling). In embodiments of this disclosure, the first cross-sectional region of each scintillator module may be defined by a plurality of sides, and at least two sides of the scintillator module facing each boundary of the active region may be tapered at the first end. In other embodiments, only the sides of the scintillator module facing each boundary of the active region may be tapered at the first end.

[0014] In aspects of this disclosure, the tapered portion may have a tapered length in a direction parallel to the longitudinal axis, and the tapered length may be less than one-third of the length from the first end to the second end in a direction parallel to the longitudinal axis. The tapered length may be the same for each scintillator module having a tapered portion.

[0015] In this embodiment, the scintillator module may have a longitudinal length of about 20 mm. In this embodiment, the taper length may be about 5 mm.

[0016] In aspects of this disclosure, the second cross-sectional area may be approximately 1.5 mm × approximately 1.5 mm, and the first cross-sectional area may be approximately 1.4 mm × approximately 1.4 mm. The active area may be approximately 3.0 mm × 3.0 mm.

[0017] In aspects of this disclosure, the device may further comprise an optical waveguide. The optical waveguide may be segmented. In aspects of this disclosure, the segmented optical waveguide may comprise a plurality of pseudoprisms. Each pseudoprism may be configured to change the direction of emission of radiation particles between the second ends of the scintillator module. In aspects of this disclosure, the segments of the optical waveguide may be offset from the optical sensors so that a first scintillator module in contact with a first optical sensor and a second scintillator module in contact with a second optical sensor are in contact with the same segments.

[0018] In embodiments of the present disclosure, the device may further include a reflector. In embodiments of the present disclosure, the reflector may be located on an optical waveguide. In other embodiments, the reflector may be located between segments of the optical waveguide. In yet another embodiment, the reflector may be located between each scintillator module, including in the space between the tapered portion and another scintillator module.

[0019] In aspects of the present disclosure, the second end of some scintillator modules may have a second tapered portion. The longitudinal length of the second tapered portion may be shorter than the longitudinal length of the tapered portion.

[0020] In aspects of this disclosure, since the segment is offset from the optical sensor, the side of the scintillator module that can be tapered at the second end may be different from the side of the scintillator module that can be tapered at the first end.

[0021] Furthermore, a particle detection device is disclosed which may comprise an array of optical sensors arranged as a two-dimensional array and a plurality of scintillator modules that may correspond to each optical sensor. There may be a first gap between adjacent optical sensors. Each optical sensor may correspond to a pixel. Each optical sensor may have an active region. Each scintillator module may have a first end and a second end. The first end may be in contact with its corresponding optical sensor. There may be a second gap between adjacent scintillator modules. The second gap is defined as the minimum gap between adjacent scintillator modules. At least a subset of the plurality of scintillator modules corresponding to each optical sensor may have a tapered portion at the first end. The position of the tapered portion may depend on the relative position of the scintillator modules within the active region and the respective boundaries of the active region. The second gap may be smaller than the first gap.

[0022] In aspects of this disclosure, the device may further include reflectors positioned between each scintillator module, including in the space between the tapered portion and another scintillator module.

[0023] In aspects of this disclosure, a scintillator module located at a corner of the active region may have at least two sides tapered at a first end so that a first cross-sectional area at the first end overlaps the active region when viewed along the longitudinal axis. The first cross-sectional area is defined as being perpendicular to the longitudinal axis. In other aspects, only two sides of the scintillator module located at a corner of the active region may be tapered at the first end.

[0024] In aspects of this disclosure, a scintillator module located between other scintillator modules that are aligned and positioned at the corner of an active region may have only one side tapered at its first end, so that, when viewed along the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region. This one side may face the boundary of the active region.

[0025] In aspects of this disclosure, a scintillator module having another scintillator module located between the scintillator module and the boundary of the active region may not have a tapered portion at the first end.

[0026] The patent file includes at least one color drawing. A copy of the patent including the color drawing will be provided by the Patent and Trademark Office upon request and payment of the required fees. [Brief explanation of the drawing]

[0027] [Figure 1] This is a cross-sectional view of a particle detection device according to an aspect of the present disclosure, which has a 4:1 coupling between a scintillator module and an optical sensor. [Figure 2]This is a diagram of an optical sensor according to an embodiment of the present disclosure, showing the tapered end (first end) and non-tapered end (second end) of the scintillator module to the optical sensor, which has a 4:1 coupling between the scintillator module and the optical sensor. [Figure 3] This is a diagram of a sensor array having scintillator modules, showing the tapered and non-tapered walls of the scintillator modules, with a 4:1 coupling between scintillator modules and optical sensors. [Figure 4] This diagram shows side-by-side diagrams of the non-tapered end (second end) and the tapered end (first end) of a scintillator module. [Figure 5A] This is a diagram of a known particle detection device. [Figure 5B] This is a diagram of a particle detection device according to an aspect of the present disclosure. [Figure 6] This is a cross-sectional view of a particle detection device according to another aspect of the present disclosure, which has a one-to-one coupling between a scintillator module and an optical sensor. [Figure 7] This is a diagram of a sensor array including a scintillator module, showing the tapered and non-tapered walls of the scintillator module, with a one-to-one coupling between the scintillator module and the optical sensor. [Figure 8] This is a cross-sectional view of a particle detection device according to another aspect of the present disclosure, which has a 9:1 coupling between a scintillator module and an optical sensor. [Figure 9] This is a diagram of a sensor array having tapered scintillator modules based on their relative position within the active region, with a 9:1 coupling between scintillator modules and optical sensors. [Figure 10] This is a cross-sectional view of a particle detection device according to another aspect of the Disclosure, in which the first and second ends of several scintillator modules are tapered according to an aspect of the Disclosure. [Figure 11] This is a diagram of a scintillator module manufactured according to an aspect of the present disclosure, having tapered first ends and a 4:1 coupling between the scintillator module and an optical sensor. [Figure 12]This is a diagram of a scintillator module manufactured according to an aspect of the present disclosure, having tapered first ends and a 4:1 coupling between the scintillator module and an optical sensor. [Figure 13] This is a diagram of a scintillator module manufactured according to an aspect of the present disclosure, having tapered first ends and a 4:1 coupling between the scintillator module and an optical sensor. [Figure 14] This figure shows a scintillator module manufactured according to an aspect of the present disclosure, having tapered first ends and a 4:1 coupling between the scintillator module and optical sensors, and also shows a sensor array. [Figure 15] This figure shows a scintillator module manufactured according to an aspect of the present disclosure, having tapered first ends and a 4:1 coupling between the scintillator module and optical sensors, and also shows a sensor array. [Figure 16] This figure shows other scintillator modules manufactured according to an embodiment of the present disclosure, in which several scintillator modules are tapered at the first and second ends, with tapered sides (parts) differing at the first and second ends, and there is a 4:1 coupling of scintillator modules to optical sensors. [Figure 17] The figure shows several scintillator modules manufactured according to an embodiment of the present disclosure, in which the tapered sides (parts) differ at the first end and the second end, and there is a 4:1 coupling of scintillator modules to optical sensors, with some scintillator modules tapered at the first and second ends, as well as a sensor array. [Figure 18] This graph shows the correlation between depth interaction position and time of flight for two different timestamping methods. [Figure 19A] This graph shows the calculated parameters for the depth interaction location and the energy-based DOI. [Figure 19B] This graph shows the calculated parameters for the depth interaction location, based on timing, and using a single timestamp. [Figure 19C] This graph shows the calculated parameters for the depth interaction location, using a timing-based approach with three timestamps (averaged). [Modes for carrying out the invention]

[0028] According to aspects of this disclosure, some scintillator modules have a tapered end closest to the optical sensor 120, thereby reducing unexpected photon (light) leakage to nearby or adjacent pixels (different optical sensors). According to aspects of this disclosure, these scintillator modules have an end closest to the optical sensor when viewed in the longitudinal direction that tapers to the gap G between sensors. D This avoids overlap and reduces signal loss along the edges. At the same time, geometric efficiency (determined by the gap between adjacent modules and the minimum gap between adjacent modules) is maintained, and high gamma-ray detection sensitivity is achieved. The distal end of the scintillator module does not need to be tapered and may therefore be full width, so the distal end has the highest probability of gamma-ray interaction based on Lambert-Beer's law for photoelectric absorption, thus maintaining efficiency.

[0029] According to aspects of this disclosure, the scintillator modules may be arranged in different configurations. For example, Figure 1 shows an example of a scintillator module configuration. In Figure 1, there are four scintillator modules 100 for each optical sensor 120. However, Figure 1 is a cross-sectional view showing only two scintillator modules per optical sensor 120. Four scintillator modules are shown in Figures 2 and 3.

[0030] Each scintillator module 100 may be manufactured from a lutetium yttrium osciorthosilicate (LYSO) crystal. The scintillator module 100 is not limited to LYSO, and other types of crystals that emit photons of light in the presence of incident gamma radiation, such as lutetium osciorthosilicate (LSO), may be used. One end of the scintillator module 100 may be in contact with the optical sensor 120 (first end 107).

[0031] In aspects of this disclosure, the optical sensor 120 may be a silicon photomultiplier tube (SiPM). In other aspects of this disclosure, the optical sensor 120 may be an avalanche photodiode (APD), a single-photon avalanche (SPAD), a photomultiplier tube (PMT), or a silicon avalanche photodiode (SiAPD). These are non-limiting examples of solid-state detectors that may be used. Although the optical sensor 120 is shown separately in Figure 1, the optical sensor 120 may be manufactured as a single package or plate with space (active region 300) between the sensors. Examples of packages or plates are shown in Figures 14 and 15 (sensor array 300). The number of optical sensors 120 (pixels) in device 1 may be based on the application and size of the PET system. In aspects of this disclosure, the optical sensor 120 may be positioned as a two-dimensional array, such as an 8x8 array. The two-dimensional array is formed in a plane perpendicular to the longitudinal axis of the scintillator module. The direction of the longitudinal axis is shown in Figure 1. For the sake of explanation, the longitudinal axis is the z-direction, and the 2D array is in the xy-direction. The optical sensor 120 has a sensor gap G D The array is positioned so that 117 (shown as a double arrow in Figure 1) is present. The four points in Figure 1 represent other sensors / modules within the array, which are not specifically illustrated.

[0032] In an 8x8 array, the scintillator module 100 is positioned as a 16x16 array (to achieve a 4:1 coupling between module 100 and optical sensor 120). The scintillator module 100 has a module gap G s It is arranged to have 119. Module gap G as referenced herein s This defines the minimum distance between adjacent scintillator modules or nearby scintillator modules (non-tapered sections) in the x-direction or y-direction. Module gap G s 119 examples are shown in Figure 1 using double arrows.

[0033] According to the aspects of this disclosure, the module gap G s 119<Sensor gap G D 117, and as a result, detection device 1 has high gamma-ray detection sensitivity. Consequently, an overlapping region 121 is shown in Figure 1, where the scintillator module 100 (when viewed in the longitudinal direction) is in the sensor gap G D It overlaps. The overlapping region 121 is shown between the two dotted lines.

[0034] The second end 109 (the distal end relative to the optical sensor 120) of the scintillator module 100 is in contact with the optical waveguide 110. The optical waveguide 110 may be any optical waveguide, such as a single uniform waveguide. The optical waveguide 110 is configured for intercrystalline light shared between scintillator modules 100, including between modules 100 each associated with different pixels or different optical sensors 120.

[0035] In other embodiments, the optical waveguide 110 may be a segmented optical waveguide 110A, as shown in Figure 5B. Each segment is configured to change the direction of particle emission between several scintillator modules. An example of a segmented optical waveguide is described in U.S. Patent Application No. 2020 / 0326434, the disclosure of which is incorporated herein by reference. The position of each segment is offset from the optical sensor 120 (in either the x-direction or the y-direction). As shown in Figure 5B, the segments of the optical waveguide are in contact with scintillator modules associated with a first optical sensor (e.g., sensor 1) and another scintillator module associated with a second optical sensor (e.g., sensor 2), thereby allowing light to be shared between adjacent pixels. In embodiments of this disclosure, each segment is coupled only with scintillator modules belonging to different optical sensors (pixels).

[0036] Each segment of the optical waveguide 110A may include a pseudoprism. In aspects of the present disclosure, the pseudoprism may be substantially shaped as at least one of at least one of at least one prism, at least one antiprism, at least one frustum of a cone, at least one triangle, at least one cupola, at least one parallelogram, at least one wedge, at least one pyramid, at least one frustum of a pyramid, at least one part of a sphere, at least one cuboid, and at least one pyramid.

[0037] Using segments improves the intercrystal light sharing ratio, and therefore improves both crystal identification and DOI resolution. In some aspects of this disclosure, differently designed pseudoprisms may be used depending on the position of the segments in the scintillator array. For example, there may be three different designs: corner pseudoprisms, central pseudoprisms, and edge pseudoprisms, where the corner pseudoprisms and edge pseudoprisms are designed to reduce edge and corner artifacts.

[0038] Some scintillator modules 100 have a tapered portion 105. In an aspect of the present disclosure, the tapered portion 105 is located at a first end 107. As shown in FIG. 1, the wall of the scintillator module 100 is angled inwardly. Angle A is parallel to the longitudinal axis and is defined by a (sharp) perpendicular line extending along the wall or surface of the scintillator module (also parallel to the longitudinal axis) and the tapered wall. In an aspect of the present disclosure, by the tapering, the first end 107 (contact end) does not overlap with the sensor gap G D (alternatively, the first end only overlaps with the active region of the sensor 120). FIG. 1 shows that the tapered wall (the wall between the start of the taper and the sensor surface) is linear (line profile), but in other aspects the wall may be arcuate (curved profile). The first end 107 only overlaps with the active region 310 of the optical sensor 120 and does not overlap with the gap G between the sensors D So, the signal loss along the edge due to photon leakage is reduced.

[0039] In an aspect of the present disclosure, as the angle A, an angle is selected such that the first end 107 does not overlap with the sensor gap G D At the same time, the angle A is not so steep that photons are reflected from the surface of the tapered wall and retained (and not detected) within the scintillator module 100.

[0040] In another aspect of this disclosure, a starting point for the taper may be selected to maintain high sensitivity. For example, if the taper starts near the second end 109 and tapers gradually all the way to the first end 107, the overlap region 121 is small, and sensitivity may decrease because, as noted above, most of the interaction between optical photons and the sensor array originates from the edges of the scintillator module. Starting the taper near the second end 109 extends the distance between adjacent scintillator modules over a longer length along the longitudinal axis. In some aspects of this disclosure, the taper may start closer to the first end 107 than to the second end 109. For example, the taper may start before reaching the midpoint between the first end 107 and the second end 109. In other aspects of this disclosure, the taper may start about one-third of the way between the first end 107 and the second end 109 (closer to the first end 107).

[0041] As shown in Figure 1, device 1 may include a reflector 115. The reflector 115 may contain barium sulfate BaS04. In other embodiments, the reflector 115 may contain other reflective materials. In embodiments of this disclosure, a reflector 115A may be used between each scintillator module 100. Furthermore, in embodiments of this disclosure, the space formed by the tapered portion 105 may be filled with the reflector 115A. In the figure, to emphasize that the gap formed by the tapered portion may be filled with a reflector, the reflector 115 in that space is shown with a different shade than the reflector 115 in the gap (119) between the scintillator modules. The reflector 115A may be made of the same material as the reflector 115, such as barium sulfate BaS04, but is not limited to this material. This material has high spatial performance without reducing energy and timing resolution. When a segmented optical waveguide 110A is used, the reflector 115 may fill any space between the segments of the segmented optical waveguide 110A.

[0042] Figure 2 shows the relationship between the first end of the scintillator module (first end 107, which is tapered), the second end of the scintillator module (second end 109, which does not need to be tapered), and the optical sensor 120. As can be seen in Figure 2, the second end 109 has a portion (active region) that does not overlap with the sensor 120, while the first end 107 (which is tapered) overlaps with the sensor 120 and does not have a portion that does not overlap with the sensor 120.

[0043] In aspects of this disclosure, the walls of the scintillator module 100 facing the boundary or edge of the optical sensor 120 may be tapered. Figure 3 shows an example of a sensor array 300. The four dots represent other sensor / scintillator modules in the array (four sensors are specifically shown for illustrative purposes). Each sensor 120 has an active region 310 (which defines a pixel). Each active region has four sides defined by an edge or boundary. As shown in Figure 3, the walls of the scintillator module facing the boundary or edge of the active region (boundary wall 305) may be tapered. These walls are indicated in Figure 3 using dotted lines. On the other hand, the walls of the scintillator module that do not face the boundary or edge of the active region (inner walls) do not have to be tapered (non-tapered walls 315) in order to maintain high gamma-ray detection sensitivity.

[0044] Figure 4 shows an example of the relative sizes of a tapered end (first end 107) and a non-tapered end (second end 109) side by side. The first end 107 has a first cross-sectional region 400, and the second end 109 has a second cross-sectional region 405. The first cross-sectional region 400 and the second cross-sectional region 405 are regions perpendicular to the longitudinal axis (for example, regions in the xy plane). The first cross-sectional region 400 is the region that contacts the optical sensor 120. The second cross-sectional region 405 is the region that contacts the optical waveguide 110 / 110A.

[0045] As shown in Figure 4, the sensor array 300 is 8×8 (as noted above) and has 4:1 coupling (thus resulting in a 16×16 scintillator module array). As can be seen in Figure 4, the space 410 between the scintillator modules, each associated with a different optical sensor, is the scintillator module gap G s It is larger than 119. This space 410 is the sensor gap G D It may be 117 or more. In other words, the first cross-sectional area 400 does not need to reach the boundary of the active area 310 (pixels). The spacing between scintillator modules 100 within group 415 (at the first end) is smaller than the spacing between groups (space 410) (between groups 415). As shown in Figure 4, group 415 has four scintillator modules 100, forming, for example, a 4:1 coupling.

[0046] Figures 2 to 4 show the first end (first cross-sectional region 400) having a substantially rectangular shape. However, in other embodiments of the present disclosure, the first cross-sectional region may have other shapes. The shape may be a function of the manufacturing process and tolerances. For example, the shape may be substantially circular. For example, the tapered portion 105 may be conical.

[0047] If the shape is circular, the tapered portion 105 may only correspond to the portion facing the boundary or edge of the active area, such as half of the circle. The shape may also be a squirkle, a Reuleaux triangle, a spherical triangle, a hexagon, a pentagon, an octagon, etc.

[0048] Figures 5A and 5B show a detection device including a non-tapered scintillator module 100A and a portion of a detection device including several modules of a scintillator module 100 having a tapered portion 105 according to an embodiment of the present disclosure. As shown in Figure 5A, the first end extends beyond the optical sensor (overlapping with the gap between sensors), which can cause light leakage and reduce sensitivity. In contrast, according to an embodiment of the present disclosure, the first end 107 is tapered (having a tapered portion 105), and the first end 107 is in the gap G DSince it does not extend inward and exceed the active area 310 of the optical sensor 120, unexpected leakage is reduced, for example, to a minimum, and in some cases, the leakage may become lower than the background noise level and therefore undetectable.

[0049] The detection device 1 may have other configurations (other than 4:1 coupling). For example, the detection device 1A may have a 1:1 coupling configuration as shown in Figures 6 and 7. The scintillator module 100B and the optical sensor 120 are arranged as a two-dimensional array. The scintillator module 100B has a scintillator module gap G S It has 119A. The gap size may differ from the gap size in a 4:1 coupling configuration. When viewed in the longitudinal axis direction, the scintillator module 100B has a sensor gap / pitch G D Scintillator module 100B as overlapping region 121A, overlapping with 117. In Figure 6, two sensors 120 (e.g., sensor 1 and sensor 2) are illustrated for illustrative purposes, and the other sensors are represented by four points.

[0050] The scintillator module 100B may have a tapered portion 105A at the first end 107A. In this configuration, since there is only one scintillator module 100B per optical sensor 120, all walls (sides) of the scintillator module 100B extending in the longitudinal axis direction (z-direction) are boundary walls (near the boundary or edge of the active region, and therefore all walls may be tapered). Figure 7 shows an example of a sensor array 300, specifically showing four sensors for illustrative purposes. Other sensors in the array are represented by four dots. In Figure 7, the tapered boundary wall 305 is identified using a dotted line.

[0051] Figure 7 shows that four walls are tapered, but in other embodiments of this disclosure, fewer than four walls may be tapered. For example, if an optical sensor is located at a corner of a sensor array, walls (sides) that are not adjacent to other sensors 120 do not need to be tapered.

[0052] Figures 8 and 9 illustrate another detection device 1B according to an aspect of the present disclosure. Detection device 1B has a 9:1 coupling configuration. Nine scintillator modules 100 correspond to one sensor 120. In Figure 8, two sensors 120 (e.g., sensor 1 and sensor 2) are shown for illustrative purposes, and the other sensors are represented by four dots.

[0053] The scintillator modules 100 / 100A and the optical sensor 120 are arranged as a two-dimensional array. The scintillator modules 100 / 100A are located in the scintillator module gap G S It has 119B. The gap size may differ from the gap size in a 4:1 coupling configuration or a 1:1 coupling configuration. When viewed in the longitudinal axis direction, the scintillator module 100 has a sensor gap G D It has an overlapping region 121B that overlaps with 117.

[0054] In aspects of this disclosure, some scintillator modules may be tapered at the first end 107B. The tapering may be based on the relative position of the scintillator module to the active region 310, for example, a position adjacent to the boundary or edge of the active region 310. If scintillator module 100A is not adjacent to the boundary or edge of the active region 310, scintillator module 100A does not need to be tapered. However, if scintillator module 100 is located adjacent to the boundary or edge of the active region 310, one or more walls of scintillator module 100 may be tapered. In aspects of this disclosure, the tapered portion 105B may be located at the first end 107B. As above, the taper is located at the first end 107B (even if there may be an overlapping region 121B distal to the tapered portion 105B) over the sensor gap G D It is provided so that there is no overlapping area or portion with 117.

[0055] In aspects of this disclosure, the number of tapered walls may depend on the position of the scintillator module 100 relative to the active region 310. For example, as shown in Figure 9, a scintillator module 100 located at a corner of the active region 310 may have two tapered walls (two boundary walls 305). The boundary walls 305 are shown by dotted lines in Figure 9. In other aspects, if the scintillator module 100 is not located at a corner but is still adjacent to the boundary or edge of the active region 310, the scintillator module 100 may have only one of its tapered walls (for example, the wall facing the boundary or edge). In other aspects, other walls (non-boundary walls) may be tapered as needed.

[0056] In the example shown in Figure 9, four scintillator modules 100 have two tapered walls (corner modules), four scintillator modules 100 have one tapered wall (scintillator modules between corner modules), and one scintillator module 100A is not tapered.

[0057] In the example shown in Figure 9, the array specifically shows four optical sensors 120, while the other optical sensors are represented by dots.

[0058] According to aspects of this disclosure, other scintillator module 100 / sensor 120 configurations, such as 16:1 coupling or asymmetric coupling such as 2×1, may be used.

[0059] In aspects of this disclosure, multiple walls (sides) of the scintillator module 100 are tapered, and the amount of taper is substantially the same as that which provides symmetry. However, when manufacturing the scintillator module 100 with tapered walls (sides), there may be tolerances in the amount of taper due to limitations in the manufacturing process. The term “substantially the same” as used herein also includes differences in size resulting from manufacturing and tolerances.

[0060] The phrase “the side or wall is tapered” may refer to a portion or surface of the scintillator module 100 being tapered. For example, if the scintillator module is cylindrical and has only curved surfaces in the longitudinal direction (z-direction), a portion of the scintillator module 100 (the portion facing the boundary or edge of the active region) may be tapered.

[0061] Figure 10 shows a cross-sectional view of a particle detection device 1D according to another aspect of the present disclosure. According to this aspect of the present disclosure, both the first end 107 and the second end 109A may have tapered portions with respect to several scintillator modules 100C (for example, the first tapered portion 1005 and the second tapered portion 1000). The tapering of the first end 107 has been described above and will not be described in further detail.

[0062] In this aspect of the disclosure, the second end 109A may be tapered to reduce signal loss along the edge due to misalignment of the segmented optical waveguide 110A and the scintillator module 100C. Slight misalignment may be an artifact of the manufacturing process where perfect alignment (the edge of the scintillator module perfectly coincides with or is aligned with the edge of the optical waveguide segment) is rarely performed. When there is misalignment and a portion of the second end of the scintillator module extends beyond the segment of the segmented optical waveguide 110A, photons may be lost (not reflected). As noted above, since the majority of optical photon-optical sensor interactions originate from the edge of the scintillator module, photon loss from the edge can degrade the performance of the PET. The second end 109A is tapered and has a second tapered portion 1000, thereby preventing the second end 109A from extending beyond the segment, and reducing edge-side losses caused by misalignment between the segmented optical waveguide 110A and the scintillator module 100C.

[0063] Generally, the misalignment between the segmented optical waveguide 110A and the scintillator module 100C is small, for example, less than 1 mm. The angle of taper B is defined as the angle (acute angle) between the tapered wall and a virtual line (also parallel to the longitudinal axis) that is parallel to the longitudinal axis and extends along the wall or surface of the scintillator module. The starting point of the taper may also be close to the second end 109A. Furthermore, since the taper at the second end 109A is not oriented to address unexpected leakage between scintillator modules, each associated with a different sensor 120 or pixel, the length of the second tapered section 1000 may be shorter than the length of the first tapered section 1005. Because the length of the second tapered section 1000 may be shorter than the length of the first tapered section 1005, the angle of taper B with respect to the second tapered section 1000 may be greater than the angle of taper A with respect to the first tapered section 1005.

[0064] The same scintillator module 100C may be tapered on the first end 107 and the second end 109A, but the tapered portion or wall will be offset. For example, as shown in Figure 10, the scintillator module 100C is tapered at the first end (first tapered portion 1005) on a wall or portion facing the boundary or edge of the active region 310. However, since the segments of the segmented optical waveguide 110A are offset relative to the sensor 120 and contact the scintillator module at different pixels (adjacent pixels or nearby pixels), the wall or portion tapered with respect to the second end 109A is a wall or portion that does not face the boundary or edge of the active region 310 (for example, an inner opposing wall or portion).

[0065] Figures 11–15 show different diagrams of each scintillator module manufactured according to an embodiment of the present disclosure having a tapered first end 107. In this case, there is a 4:1 coupling of scintillator modules to optical sensors. Figures 11 and 12 show a scintillator module without an optical waveguide or optical sensor (or reflector). As shown in Figures 11 and 12, the scintillator modules 100 are arranged as a 16 × 16 array (LYSO crystal). Each scintillator module 100 is designed to be approximately 20 mm in the longitudinal axis direction (z-direction). The second end 109 is designed to have a second cross-sectional area of ​​approximately 1.5 mm × approximately 1.5 mm. The scintillator module 100 had approximately this cross-sectional area until the tapering began. The tapering was designed to begin at a position approximately 5 mm away from the first end (scintillator module and optical sensor interface). The first cross-sectional area is a gap G D Designed to be approximately 1.4 × 1.4 mm in size to minimize overlap with 119 and keep the first end 107 within the active region 310. Tapering was performed only on the walls or portions facing the boundary or edge of the active region 310. Scintillator module gap G between adjacent scintillator modules s 117 was approximately 1 mm.

[0066] As shown in Figure 13, the second end 109 is in contact with the segmented optical waveguide 110A. In this case, the segmented optical waveguide was a pseudo-prismatic optical waveguide array (radiation receiving end). The reflector 115 is positioned at the top of the segmented optical waveguide 110A.

[0067] Figure 14 shows the scintillator module 100 before it is attached to the optical sensor. As can be seen in Figure 14, the space between scintillator modules associated with different pixels (sensors) at the first end 107 is the scintillator module gap G S It is greater than 117.

[0068] The optical sensor gap was approximately 0.2 mm. The active area was approximately 3.00 mm x 3.00 mm. The pixel pitch was approximately 3.2 x 3.2 mm.

[0069] Figure 15 shows the scintillator module 100 in contact with the optical sensor array 300. The optical sensor array 300 is electrically coupled to a connector 1500. This connector 1500 is electrically coupled to a processor (not shown in Figure 15). The processor is configured for DOI and TOF analysis. The processor runs one or more programs to determine the DOI and TOF.

[0070] Figures 16 and 17 show different diagrams of scintillator modules manufactured according to an embodiment of the present disclosure, each having a tapered first end 107 and a tapered second end 109A. In this case, there is a 4:1 coupling of the scintillator module to the optical sensor. As shown in Figures 16 and 17, the scintillator module 100C has a first tapered portion 1005 and a second tapered portion 1000. The length of the second tapered portion 1000 in the longitudinal axis direction is shorter than the length of the first tapered portion 1005 in the longitudinal axis direction. Also, as shown in Figures 16 and 17, the tapered wall or portion for the first tapered portion 1005 and the tapered wall or portion for the second tapered portion 1000 are different (shifted). The second cross-sectional area is designed to be approximately 1.35 mm × 1.35 mm. Figures 16 and 17 also show reflectors 115B that cover the outside of the scintillator module 100 to prevent light leakage from corner and edge pixels. For illustrative purposes, the reflector 115B is shown only around a portion (center) of the scintillator module 100 so that the scintillator module 100 is visible. However, in operation, the reflector 115B extends along the entire longitudinal length of the scintillator module (edge ​​and corner modules).

[0071] The tapered first end 107 of the scintillator module 100 described herein improves the correlation between TOF and DOI. A scintillator module array was manufactured as described herein, and the correlation between TOF and DOI was determined. Depth-sighted data (flood histograms) were acquired at 1 mm increments at 19 different depths (1 mm to 19 mm). A 4:1 coupling of scintillator modules and optical sensors was used. A 3 MBq Na-22 point source (1 mm effective diameter) was placed in a lead cylinder with a 1 m diameter pinhole and positioned between the detection device described herein and an untapered reference scintillator array. The reference scintillator array had a 4:1 coupling with SiPM. The scintillator module had dimensions of approximately 1.4 mm × approximately 1.4 mm × approximately 20 mm. The same SiPM was used for both. Two sides were tapered (boundary walls) as described above.

[0072] Barium sulfate

[0073]

number

[0074] The intercrystal spaces were filled using these materials, which acted as diffuse reflectors in the crystal array and optical waveguide. All crystals were thoroughly polished, and the modules were covered with black tape.

[0075] Light leakage at the interface is random, but the light shared within a segmented optical waveguide (pseudo-prism) is deterministic.

[0076] Only matching events between the detection device and the reference according to the embodiments of this disclosure were used for data analysis to eliminate Compton scattering. For example, only events where the highest signal was greater than twice the second highest signal were accepted. 10,000,000 events diffused across all scintillator modules were acquired and used for analysis. Photoelectric peak filtering was performed for each scintillator module using a 15% energy window.

[0077] We examined the correlation between DOI and TOF for each event using three different estimation parameters: one based on energy, and two based on timing.

[0078] Energy-based DOI(w E Using the energy-weighted average method for ), we use the following formula: w E The result was calculated.

[0079]

number

[0080] In the above equation, w E is the energy-weighted DOI parameter, and P m P is the maximum energy absorbed on a single SiPM pixel, and P is the sum of all energies across all pixels.

[0081] Timing-based DOI(w TOF The following two different methods were used to calculate it. w TOF1 = t n1 - t p (2) In the above equation, w TOF1 This is a TOF weighted DOI parameter that uses a single timestamp, and t n1 is the first timestamp from the adjacent pixel to the primary pixel, and t p This is the timestamp from the primary pixel (i.e., the primary timestamp). An adjacent pixel is one of the nearest neighbor pixels coupled to the same optical waveguide segment (the same pseudo-prismatic optical waveguide).

[0082]

number

[0083] In the above equation, w TOF3This is a TOF weighted DOI parameter that uses three timestamps, and t n1 t n2 , and t n3 are the first, second, and third timestamps from adjacent pixels, and t p This is the primary timestamp. Three adjacent pixels are nearest neighbor pixels coupled to the same optical waveguide segment (the same pseudo-prismatic optical waveguide).

[0084] Figure 18 shows a graph illustrating the correlation between depth interaction position and time of flight for two different timestamping methods. The x-axis is the energy-based DOI estimate (w) in arbitrary units. E ) is the result. The y-axis is the timing-based DOI (time of flight). There is a strong correlation between the energy-based estimate and the timing-based estimate (using both timestamps, e.g., 1 and 3). Equations 1 and 3 (w E and w TOF3 The correlation between the judgment values ​​using ) is given by equation 1 and equation 2 (w E and w TOF1 The correlation between judgment values ​​was stronger than that using ). For example, w E and w TOF3 Regarding R 2 = 0.53, and w E and w TOF1 Regarding R 2 The result was 0.31.

[0085] Figures 19A–19C show estimated histograms based on five different depths used: 2mm, 6mm, 10mm, 14mm, and 18mm. 0mm represents the depth in the optical waveguide, and 20mm represents the depth in the optical sensor array interface. In Figure 19A, the DOI was calculated for each event using Equation 1 (w E The frequency at which each ratio value was calculated is the count. Next, a histogram was plotted. Then, the ratio values ​​were converted to depths in millimeters. This conversion may be determined based on the following formula. DOI = m * w + q (4) In the above equation, m is the gradient between DOI and w, and q is the intercept, ensuring that DOI always starts from 0. w is w E (When plotting using formula 1), w TOF1 (When plotting using formula 2), w TOF3 (When plotting using Equation 3) it is one of the following. This equation is based on a standard linear regression model, where "m" and "q" in Equation 4 are w E , w TOF1 , and w TOF3 They may be different when used to determine the DOI.

[0086] The ratio ranges from 0 to 1. 0 may be correlated to a depth of 20 mm, and 1 may be correlated to a depth of 0 mm. The estimated DOI for each ground truth is shown in the inset of Figure 19A, for example, 2.5 mm for 2 mm, 2.1 mm for 6 mm, 2 mm for 10 mm, 2.1 mm for 14 mm, and 2.4 mm for 18 mm (rounded to one decimal place).

[0087] The estimated DOI resolution for tapered scintillator modules was 2.22 mm FWHM using the energy-weighted method (Figure 19A). The estimated DOI resolution was determined by averaging the estimated DOI for each ground truth. The DOI resolution for a reference scintillator array, e.g., a non-tapered scintillator module, was 2.5 mm FWHM.

[0088] In Figure 19B, for each event, formula 2(w TOF1DOI was calculated using ). The frequency with which each ratio value was calculated is the count. Next, a histogram was plotted. Next, the ratio values ​​were converted to depths in mm. This conversion may be determined based on Equation 4. The estimated DOI for each ground truth is shown in the inset of Figure 19B, for example, 6.1 mm for 2 mm, 9.4 mm for 6 mm, 9 mm for 10 mm, 6.6 mm for 14 mm, and 5.6 mm for 18 mm (rounded to one decimal place). TOF1 The estimated DOI resolution for a tapered scintillator module using [specific technology / method] was 7.38 mm. The estimated DOI resolution was determined by averaging the estimated DOI for each ground truth.

[0089] In Figure 19C, for each event, formula 3(w TOF3 DOI was calculated using ). The frequency with which each ratio value was calculated is the count. Next, a histogram was plotted. Next, the ratio values ​​were converted to depths in mm. This conversion may be determined based on Equation 4. The estimated DOI for each ground truth is shown in the inset of Figure 19B, for example, 5.9 mm for 2 mm, 5.8 mm for 6 mm, 5.5 mm for 10 mm, 5.1 mm for 14 mm, and 4.6 mm for 18 mm (rounded to one decimal place). TOF3 The estimated DOI resolution for a tapered scintillator module using [specific technology / method] was 5.38 mm. The estimated DOI resolution was determined by averaging the estimated DOI for each ground truth.

[0090] The coefficients in Equation 4 may differ for each of Figures 19A to 19C.

[0091] In this specification and in the claims, the term “approximately” indicates that the listed values ​​may be changed to some extent, provided that the change does not result in a non-conformity of the process or device. For example, for some elements, the term “approximately” may refer to a variation of ±0.1%, and for other elements, the term “approximately” may refer to a variation of ±1% or ±10%, or any point within that range. For example, when the term “approximately” is used in measurements in millimeters, it may include + / 0.1, 0.2, 0.3, etc., and the difference between the listed numbers may be greater the larger the listed number. For example, approximately 1.5 may include 1.2 to 1.8, and approximately 20 may include 19.0 to 21.0.

[0092] As used herein, the terms “substantially” or “substantial” are equally applicable when used in a negative sense to refer to the absence or near absence of an action, characteristic, feature, state, structure, item, or result. For example, a “substantially” flat surface is either perfectly flat or nearly flat to the same extent as a perfectly flat surface. When referring to shape or size, “substantially” may be used to describe a manufacture in which it may be difficult to manufacture a perfect shape or a perfect size, such as a circle.

[0093] As used herein, terms such as "a," "an," and "the" are not intended to refer only to singular entities, but to include general classes for which specific examples may be used as illustrations. As used herein, terms defined in the singular form are intended to include terms defined in the plural form, and vice versa.

[0094] In this specification, references to “one aspect,” “a certain aspect,” “several aspects,” or “aspects” indicate that the aspects described may include certain features or characteristics, but not all aspects necessarily include those specific features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same aspect. Moreover, when describing certain features, structures, or characteristics in relation to an aspect, it is assumed that the effect on such features, structures, or characteristics in relation to other aspects, whether explicitly stated or not, is within the knowledge of those skilled in the art. Hereafter, for the sake of explanation, the terms “top,” “bottom,” “right,” “left,” “vertical,” “horizontal,” “top,” and “bottom,” and their derivatives, refer to the device relative to the floor and / or the orientation in the figures.

[0095] Any reference to a numerical range in this specification explicitly includes each number (including decimals and integers) that is encompassed by that range. For example, a reference to the range “at least 50” or “at least about 50” in this specification includes integers such as 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, and 60, and decimals such as 50.1, 50.2, 50.3, 50.4, 50.5, 50.6, 50.7, 50.8, and 50.9. As a further example, a reference to the range “less than 50” or “about less than 50” in this specification includes integers such as 49, 48, 47, 46, 45, 44, 43, 42, 41, and 40, and decimals such as 49.9, 49.8, 49.7, 49.6, 49.5, 49.4, 49.3, 49.2, 49.1, and 49.0.

[0096] As used herein, the term “processor” may include a single-core processor, a multi-core processor, multiple processors located within a single device, or multiple processors wired or wirelessly connected to one another and distributed across a network of devices, the internet, or the cloud. Therefore, as used herein, a function, feature, or instruction executed or configured to be executed by a “processor” may include the execution of a function, feature, or instruction by a single-core processor, the collective or collaborative execution of a function, feature, or instruction by multiple cores of a multi-core processor, or the collective or collaborative execution of a function, feature, or instruction by multiple processors, and each processor or core is not required to execute every function, feature, or instruction individually. For example, a single FPGA or multiple FPGAs may be used to implement the functions, features, or instructions described herein. For example, multiple processors may enable load balancing. In a further example, a server (also called a remote or cloud) processor may implement some or all of the functions on behalf of a client processor.

[0097] As used herein, the terms “processor” or “controller” may be replaced with the term “circuit,” such as ASIC. The term “processor” may refer to, be part of, or include processor hardware (shared, dedicated, or group) that executes code, and may refer to, be part of, or include memory hardware (shared, dedicated, or group) that stores code executed by the processor, or include memory hardware.

[0098] Furthermore, in some aspects of this disclosure, a non-temporary computer-readable storage medium is provided which electronically readable control information is stored and which is configured to perform the functions described herein when used in a processor.

[0099] Furthermore, any of the above methods may be embodied in the form of a program. The program may be stored on a non-temporary computer-readable medium and, when executed on a computer device (a device including a processor), is adapted to perform any of the above methods. Thus, a non-temporary tangible computer-readable medium is adapted to store information and to interact with a data processing function or computer device to execute any of the above embodiments of a program and / or perform any of the above embodiments of a method.

[0100] Computer-readable media or storage media may be internal media installed within the body of a computer device or a removable medium and configured to be separable from the body of the computer device. As used herein, the term computer-readable media does not include transient electrical or electromagnetic signals propagating within a medium (such as on a carrier wave), and therefore, the term computer-readable media is considered tangible and non-transient. Non-limiting examples of non-transient computer-readable media include, but are not limited to, rewritable non-volatile memory devices (e.g., flash memory devices, erasable programmable read-only memory devices, or mask read-only memory devices), volatile memory devices (e.g., static random-access memory devices or dynamic random-access memory devices), magnetic storage media (e.g., analog or digital magnetic tape or hard disk drives), and optical storage media (e.g., CDs, DVDs, or Blu-ray® Discs). Examples of media containing internal rewritable non-volatile memory include, but are not limited to, memory cards, and media containing internal ROM, including, but are not limited to, ROM cassettes. Furthermore, various information about the stored image, such as characteristic information, may be stored in any other form or provided by other means.

[0101] The term "memory hardware" is a subset of the term "computer-readable media."

[0102] The embodiments and examples described above in this disclosure are illustrative and not restrictive, and are not intended to represent all embodiments or examples of this disclosure. While the fundamental novel features of this disclosure applicable to various specific embodiments of this disclosure have been illustrated, described and pointed out, it will be understood that various omissions, substitutions, and modifications in the form and details of the illustrated devices and in the operation of the devices can be made by those skilled in the art without departing from the spirit of this disclosure. It is expressly intended that all combinations of elements and / or method steps that perform substantially the same function substantially in the same way and achieve the same results are within the scope of this disclosure. Furthermore, it will be recognized that any structures and / or elements and / or method steps illustrated and / or described in relation to any disclosed form or embodiment of this disclosure may be incorporated into any other disclosed or described or suggested form or embodiment as a general matter of design choice. Furthermore, various modifications and variations can be made without departing from the spirit or scope of this disclosure as set forth in the following claims, or from equivalents recognized by law. [Explanation of symbols]

[0103] 1. Detection device 1A Detection device 1B Detection device 100 Scintillator Modules 100A Scintillator Module 100B Scintillator Module 100C Scintillator Module 105 Tapered section 105A Tapered section 105B Tapered section 107 First end 107A First end 107B First end 109 Second end 109A Second end 110 Optical waveguide 110A Segmented Optical Waveguide 115 Reflector 115A Reflector 115B Reflector 117 Sensor gap G D 119 Module Gap G s 119A Module Gap G S 119B Module Gap G S 120 Optical Sensors 121 Overlapping Regions 300 active area, sensor array 305 Boundary Wall 310 Active Area 315 Non-tapered wall 400 First cross-sectional area 405 Second cross-sectional area 410 Space 415 Group 1000 Second tapered section 1005 First tapered section 1500 connector

Claims

1. A particle detection device, An array of optical sensors arranged as a two-dimensional array, wherein there is a first gap between adjacent optical sensors, and each optical sensor corresponds to a pixel and has an active region, and the array of optical sensors, A plurality of scintillator modules, wherein at least one scintillator module corresponds to an optical sensor in the array of optical sensors, each scintillator module has a first end and a second end that contact the corresponding optical sensor, there is a second gap between adjacent scintillator modules, the second gap is the minimum gap between adjacent scintillator modules, and the scintillator module adjacent to the boundary of the active region of the corresponding optical sensor has a tapered portion at the first end, so that when viewed along the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region, and the first cross-sectional region is perpendicular to the longitudinal axis, Each scintillator module comprises a segmented optical waveguide that contacts the second end of the scintillator module, The second end of a particular scintillator module has a second tapered portion, A particle detection device in which the second gap is smaller than the first gap.

2. The particle detection device according to claim 1, wherein the second cross-sectional region above the tapered portion and below the second tapered portion is larger than the first cross-sectional region, and the second cross-sectional region is perpendicular to the longitudinal axis.

3. The particle detection device according to claim 2, wherein, when viewed along the direction of the longitudinal axis, at least a portion of the second cross-sectional area at the second end overlaps with the first gap.

4. The particle detection device according to any one of claims 1 to 3, wherein the first cross-sectional region is substantially circular in shape.

5. The particle detection device according to any one of claims 1 to 3, wherein the at least one scintillator module is a single scintillator module, thereby arranging a one-to-one correspondence between the scintillator module and the optical sensor, the first cross-sectional area of ​​each scintillator module being rectangular, and all four sides at the first end being tapered.

6. The particle detection device according to any one of claims 1 to 3, wherein the at least one scintillator module comprises four scintillator modules, thereby arranging the scintillator modules to the optical sensors in a 4:1 ratio, the first cross-sectional region of each scintillator module is defined by a plurality of sides, and at least two sides of the scintillator module facing each boundary of the active region are tapered at the first end.

7. The particle detection device according to claim 6, wherein only the sides of the scintillator module facing each boundary of the active region are tapered at the first end.

8. The particle detection device according to any one of claims 1 to 7, wherein the tapered portion has a tapered length in a direction parallel to the longitudinal axis, and the tapered length is shorter than one-third of the length from the first end to the second end in the direction parallel to the longitudinal axis.

9. The particle detection device according to claim 8, wherein the taper length is substantially the same for each scintillator module having the tapered portion.

10. The particle detection device according to claim 8 or 9, wherein the length from the first end to the second end is 20 mm, and the taper length is 5 mm.

11. The particle detection device according to claim 2, wherein the second cross-sectional area is 1.5 mm × 1.5 mm and the first cross-sectional area is 1.4 mm × 1.4 mm.

12. The particle detection device according to claim 11, wherein the active area is 3.0 mm × 3.0 mm.

13. The particle detection device according to any one of claims 1 to 12, wherein each segment is a pseudoprism, and each pseudoprism is configured to change the direction of emission of radiation particles between the second ends of the scintillator module.

14. The particle detection device according to any one of claims 1 to 13, further comprising a reflector positioned on the optical waveguide and between segments of the optical waveguide.

15. The particle detection device according to any one of claims 1 to 14, further comprising a reflector positioned between each scintillator module, including in the space between the tapered portion and another scintillator module.

16. The particle detection device according to any one of claims 1 to 15, wherein the second tapered portion has a tapered length in the longitudinal direction, and the tapered length is shorter than the tapered length of the tapered portion at the first end in the longitudinal direction.

17. The particle detection device according to any one of claims 1 to 16, wherein the segment of the optical waveguide is offset from the optical sensor, so that the first scintillator module in contact with the first optical sensor and the second scintillator module in contact with the second optical sensor are in contact with the same segment.

18. The particle detection device according to claim 17, wherein the side surface of the scintillator module tapered at the second end is different from the side surface of the scintillator module tapered at the first end.

19. Multiple scintillator modules correspond to each optical sensor in the optical sensor array, The particle detection device according to claim 1, wherein at least a subset of the plurality of scintillator modules corresponding to each optical sensor has the tapered portion at the first end, and the position of the tapered portion and which of the plurality of scintillator modules is tapered depends on the relative positions of the scintillator modules within the active region and the respective boundaries of the active region.

20. The particle detection device according to claim 19, wherein the scintillator module located at the corner of the active region may have at least two tapered sides at the first end so that, when viewed along the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region, and the first cross-sectional region is perpendicular to the longitudinal axis.

21. The particle detection device according to claim 20, wherein only the two sides of the scintillator module located at the corner of the active region are tapered at the first end.

22. The particle detection device according to claim 21, wherein the scintillator module located between other scintillator modules that are positioned and aligned at the corners of the active region has only one side tapered at the first end, so that when viewed along the direction of the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region, and the one side faces the boundary of the active region.

23. The particle detection device according to claim 22, wherein the scintillator module having another scintillator module located between the scintillator module and the boundary of the active region does not have the tapered portion at the first end.

24. A particle detection device, An array of optical sensors arranged as a two-dimensional array, wherein there is a first gap between adjacent optical sensors, and each optical sensor corresponds to a pixel and has an active region, and the array of optical sensors, A plurality of scintillator modules, wherein at least one scintillator module corresponds to an optical sensor in the array of optical sensors, each scintillator module has a first end and a second end that contact the corresponding optical sensor, there is a second gap between adjacent scintillator modules, the second gap is the minimum gap between adjacent scintillator modules, and the scintillator module adjacent to the boundary of the active region of the corresponding optical sensor has a tapered portion at the first end, so that when viewed along the longitudinal axis, the first cross-sectional region at the first end overlaps with the active region, and the first cross-sectional region is perpendicular to the longitudinal axis, The second gap is smaller than the first gap. The at least one scintillator module comprises four scintillator modules, thereby arranging the scintillator modules and the optical sensors in a 4:1 ratio, the first cross-sectional region of each scintillator module being defined by a plurality of sides, and at least two sides of the scintillator module facing each boundary of the active region being tapered at the first end. A particle detection device in which only the sides of the scintillator module facing each boundary of the active region are tapered at the first end.

Images