Prismatoid light guide

Abstract

To provide a device for detecting subatomic particles and a method of manufacturing the same.SOLUTION: A device includes a plurality of scintillators, a detector provided on a first edge part of the plurality of scintillators, and a prismatoid provided on a second edge part of the plurality of scintillators. The prismatoid reroutes light between adjacent scintillators of the plurality of scintillators.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] (Related Applications) This application claims priority to U.S. Provisional Patent Applications Nos. 62 / 789,559 and 62 / 957,991, filed in the U.S. Patent and Trademark Office on January 8, 2019 and January 7, 2020, respectively, the entire contents of each of which are incorporated herein by reference.

[0002] (government aid) This invention was made with government support awarded by the National Institutes of Health under Grant No. EB024849. The United States Government has certain rights in this invention.

[0003] (Technical field) The present invention relates generally to the field of radiological imaging, and specifically to positron emission tomography (PET). [Background technology]

[0004] PET is a nuclear medicine imaging modality that produces three-dimensional (3D) images for observing functional processes in living organisms. PET is commonly used in clinical oncology to detect cancer and for clinical diagnosis of heart and / or brain disorders. After being introduced into an organism, positron-emitting radionuclides decay, emitting two diametrically opposed photons at each annihilation. Time-of-flight (TOF) measurements can be used to measure the time it takes for an electromagnetic wave to propagate a distance through a medium. TOF PET systems detect photons and use the TOF information to determine whether two recorded photons are in a state of time coherence, i.e., belong to an annihilation event at the same location. TOF PET uses the difference in arrival times to localize each annihilation event. In the absence of TOF localization data, computationally expensive iterative reconstruction algorithms are used to estimate the 3D event distribution that gives the best match with the measured projection data. Modern PET readouts are performed with silicon photomultipliers (SiPMs) due to their speed and magnetic resonance compatibility.

[0005] For PET scintillators, high position of interaction (DOI) resolution is required to reduce parallax and the resulting spatial blur, which is especially noticeable in detection systems with small ring diameters such as single organ inserters. Traditionally, DOI readout is performed by double-sided readout using two readout arrays per scintillator array. However, double-sided readout requires twice the electronics compared to a typical PET system. Recent research has therefore focused on developing single-sided readout techniques that require only one scintillator and one readout array. Although 1:1 coupling can also be used, multiple scintillator crystals are typically combined into a single readout pixel to reduce system costs.

[0006] The latest DOI technique uses a substantially flat reflective light guide on top of the scintillator array to reroute the light to other readout pixels. In doing so, DOI information can be obtained by detecting the fraction of the maximum light absorbed on a single SiPM pixel for a single gamma ray interaction event and this detection fraction relative to the total light absorbed across all pixels of the array. Only two different readout pixels are needed to make this measurement. However, it is useful to have more pixels to improve the DOI resolution.

[0007] Conventional light guide geometries use flat, uniformly reflective materials that primarily guide light back into the original scintillation crystal where gamma ray absorption occurred, rather than rerouting the light into another crystal to read out the pixel. This results in suboptimal DOI resolution because most of the light is not shared with other pixels needed to make the DOI measurement, thus invalidating the single-sided DOI readout. Current single-sided DOI readout using high aspect ratio scintillators (~15-20 mm thick) and uniform light guides can only achieve ~5 mm full width at half maximum (FWHM) DOI resolution. In contrast, double-sided readout can achieve DOI resolution on the order of 1 mm FWHM, leaving considerable room for improvement of single-sided techniques before they are feasible for practical use. Conventional systems and methods are unable to implement impactful light sharing techniques in PET detector systems.

[0008] Conventionally, Anger Logic schemes are used to improve the overall detector system by finely localizing the gamma ray interaction down to the crystal level through centroiding. Due to poor light sharing in conventional uniform light guides, Anger Logic localization at the periphery of the detector array is significantly poorer than that of the central crystals and detectors since the peripheral crystals have fewer crystals and pixels to share. Summary of the Invention [Problem to be solved by the invention]

[0009] To overcome the shortcomings of conventional systems, systems and methods are presented herein for improving light sharing between scintillator crystals in a PET detector system. The present disclosure overcomes the shortcomings of conventional DOI readout systems and methods, and provides improved DOI resolution and more uniform Anger Logic localization performance across the detector array. [Means for solving the problem]

[0010] Accordingly, aspects of the present invention address the problems and shortcomings discussed above and provide the advantages described below.An aspect of the present invention provides a device for detecting sub-atomic particles, the device comprising a plurality of scintillators, at least one detector disposed on a first end of the scintillators, and a prismatoid disposed on a second end of the scintillators, the prismatoid configured to redirect light between a first pair of adjacent scintillators of the plurality of scintillators.

[0011] One aspect of the present invention provides a prismatoid comprising a reflective surface configured to redirect the propagation of at least one photon emitted from at least one of a first pair of scintillators adjacent to the reflective surface, such that the propagation of at least one photon is redirected from at least one of a first pair of scintillators towards another of the first pair of scintillators.

[0012] A further aspect of the present disclosure provides a system for non-invasive medical imaging including at least one prismatoid, at least one detector, and a scintillator array, where the at least one prismatoid redirects light between adjacent scintillators of the scintillator array, the at least one detector is disposed on an end of the scintillator array opposite the at least one prismatoid, and the prismatoid is substantially shaped as at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one truncated tower, at least one rectangular solid, at least one wedge, at least one pyramid, at least one truncated pyramid, and at least one partial sphere.

[0013] These and other aspects, features, and advantages of certain embodiments of the present invention will become clearly apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of a prismatoid light guide according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a perspective view of a prismatoid light guide according to an embodiment of the present disclosure. [Diagram 3] FIG. 2 is a cutaway side cross-sectional view of a prismatoid light guide positioned over a scintillator array according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a top view of a prismatoid light guide according to an embodiment of the present disclosure. [Figure 5a] FIG. 1 is a perspective view of a prismatoid according to one of several embodiments of the present disclosure. [Figure 5b] FIG. 1 is a perspective view of a prismatoid according to one of several embodiments of the present disclosure. [Figure 5c] FIG. 1 is a perspective view of a prismatoid according to one of several embodiments of the present disclosure. [Figure 6] FIG. 2 is a perspective view of a second prismatoid according to an embodiment of the present disclosure. [Figure 7a] FIG. 1 is a perspective view of a prismatoid according to one of several embodiments of the present disclosure. [Figure 7b] FIG. 1 is a perspective view of a prismatoid according to one of several embodiments of the present disclosure. [Figure 8a] FIG. 2 illustrates a prismatoid light guide array separated from a scintillator array according to an embodiment of the present disclosure. [Figure 8b] 1 illustrates a scintillator array separated from a prismatoid light guide array according to an embodiment of the present disclosure. [Figure 9a] FIG. 1 illustrates light sharing in a conventional planar light guide. [Figure 9b] FIG. 1 illustrates light sharing of prismatoids according to an embodiment of the present disclosure. [Figure 10] FIG. 1 presents an illuminance map simulation for a conventional planar light guide. [Figure 11]FIG. 13 presents an illumination map simulation according to an embodiment of the present disclosure. [Figure 12] 1 is a graph of percentage light sharing across multiple adjacent silicon photomultiplier detectors comparing the percentage light sharing of conventional flat glass to the percentage light sharing of a prismatoid light guide according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The following detailed description of certain embodiments of the present invention will be given with reference to the accompanying drawings. In describing the present invention, descriptions of relevant functions or structures known in the art will be omitted for the purpose of clarity, so as to avoid obscuring the present invention with unnecessary details.

[0016] FIG 1 is a perspective view of a prismatoid light guide according to an embodiment of the present disclosure. The prismatoid light guide 100 in FIG 1 is positioned on a scintillator array 200, with a detector 300 positioned on the opposite side of the prismatoid light guide 100. As illustrated in FIG 1, the prismatoid light guide 100 includes a plurality of first prismatoids 410, which may be triangular in shape and are surrounded by second prismatoids 420 and corner prismatoids, the details of which are presented herein. The prismatoid light guide 100 may be fixedly or removably disposed on the scintillator array 120.

[0017] Figure 2 is a perspective view of the prismatoid light guide 100. As illustrated in Figure 2, the plurality of first prismatoids 410 can be substantially pyramidal. The first prismatoid 410, the second prismatoid 420, and the third prismatoid can be substantially shaped as at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one truncated tower, at least one rectangular solid, at least one wedge, at least one pyramid, at least one truncated pyramid, and at least one partial sphere.

[0018] FIG. 3 is a cutaway side cross-sectional view illustrating the geometry of a central portion of a prismatoid light guide 100 positioned on a scintillator array 200 according to an embodiment of the present disclosure. As illustrated in FIG. 3, the prismatoid can be substantially shaped as a pyramid having three faces 120a, 120b, 120c. The prismatoid light guide 100 can be positioned on or adjacent to a first end 211d, i.e., a first end face, of the scintillator array 200. The prismatoid light guide 100 acts as a reflector that enhances light sharing to enable at least a 4:1 coupling between the scintillators 211, 212, 213, 214. The prismatoid light guide 100 includes at least one reflective surface, e.g., the inner surface of faces 120a, 120b, that redirects the propagation of at least one subatomic particle, e.g., photon, emitted from at least one scintillator of the first pair of adjacent scintillators. The inner surfaces of the faces 120a, 120b may be coated with barium sulfate, epoxy, or provided with enhanced specular reflectors (ESR) for improved reflectivity along the sides. Each scintillator of the scintillator pair may be a scintillator crystal configured to convert high energy x-rays, gamma rays, and similar high energy particles into light and / or photons as known in the art. The change in propagation direction is due to at least one scintillator emitting at least one subatomic particle toward at least one other scintillator of the at least four adjacent scintillators. The provided coupling improves detection by the silicon photomultiplier (SiPM) pixels 380a, 380b, 380c...380i of the detector 300 positioned at the second end 211b. The SiPM pixels 380a...380i of the detector 300 communicate with at least one processor that controls the display or other output of at least one photon detected by the detector 300 to enable high resolution single-sided readout of location of interaction (DOI) readout in a positron emission tomography (PET) detector.

[0019] Each scintillator 211, 212, 213, 214 may include a first inner surface 211a, 212a and a second inner surface 211c, 212c. The second inner surface 211c, 212c may be substantially parallel to the respective first inner surface 211a, 212a, and the first inner surface 211a, 212a and the second inner surface 211c, 212c extend substantially from the first end 211d to the second end 211b, thereby providing an internal light guide 211g, 212g between each respective first surface 211a, 212a and second surface 211c, 212c configured to reflect light between each other to transmit substantially all of the light from the respective prismatic 120 of the prismatic light guide 100 to the respective detector 300. The internal light guide reflects substantially all of the light propagating from each prismatoid 120 in each scintillator 211, 212, 213, 214 to each detector 130. As illustrated in FIG. 9B, the prismatoid 120 redirects light from the light guide of a first scintillator to the light guide of an adjacent scintillator, with light sharing being self-contained within the scintillation crystal coupled to the prismatoid 120.

[0020] The prismatoid 120 provides a stabilized light guide geometry to the first end 211d of the scintillator array 100. The prismatoid light guide 100 reflects light without functioning as a high energy photon detector. As illustrated in Figures 3, 4, 8a, and 8b, the scintillators 211, 212, 213, and 214 can be combined in a 4:1 ratio for photon detection by a shared SiPM pixel, e.g., SiPM pixel 380a and SiPM pixel 380b are shared by the scintillators 211, 212, 213, and 214 via the prismatoid 120 of the prismatoid light guide 100.

[0021] To enable differential single-sided readout for DOI performance, at least two SiPM pixels 380a, 380b of the detector 300 are coupled to a respective prismatoid 120 via the scintillator crystals 211, 212, 213, 214. Figures 3, 4, 8a, and 8b illustrate a scintillator to readout coupling ratio of 1:4. The prismatoid 120 can be coupled to one end of the crystals 211, 212, 213, 214 and the SiPM pixels 380a, 380b can be coupled to the opposite end. Other bond ratios can be used in various prismatoid geometries, with the prismatoid 120 being substantially shaped as at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one truncated tower, at least one rectangular prism, at least one wedge, at least one pyramid, at least one truncated pyramid, and at least one partial sphere.

[0022] 4 is a top view of a prismatoid light guide 100 with various prismatoid geometric locations to introduce more uniform directional light sharing along the edges of the scintillator array 200. This prismatoid array geometry allows for improved coupling and controlled light sharing of each non-peripheral prismatoid to the four SiPM pixels of the detector 300. FIG 4 illustrates scintillators 211, 212, 213, 214 sharing a common detector 300. Scintillators 211 and 212 may also be provided as a first pair of adjacent scintillators, and scintillators 213, 214 may be provided as a second pair of adjacent scintillators, with a first scintillator of the first pair of adjacent scintillators adjacent to a first scintillator of the second pair of adjacent scintillators, and the first scintillator of the first pair of adjacent scintillators sharing a first detector of the plurality of detectors with the first scintillator of the second pair of adjacent scintillators. The second scintillator of the first pair of adjacent scintillators may be adjacent to a second scintillator of the second pair of adjacent scintillators, and the second scintillator of the first pair of adjacent scintillators may share a second detector of the plurality of detectors with the second scintillator of the second pair of adjacent scintillators. Thus, the prismatoid can redirect light from a first scintillator of a first pair of adjacent scintillators to at least one of a second scintillator of the first pair of adjacent scintillators, a first scintillator of a second pair of adjacent scintillators, and a second scintillator of a second pair of adjacent scintillators.

[0023] The controlled light sharing of the present disclosure increases system-level count rates. In contrast, in a uniform light guide, each scintillation event requires readout from all SiPM pixels to calculate DOI and perform centroiding, since light is expected to be shared across all scintillators. In contrast, the prismatoid light guide of the present invention allows for precise identification of which scintillator columns will share light with each other. Scintillators only share light with columns that are coupled to the same prismatoid. As illustrated, each non-peripheral prismatoid is coupled to at least four scintillators belonging to at least two to four SiPM pixels, depending on the detector array geometry. As a result, readout is only required for a small subset of pixels at a time for each scintillation event, allowing for simultaneous readout in other parts of the detector array, thereby increasing system-level count rates when compared to the count rates of detector systems using conventional uniform light guides.

[0024] 5a-5c are perspective views of prismatoids according to embodiments of the present disclosure. Fig. 5a is a perspective view of a first prismatoid 410 having a substantially pyramidal shape. Fig. 5b is a perspective view of a first prismatoid 410 having a shape combining a substantially pyramidal shape with a substantially rectangular parallelepiped shape. Fig. 5c is a perspective view of a first prismatoid 410 having a substantially triangular shape.

[0025] 6 is a perspective view of the second prismatoid 420. The second prismatoid 420 has a substantially triangular shape.

[0026] 7a and 7b are perspective views of a prismatoid 430. FIG. 7a illustrates a corner prismatoid including substantially rectangular parallelepiped shapes 435, 436 affixed thereto substantially triangular shapes 432, 433, respectively. The rectangular parallelepiped shapes 435, 436 may also be integrally formed on the triangular shapes 432, 433. FIG. 7b illustrates a corner prismatoid including substantially rectangular parallelepiped shapes 430a, 430b affixed thereto substantially triangular shapes 430c, 430d, respectively. The arrangement of the first prismatoid 410, the third prismatoid 420, and the third prismatoid 430 is presented in FIGS. 2-4.

[0027] Light is purposely directed to other pixels, resulting in high uniformity of the AngerLogic centroiding resolution across the detector array. In contrast, conventional uniform light guides do not specifically couple or purposely direct light to specific other SiPM pixels. Conventional uniform light guides also introduce edge effects where the centroiding resolution falls off sharply along the edges of the scintillator array. In contrast, the configuration of the first prismatoid 410, second prismatoid 420, and third prismatoid 430 is completely symmetric between the scintillators with respect to light sharing, eliminating the edge effects in conventional systems. See Figures 2-4.

[0028] FIG. 8a illustrates a prismatoid light guide separated from a scintillator array according to certain embodiments of the present disclosure. FIG. 8b illustrates a scintillator array separated from a prismatoid light guide array according to certain embodiments of the present disclosure. Assembly of the prismatoid light guide array 100 of FIG. 8a onto the scintillator array 200 of FIG. 8b provides a scintillator to prismatoid ratio of 4:1. The prismatoid light guide array 100 and the scintillator array 200 can also be provided integrally.

[0029] FIG. 9(a) illustrates light sharing of a conventional planar light guide. FIG. 9(b) illustrates light sharing of a prismatoid according to an embodiment of the present disclosure. FIG. 9(a) and FIG. 9(b) are obtained by Monte Carlo simulation. FIG. 9A and FIG. 9B present flood histograms in the upper part and 1-D histograms of x-direction localization of gamma ray interactions in the lower part, which represents the quality of crystal discrimination. FIG. 9A illustrates non-uniform scintillator row discrimination due to edge and corner effects by a uniform glass light guide using Anger Logic centroiding. FIG. 9b illustrates the elimination of edge and corner effects, which improves the light sharing pattern, thereby enabling uniform scintillator row discrimination across the entire detector array, according to an embodiment of the present disclosure.

[0030] A comparison of the ray trajectories in Figure 9(a) with those in Figure 9(b) illustrates the improved light sharing with adjacent scintillator columns made possible by the prismatoid light guide 100. As shown in Figure 9(b), the prismatoid redirects the light into adjacent scintillators and SiPM pixels, thereby enabling more accurate DOI readout due to the improved light sharing between adjacent scintillators.

[0031] Figure 10 presents an illuminance map simulation for a conventional planar light guide. Figure 11 presents an illuminance map simulation according to an embodiment of the present disclosure. The illuminance maps in Figures 10 and 11 are heat maps of photon flux on each SiPM pixel.

[0032] As shown in the conventional planar uniform light guide of Figure 10, most of the light is incident on the lower right corner of the pixel corresponding to the scintillator where the gamma ray interaction occurred. However, with a DOI readout, most of the light would ideally be shared with adjacent pixels to provide more information about where exactly in the scintillator the interaction occurred.

[0033] As shown in FIG. 11, by using the same scintillator as in FIG. 10 but replacing the planar uniform light guide with a prismatoid light guide 100, light sharing for gamma ray interaction imaging with adjacent SiPM pixels as well as with SiPM pixels diagonally from the original readout pixel is significantly improved.

[0034] 12 is a graph of percent light sharing over adjacent SiPMs, comparing the percentage light sharing of conventional flat glass with that of a prismatoid light guide. As illustrated in FIG. 12, the prismatoid light guide 100 allows for a significant improvement in light sharing for all interaction locations, which increases as a function of interaction location, illustrating improved DOI localization accuracy that allows for improved DOI resolution and spatial resolution of the PET detector system.

[0035] A fabrication method is presented that includes attaching a prismatoid light guide onto one end of a scintillator, which may be prepared as a block of scintillator crystal, and attaching a detector module to the opposite end of the scintillator. The prismatoids 120 may be deposited by sputtering onto one end of the scintillator array. The prismatoids may also be removably attached to one end of the scintillator. The scintillator may be polished and subsequently roughened along its sides to introduce roughness and improve DOI resolution by producing differential light sharing along the sides as a function of gamma ray interaction position.

[0036] Although the present invention has been illustrated and described with respect to specific embodiments, it should be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and equivalents thereof. Any claim statements set forth below should not be construed as means-plus-function elements without the explicit use of "means for" or "steps for." [Explanation of symbols]

[0037] 100 Prismatoid Lightpipe 200 Scintillator Array 300 Detectors 410 First Prismatoid 420 Second Prismatoid

Claims

1. A device for detecting subatomic particles, The first scintillator and, The second scintillator, The third scintillator, The fourth scintillator, A detector provided on the first end of the first scintillator, A pair of corner scintillators including a fifth scintillator and a sixth scintillator, The invention comprises a prismatoid provided on the second end of each of the first, second, third, and fourth scintillators, The prismatoid is configured to redirect light between adjacent scintillators forming a first pair among a plurality of scintillators, and the first pair of adjacent scintillators includes the first scintillator and the second scintillator. Each of the fifth and sixth scintillators includes a rectangular parallelepiped shape with a triangular shape attached to the first portion. The device is characterized in that the sides of the rectangular parallelepiped shapes included in the fifth scintillator and the sixth scintillator are adjacent to each other between the triangular shapes, forming a rectangular parallelepiped portion to which the triangular shapes are not attached, and forming the respective corners of the pair of corner scintillators between the triangular shapes.

2. The device according to claim 1, wherein the prismatoid comprises at least one reflective surface for diverting the propagation path of at least one subatomic particle emitted from at least one of the first scintillator or the second scintillator.

3. The first scintillator is an emission scintillator, The device according to claim 2, wherein the propagation of the at least one subatomic particle is rerouted from the first scintillator toward the second scintillator.

4. The device according to claim 1, wherein the prismatoid is substantially formed as at least one of at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one pyramidal tower, at least one cuboid, at least one wedge, at least one pyramid, at least one truncated pyramid, or at least one subsphere.

5. It comprises a second pair of adjacent scintillators, including a third scintillator and a fourth scintillator. The first scintillator of the first pair of adjacent scintillators is adjacent to the third scintillator of the second pair of adjacent scintillators, The device according to claim 1, wherein the first scintillator shares the first detector of the at least one detector with the third scintillator.

6. The second scintillator of the first pair of adjacent scintillators is adjacent to the fourth scintillator of the second pair of adjacent scintillators, The device according to claim 5, wherein the second scintillator shares the second detector of the at least one detector with the fourth scintillator.

7. The device according to claim 6, wherein the prismatoid is configured to redirect light from the first scintillator of the first pair of adjacent scintillators to at least one of the second scintillator of the first pair of adjacent scintillators, the third scintillator of the second pair of adjacent scintillators, or the fourth scintillator of the second pair of adjacent scintillators.

8. Each of the first scintillator and the second scintillator is, The first inner self, A second inner surface substantially parallel to the first inner surface, The device according to claim 1, comprising:

9. The device according to claim 8, wherein the first inner surface and the second inner surface of the first scintillator or the second scintillator are configured to reflect light between their inner surfaces in order to transmit substantially all of the light from the prismatoid to the at least one detector.

10. The device according to claim 1, wherein the at least one detector comprises at least one pixelation sensor.

11. The device according to claim 10, further comprising at least one processor configured to perform positron emission tomography (PET) by communicating with the at least one pixelation sensor to detect at least one photon.

12. It is a prismatoid, A transparent surface adjacent to a first pair of adjacent scintillators including a first scintillator and a second scintillator, a second pair of adjacent scintillators including a third scintillator and a fourth scintillator, and at least one pair of corner scintillators including a fifth scintillator and a sixth scintillator, A reflective surface configured to redirect the propagation path of at least one photon emitted from the first scintillator among the first pair of adjacent scintillators and passing through the transparent surface, Equipped with, The propagation of the at least one photon is rerouted from the first scintillator to the second scintillator of the first pair of adjacent scintillators. Each of the fifth and sixth scintillators includes a rectangular parallelepiped shape with a triangular shape attached to the first portion. A prismatoid in which the rectangular parallelepiped sides included in the fifth and sixth scintillators are adjacent to each other between the triangular shapes, forming a rectangular parallelepiped portion to which the triangular shapes are not attached, and forming the respective corners of the pair of corner scintillators between the triangular shapes.

13. At least one detector is provided at the end of the first pair of adjacent scintillators opposite to the reflective surface, The prismatoid according to claim 12, wherein the first scintillator of the first pair of adjacent scintillators shares the first detector of the at least one detector with the third scintillator of the second pair of adjacent scintillators.

14. The second scintillator of the first pair of adjacent scintillators is adjacent to the fourth scintillator of the second pair of adjacent scintillators, The prismatoid according to claim 13, wherein the second scintillator shares the second detector of the at least one detector with the fourth scintillator.

15. The prismatoid according to claim 12, wherein the prismatoid is configured to redirect light from the first scintillator of the first pair of adjacent scintillators to at least one of the second scintillator of the first pair of adjacent scintillators, the third scintillator of the second pair of adjacent scintillators, and the fourth scintillator of the second pair of adjacent scintillators.

16. Each of the first scintillator and the second scintillator comprises a first inner surface and a second inner surface substantially parallel thereto. The prismatoid according to claim 15, wherein the first inner surface and the second inner surface of the first scintillator or the second scintillator are configured to reflect light between their inner surfaces in order to transmit substantially all of the light from the prismatoid to at least one detector.

17. The prismatoid according to claim 12, wherein the prismatoid is substantially formed as at least one of at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one pyramidal tower, at least one cuboid, at least one wedge, at least one pyramid, at least one truncated pyramid, or at least one subsphere.

18. A system for non-invasive medical imaging, At least one prismatoid, At least one detector, A scintillator array comprising a first pair of adjacent scintillators including a first scintillator and a second scintillator, a second pair of adjacent scintillators including a third scintillator and a fourth scintillator, and at least one pair of corner scintillators including a fifth scintillator and a sixth scintillator, Equipped with, The at least one prismatoid is configured to redirect light between adjacent scintillators forming the first or second pair of the scintillator array, The at least one detector is provided at the end of the scintillator array opposite to the at least one prismatoid, The at least one prismatoid is substantially formed as at least one of at least one prism, at least one antiprism, at least one truncated pyramid, at least one triangle, at least one pyramidal tower, at least one cuboid, at least one wedge, at least one pyramid, at least one truncated pyramid, and at least one subsphere, Each of the fifth and sixth scintillators includes a rectangular parallelepiped shape with a triangular shape attached to its upper part. The system is characterized in that the sides of the rectangular parallelepiped shapes included in the fifth scintillator and the sixth scintillator are adjacent to each other between the triangular shapes, forming rectangular parallelepiped portions to which the triangular shapes are not attached, and forming the respective corners of the pair of corner scintillators between the triangular shapes.

19. The system according to claim 18, further comprising a processor configured to perform positron emission tomography (PET) by reading out one-sided interaction positions (DOI).

20. The scintillator array, the at least one prismatoid, and the at least one detector are asymmetrically aligned. The system according to claim 19, wherein the first detector of the at least one detector is adjacent to the second detector of the at least one detector, thereby expanding the area for performing the PET.

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