CN115097509A

CN115097509A - Detector assembly and imaging method corresponding to imaging system

Info

Publication number: CN115097509A
Application number: CN202210742735.6A
Authority: CN
Inventors: 许晓莼
Original assignee: Shanghai United Imaging Healthcare Co Ltd
Current assignee: Shanghai United Imaging Healthcare Co Ltd
Priority date: 2022-06-28
Filing date: 2022-06-28
Publication date: 2022-09-23

Abstract

The embodiment of the specification provides a detector assembly and an imaging method corresponding to an imaging system. The detector assembly includes at least two first crystal modules, at least one second crystal module, and at least one non-detection module. The at least two first crystal modules may be configured to detect a first portion of the photons and generate a first scintillation. Each of the at least two first crystal modules has a first detection capability. At least one second crystal module may be configured to detect a second portion of the photons and produce a second scintillation. Each of the at least one second crystal module has a second detection capability. Wherein the second detection capability is less than the first detection capability. The at least two first crystal modules may be spaced apart by at least one of the at least one second crystal module or the at least one non-detection module.

Description

Detector assembly and imaging method corresponding to imaging system

Technical Field

Embodiments of the present disclosure relate to the field of radiation detection, and more particularly, to a detector assembly and an imaging method corresponding to the imaging system.

Background

A detector assembly in an imaging device, such as a Positron Emission Tomography (PET) device, typically includes a scintillation crystal and a sensor coupled thereto. A scintillation crystal can be used to detect photons emitted by an object (e.g., a patient) and produce a scintillation, and a sensor can be used to detect the scintillation. Imaging data may be generated based on the detected flicker. Typically, the detector assembly in an imaging device contains a large number of scintillation crystals, which are expensive. Therefore, it is desirable to design a lower cost detector assembly.

Disclosure of Invention

One aspect of the present description provides a detector assembly. The detector assembly includes at least two first crystal modules, at least one second crystal module, and at least one non-detection module. The at least two first crystal modules may be configured to detect a first portion of the photons and generate a first scintillation. Each of the at least two first crystal modules has a first probing capability. At least one second crystal module can be configured to detect a second portion of the photons and produce a second scintillation. Each of the at least one second crystal module has a second probing capability. Wherein the second detection capability is less than the first detection capability. The at least two first crystal modules may be spaced apart by at least one of the at least one second crystal module or the at least one non-detection module.

In some embodiments, each of the at least two first crystal modules or the at least one second crystal module may include at least two crystal units.

In some embodiments, each of the at least two crystal units may be comprised of one or a combination of cerium-doped lutetium yttrium silicate, cerium-doped lutetium yttrium silicate, bismuth germanate, sodium iodide, cesium iodide, gadolinium silicate, calcium fluoride, cesium fluoride, barium fluoride.

In some embodiments, the probe assembly may further include a sensor. The sensor may be configured to detect the first and second flashes. The sensor may include: at least one first sensing module configured to detect a first portion of the first and second flashes; and at least one second sensing module configured to detect a second portion of the first and second flashes. Each of the at least one first sensing module has a third detection capability. Each of the at least one second sensing module has a fourth detection capability. The fourth detectability is less than the third detectability.

In some embodiments, the sensor may further comprise at least one second non-detection module. The at least one first sensing module may be spaced apart by at least one of the at least one second sensing module or the at least one second non-detecting module.

In some embodiments, each of the at least one first sensing module or the at least one second sensing module comprises at least two sensing units.

In some embodiments, each of the at least two sensing units may be comprised of one or a combination of a silicon photomultiplier, a photomultiplier tube.

In some embodiments, each of the at least one non-detection module or the at least one second non-detection module may be comprised of one of glass, air, or a combination thereof.

In some embodiments, the at least two first crystal modules may include at least two first crystal units. The at least one second crystal module may include at least two second crystal units. The at least one non-detection module may comprise at least two non-detection units. The number of the at least two first crystal units accounts for 30% -99% of the sum of the number of the at least two first crystal units, the number of the at least two second crystal units and the number of the at least two non-detection units.

Another aspect of the present specification provides an imaging method corresponding to the imaging system. The imaging system may include a detector assembly. The probe assembly may include: at least two first crystal modules configured to detect a first portion of photons and generate a first scintillation, each of the at least two first crystal modules having a first detection capability; at least one second crystal module configured to detect a second portion of the photons and produce a second scintillation and configured to randomly space the at least two first crystal modules, each of the at least one second crystal modules having a second detection capability, and the second detection capability being less than the first detection capability; and a sensor coupled to the at least two first crystal modules and/or the at least one second crystal module, the sensor configured to detect the first scintillation and/or the second scintillation. The method can comprise the following steps: generating first imaging data based on the detected first glints; generating second imaging data based on the detected second flicker; correcting the second imaging data based on the first imaging data; and generating an image based on at least a portion of the first imaging data and the corrected second imaging data.

The beneficial effects that may be brought by the embodiments of the present description include, but are not limited to: (1) the second crystal module and/or the non-detection module made of cheaper materials are/is used for replacing part of the first crystal module in the detector module, compared with the method that the detector module is constructed by only using the first crystal module, the construction cost of the detector assembly can be reduced, and meanwhile, the reconstructed image can be ensured to have relatively high quality by controlling the proportion of the first crystal module; (2) compared with the method that only the first crystal modules are used for constructing the detector modules, when the first crystal modules with the same number are used for constructing the sparse detector modules, the detection areas corresponding to the detector modules are larger, and the imaging time can be shortened; (3) the second sensing module and/or the second non-detection module which are made of cheaper materials are used for replacing part of the first sensing module in the sensor, and compared with the method that only the first sensing module is used for constructing the sensor, the construction cost of the detector assembly can be reduced; (4) the imaging data corresponding to the second crystal module is corrected based on the first imaging data corresponding to the first crystal module, and the quality of the reconstructed image can be improved. It is to be noted that different embodiments may produce different advantages, and in different embodiments, any one or combination of the above advantages may be produced, or any other advantages may be obtained.

Drawings

The present description will be further explained by way of exemplary embodiments, which will be described in detail by way of the accompanying drawings. These embodiments are not intended to be limiting, and in these embodiments like numerals refer to like structures, wherein:

FIG. 1 is a schematic view of an exemplary imaging system shown in accordance with some embodiments of the present description;

FIG. 2 is a schematic diagram of an arrangement of portions of modules in an exemplary detector assembly, according to some embodiments herein;

FIG. 3 is a schematic diagram of an arrangement of portions of modules in an exemplary detector assembly, according to some embodiments herein;

FIG. 4 is a schematic illustration of a lookup table corresponding to a portion of modules in an exemplary detector assembly in accordance with some embodiments of the present description;

FIG. 5 is a block diagram of an exemplary imaging system shown in accordance with some embodiments of the present description;

FIG. 6 is a flow chart of an imaging method corresponding to an exemplary imaging system shown in some embodiments in accordance with the present description.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only examples or embodiments of the present description, and that for a person skilled in the art, the present description can also be applied to other similar scenarios on the basis of these drawings without inventive effort. Unless otherwise apparent from the context, or otherwise indicated, like reference numbers in the figures refer to the same structure or operation.

It should be understood that "system", "device", "unit" and/or "module" as used in this specification is a method for distinguishing different components, elements, parts or assemblies at different levels. However, other words may be substituted by other expressions if they accomplish the same purpose.

As used in this specification and the appended claims, the terms "a," "an," "the," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural, unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.

Flow charts are used in this description to illustrate operations performed by a system according to embodiments of the present description. It should be understood that the preceding or following operations are not necessarily performed in the exact order in which they are performed. Rather, the various steps may be processed in reverse order or simultaneously. Meanwhile, other operations may be added to or removed from these processes.

Fig. 1 is a schematic diagram of an exemplary imaging system, shown in accordance with some embodiments of the present description.

As shown in fig. 1, imaging system 100 may include an imaging device 110, a processing device 120, a storage device 130, one or more terminals 140, and a network 150. The components of the imaging system 100 may be connected in various ways. For example, the imaging device 110 may be connected to the processing device 120 through a network 150. As another example, imaging device 110 may be directly connected to processing device 120, as shown by the dashed double-headed arrow connecting imaging device 110 and processing device 120 in FIG. 1. As another example, storage device 130 may be connected to processing device 120 directly or through network 150. As another example, the terminal 140 may be connected to the processing device 120 directly (as shown by the dashed double-headed arrow connecting the terminal 140 and the processing device 120 in fig. 1) or through the network 150.

In some embodiments, the imaging device 110 may be configured to detect radiation and generate data related to the detected radiation. The radiation may include a particle beam (e.g., neutrons, protons, mesons, heavy ions), a photon beam (e.g., X-rays, gamma-rays, alpha-rays, beta-rays, ultraviolet, laser), and the like, or any combination thereof. In some embodiments, the imaging device 110 may be configured to acquire imaging data related to at least a portion of a subject. For example, the imaging device 110 may scan an object or portion thereof located within its detection region and generate imaging data related to the object or portion thereof. The imaging data may include images, projection data, and the like, or any combination thereof. In some embodiments, the imaging data may include two-dimensional imaging data, three-dimensional imaging data, four-dimensional imaging data, or the like, or any combination thereof. The object may be a biological object or a non-biological object. For example, the object may include a patient, an animal, an artificial object (e.g., a phantom). Also for example, the object may include a portion, organ, or tissue of a patient, such as a head, neck, chest, heart, stomach, blood vessel, soft tissue, tumor, nodule, or the like, or any combination thereof. In some embodiments, the imaging device 110 may comprise a single modality imaging device. For example, the imaging device 110 may include a Positron Emission Tomography (PET) device, a Single Photon Emission Computed Tomography (SPECT) device, a Photon Counting Computed Tomography (PCCT) device, and the like. In some embodiments, the imaging device 110 may comprise a multi-modality imaging device. For example, a PET-CT device, a PET-MR device, a SPECT-CT device, a SPECT-MR device, a SPECT-PET device, the like, or any combination thereof.

In some embodiments, processing device 120 may process data obtained from imaging device 110, terminal 140, or storage device 130. The processing device 120 may be a Central Processing Unit (CPU), a Digital Signal Processor (DSP), a system on chip (SoC), a microcontroller unit (MCU), etc., or any combination thereof. In some embodiments, the processing device 120 may be a single server or a group of servers. The server group may be centralized or distributed. In some embodiments, the processing device 120 may be local or remote. For example, processing device 120 may access information and/or data stored in imaging device 110, terminal 140, and/or storage device 130 via network 150. As another example, processing device 120 may be directly connected to imaging device 110 (as shown by the dashed double-headed arrow connecting imaging device 110 and processing device 120 in FIG. 1), terminal 140 (as shown by the dashed double-headed arrow connecting terminal 140 and processing device 120 in FIG. 1), and/or storage device 130 to access information and/or data. In some embodiments, the processing device 120 may be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an inter-cloud, a cloudy, etc., or any combination thereof.

Storage device 130 may store data and/or instructions. In some embodiments, storage device 130 may store data obtained from terminal 140 and/or processing device 120. In some embodiments, storage device 130 may store data and/or instructions for processing device 120 to perform the exemplary operations described in this specification. In some embodiments, storage 130 may include mass storage, removable storage, volatile read-write memory, read-only memory (ROM), and the like, or any combination thereof. Exemplary mass storage devices may include magnetic disks, optical disks, solid state drives, and the like. Exemplary removable memories may include flash drives, floppy disks, optical disks, memory cards, compact disks, magnetic tape, and the like. Exemplary volatile read and write memory can include Random Access Memory (RAM). Exemplary RAM may include Dynamic Random Access Memory (DRAM), Double Data Rate Synchronous Dynamic Random Access Memory (DDRSDRAM), Static Random Access Memory (SRAM), thyristor random access memory (T-RAM), zero capacitance random access memory (Z-RAM), and the like. Exemplary ROMs may include Mask ROM (MROM), Programmable ROM (PROM), erasable programmable ROM (PEROM), electrically erasable programmable ROM (eePROM), compact disk ROM (CD-ROM), digital versatile disk ROM, and the like. In some embodiments, storage device 130 may be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an inter-cloud, a cloudy, etc., or any combination thereof.

In some embodiments, the storage device 130 may be connected to the network 150 to communicate with one or more components of the imaging system 100 (e.g., the terminal 140, the processing device 120). One or more components of the imaging system may access data or instructions stored in the storage device 130 over the network 150. In some embodiments, the storage device 130 may be directly connected to or in communication with one or more components of the imaging system 100 (e.g., the terminal 140, the processing device 120). In some embodiments, the storage device 130 may be part of the processing device 120.

The terminal 140 may include a mobile device 140-1, a tablet computer 140-2, a laptop computer 140-3, the like, or any combination thereof. In some embodiments, mobile device 140-1 may include a smart home device, a wearable device, a smart mobile device, a virtual reality device, an augmented reality device, and the like, or any combination thereof. In some embodiments, the smart home devices may include smart lighting devices, smart appliance control devices, smart monitoring devices, smart televisions, smart cameras, interphones, and the like, or any combination thereof. In some embodiments, the wearable device may include a bracelet, a podium, glasses, a helmet, a watch, clothing, a backpack, or the like, or any combination thereof. In some embodiments, the smart mobile device may include a smart phone, a Personal Digital Assistant (PDA), a gaming device, a navigation device, a point of sale (POS), and the like, or any combination thereof. In some embodiments, the virtual reality device and/or the augmented reality device may include a virtual reality helmet, virtual reality glasses, virtual reality eyeshields, augmented reality helmets, augmented reality glasses, augmented reality eyeshields, and the like, or any combination thereof. In some embodiments, the terminal 140 may remotely operate the imaging device 110. In some embodiments, terminal 140 may operate imaging device 110 via a wireless connection. In some embodiments, the terminal 140 may receive information and/or instructions input by a user and transmit the received information and/or instructions to the imaging device 110 or the processing device 120 via the network 150. In some embodiments, the terminal 140 may receive data and/or information from the processing device 120. In some embodiments, the terminal 140 may be part of the processing device 120. In some embodiments, the terminal 140 may be omitted.

The network 150 may facilitate the exchange of information and/or data. In some embodiments, one or more components of imaging system 100 (e.g., imaging device 110, terminal 140, processing device 120, or storage device 130) may send information and/or data to another component in imaging system 100 via network 150. In some embodiments, the network 150 may be any type of wired or wireless network or combination thereof. The network 150 may be and/or include a public network (e.g., the internet), a private network (e.g., a Local Area Network (LAN), a Wide Area Network (WAN)), a wired network (e.g., ethernet), a wireless network (e.g., an 802.11 network, a Wi-Fi network), a cellular network (e.g., a Long Term Evolution (LTE) network), a frame relay network, a virtual private network ("VPN"), a satellite network, a telephone network, a router, a hub, a switch, a server computer, and/or any combination thereof. By way of example only, network 150 may include a cable network, a wired network, a fiber optic network, a telecommunications network, an intranet, the internet, a Local Area Network (LAN), a Wide Area Network (WAN), a Wireless Local Area Network (WLAN), a Metropolitan Area Network (MAN), a Public Switched Telephone Network (PSTN), a bluetooth network, a ZigBee network, a Near Field Communication (NFC) network, the like, or any combination thereof. In some embodiments, the network 150 may include one or more network access points. For example, the network 150 may include wired or wireless network access points, such as base stations and/or internet exchange points, through which one or more components of the imaging system 100 may connect to the network 150 to exchange data and/or information.

In some embodiments, a radiotracer may be injected into a subject (e.g., a patient) and then imaging data acquired by scanning the subject using an imaging device 110 (e.g., a PET device). In some embodiments, the imaging device 110 may include a detector assembly. The detector assembly is configured to detect at least a portion of photons (e.g., gamma photons) emitted by the object and/or generate an electronic signal (e.g., a scintillation pulse). The electronic signals may be further converted to computer readable signals (e.g., digital signals) to generate imaging data. During a scan, a radioactive tracer in the subject decays and emits positrons, which can annihilate with electrons in the surrounding subject and produce photon pairs. Wherein each pair of photons is directed in opposite directions. A detector assembly may be configured to detect at least a portion of the photon pair. A coincidence event can be considered to have occurred when a pair of photons is detected within a coincidence time window. A line of response (LOR) corresponding to the coincidence event can refer to a connection between two portions (e.g., two crystal modules, two crystal units, as described below) in a detection assembly connecting the detection assemblies that detected the pair of photons. The line of response may be used to indicate the emission path of the pair of photons. In some embodiments, the imaging data may include photon data (e.g., position, time, amount), scintillation data (e.g., position, time, amount), coincidence data (e.g., position, time, amount), line of response (LOR) data (e.g., position, time, amount), etc., or any combination thereof, detected by different portions of the detector assembly (e.g., crystal module, crystal cell, as described below). For more description of the imaging data, please refer to fig. 6 and the description thereof, which are not repeated herein.

In some embodiments of the present description, the detector assembly may include a detector module. The detector module may be configured to detect photons and produce a scintillation. The detector module may include at least two first crystal modules (e.g., dot-filled blocks as shown in fig. 2-3) and at least one spacing module (e.g., dashed-line filled blocks and blank blocks as shown in fig. 2-3). In some embodiments, the at least one spacing module may be configured to randomly space apart the at least two first crystal modules. As used herein, "random" may mean that at least one spacer module or at least two first crystal modules are not arranged in a particular shape (e.g., L-shape, T-shape) nor are they arranged periodically. By way of example only, a portion of the at least two first crystal modules and the at least one spacer module may be in any of the arrangements a-l shown in FIG. 2. In some embodiments, at least a portion of the at least one spacing module may be spaced apart by at least two first crystal modules according to a certain rule (e.g., in a particular shape, periodic arrangement). The at least one spacer module may be constructed of a lower cost material than the at least two first crystal modules. Thus, by introducing spacer modules instead of part of the first crystal module, the cost of the detector assembly can be reduced compared to a detector assembly constructed with only the first crystal module. In some embodiments of the present description, a detector module that includes a spacing module may also be referred to as a sparse detector module.

In some embodiments, the at least one spacing module may include at least one second crystal module and/or at least one non-detection module. For example, the at least one spacing module may comprise at least one second crystal module. For another example, the at least one spacing module may include at least one non-probing module. For another example, the at least one spacing module can include a combination of at least one non-detection module and at least one second crystal module. In some embodiments, the at least two first crystal modules may be spaced apart (e.g., randomly, regularly) by at least one of the at least one second crystal module and/or the at least one non-spaced module. For example, the at least one second crystal module may be regularly spaced apart from the at least two first crystal modules, and the at least one non-detection module may be randomly spaced apart from the at least two first crystal modules. For another example, the at least one second crystal module and the at least one non-detection module may be randomly or regularly spaced apart from the at least two first crystal modules. Taking fig. 2 as an example, a portion of the at least two first crystal modules, the at least one second crystal module, and the at least one non-detection module may be arranged as shown in any one of a-l.

In some embodiments, the at least two first crystal modules may be configured to detect a first portion of the photons and generate a first scintillation. The at least one second crystal module may be configured to detect a second portion of the photons and generate a second scintillation. At least one of the non-detection modules does not have the capability to detect photons, i.e. the non-detection module cannot detect photons incident thereon. In some embodiments, each of the at least two first crystal modules has a first detection capability (i.e., the capability to detect photons and/or produce scintillation). Each of the at least one second crystal module has a second detection capability (i.e., the capability of detecting photons and/or producing scintillation). The second detection capability may be less than the first detection capability, i.e., a first crystal module may be able to detect more photons or produce more scintillation than a second crystal module for the same incident photon. For more description of the first detection capability or the second detection capability, reference may be made to fig. 6 and the description thereof, which are not repeated herein. It is noted that in some embodiments, a photon may include only the first portion and the second portion described above. In some embodiments, the photons may include other portions in addition to the first and second portions described above, such as portions of the photons not detected by the detector.

In some embodiments, the detectability of the crystal module may be related to the type of material from which it is constructed. In some embodiments, the first crystal module and/or the second crystal module may be composed of one or a combination of cerium-doped Lutetium Yttrium Silicate (LYSO), cerium-doped Lutetium Silicate (LSO), Bismuth Germanate (BGO), sodium iodide, cesium iodide, gadolinium silicate, calcium fluoride, cesium fluoride, barium fluoride, and the like. For example, the first crystal module may be comprised of LYSO and the second crystal module may be comprised of BGO (which has a detectability less than LYSO). As another example, the first crystal module can be comprised of LSO and the second crystal module can be comprised of BGO (which has a lower detectability than LSO). For another example, the first crystal module may be composed of cesium iodide and the second crystal module may be composed of sodium iodide (which has a lower detectivity than cesium iodide). In some embodiments, the more probing of the material, the more expensive the cost may be. Therefore, by introducing the second crystal module instead of part of the first crystal module, the cost of the detector assembly can be reduced compared to a detector assembly constructed with only the first crystal module.

In some embodiments, the non-detection modules may be comprised of one or a combination of light permeable materials (e.g., glass), air (i.e., the non-detection modules are empty). For example, each of the at least one non-probing modules may be left empty. For another example, each of the at least one non-detection modules can be constructed of a light permeable material. For another example, a portion of the at least one non-detection module may be left empty, and another portion of the at least one non-detection module may be made of a light-permeable material. In some embodiments, the light permeable material or the void arrangement is selected to be less expensive than the material comprising the first crystal module or the material comprising the second crystal module. Therefore, by introducing a non-detection module instead of part of the first crystal module and/or the second crystal module, the cost of the detector assembly may be further reduced compared to a detector assembly constructed with only the first crystal module and/or the second crystal module.

In some embodiments, each of the at least two first crystal modules or the at least one second crystal module may include at least two crystal units. The number of at least two crystal units may be greater than a threshold, such as 100, 225, 400, etc. In some embodiments, at least two crystal units may be arranged in a matrix form, such as 10 × 10, 15 × 15, 20 × 20, and the like. Each crystal unit may be composed of one or a combination of cerium-doped lutetium yttrium silicate, cerium-doped lutetium yttrium silicate, bismuth germanate, sodium iodide, cesium iodide, gadolinium silicate, calcium fluoride, cesium fluoride, barium fluoride, and the like. In some embodiments, the at least two first crystal modules may include at least two first crystal units. The at least two second crystal modules may include at least two second crystal units. When the crystal module is manufactured, the crystal can be directly cut into the size of the first crystal module or the size of the second crystal module, compared with the size of the first crystal unit or the second crystal unit, the preparation process is simpler, and the cost for manufacturing the detector assembly can be reduced.

In some embodiments, the size (e.g., volume, length, width, height) of a second crystal module or the size (e.g., volume, length, width, height) of a non-detection module may be the same or different than the size (e.g., volume, length, width, height) of the first crystal module. In some embodiments, the at least one non-probing module may comprise at least two non-probing units. The size (e.g. volume, length, width, height) of a second crystal unit or the size (e.g. volume, length, width, height) of a non-detecting unit may be the same as or different from the size (e.g. volume, length, width, height) of the first crystal unit. In some embodiments, to simultaneously ensure the quality of the imaged image and reduce the manufacturing cost of the detector assembly, the number of first crystal units in the detector module may account for 10% -99%, 30% -99%, 50% -80%, etc. of the sum of the number of first crystal units, the number of second crystal units, and the number of non-detection units in the detector module. The number of second crystal cells in the detector module accounts for 10% -99%, 30% -99%, 50% -80% and the like of the sum of the number of second crystal cells and the number of non-detection cells in the detector module. Illustratively, when the first crystal unit is constructed from LYSO and the second crystal unit is constructed from BGO, and each is 50%, the cost of the detector assembly may be 2/3 for a detector assembly constructed from LYSO alone. For another example, when the first crystal unit is constructed of LYSO, the second crystal unit is constructed of BGO, the non-detection modules are empty, and each occupies 1/3, the cost of the detector assembly is 4/9 for a detector assembly constructed of LYSO only.

The above description of the detector module configuration is for illustrative purposes only and is not limiting. In some embodiments, each of the first crystal module, the second crystal module, and the non-detection module may include at least one cell. In some embodiments, each of the first crystal module, the second crystal module, and the non-detection module may include only one unit, i.e., the first crystal units in the detector module may be spaced (e.g., randomly or regularly) apart by the second crystal units and/or the non-detection units. In some embodiments, the number of first crystal units included per first crystal module, the number of second crystal units included per second crystal module, and/or the number of non-detection units included per non-detection module may be the same or different. For example, each first crystal module includes at least two first crystal units. Each second crystal module includes at least one second crystal unit. Each non-detection module comprises at least one non-detection unit.

In some embodiments, the first imaging data may be generated based on the first portion or the first scintillation of the detected photons. The first imaging data may include first imaging sub-data corresponding to a photon portion or a scintillation portion detected by each of the first crystal modules. Second imaging data may be generated based on a second portion of the detected photons or a second scintillation. The second imaging data may include second imaging sub-data corresponding to the photon portion or the scintillation portion detected by each of the second crystal modules. At least a portion of the first imaging data and the second imaging data may be used to generate an image. In some embodiments, the image may be generated using only the first imaging data. In this case, to reduce the cost of the detector assembly, the spacer module may include a non-detection module and/or a second crystal module constructed of a less expensive material. In some embodiments, the first imaging data and the second imaging data may be used to generate an image. In some embodiments, the image may be generated according to a reconstruction algorithm. Exemplary reconstruction algorithms may include a maximum likelihood-maximum expectation (MLEM) algorithm, an Ordered Subset Expectation Maximization (OSEM) algorithm. Filtered Back Projection (FBP) algorithm, the like, or any combination thereof.

Since the detection capability of the second crystal module is smaller than that of the first crystal module, the number of scintillations (or photons) detected by the second crystal module may be less than that (or photons) detected by the first crystal module, assuming the incident photon intensity is the same during the detection process, resulting in the quality of the second imaging data being inferior to that of the first imaging data. To ensure or improve the quality of the image, the second imaging data may be corrected using the first imaging data, and an image may be generated using the first imaging data and at least a portion of the corrected second imaging data. In some embodiments, taking a specific second crystal module (e.g., block 310 in fig. 3) as an example, the first imaging sub-data corresponding to the adjacent first crystal module (e.g., blocks 312 and 314 in fig. 3) may be used to correct the second imaging sub-data corresponding to the second crystal module. As used herein, "adjacent" may refer to the number of modules between the first and second crystal modules being less than a number threshold (e.g., 1, 2, 3) or the distance being less than a distance threshold. In some embodiments, the number threshold or distance threshold may be determined based on parameters of the detector assembly (e.g., a size of the first crystal module, a size of the second crystal module, a detection capability of the first crystal module, a detection capability of the second crystal module). Further description regarding correcting the second imaging data and/or generating the image may be found in the description of fig. 6 below, and will not be repeated here.

In some embodiments, as described above, the non-detection module does not have the capability to detect photons, i.e., cannot detect photons incident thereon, which reduces the sensitivity of the detector assembly and may have an effect on the quality of the image. To ensure or improve the quality of the image, third imaging data corresponding to at least one non-detection module may be estimated using at least a portion of the first imaging data or the second imaging data (or the corrected second imaging data), and an image may be generated using at least a portion of the first imaging data, the corrected second imaging data, or the third imaging data. In some embodiments, taking a specific non-detection module (e.g., block 320 in fig. 3) as an example, at least a portion of the first imaged sub-data corresponding to the adjacent first crystal module (e.g., blocks 322, 324, and 326 in fig. 3) or the corrected second imaged sub-data corresponding to the adjacent second crystal module may be used to estimate the third imaged sub-data corresponding to the non-detection module. As used herein, "adjacent" may mean that the number of modules between the first crystal module or the second crystal module and the non-detection module is less than a number threshold (e.g., 1, 2, 3) or the distance is less than a distance threshold. In some embodiments, the number threshold or the distance threshold may be determined based on parameters of the detector assembly (e.g., a size of the non-detection module, a size of the first crystal module, a size of the second crystal module, a detection capability of the first crystal module, a detection capability of the second crystal module). Further description of estimating the third imaging data and/or generating the image may be found in the description of fig. 6 below, and will not be repeated here.

In some embodiments, the probe assembly may further include a sensor. The sensor is configured to detect the first and/or second glints described above and/or generate a corresponding computer readable signal. The imaging data (e.g., first imaging data, second imaging data) may be generated based on the detected first glints and/or second glints and/or the generated computer readable signals.

In some embodiments, the sensor may be directly connected to the detector module or indirectly through a light-guiding element (e.g., an optical fiber). In some embodiments, the modules included in the detector module (e.g., the first crystal module, the second crystal module, the non-detection module) and the modules included in the sensor may be one-to-one connected. In this case, the number of modules comprised in the sensor and the number of modules comprised in the detector module are the same. In some embodiments, the modules included in the detector module (e.g., the first crystal module, the second crystal module, the non-detection module) and the modules included in the sensor may be a many-to-one connection. In this case, the number of modules included in the detector module is greater than the number of modules included in the sensor. In some embodiments, the modules included in the sensor are connected only to at least a portion of the at least two first crystal modules and the at least one second crystal module, and not to the at least one non-detection module.

In some embodiments, the modules in the sensor may be constructed using the same components, such as silicon photomultipliers (sipms) (e.g., digital silicon photomultipliers), photomultiplier tubes (PMTs), photodiodes (e.g., avalanche photodiodes), active pixel sensors, electrical coupling devices, photoresistors, phototransistors, and the like. In some embodiments, the sensor may include at least one first sensing module and at least one second spacing module. Similar to the at least two first crystal modules and the at least one first spacing module, the at least one second spacing module is configured to space apart (e.g., randomly, regularly) the at least one first sensing module. The at least one second spacer module may be constructed using lower cost components or materials than the at least one first sensing module. Therefore, by introducing the second spacer module instead of part of the first sensing module, the cost of the detector assembly may be reduced compared to a detector assembly constructed with only the first sensing module. In some embodiments of the present description, the sensor comprising the second spacing module may also be referred to as a sparse sensor.

In some embodiments, a first crystal module may be coupled to a first sensing module and a second crystal module may be coupled to a second sensing module. In some embodiments, the first and second crystal modules may be respectively coupled with the first sensing module. In some embodiments, a barrier material may be placed between the non-detection module and the sensor to prevent radiation (e.g., photons) from damaging the sensor.

In some embodiments, the at least one second spacing module may include at least one second sensing module and/or at least one second non-detecting module. For example, the at least one second spacing module may include at least one second sensing module. For another example, the at least one second spacing module can include at least one second non-detection module. For another example, the at least one second spacing module may include a combination of at least one second detection module and at least one second sensing module. In some embodiments, the at least one first sensing module may be spaced apart (e.g., randomly or regularly) by at least one of the at least one second sensing module or the at least one second non-detecting module. For example, the at least one second sensing module may be regularly spaced apart from the at least one first sensing module, and the at least one second non-detecting module may be randomly spaced apart from the at least one first sensing module. For another example, the at least one second sensing module and the at least one second non-detecting module may be spaced apart from the at least one first sensing module randomly or according to a certain rule.

In some embodiments, the at least one first sensing module may be configured to detect a first portion of the first glint and the second glint; that is, the at least one first sensing module may detect at least a portion of the first glint and/or at least a portion of the second glint. The at least one second sensing module may be configured to detect a second portion of the first glints and the second glints; that is, the at least one second sensing module may detect at least a portion of the first flicker and/or at least a portion of the second flicker. At least one of the second non-detection modules does not have the capability to detect photons, i.e. the second non-detection module is not capable of detecting the scintillation projected thereon. In some embodiments, each of the at least one first sensing modules has a third detection capability (i.e., a capability of detecting flicker). Each of the at least one second sensing modules has a fourth detection capability (i.e., a capability of detecting flicker). The fourth detection capability may be less than the second detection capability.

In some embodiments, the detection capabilities of the sensing module may be related to the type of elements that make up it. In some embodiments, the first sensing module and/or the second sensing module may be comprised of one or a combination of silicon photomultipliers (sipms) (e.g., digital silicon photomultipliers sipms), photomultiplier tubes (PMTs), photodiodes (e.g., avalanche photodiodes), active pixel sensors, electrical coupling devices, photoresistors, phototransistors, and the like. For example, the first sensing module may be comprised of an SiPM and the second sensing module may be comprised of a PMT. In some embodiments, the stronger the detection capability of the element, the more expensive the cost may be. Thus, by introducing the second sensing module in place of a portion of the first sensing module, the cost of the detector assembly may be reduced as compared to a detector assembly constructed with only the first sensing module.

In some embodiments, the second non-detection module may be comprised of one or a combination of light permeable material (e.g., glass), air (i.e., the second non-detection module is empty). For example, each of the at least one second non-detection module may be left empty. For another example, each of the at least one second non-detection modules may be constructed of a light permeable material. For another example, a portion of the at least one second non-detection module may be left empty, and another portion of the at least one second non-detection module may be made of a light permeable material. In some embodiments, the light permeable material or the void arrangement is selected to be less expensive than the material comprising the first sensing module or the material comprising the second sensing module. Thus, by introducing a second non-detection module instead of part of the first and/or second sensing module, the cost of the detector assembly may be further reduced compared to a detector assembly constructed with only the first and/or second sensing module.

In some embodiments, each of the at least one first sensing module or the at least one second sensing module may include at least one sensing unit (e.g., at least two sensing units). In some embodiments, the size (e.g., volume, length, width, height) of a second sensing module or the size (e.g., volume, length, width, height) of a second non-detecting module may be the same or different than the size (e.g., volume, length, width, height) of the first sensing module. In some embodiments, the at least one second non-probing module may comprise at least two second non-probing units. The size (e.g. volume, length, width, height) of a second sensing unit or the size (e.g. volume, length, width, height) of a second non-detecting unit may be the same or different from the size (e.g. volume, length, width, height) of the first sensing unit.

It should be noted that the foregoing description is provided for the purpose of illustration only, and is not intended to limit the scope of the present specification. Besides being applied to the field of medical imaging, the detector assembly can also be applied to the fields of security inspection, scientific experiments, energy detection, nuclear cameras, gas detection and the like.

FIG. 5 is an exemplary block diagram of an imaging system according to some embodiments of the present description. The imaging system 500 may include a first determination module 510, a second determination module 520, a correction module 530, and a generation module 540.

Imaging system 500 (e.g., imaging system 100) may include an imaging device (e.g., imaging device 110). The imaging device may include a detector assembly. The detector assembly may include at least two first crystal modules and at least one second crystal module. The at least two first crystal modules may be configured to detect a first portion of the photons and generate a first scintillation. The at least one second crystal module may be configured to detect a second portion of the photons and generate a second scintillation, and to space the at least two first crystal modules apart (e.g., randomly or regularly). In some embodiments, each of the at least two first crystal modules may have a first detection capability (i.e., the capability to detect photons and/or produce scintillation) and each of the at least one second crystal modules may have a second detection capability (i.e., the capability to detect photons and/or produce scintillation). The second detection capability is less than the first detection capability, i.e., one first crystal module is able to detect more photons or produce more scintillation than one second crystal module for the same incident photon. In some embodiments, the detector assembly may include at least one non-detection module that does not have detection capabilities. The at least two first crystal modules may be spaced apart by at least one of the at least one second crystal module or the at least one non-detection module, and further description of the imaging system 500, the imaging device, or the detector assembly may be found in fig. 1-3 and will not be repeated here.

The first determination module 510 may be configured to generate first imaging data based on the first portion of the detected photons and/or the first glints. In some embodiments, the first imaging data may include first imaging sub-data corresponding to the photon portion or the scintillation portion detected by each of the first crystal modules. Exemplary first imaging data can include photon data (e.g., position, time, amount), scintillation data (e.g., position, time, amount), coincidence event data (e.g., position, time, amount), line of response (LOR) data (e.g., position, time, amount), etc., or any combination thereof, detected by each first crystal module.

The second determination module 520 may be configured to generate second imaging data based on the second portion of the detected photons and/or the second glints. Similar to the first imaging data, exemplary second imaging data may include photon data (e.g., location, time, amount), scintillation data (e.g., location, time, amount), coincidence event data (e.g., location, time, amount), line of response (LOR) data (e.g., location, time, amount), and the like, or any combination thereof, detected by each second crystal module.

The correction module 530 may be configured to correct the second imaging data based on the first imaging data. As depicted in fig. 1, since the detection capability of the second crystal module is inferior to that of the first crystal module, the number of scintillations (or photons) detected by the second crystal module may be less than that (or photons) detected by the first crystal module, assuming the incident photon intensity is the same during the detection process, resulting in the second imaging data being inferior in quality to the first imaging data. In some embodiments, the second imaging data may be corrected based on the first detectability of the first crystal module, the second detectability of the second crystal module, and the first imaging data. Further description regarding the correction of the second imaging data based on the first imaging data can be found in fig. 6 and its associated description.

The generating module 540 may be configured to generate an image based on at least a portion of the first imaging data and the corrected second imaging data. In some embodiments, the image may be generated using a reconstruction algorithm. Exemplary reconstruction algorithms may include a maximum likelihood-maximum expectation (MLEM) algorithm, an Ordered Subset Expectation Maximization (OSEM) algorithm. Filtered Back Projection (FBP) algorithm, the like, or any combination thereof.

It should be understood that the illustrated system and its modules may be implemented in a variety of ways. For example, in some embodiments, the system and its modules may be implemented in hardware, software, or a combination of software and hardware. Wherein the hardware portion may be implemented using dedicated logic; the software portions may be stored in a memory for execution by a suitable instruction execution system, such as a microprocessor or specially designed hardware. Those skilled in the art will appreciate that the methods and systems described above may be implemented using computer executable instructions and/or embodied in processor control code, such code being provided, for example, on a carrier medium such as a diskette, CD-or DVD-ROM, a programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The system and its modules in this specification may be implemented not only by hardware circuits such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., but also by software executed by various types of processors, for example, or by a combination of hardware circuits and software (e.g., firmware).

It should be noted that the above description of the imaging system 500 and its modules is for convenience of description only and should not limit the present disclosure to the scope of the illustrated embodiments. It will be appreciated by those skilled in the art that, given the teachings of the present system, any combination of modules or sub-system configurations may be used to connect to other modules without departing from such teachings. For example, the first determining module 510, the second determining module 520, the correcting module 530 and the generating module 540 may share one storage module, and each module may have a respective storage module. Such variations are within the scope of the present description.

Fig. 6 is a flowchart of an imaging method corresponding to an exemplary imaging system, shown in accordance with some embodiments of the present description.

An imaging system (e.g., imaging system 100) may include an imaging device (e.g., imaging device 110). The imaging device may include a detector assembly. The detector assembly may include at least two first crystal modules and at least one second crystal module. The at least two first crystal modules may be configured to detect a first portion of the photons and generate a first scintillation. The at least one second crystal module may be configured to detect a second portion of the photons and generate a second scintillation, and to space the at least two first crystal modules apart (e.g., randomly or regularly). In some embodiments, each of the at least two first crystal modules may have a first detection capability (i.e., the capability to detect photons and/or produce scintillation) and each of the at least one second crystal modules may have a second detection capability (i.e., the capability to detect photons and/or produce scintillation). The second detection capability is less than the first detection capability, i.e., one first crystal module is able to detect more photons or produce more scintillation than one second crystal module for the same incident photon. In some embodiments, the detector assembly may include at least one non-detection module that does not have detection capabilities. The at least two first crystal modules may be spaced apart by at least one of the at least one second crystal module or the at least one non-detection module, and further description of the imaging system, the imaging device, or the detector assembly may be found in fig. 1-3, which are not repeated herein.

At 610, first imaging data is generated based on the first portion and/or the first scintillation of the detected photons. In some embodiments, the first imaging data may include first imaging sub-data corresponding to the photon portion or the scintillation portion detected by each of the first crystal modules. Exemplary first imaging data may include photon data (e.g., position, time, amount), scintillation data (e.g., position, time, amount), coincidence event data (e.g., position, time, amount), line of response (LOR) data (e.g., position, time, amount), etc., or any combination thereof, detected by each first crystal module. Coincidence event data and/or LOR data detected by the crystal module can be determined based on photon data or scintillation data detected by the crystal module. In some embodiments, the location information of a coincidence event can include the locations of two crystal modules that detected a pair of photons corresponding to the coincidence event, the location at which the coincidence event occurred, and the like. In some embodiments, coincidence events on the line of response may be evenly distributed over the two crystal modules and the crystal module therebetween that is on the line of response. In some embodiments, if the time information of the coincidence event includes the time of flight of the coincidence event, which includes the times at which a pair of photons corresponding to the coincidence event are detected by two crystal modules, respectively, the location at which the coincidence event occurred can be determined from the time difference between the two (e.g., on which crystal module the annihilation occurred, the coincidence event can be considered detected by that crystal module).

At 620, second imaging data is generated based on the second portion of the detected photons and/or the second glints. Similar to the first imaging data, exemplary second imaging data may include photon data (e.g., location, time, quantity), scintillation data (e.g., location, time, quantity), coincidence event data (e.g., location, time, quantity), line of response (LOR) data (e.g., location, time, quantity), and the like, or any combination thereof, detected by each second wafer module. For more description, please refer to operation 610, which is not described herein.

In 630, the second imaging data is corrected based on the first imaging data. As depicted in fig. 1, since the detection capability of the second crystal module is inferior to that of the first crystal module, the number of scintillations (or photons) detected by the second crystal module may be less than that (or photons) detected by the first crystal module, assuming the incident photon intensity is the same during the detection process, resulting in the second imaging data being inferior in quality to the first imaging data. In some embodiments, the second imaging data may be corrected based on the first detection capability of the first crystal module, the second detection capability of the second crystal module, and the first imaging data.

In some embodiments, the uniform rod source may be scanned using an imaging device to obtain rod source values corresponding to the crystal modules. Wherein the tracer distribution is (substantially) uniform at any location of the homogeneous rod source, i.e. the photon intensity incident on each crystal module is (substantially) the same. The rod source value corresponding to the crystal module may be related to the data actually detected by the crystal module (e.g., number of photons, number of scintillations, number of coincidence events, number of LORs). For example, the greater the number of photons or coincidence events detected by a crystal module, the greater the rod source value corresponding to the crystal module, the greater the detection capability of the crystal module. Therefore, the rod source value corresponding to the crystal module can be used for characterizing the detection capability of the crystal module. As used herein, "substantially the same" may mean that the deviation of two elements (e.g., tracer distribution at different locations on the rod source, incident light intensity of two crystal modules) is less than a certain threshold, such as 1%, 3%, 5%, etc.

In some embodiments, a lookup table corresponding to a detector module may be constructed based on the first detection capability, the second detection capability, and the arrangement of the detector modules (e.g., fig. 4 shows a lookup table corresponding to a portion of the detector modules). The look-up table includes at least two tiles that correspond one-to-one with the positions of the modules included in the detector module (e.g., at least two first crystal modules, at least one second crystal module, and at least one non-detection module). A lattice block corresponding to a first crystal module may be populated with values characterizing a first detection capability of the first crystal module (e.g., the number "1"), a lattice block corresponding to a non-detection module may be populated with values characterizing a detection capability of the non-detection module (e.g., the number "0"), and a lattice block corresponding to a second crystal module may be populated with values characterizing a second detection capability of the second crystal module (e.g., numbers between 0-1, such as 0.3, 0.5, 0.8).

For the second imaging subdata detected by each of the at least one second crystal module, the second imaging subdata may be corrected based on at least a portion of the first imaging subdata corresponding to its adjacent first crystal module, the detection capability of the first crystal module, or the detection capability of the second crystal module. For example, the second imaging sub-data may be corrected by the following formula (1):

wherein, C ₁ Indicating the photon data (e.g., number of photons), TC, detected by the second crystal module ₁ A value of the rod source, TC, of the second crystal module ₂ And TC ₃ A value representing the rod source of the first crystal module adjacent to the second crystal module, and C _new,1 And the corrected photon data of the second crystal module is shown.

In some embodiments, if the detector assembly includes the at least one non-detection module, the third data corresponding to the at least one non-detection module may be estimated based on at least a portion of the first imaging data and the second imaging data (or the corrected second imaging data). In some embodiments, for each corresponding third imaging sub-data of at least one non-detection module, the third imaging sub-data may be estimated based on the corresponding first imaging sub-data of the first crystal module adjacent to the non-detection module or the corresponding corrected second imaging sub-data of the second crystal module adjacent to the non-detection module. In some embodiments, the statistical value (e.g., mean, median, interpolation) of at least a portion of the first imaged sub-data corresponding to the first crystal module adjacent to the non-detection module or the corrected second imaged sub-data corresponding to the second crystal module adjacent to the non-detection module may be designated as the third imaged sub-data. For example, the third imaging sub-data may be estimated based on the following formula (2) or formula (3):

C ₁ ＝mean(C ₂ ,C ₃ ,C ₄ ) (2)

LOR ₁ ＝mean(LOR ₂ ,LOR ₃ ,LOR ₄ ) (3)

wherein, C ₂ ,C ₃ ,C ₄ Photon data (e.g., number of photons) corresponding to the first crystal module adjacent to the non-detection module, and C ₁ Indicating the estimated photon data (e.g., photon number), LOR, corresponding to the non-detection module ₂ ,LOR ₃ ,LOR ₄ LOR data representing the correspondence of a first crystal module adjacent to the non-probed module, and LOR _new,1 Representing the estimated LOR data for the non-probed module.

At 640, an image is generated based on at least a portion of the first imaging data and the corrected second imaging data. In some embodiments, an image may be generated based on at least a portion of the first imaging data, the corrected second imaging data, or the third imaging data. In some embodiments, the image may be generated using a reconstruction algorithm. Exemplary reconstruction algorithms may include a maximum likelihood-maximum expectation (MLEM) algorithm, an Ordered Subset Expectation Maximization (OSEM) algorithm. Filtered Back Projection (FBP) algorithm, the like, or any combination thereof.

It should be noted that the above description of the imaging method 600 is for convenience of description only and is not limiting. Operation 620 and operation 630 may be omitted, and after the first imaging data is determined, the second imaging data corresponding to the second crystal module or the third imaging data corresponding to the third crystal module may be estimated based on the first imaging data. At 640, an image may be generated based on at least a portion of the first imaging data, the estimated second imaging data, or the estimated third imaging data. Corresponding to each of the at least one second crystal module, second imaging sub-data corresponding to the second crystal module can be estimated based on the first imaging sub-data corresponding to the adjacent first crystal module. In some embodiments, the statistics (e.g., mean, median, interpolation) of the first sub-image data corresponding to the adjacent first crystal module may be designated as the estimated second sub-image data. For example, the second imaged sub-data may be estimated by the following equation (4):

LOR ₅ ＝mean(LOR ₆ ,LOR ₇ ,LOR ₈ ) (4)

wherein, LOR ₆ ,LOR ₇ ,LOR ₈ LOR data representing the first crystal module adjacent to the second crystal module, and LOR ₅ Representing the estimated LOR data corresponding to the second crystal module.

It should be understood that the illustrated system and its modules may be implemented in a variety of ways. For example, in some embodiments, the system and its modules may be implemented in hardware, software, or a combination of software and hardware. Wherein the hardware portion may be implemented using dedicated logic; the software portions may be stored in a memory for execution by a suitable instruction execution system, such as a microprocessor or specially designed hardware. Those skilled in the art will appreciate that the methods and systems described above may be implemented using computer executable instructions and/or embodied in processor control code, for example such code provided on a carrier medium such as a diskette, CD-or DVD-ROM, programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The system and its modules in this specification may be implemented not only by hardware circuits such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., but also by software executed by various types of processors, for example, or by a combination of the above hardware circuits and software (e.g., firmware).

It should be noted that the above description of the imaging system 500 and its modules is merely for convenience of description and should not limit the present disclosure to the illustrated embodiments. It will be appreciated by those skilled in the art that, given the teachings of the system, any combination of modules or sub-system may be configured to interface with other modules without departing from such teachings. For example, the model determining module 210, the convolution kernel determining module 220, and the scattering information determining module 230 may share one storage module, and each module may have its own storage module. Such variations are within the scope of the present disclosure.

The embodiment of the present specification further provides a computer-readable storage medium, where the storage medium stores computer instructions, and after the computer reads the computer instructions in the storage medium, the computer executes an imaging method corresponding to the aforementioned imaging system. The imaging system includes: a probe assembly, the probe assembly comprising: at least two first crystal modules configured to detect a first portion of photons and generate a first scintillation, each of the at least two first crystal modules having a first detection capability; at least one second crystal module configured to detect a second portion of the photons and produce a second scintillation, and configured to randomly space the at least two first crystal modules, each of the at least one second crystal modules having a second detection capability, and the second detection capability being less than the first detection capability; and a sensor coupled to the at least two first crystal modules and/or the at least one second crystal module, the sensor configured to detect the first scintillation and/or the second scintillation. The imaging method comprises the following steps: generating first imaging data based on the detected first glints; generating second imaging data based on the detected second flicker; correcting the second imaging data based on the first imaging data; and generating an image based on at least a portion of the first imaging data and the corrected second imaging data.

Having thus described the basic concept, it will be apparent to those skilled in the art that the foregoing detailed disclosure is to be regarded as illustrative only and not as limiting the present specification. Various modifications, improvements and adaptations to the present description may occur to those skilled in the art, although not explicitly described herein. Such modifications, improvements and adaptations are proposed in the present specification and thus fall within the spirit and scope of the exemplary embodiments of the present specification.

Also, the description uses specific words to describe embodiments of the specification. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the specification is included. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the specification may be combined as appropriate.

Moreover, those skilled in the art will appreciate that aspects of the present description may be illustrated and described in terms of several patentable species or situations, including any new and useful combination of processes, machines, manufacture, or materials, or any new and useful improvement thereof. Accordingly, aspects of this description may be performed entirely by hardware, entirely by software (including firmware, resident software, micro-code, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data block," module, "" engine, "" unit, "" component, "or" system. Furthermore, aspects of the present description may be represented as a computer product, including computer readable program code, embodied in one or more computer readable media.

The computer storage medium may comprise a propagated data signal with the computer program code embodied therewith, for example, on baseband or as part of a carrier wave. The propagated signal may take any of a variety of forms, including electromagnetic, optical, etc., or any suitable combination. A computer storage medium may be any computer-readable medium that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code located on a computer storage medium may be propagated over any suitable medium, including radio, cable, fiber optic cable, RF, or the like, or any combination of the preceding.

Computer program code required for the operation of various portions of this specification may be written in any one or more programming languages, including an object oriented programming language such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C + +, C #, VB.NET, Python, and the like, a conventional programming language such as C, Visual Basic, Fortran2003, Perl, COBOL2002, PHP, ABAP, a dynamic programming language such as Python, Ruby, and Groovy, or other programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or processing device. In the latter scenario, the remote computer may be connected to the user's computer through any network format, such as a Local Area Network (LAN) or a Wide Area Network (WAN), or the connection may be made to an external computer (for example, through the Internet), or in a cloud computing environment, or as a service, such as a software as a service (SaaS).

Additionally, the order in which the elements and sequences of the process are recited in the specification, the use of alphanumeric characters, or other designations, is not intended to limit the order in which the processes and methods of the specification occur, unless otherwise specified in the claims. While various presently contemplated embodiments of the invention have been discussed in the foregoing disclosure by way of example, it is to be understood that such detail is solely for that purpose and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements that are within the spirit and scope of the embodiments herein. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described system on an existing processing device or mobile device.

Similarly, it should be noted that in the preceding description of embodiments of the present specification, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure aiding in the understanding of one or more of the embodiments. This method of disclosure, however, is not intended to imply that more features than are expressly recited in a claim. Indeed, the embodiments may be characterized as having less than all of the features of a single disclosed embodiment.

Where numerals describing the number of components, attributes or the like are used in some embodiments, it is to be understood that such numerals used in the description of the embodiments are modified in some instances by the modifier "about", "approximately" or "substantially". Unless otherwise indicated, "about", "approximately" or "substantially" indicates that the number allows a variation of ± 20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximations that may vary depending upon the desired properties of the individual embodiments. In some embodiments, the numerical parameter should take into account the specified significant digits and employ a general digit-preserving approach. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the range in some embodiments of the specification are approximations, in specific embodiments, such numerical values are set forth as precisely as possible within the practical range.

For each patent, patent application publication, and other material, such as articles, books, specifications, publications, documents, etc., cited in this specification, the entire contents of each are hereby incorporated by reference into the specification. Except where the application history document does not conform to or conflict with the contents of the present specification, it is to be understood that the application history document, as used herein in the present specification or appended claims, is intended to define the broadest scope of the present specification (whether presently or later in the specification) rather than the broadest scope of the present specification. It is to be understood that the descriptions, definitions and/or uses of terms in the accompanying materials of this specification shall control if they are inconsistent or contrary to the descriptions and/or uses of terms in this specification.

Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present disclosure. Other variations are also possible within the scope of this description. Thus, by way of example, and not limitation, alternative configurations of the embodiments of the specification can be considered consistent with the teachings of the specification. Accordingly, the embodiments of the present description are not limited to only those explicitly described and depicted herein.

Claims

1. A detector assembly, comprising:

at least two first crystal modules configured to detect a first portion of photons and generate a first scintillation, each of the at least two first crystal modules having a first detection capability;

at least one second crystal module configured to detect a second portion of the photons and generate a second scintillation, each of the at least one second crystal module having a second detection capability, and the second detection capability being less than the first detection capability; and

at least one non-detection module, the at least two first crystal modules being spaced apart by at least one of the at least one second crystal module or the at least one non-detection module.

2. The detector assembly of claim 1, wherein each of the at least two first crystal modules or the at least one second crystal module comprises at least two crystal units.

3. The detector assembly of claim 2, wherein each of the at least two crystal units is comprised of one or a combination of cerium-doped lutetium yttrium silicate, cerium-doped lutetium silicate, bismuth germanate, sodium iodide, cesium iodide, gadolinium silicate, calcium fluoride, cesium fluoride, barium fluoride.

4. The detector assembly of claim 1, further comprising a sensor configured to detect the first and second flashes, and the sensor comprises:

at least one first sensing module configured to detect a first portion of the first and second flashes, each of the at least one first sensing module having a third detection capability; and

at least one second sensing module configured to detect a second portion of the first and second flashes, each of the at least one second sensing module having a fourth detection capability, and the fourth detection capability being less than the third detection capability.

5. The probe assembly of claim 4, wherein the sensor further comprises:

at least one second non-detection module, the at least one first sensing module being spaced apart by at least one of the at least one second sensing module or the at least one second non-detection module.

6. The detector assembly of claim 4, wherein each of the at least one first sensing module or the at least one second sensing module comprises at least two sensing cells.

7. A detector assembly as claimed in claim 6, wherein each of the at least two sensing units is formed by one or a combination of silicon photomultipliers, photomultiplier tubes.

8. The detector assembly of claim 5, wherein each of the at least one non-detection module or the at least one second non-detection module is comprised of one of glass, air, or a combination thereof.

9. The probe assembly of claim 1,

the at least two first crystal modules comprise at least two first crystal units,

the at least one second crystal module includes at least two second crystal units,

the at least one non-probing module comprises at least two non-probing units, an

The number of the at least two first crystal units accounts for 30% -99% of the sum of the number of the at least two first crystal units, the number of the at least two second crystal units and the number of the at least two non-detection units.

10. An imaging method for an imaging system, the imaging system comprising a detector assembly, the detector assembly comprising:

at least one second crystal module configured to detect a second portion of the photons and produce a second scintillation and configured to randomly space the at least two first crystal modules, each of the at least one second crystal modules having a second detection capability, and the second detection capability being less than the first detection capability; and

a sensor coupled to the at least two first crystal modules and/or the at least one second crystal module, the sensor configured to detect the first glint and/or the second glint, and the method comprising:

generating first imaging data based on the detected first glints;

generating second imaging data based on the detected second flicker;

correcting the second imaging data based on the first imaging data; and

generating an image based on at least a portion of the first imaging data and the corrected second imaging data.