WO2015096770A1 - 多能谱静态ct设备 - Google Patents
多能谱静态ct设备 Download PDFInfo
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- G01V5/00—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity
- G01V5/20—Detecting prohibited goods, e.g. weapons, explosives, hazardous substances, contraband or smuggled objects
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- G01T1/2914—Measurement of spatial distribution of radiation
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- G01V5/226—Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays using tomography
Definitions
- the present disclosure relates to the field of radiation imaging detection technology, and more particularly to a multiplex spectrum static CT apparatus.
- CT technology plays an important role in safety inspections and the like because it can eliminate the influence of object overlap.
- the conventional CT uses the slip ring device to obtain the projection data at different angles by the rotation of the X light source and the detector, and obtains the tomographic image by the reconstruction method, thereby obtaining the internal information of the detected luggage item.
- Multi-spectral analysis refers to the use of a material to distinguish the X-ray absorption properties of different energies to distinguish the material.
- CT technology combined with multi-energy spectrum analysis technology enables the current baggage inspection equipment to reconstruct the atomic number and electron density of any position inside the substance to be detected, to realize the identification of the substance type, and to play a role in the detection of explosives and drugs. Good results.
- Figure 1 illustrates a method in which the slip ring CT uses a single energy X-ray source 110 plus front and rear dual-energy detectors 120 and 130 to achieve energy spectrum analysis.
- the light source and detector can be rotated with the slip ring, and the detector does not need to cover a large angle.
- the low-energy detector 120 and the high-energy detector 130 through which any one of the rays pass are one-to-one correspondence, and it is easy to perform accurate multi-spectral analysis.
- Static CT cancels the slip ring structure adoption
- the cloth light source 210, the detectors 220 and 230 need to cover a wide range of angles or even arranged in the form of a ring, as shown in FIG.
- the ray oblique problem will be caused, and the degree of ray obliqueity at different angles will be different.
- the oblique shot not only brings the difficulty of high and low energy data registration, but also increases the crosstalk between adjacent detectors, resulting in a decrease in the resolution of the reconstructed image.
- the existing CT implementation of multi-energy spectrum analysis also often uses another method, that is, the multi-energy X-ray source plus the single-energy detector is used, and the X-ray source is switched between multiple energies at high speed during the rotation of the slip ring.
- the slip ring rotates at a high speed, resulting in a deviation of the projection angle between the high and low energy data.
- the frequency of the X-ray energy switching is high, the deviation is generally small and negligible, and if Applying this method to static CT requires setting the adjacent X-ray sources in the multi-point source to different energies. Due to cost, process and other factors, the number of X-ray sources cannot be very large, so high- and low-energy data The deviation of the projection angle between the two cannot be ignored, which affects the accuracy of the pluripotency analysis.
- a versatile spectrum static CT device is proposed for one or more problems in the prior art.
- a versatile spectrum static CT apparatus comprising: a transport mechanism carrying a linear motion of an object under inspection; a distributed ray source comprising a plurality of ray source points, the plurality of ray source point settings At least partially surrounding the object to be inspected and emitting X-rays toward the object to be inspected on a plane perpendicular to a direction of motion of the object to be inspected; detecting means including a first row of detectors and an object under inspection a second row of detectors in a direction of motion adjacent to the first row of detectors, the first row of detectors comprising a plurality of detector units having a first type of energy response disposed in communication with the distributed source Receiving X-rays penetrating the object to be inspected on a first plane parallel to the plane, the second row of detectors comprising a plurality of detection units having a second energy response disposed in the distributed radiation source Receiving X-rays penetrating the object to be inspected on a second
- At least one of the first row of detectors and the second row of detectors has a filter.
- each source point is specifically a carbon nanotube X-ray tube.
- the first energy response is primarily responsive to a low energy component in the X-ray
- the second energy response is primarily responsive to a high energy component in the X-ray
- the processing device is based on the first digital signal and the first The two digital signals reconstruct a high energy attenuation coefficient image and a low energy attenuation coefficient image of the object to be inspected.
- the processing means reconstructs an atomic sequence value and an electron density value of the object under inspection based on the first digital signal and the second digital signal.
- the detecting device further comprises a third row of detectors adjacent to the second row of detectors in a moving direction of the object to be inspected, the third row of detectors comprising a third energy response a plurality of detecting units disposed on a third plane parallel to a plane of the distributed ray source, receiving X-rays penetrating the object to be inspected; the collecting device detecting the third row of detectors Converting X-rays into a third digital signal, converting X-rays detected by said third row of detectors into a third digital signal; said processing means is based on said first digital signal, said second digital signal, and said The three digital signals reconstruct a CT image of the object being inspected.
- a versatile spectrum static CT apparatus comprising: a transport mechanism carrying linear motion of an object under inspection; and a first scan stage comprising: a first distributed ray source comprising a plurality of ray sources Point, the plurality of ray source points are disposed on a plane perpendicular to a moving direction of the object to be inspected, at least partially surrounding the object to be inspected, and emit X-rays toward the object to be inspected;
- the first row of detectors includes a plurality of detecting units having a first energy response disposed on a first plane parallel to a plane of the first distributed ray source, receiving X-rays penetrating the object to be inspected;
- a second scanning stage along The moving direction of the object to be inspected is set in series with the first scanning level, and the second scanning stage comprises: a second distributed ray source comprising a plurality of ray source points, wherein the plurality of ray source points are disposed at a plane perpendicular to the direction
- the energy spectrum of the radiation generated by the first distributed radiation source is different from the energy spectrum of the radiation generated by the second distributed radiation source.
- a versatile spectrum static CT apparatus including: a transport mechanism that carries linear motion of an object under inspection; and a first scan stage that includes: a first distributed ray source including a plurality of ray sources Point, the plurality of ray source points are disposed on a plane perpendicular to a moving direction of the object to be inspected, at least Partially surrounding the object to be inspected and emitting X-rays toward the object to be inspected; the first row of detectors comprising a plurality of detecting units having a first energy response disposed in the first distributed ray source a first plane parallel to the plane receiving X-rays penetrating the object under inspection; a second row of detectors including a plurality of detector units having a second energy response disposed in the first distributed ray source Receiving X-rays penetrating the object to be inspected on a second plane parallel to the plane; a second scanning stage disposed in series with the first scanning stage along a direction of movement of
- the energy spectrum of the radiation generated by the first distributed radiation source is different from the energy spectrum of the radiation generated by the second distributed radiation source.
- the first scanning stage further includes a fifth row of detectors adjacent to the second row of detectors in a moving direction of the object to be inspected, the fifth row of detectors including a third type a plurality of detecting units of energy response disposed on a third plane parallel to a plane of the distributed ray source, receiving X-rays penetrating the object to be inspected;
- the second scanning stage further includes a sixth row of detectors adjacent to the fourth row of detectors in a direction of motion of the object under inspection, the sixth row of detectors including a third energy response a plurality of detecting units disposed on a fourth plane parallel to a plane of the distributed ray source, receiving X-rays penetrating the object to be inspected;
- the collecting device converts X-rays detected by the fifth and sixth rows of detectors into fifth and sixth Digital signal
- the processing device reconstructs a CT image of the object under inspection based on the first to sixth digital signals.
- the above-mentioned problems faced by applying the multi-energy spectrum analysis technique to the static CT are solved, so that accurate and complete multi-energy projection data can be quickly obtained without the rotation of the slip ring.
- the system can reconstruct the atomic number and electron density image of the tested substance, and the image quality is better, the contraband identification ability is stronger, and the cost is lower.
- FIG. 1 is a schematic diagram of a slip ring structure of a conventional CT device
- FIG. 2 is a schematic diagram of a slip ring structure of a conventional dual-energy CT device
- FIG. 3 is a structural block diagram of a CT device according to an embodiment of the present disclosure.
- FIG. 4A is a schematic structural diagram of a CT device according to an embodiment of the present disclosure.
- Figure 4B is a side elevational view of the scanning stage of the CT apparatus shown in Figure 4A;
- FIG. 5 is a schematic structural diagram of a CT apparatus according to another embodiment of the present disclosure.
- FIG. 6 is a schematic structural diagram of a CT apparatus according to still another embodiment of the present disclosure.
- the apparatus comprises a transport mechanism 32, a distributed ray source 31, a detection device 33, an acquisition device 34 and a processing device 35.
- the transport mechanism 32 carries a linear motion of the object under inspection.
- the distributed ray source 31 includes a plurality of ray source points disposed on a plane perpendicular to a moving direction of the object to be inspected, at least partially surrounding the object to be inspected, and issued toward the object to be inspected X-rays.
- each source point is specifically a carbon nanotube X-ray tube.
- the distributed ray source 31 is comprised of a plurality of distributed X-ray sources, the beam-out energy of each X-ray source can be set, and the beam-out sequence of the X-ray source can be set.
- the X-sources are arranged in one or more planes, and the X-rays on each plane are treated as a group.
- the same set of X-ray sources are set to the same beam-out energy, and different sets of X-ray sources are set to different beam-out energies.
- the X-ray source can be arranged as a continuous or discontinuous multi-segment line or arc, but the arrangement of each set of X-ray sources is identical, ensuring that there is no projection angle deviation between the multi-energy data.
- the detecting device 33 includes a first row of detectors and a second row of detectors adjacent to the first row of detectors in a direction of motion of the object to be inspected, the first row of detectors including a first type of energy a plurality of responsive detection units disposed on a first plane parallel to a plane of the distributed ray source, receiving X-rays penetrating the object under inspection, the second row of detectors including a second energy source The plurality of responsive detection units are disposed on a second plane parallel to the plane of the distributed ray source to receive X-rays that penetrate the object under inspection.
- each X-ray source is arranged in a plane corresponding to a plurality of rows of detectors, and the detector units of each row of detectors can be arranged as continuous or discontinuous multi-segment lines or arcs, and each row of detectors Parallel arrangement along the direction of motion of the substance to be examined avoids the problem of ray obliqueity caused by placement in the ray direction.
- Each row of detection units of the multi-row detector can detect different energy responses of the X-rays emitted by the group of X-rays by means of different detection materials or thicknesses or different filters of the detector front-end (X-rays) The energy range is from 0 to the set value of the outgoing energy).
- the first row of detectors and the second row of detectors has a filter.
- the first type of energy response primarily responds to low energy components in X-rays.
- the second energy response is primarily responsive to a high energy component in the X-ray, and the processing device reconstructs the high energy attenuation coefficient image and the low energy attenuation coefficient image of the object under test based on the first digital signal and the second digital signal. Since different sets of X-ray sources are set to different beam-out energies, multiple rows of detectors corresponding to two or more X-ray sources can detect more energy ranges and energy segments, resulting in more accurate and detailed pluripotency analysis results. .
- At least one of the first row of detectors and the second row of detectors has a filter.
- the collecting device 34 is connected to the detecting device 33, converts the X-rays detected by the first row of detectors into a first digital signal, and converts the X-rays detected by the second row of detectors into a second digital signal.
- the acquisition device 34 samples the electrical signals output by all of the detection units at high speed and converts them into digital signals for transmission to the processing device 35.
- the processing device 35 is coupled to the acquisition device 34 to reconstruct a CT image of the object under inspection based on the first digital signal and the second digital signal. For example, the processing device 35 reconstructs an atomic value and an electron density value of the object under inspection based on the first digital signal and the second digital signal.
- the baggage transport mechanism and the control device are responsible for transmitting the test substance through the imaging area surrounded by the distributed ray source, the detecting device and the collecting device, and controlling each X-ray source according to the set beam energy and output.
- the beam sequence works to control the multi-row detector and the data acquisition device to perform high-speed sampling according to the set time interval or the external trigger signal.
- the baggage transfer and control device can provide a position index or time index of the test substance for each set of samples, combined between several imaging surfaces. The distance or the time difference between the test object passing through several imaging planes enables the data processing device to extract the registered multi-energy projection data.
- the processing device 35 is responsible for reconstructing the three-dimensional atomic number image and the electron density image of the test substance from the multi-energy projection data.
- the high- and low-energy projection data acquired from the dual-energy detector is recorded as p 1 and p 2 .
- the data is pre-processed and corrected, such as background and gain correction, detector bad track correction, and so on.
- the base material decomposition method is used to perform dual energy decomposition on the fan beam projection data obtained after rearrangement, and decomposed into dual energy decomposition coefficients A 1 and A 2 under different base materials.
- the two coefficients are reconstructed by CT reconstruction algorithm respectively.
- the reconstruction results a 1 and a 2 are obtained .
- the distribution values of the atomic number Z and the electron density ⁇ e are solved according to the following formula:
- Z 1 and Z 2 are the atomic order values of the two base materials, respectively, and ⁇ e1 and ⁇ e2 are the electron density values of the two base materials, respectively.
- this method is also called a pre-processing algorithm, and can also be implemented by using a post-processing method, that is, the high-low-energy projection data is separately reconstructed by CT, and then The material information distribution image is calculated according to the reconstructed high and low energy attenuation coefficient image.
- This method usually has the advantages of simple and fast calculation.
- the post-processing reconstruction method can obtain higher precision.
- FIG. 4A is a schematic structural diagram of a CT apparatus according to an embodiment of the present disclosure.
- Figure 4B is a side elevational view of the scanning stage of the CT apparatus shown in Figure 4A.
- the multi-spectral static CT imaging system shown in this example uses a set of distributed X-ray sources A, and all X-ray sources of the distributed X-ray source A set the same beam-out energy, and The two rows of detectors corresponding to the distributed X-ray source A are distributed in parallel on two adjacent planes, namely a high energy detector B and a low energy detector C.
- FIG. 5 is a schematic structural diagram of a CT apparatus according to another embodiment of the present disclosure.
- the multi-spectral static CT imaging system shown in this example includes two scanning stages, the first scanning stage and the second scanning stage respectively using a distributed X-ray source A and a distributed X-ray source D.
- the arrangement of the X-sources of the distributed X-ray sources A and D is exactly the same, all the X-ray sources of the distributed X-ray source A set the same beam-out energy, and all the X-sources of the distributed X-ray source D set the same beam-out energy.
- the X-ray sources of the distributed X-sources A and D have different beam energies.
- the two rows of detectors B and E are distributed in parallel on two planes, corresponding to the distributed X-ray source A and the distributed X-ray source D, respectively.
- the transport mechanism 32 carries a linear motion of the object under inspection.
- the first scan stage includes a first distributed ray source and a first row of detectors.
- a first distributed ray source comprising a plurality of ray source points, the plurality of ray source points being disposed on a plane perpendicular to a moving direction of the object to be inspected, at least partially surrounding the object to be inspected, and being inspected toward the object
- the object emits X-rays.
- the first row of detectors includes a plurality of detection units having a first type of energy response disposed on a first plane parallel to a plane of the first distributed source of radiation to receive X-rays that penetrate the object under inspection.
- a second scan stage is disposed in series with the first scan stage along a direction of motion of the object under inspection, the second scan stage including a second distributed ray source and a second row of detectors.
- the second distributed ray source includes a plurality of ray source points disposed on a plane perpendicular to a moving direction of the object to be inspected, at least partially surrounding the object to be inspected, and facing the object to be inspected Generating an X-ray; a second row of detectors comprising a plurality of detector units having a second energy response disposed on a second plane parallel to a plane of the second distributed source of radiation X-rays of the object.
- the collecting device 34 is connected to the first row of detectors and the second row of detectors, and converts the X-rays detected by the first row of detectors into a first digital signal, and the second The X-rays detected by the row detector are converted into a second digital signal.
- the processing device 35 is coupled to the acquisition device 34 and reconstructs a CT image of the object under inspection based on the first digital signal and the second digital signal.
- FIG. 6 is a schematic structural diagram of a CT apparatus according to still another embodiment of the present disclosure.
- the multi-spectral static CT imaging system shown in this example includes two scanning stages, and the first scanning stage and the second scanning stage respectively use a distributed X-ray source A and a distributed X-ray source D.
- All X-ray sources of distributed X-ray source A set the same beam-out energy
- all X-sources of distributed X-ray source D set the same beam-out energy
- the arrangement of the X-sources of the distributed X-sources A and D is identical.
- the four rows of detectors B, C, E, and F are distributed in parallel on four planes.
- the two rows of detectors B and C corresponding to the distributed X-ray source A are in close proximity and have different energy responses for detecting the X-rays emitted by the distributed X-ray source A.
- the two rows of detectors E and F corresponding to the distributed X-ray source D are in close proximity and have different energy responses for detecting the X-rays emitted by the distributed X-ray source D.
- the transport mechanism 32 carries a linear motion of the object under inspection.
- the first scan stage includes a first distributed ray source, a first row of detectors, and a second row of detectors.
- the first distributed ray source includes a plurality of ray source points disposed on a plane perpendicular to a moving direction of the object to be inspected, at least partially surrounding the object to be inspected, and facing the object to be inspected X-rays are emitted.
- a first row of detectors comprising a plurality of detection units having a first energy response disposed on a first plane parallel to a plane of the first distributed ray source, receiving X-rays penetrating the object under inspection .
- a second row of detectors comprising a plurality of detection units having a second energy response disposed on a second plane parallel to a plane of the first distributed source of radiation, receiving X-rays penetrating the object under inspection ;
- a second scanning stage is disposed in series with the first scanning stage along a direction of motion of the object to be inspected, the second scanning stage including a second distributed ray source, a third row of detectors, and a fourth row of detectors.
- the second distributed ray source includes a plurality of ray source points, and the plurality of ray source points are disposed at the object to be inspected
- the plane perpendicular to the direction of motion of the body at least partially surrounds the object to be inspected and emits X-rays toward the object to be inspected.
- a third row of detectors comprising a plurality of detection units having a first energy response disposed on a third plane parallel to a plane of the second distributed radiation source, receiving X-rays penetrating the object under inspection .
- a fourth row of detectors comprising a plurality of detection units having a second energy response disposed on a fourth plane parallel to a plane of the second distributed ray source, receiving X-rays penetrating the object under inspection .
- the collecting device 34 is connected to the first row of detectors, the second row of detectors, the third row of detectors, and the fourth row of detectors, and the X of the first row of detectors is detected Converting the ray into a first digital signal, converting the X-rays detected by the second row of detectors into a second digital signal, converting the X-rays detected by the third row of detectors into a third digital signal, The X-rays detected by the four rows of detectors are converted into fourth digital signals.
- the processing device 35 is coupled to the acquisition device 34 and reconstructs a CT image of the object under inspection based on one of the first digital signal, the second digital signal, the third digital signal, and the fourth digital signal.
- each scan stage of the CT device includes two rows of detector arrays, it will be appreciated by those skilled in the art that a greater number of detector arrays can be used.
- a parallel third row of detectors is included in the first scan stage and a fourth row of detectors is included in the second scan.
- the ray energy spectrum of the first distributed ray source may be the same as the ray energy spectrum of the second distributed ray source or may be set to be different or partially overlapping according to different needs.
- the multi-spectral static CT imaging system proposed by the above embodiment uses a distributed X-ray source to illuminate baggage articles from different angles, thereby eliminating the high-speed rotating slip ring in the existing CT system, and has high safety reliability and reduced
- the system cost increases the scanning speed.
- multi-energy spectrum analysis technology it can obtain the atomic number and electron density at any position inside the baggage item, thus providing more and more intuitive information for subsequent applications such as checking for danger and checking the private. It is of great significance to quickly and accurately check for prohibited items such as explosives, flammable materials and drugs.
- the solution of this embodiment is not only to combine the static CT technology with the pluripotency spectrum analysis technology, but also to design and arrange the distributed X-ray source and the multi-row detector in the system, thereby avoiding the slip ring-based CT system.
- the multi-energy spectrum implementation method has the ray oblique problem in the static CT system and the projection angle deviation between the multi-energy data, thereby ensuring the resolution of the CT reconstructed image and the accuracy of the energy spectrum analysis result.
- aspects of the embodiments disclosed herein may be implemented in an integrated circuit as a whole or in part, as one or more of one or more computers running on one or more computers.
- a computer program eg, implemented as one or more programs running on one or more computer systems
- implemented as one or more programs running on one or more processors eg, implemented as one or One or more programs running on a plurality of microprocessors, implemented as firmware, or substantially in any combination of the above, and those skilled in the art, in accordance with the present disclosure, will be provided with design circuitry and/or write software and / or firmware code capabilities.
- signal bearing media include, but are not limited to, recordable media such as floppy disks, hard drives, compact disks (CDs), digital versatile disks (DVDs), digital tapes, computer memories, and the like; and transmission-type media such as digital and / or analog communication media (eg, fiber optic cable, waveguide, wired communication link, wireless communication link, etc.).
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Abstract
一种多能谱静态CT设备,包括多点分布式的射线发生装置(31),多排探测器(B、C、E、F)及数据采集装置(34),行李传送及控制装置(32)以及多能量投影数据处理装置(35)。将静态CT扫描模式与多能谱分析技术相结合,既保留静态CT原有优点,如扫描速度快、机械结构简单、节省滑环和探测器成本等,又可以实现对物质成分的识别,对于安全检查、海关缉私等场合都具有很高的实用价值。
Description
本公开涉及辐射成像检测技术领域,尤其涉及多能谱静态CT设备。
CT技术由于能够消除物体重叠的影响,在安全检查等场合中发挥了重要作用。传统的CT采用滑环装置通过X光源和探测器的旋转来获取不同角度上的投影数据,通过重建方法来获取断层图像,从而获得被检测行李物品的内部信息。多能谱分析是指利用某种材料对不同能量的X射线吸收性能上的差异来分辨该材料。CT技术配合多能谱分析技术,使得目前的行李物品检查设备可以对被检物质内部任意位置的原子序数和电子密度进行重建,实现物质种类的识别,在***物、毒品等检测中起到了较好的效果。
但是,由于现有的CT装置在数据采集过程中通常采用滑环旋转,不但扫描速度有限、体积庞大,而且机械加工精度要求高,成本较高,限制了其在实际中的广泛应用。近些年,碳纳米管X光管技术进入了实用领域。与传统光源不同,它无须利用高温来产生射线,而是根据碳纳米管尖端放电原理产生阴极射线,打靶产生X光。其优点是可以快速开启和关闭,且体积更小。把这种X光源排布成环状,进行不同角度下对物体的照射,就可以制成无需旋转的“静态CT”,大大提高了射线成像的速度,同时由于省去了滑环的结构,节省了成本,对于安全检查等领域具有十分重要的意义。
经过对文献及专利的查询,目前尚未发现在辐射成像***中综合应用静态CT技术与多能谱分析技术的报告。现有静态CT***均为单能***,仅能重建出被检物质内部的线性衰减系数,极大限制了其识别能力。而如果采用多能谱技术,实现多能谱的静态CT***则面临着一些实际困难。一方面,现有的CT装置为了实现多能谱分析常采用单一能量X光源加多能探测器,将探测不同能量X射线的探测器前后放置,射线先进入探测较低能量X射线的探测器,经过能谱整形后进入探测较高能量X射线的探测器。图1示意了滑环CT采用单一能量X光源110加前后放置的双能探测器120和130实现能谱分析的方法,光源和探测器可以随滑环旋转,探测器不需要覆盖很大角度,任意一条射线穿过的低能探测器120和高能探测器130都是一一对应的,易于进行准确的多能谱分析。而静态CT取消了滑环结构采用分
布式光源210,探测器220和230需要覆盖很大的角度范围甚至排布成圆环的形式,如图2所示。这样如果采用前后放置的多能探测器220和230将会导致射线斜射问题,且不同角度的射线斜射程度各不相同。斜射不仅带来了高低能数据配准的困难,还会加剧相邻探测器之间的串扰,造成重建图像的分辨率下降。
另一方面,现有CT实现多能谱分析的也常使用另一类方法,即采用多能X光源加单能探测器,通过滑环旋转过程中X光源在多个能量之间高速切换来获取不同能量下的扫描,然而这种方法也存在固有的不足。X光源在多个能量之间切换时滑环在高速旋转,导致高低能数据之间存在着投影角度的偏差,当X光源能量切换的频率较高时,这个偏差一般较小可以忽略,而如果把这种方法应用到静态CT,则需要将多点源中相邻的X光源设置为不同的能量,出于成本、工艺等因素的考虑X光源的数量不可能非常多,因此高低能数据之间的投影角度偏差将无法忽略,影响了多能谱分析的精度。
公开内容
针对现有技术中的一个或多个问题,提出了一种多能谱静态CT设备。
在本公开的一个方面,提出了一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;探测装置,包括第一排探测器和在所述被检查物体的运动方向上与所述第一排探测器相邻的第二排探测器,所述第一排探测器包括具有第一种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线,所述第二排探测器包括具有第二种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;采集装置,与所述探测装置连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。
优选地,所述第一排探测器和所述第二排探测器中的至少之一具有滤波片。
优选地,每个射线源点具体为碳纳米管X射线管。
优选地,第一种能量响应主要响应X射线中的低能成分,第二种能量响应主要响应X射线中的高能成分,并且所述处理装置基于所述第一数字信号和所述第
二数字信号重建所述被检查物体的高能衰减系数图像和低能衰减系数图像。
优选地,所述处理装置基于所述第一数字信号和第二数字信号重建所述被检查物体的原子序数值和电子密度值。
优选地,所述探测装置还包括在所述被检查物体的运动方向上与所述第二排探测器相邻的第三排探测器,所述第三排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线;所述采集装置将所述第三排探测器探测的X射线转换为第三数字信号,将所述第三排探测器探测的X射线转换为第三数字信号;所述处理装置基于所述第一数字信号、所述第二数字信号和所述第三数字信号重建被检查物体的CT图像。
在本公开的另一方面,提出了一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;第一扫描级,包括:第一分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第一排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线;第二扫描级,沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括:第二分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;采集装置,与所述第一排探测器和所述第二排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。
优选地,所述第一分布式射线源产生的射线的能谱与第二分布式射线源产生的射线的能谱不同。
在本公开的再一方面,提出了一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;第一扫描级,包括:第一分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少
部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第一排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线;第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;第二扫描级,沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括:第二分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第三排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线;第四排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第四平面上,接收穿透所述被检查物体的X射线;采集装置,与所述第一排探测器、所述第二排探测器、所述第三排探测器器、和所述第四排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号,将所述第三排探测器探测的X射线转换为第三数字信号,将所述第四排探测器探测的X射线转换为第四数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号、所述第二数字信号、所述第三数字信号、和所述第四数字信号之一重建被检查物体的CT图像。
优选地,所述第一分布式射线源产生的射线的能谱与第二分布式射线源产生的射线的能谱不同。
优选地,所述第一扫描级还包括在所述被检查物体的运动方向上与所述第二排探测器相邻的第五排探测器,所述第五排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线;
所述第二扫描级还包括在所述被检查物体的运动方向上与所述第四排探测器相邻的第六排探测器,所述第六排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第四平面上,接收穿透所述被检查物体的X射线;
所述采集装置将所述第五和第六排探测器探测的X射线转换为第五和第六
数字信号;
所述处理装置基于所述第一至第六数字信号重建被检查物体的CT图像。
根据上述的多能谱静态CT***,解决了将多能谱分析技术应用到静态CT所面临的上述问题,从而不需要滑环旋转即可快速得到准确完备的多能量投影数据。此外,该***能重建出被检物质的原子序数和电子密度图像,图像质量更好、违禁品识别能力更强、成本更低。
为了更好的理解本公开,将根据以下附图对本公开的实施例进行描述:
图1为现有的CT设备的滑环结构的示意图;
图2为现有的双能CT设备的滑环结构的示意图;
图3为根据本公开一实施例的CT设备的结构框图;
图4A为根据本公开一实施例的CT设备的结构示意图;
图4B为如图4A所示的CT设备中扫描级的侧视图;
图5为根据本公开另一实施例的CT设备的结构示意图;
图6为根据本公开又一实施例的CT设备的结构示意图。
附图没有对实施例的所有结构进行显示。贯穿所有附图相同的附图标记表示相同或相似的部件或特征。
下面将详细描述本公开的具体实施例,应当注意,这里描述的实施例只用于举例说明,并不用于限制本公开。在以下描述中,为了提供对本公开的透彻理解,阐述了大量特定细节。然而,对于本领域普通技术人员显而易见的是:不必采用这些特定细节来实行本公开。在其他实例中,为了避免混淆本公开,未具体描述公知的电路、材料或方法。
在整个说明书中,对“一个实施例”、“实施例”、“一个示例”或“示例”的提及意味着:结合该实施例或示例描述的特定特征、结构或特性被包含在本公开至少一个实施例中。因此,在整个说明书的各个地方出现的短语“在一个实施例中”、“在实施例中”、“一个示例”或“示例”不一定都指同一实施例或示例。此外,可以以任何适当的组合和/或子组合将特定的特征、结构或特性组合在一个或多个实施例或示例中。此外,本领域普通技术人员应当理解,在此提供的附图都是为了说明的目的,并且附图不一定是按比例绘制的。应当理解,当称元件“耦接到”或“连
接到”另一元件时,它可以是直接耦接或耦接到另一元件或者可以存在中间元件。相反,当称元件“直接耦接到”或“直接连接到”另一元件时,不存在中间元件。相同的附图标记指示相同的元件。这里使用的术语“和/或”包括一个或多个相关列出的项目的任何和所有组合。
为了解决多能谱静态CT***的上述问题,例如不需要滑环旋转即可快速得到准确完备的多能量投影数据,本公开的实施例提出了一种多能谱静态CT设备,如图3所示。该设备包括:传送机构32、分布式射线源31、探测装置33、采集装置34和处理装置35。传送机构32承载被检查物体直线运动。
分布式射线源31包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线。例如,每个射线源点具体为碳纳米管X射线管。
在一些实施例中,分布式射线源31由多个分布式的X光源组成,每个X光源的出束能量可以设定,X光源的出束顺序可以设定。X光源排布在一个或多个平面上,每个平面上的X光源视为一组。同组的X光源设定为相同的出束能量,不同组的X光源设定为不同的出束能量。X光源可以排布为连续或不连续的多段直线或弧线,但每组X光源的排布是完全相同的,保证多能量数据之间没有投影角度偏差。
探测装置33包括第一排探测器和在所述被检查物体的运动方向上与所述第一排探测器相邻的第二排探测器,所述第一排探测器包括具有第一种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线,所述第二排探测器包括具有第二种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线。
在一些实施例中,每一个X光源排布的平面都对应一组多排探测器,每一排探测器的探测单元可以排布为连续或不连续的多段直线或弧线,探测器各排沿着被检物质的运动方向平行布置,避免了沿射线方向前后放置所导致的射线斜射问题。多排探测器的每一排探测单元可以借助于不同的探测材料或厚度或者探测器前挡不同滤波片的方式,实现对该组X光源所发射的X射线的不同能量响应的探测(X射线能量范围是0到出束能量的设定值)。例如,第一排探测器和第二排探测器中的至少之一具有滤波片。第一种能量响应主要响应X射线中的低能成分,
第二种能量响应主要响应X射线中的高能成分,并且所述处理装置基于所述第一数字信号和所述第二数字信号重建所述被检查物体的高能衰减系数图像和低能衰减系数图像。由于不同组的X光源被设定为不同的出束能量,对应2组及以上X光源的多排探测器就能够探测更多的能量范围和能量段,获得更加准确精细的多能谱分析结果。
在一些实施例中,第一排探测器和第二排探测器中的至少之一具有滤波片。
采集装置34与所述探测装置33连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号。采集装置34对所有探测单元输出的电信号进行高速采样并转换为数字信号,传送到处理装置35。
处理装置35与所述采集装置34连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。例如,处理装置35基于所述第一数字信号和第二数字信号重建所述被检查物体的原子序数值和电子密度值。
此外,在一些实施例中,行李传送机构及控制装置负责传送被检物质通过由分布式射线源、探测装置及采集装置包围的成像区域,控制每个X光源按设定的出束能量和出束顺序工作,控制多排探测器和数据采集装置依据设定的时间间隔或外部触发信号进行高速采样。
使用2组及以上X光源的***需要额外处理多个成像面的数据配准问题,行李传送及控制装置可以为每组采样提供被检物质的位置索引或时间索引,结合几个成像面之间的距离或者被检物质通过几个成像面的时间差,数据处理装置就能够提取出配准的多能量投影数据。
处理装置35负责从多能量投影数据中重建出被检物质的三维原子序数图像和电子密度图像。
以双能投影数据为例,从双能探测器获取扫描的高低能投影数据记作p1和p2。先对数据进行预处理和校正,比如本底和增益校正、探测器坏道校正等。然后采用基材料分解方法对重排后得到的扇束投影数据进行双能分解,分解到不同基材料下的双能分解系数A1和A2,对这两个系数分别使用CT重建算法进行重建,得到重建结果a1和a2。之后,根据如下公式求解出原子序数Z和电子密度ρe的分布值:
ρe=a1ρe1+a2ρe2 (2)
该公式中,Z1和Z2分别为两种基材料的原子序数值,ρe1和ρe2分别为两种基材料的电子密度值。上述双能重建方法中先将投影数据分解,再进行重建,因此也称这类方法为前处理算法,此外也可以使用后处理方法来实现,即先将高低能投影数据分别进行CT重建,再根据重建得到的高低能衰减系数图像计算材料信息分布图像,这种方法通常具备计算简单快速的优点,在扫描对象材料变化范围较小时,后处理重建方法可以得到较高的精度。
图4A为根据本公开一实施例的CT设备的结构示意图。图4B为如图4A所示的CT设备中扫描级的侧视图。
如图4A和图4B所示,该例所示的多能谱静态CT成像***使用了1组分布式的X光源A,分布式X光源A的所有X光源设定相同的出束能量,与分布式X光源A对应的2排探测器平行分布在2个紧邻的平面上,分别是高能量探测器B和低能量探测器C。
图5为根据本公开另一实施例的CT设备的结构示意图。如图5所示,该例所示的多能谱静态CT成像***包括两个扫描级,第一扫描级和第二扫描级分别使用分布式的X光源A和分布式X光源D。分布式X光源A和D的X光源的排布完全相同,分布式X光源A的所有X光源设定相同的出束能量,分布式X光源D的所有X光源设定相同的出束能量,分布式X光源A和D的X光源出束能量不同。2排探测器B和E平行分布在2个平面上,分别与分布式X光源A和分布式X光源D对应。
在该实施例中,传送机构32承载被检查物体直线运动。第一扫描级包括第一分布式射线源和第一排探测器。第一分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线。第一排探测器包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线。
第二扫描级沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括第二分布式射线源和第二排探测器。
第二分布式射线源包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线。
该实施例中,采集装置34与所述第一排探测器和所述第二排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号。处理装置35与采集装置34连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。
图6为根据本公开又一实施例的CT设备的结构示意图。如图6所示,该例所示的多能谱静态CT成像***包含两个扫描级,第一扫描级和第二扫描级分别使用了分布式的X光源A和分布式X光源D。分布式X光源A的所有X光源设定相同的出束能量,分布式X光源D的所有X光源设定相同的出束能量,并保持分布式X光源A和D的X光源出束能量不同,分布式X光源A和D的X光源的排布完全相同。4排探测器B、C、E、F平行分布在4个平面上。与分布式X光源A对应的2排探测器B和C紧邻,且具有不同能量响应,用于探测分布式X光源A所发射的X射线。与分布式X光源D对应的2排探测器E和F紧邻,且具有不同能量响应,用于探测分布式X光源D所发射的X射线。
在该实施例中,传送机构32承载被检查物体直线运动。第一扫描级包括第一分布式射线源、第一排探测器和第二排探测器。
第一分布式射线源包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线。第一排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线。第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;
第二扫描级沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括第二分布式射线源、第三排探测器和第四排探测器。
第二分布式射线源包括多个射线源点,所述多个射线源点设置在与被检查物
体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线。第三排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线。第四排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第四平面上,接收穿透所述被检查物体的X射线。
采集装置34与所述第一排探测器、所述第二排探测器、所述第三排探测器器、和所述第四排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号,将所述第三排探测器探测的X射线转换为第三数字信号,将所述第四排探测器探测的X射线转换为第四数字信号。
处理装置35与所述采集装置34连接,基于所述第一数字信号、所述第二数字信号、所述第三数字信号、和所述第四数字信号之一重建被检查物体的CT图像。
虽然在上述的实施例中,CT设备的每一扫描级都包括两排探测器阵列,但是本领域的技术人员应该想到,可以使用更多数目的探测器阵列。同样,在第一扫描级中包括平行的第三排探测器,在第二扫描机中包括第四排探测器。此外,在一些实施例中,第一分布式射线源的射线能谱与第二分布式射线源的射线能谱可以相同也可以根据不同的需要设置为不同,或者部分重叠。
上述实施例所提出的多能谱静态CT成像***使用分布式的X光源从不同角度对行李物品进行照射,省去了现有CT***中的高速旋转滑环,安全性可靠性高,降低了***成本,提高了扫描速度,同时结合多能谱分析技术,能够获取行李物品内部任意位置的原子序数和电子密度,从而为查危、查私等后续应用提供了更多更直观的信息,对快速准确的检查***物、易燃物、毒品等违禁物品具有十分重要的意义。
该实施例的方案不仅在于将静态CT技术与多能谱分析技术相结合,更在于对***中分布式X光源以及多排探测器的巧妙设计和排布,从而避免了基于滑环的CT***的多能谱实现方法在静态CT***中出现的射线斜射问题以及多能量数据之间的投影角度偏差问题,从而保证了CT重建图像的分辨率和能谱分析结果的精度。
以上的详细描述通过使用方框图、流程图和/或示例,已经阐述了多能谱静态CT设备的众多实施例。在这种方框图、流程图和/或示例包含一个或多个功能和/或操作的情况下,本领域技术人员应理解,这种方框图、流程图或示例中的每一功能和/或操作可以通过各种硬件、软件、固件或实质上它们的任意组合来单独和/或共同实现。在一个实施例中,本公开的实施例所述主题的若干部分可以通过专用集成电路(ASIC)、现场可编程门阵列(FPGA)、数字信号处理器(DSP)、或其他集成格式来实现。然而,本领域技术人员应认识到,这里所公开的实施例的一些方面在整体上或部分地可以等同地实现在集成电路中,实现为在一台或多台计算机上运行的一个或多个计算机程序(例如,实现为在一台或多台计算机***上运行的一个或多个程序),实现为在一个或多个处理器上运行的一个或多个程序(例如,实现为在一个或多个微处理器上运行的一个或多个程序),实现为固件,或者实质上实现为上述方式的任意组合,并且本领域技术人员根据本公开,将具备设计电路和/或写入软件和/或固件代码的能力。此外,本领域技术人员将认识到,本公开所述主题的机制能够作为多种形式的程序产品进行分发,并且无论实际用来执行分发的信号承载介质的具体类型如何,本公开所述主题的示例性实施例均适用。信号承载介质的示例包括但不限于:可记录型介质,如软盘、硬盘驱动器、紧致盘(CD)、数字通用盘(DVD)、数字磁带、计算机存储器等;以及传输型介质,如数字和/或模拟通信介质(例如,光纤光缆、波导、有线通信链路、无线通信链路等)。
虽然已参照几个典型实施例描述了本公开,但应当理解,所用的术语是说明和示例性、而非限制性的术语。由于本公开能够以多种形式具体实施而不脱离公开的精神或实质,所以应当理解,上述实施例不限于任何前述的细节,而应在随附权利要求所限定的精神和范围内广泛地解释,因此落入权利要求或其等效范围内的全部变化和改型都应为随附权利要求所涵盖。
Claims (11)
- 一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;探测装置,包括第一排探测器和在所述被检查物体的运动方向上与所述第一排探测器相邻的第二排探测器,所述第一排探测器包括具有第一种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线,所述第二排探测器包括具有第二种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;采集装置,与所述探测装置连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。
- 如权利要求1所述的CT设备,其中所述第一排探测器和所述第二排探测器中的至少之一具有滤波片。
- 如权利要求1所述的CT设备,其中每个射线源点具体为碳纳米管X射线管。
- 如权利要求1所述的CT设备,其中第一种能量响应主要响应X射线中的低能成分,第二种能量响应主要响应X射线中的高能成分,并且所述处理装置基于所述第一数字信号和所述第二数字信号重建所述被检查物体的高能衰减系数图像和低能衰减系数图像。
- 如权利要求4所述的CT设备,其中所述处理装置基于所述第一数字信号和第二数字信号重建所述被检查物体的原子序数值和电子密度值。
- 如权利要求1所述的CT设备,其中所述探测装置还包括在所述被检查物体的运动方向上与所述第二排探测器相邻的第三排探测器,所述第三排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行 的第三平面上,接收穿透所述被检查物体的X射线;所述采集装置将所述第三排探测器探测的X射线转换为第三数字信号,将所述第三排探测器探测的X射线转换为第三数字信号;所述处理装置基于所述第一数字信号、所述第二数字信号和所述第三数字信号重建被检查物体的CT图像。
- 一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;第一扫描级,包括:第一分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第一排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线;第二扫描级,沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括:第二分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;采集装置,与所述第一排探测器和所述第二排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号和所述第二数字信号重建被检查物体的CT图像。
- 如权利要求7所述的CT设备,其中所述第一分布式射线源产生的射线的能谱与第二分布式射线源产生的射线的能谱不同。
- 一种多能谱静态CT设备,包括:传送机构,承载被检查物体直线运动;第一扫描级,包括:第一分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第一排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第一平面上,接收穿透所述被检查物体的X射线;第二排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第一分布式射线源的平面平行的第二平面上,接收穿透所述被检查物体的X射线;第二扫描级,沿着所述被检查物体的运动方向与所述第一扫描级串联设置,所述第二扫描级包括:第二分布式射线源,包括多个射线源点,所述多个射线源点设置在与被检查物体的运动方向垂直的平面上,至少部分环绕所述被检查物体,并且向着所述被检查物体发出X射线;第三排探测器,包括具有第一种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线;第四排探测器,包括具有第二种能量响应的多个探测单元,设置在与所述第二分布式射线源的平面平行的第四平面上,接收穿透所述被检查物体的X射线;采集装置,与所述第一排探测器、所述第二排探测器、所述第三排探测器器、和所述第四排探测器连接,将所述第一排探测器探测的X射线转换为第一数字信号,将所述第二排探测器探测的X射线转换为第二数字信号,将所述第三排探测器探测的X射线转换为第三数字信号,将所述第四排探测器探测的X射线转换为第四数字信号;处理装置,与所述采集装置连接,基于所述第一数字信号、所述第二数字信号、所述第三数字信号、和所述第四数字信号之一重建被检查物体的CT图像。
- 如权利要求9所述的CT设备,其中所述第一分布式射线源产生的射线 的能谱与第二分布式射线源产生的射线的能谱不同。
- 如权利要求9所述的CT设备,其中所述第一扫描级还包括在所述被检查物体的运动方向上与所述第二排探测器相邻的第五排探测器,所述第五排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第三平面上,接收穿透所述被检查物体的X射线;所述第二扫描级还包括在所述被检查物体的运动方向上与所述第四排探测器相邻的第六排探测器,所述第六排探测器包括具有第三种能量响应的多个探测单元,设置在与所述分布式射线源的平面平行的第四平面上,接收穿透所述被检查物体的X射线;所述采集装置将所述第五和第六排探测器探测的X射线转换为第五和第六数字信号;所述处理装置基于所述第一至第六数字信号重建被检查物体的CT图像。
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