Source: https://patents.justia.com/patent/7724869
Timestamp: 2019-05-22 04:36:25
Document Index: 584185443

Matched Legal Cases: ['art 105', 'art 105', 'arts 1', 'arts 2', 'art 2', 'art 2', 'art 106', 'arts 3', 'art 3', 'art 3', 'art 106', 'arts 1', 'art 1', 'art 1', 'art 2', 'art 2', 'art 2', 'arts 2', 'art 2', 'art 3', 'art 2', 'art 2', 'art 2', 'art 2', 'art 106', 'arts 1', 'art 2', 'arts 3', 'art 3', 'arts 4', 'art 4']

US Patent for Detector array and device using the same Patent (Patent # 7,724,869 issued May 25, 2010) - Justia Patents Search
Justia Patents Inspection Of Closed ContainerUS Patent for Detector array and device using the same Patent (Patent # 7,724,869)
Apr 23, 2007 - Tsinghua University
Method and device for controlling active distribution network
Terahertz imaging system using tunable fishnet metamaterials
As shown in FIG. 1, the detector array including the first linear array 104a and the second linear array 104b is used to collect the dual-energy rays generated alternately by a radiation source. The radiation source 100 can alternately generate radiations such as X-rays. The synchronization control part 105 provides a synchronization signal 110 for the radiation source 100 and the first and second linear arrays 104a and 104b to make the radiation source 100 alternately generate high- and low-energy-level rays at the timing of the synchronization signal 110.
A fan-shaped planar radiation is obtained after the rays 102 generated by the radiation source 100 pass through the collimator 101. As shown in FIG. 1, the inspected object 103 moves at a fixed speed in a fixed direction perpendicular to the radiation plane. The penetrating radiation after the interaction between the planar radiation and the inspected object 103 is detected by the first and second linear arrays 104a and 104b. Here, the first and second linear arrays 104a and 104b are arranged parallel to each other, and based on the synchronization signal from the synchronization control part 105, adjust the parameters of the collecting circuits to perform simultaneous collecting. However, this isn't necessary.
As shown in FIG. 2, on the basis of the timing 203, the radiation source 100 alternately generates rays 102H and 102L having high and low energy levels, which are alternately emitted at a fixed frequency with the time intervals t between the emission of two ray beams are equal. The object 103 moves at a fixed speed along certain direction. It is assumed that the radiation source 100 emits a high-energy ray 102H, which is collimated and then interacts with the parts 1 and 2 of the inspected object 103. The penetrating ray is collected and buffered by the first and second linear arrays 104a and 104b, respectively, and the detection values are referred as 102H-1A and 102H-2B.
Then, the radiation source 100 emits a low-energy ray 102L when the time t has elapsed. At this time, the inspected object 103 has moved forward by a distance of one pixel, i.e., V*t. The low-energy ray 102L penetrate through the parts 2 and 3 of the inspected object 103, and is subsequently collected and buffered by the first and second linear arrays 104a and 104b, respectively, with the detection values being referred as 102L-2A and 102L-3B. The processing module of the detector array pairs the previously buffered detection value 102H-2B, which is collected after the high-energy ray 102H interacts with the part 2 of the inspected object 103, and the newly buffered detection value 102L-2A, which is collected after the low-energy ray 102L interacts with the part 2 of the inspected object 103, and outputs the pair to the image processing and material identification part 106.
Next, on the basis of the timing 203, the radiation source 100 generate a high-energy ray 102H again, while the inspected object 103 moves further by a distance of one pixel V*t. Therefore, the high-energy ray 102H interacts with the parts 3 and 4 of the inspected object 103. After such interaction, the detection values are collected respectively by the first and second linear arrays 104a and 104b, and referred as 102H-3A and 102H-4B. Subsequently, the processing module of the detector array pairs the previously buffered detection value 102L-3B, which is collected after the low-energy ray 102L interacts with the part 3 of the inspected object 103, and the newly collected detection value 102H-3A, which is collected after the high-energy ray 102H interacts with the part 3 of the inspected object 103, and outputs the pair to the image processing and material discrimination part 106. In this way, as the inspected object 103 moves, the signal detection is performed after the high- and low-energy rays interact with the same part of the inspected object 103.
Since the paralleled first and second linear arrays 104a and 104b are utilized, the first ray, which is an approximate narrow beam of high energy and first generated by the radiation source 100, can be collected by the first and second linear arrays 104a and 104b after the interaction with the parts 1 and 2 of the inspected object 103. The first linear array 104a detects the first ray penetrating through the part 1 of the inspected object 103 and outputs the first detection value for the part 1, and the second linear array 104b detects the first ray penetrating through the part 2 of the inspected object 103 and outputs the first detection value for the part 2. Immediately following is that the radiation source 100 emits the second ray of a low energy level. Since the inspected object 103 has move forward by a distance of one pixel, the second ray will interact with the part 2 and 3 of the inspected object 103. The first and second linear arrays 104a and 104b detect the signals for the parts 2 and 3 penetrated through by the second ray, and output the second detection value for the part 2 and the first detection value for the part 3, respectively. Accordingly, the first and second detection values for the part 2 are the values outputted after the first and second rays penetrate through the part 2 of the inspected object 103, respectively. Thus, the effective atomic number in the part 2 of the inspected object 103 can be determined based on the first and second detection values for this part, thereby determining the material property of the part 2.
Here, as shown in FIG. 3(A), the two linear arrays 104a and 104b each comprising a plurality of detector elements and they can be formed of two closely-arranged scintillators, such as CdWO4 and Csl. The first and second linear arrays 104a and 104b can be combined into a whole. The two scintillators of each row are fixed and connected to the processing module 305. After detecting signals, the two crystals simultaneously output the signals 302A and 302B, which are buffered and process in the processing module 305. When the detectors have collected the signals for the high- and low-energy rays upon two adjacent pulses, the processing module 305 matches the signals for the high- and low-energy rays and outputs the high- and low-energy detection values corresponding to the same part of the inspected object to the image processing and material discrimination part 106. As an alternative aspect, the two linear arrays 104a and 104b can independently output the signals 301A and 301B to their own processing modules (not shown), respectively. Every time the detector array collects the signals after the high- or low-energy ray penetrates through the inspected object, the signals are outputted to the processing module 305 so as to pair the detection values for the high- and low-energy rays, thereby obtaining the high- and low-energy detection values for each part of the inspected object 103. As an alternative aspect, each detector element of the two linear arrays can be formed of a gas detector.
Furthermore, the distance d between the first and second linear arrays 104a and 104b is adjustable as shown FIG. 3(B). Here, the distance d is determined by the moving speed V of the inspected object 103 and the time interval t between the generation of high- and low-energy rays by the radiation source, i.e., d=V*t. That is, the distance between the first and second linear arrays is adjusted based on the moving speed of the inspected object and the time interval between the generation of high- and low-energy rays by the radiation source, thereby meeting the need for the adjacent high- and low-energy rays to penetrate through the same part of the inspected object.
As shown in FIG. 4, the present embodiment differs from the previous embodiment in that the detector array comprises three linear arrays 104a, 104b and 104c corresponding to three rays 102H, 102M and 102L.
As shown in FIG. 4, on the basis of the timing 203, the radiation source 100 alternately generates rays 102H, 102M and 102L having high, medium and low energy levels, which are alternately emitted at a fixed frequency with the time intervals t between the emission of two ray beams are equal. The object 103 moves at a fixed speed along certain direction. It is assumed that the radiation source 100 emits a high-energy ray 102H, which is collimated and then interacts with the parts 1, 2 and 3 of the inspected object 103. The penetrating ray is collected and buffered by the first, second, and third linear arrays 104a, 104b and 104c, respectively, and the detection values are referred as 102H-1A, 102H-2B and 102H-3C.
Then, the radiation source 100 emits a medium-energy ray 102M when the time t has elapsed. At this time, the inspected object 103 has moved forward by a distance of one pixel, i.e., V*t. The medium-energy ray 102M penetrate through the part 2, 3 and 4 of the inspected object 103, and is subsequently collected and buffered by the first, second and third linear arrays 104a, 104b and 104c, respectively, with the detection values being referred as 102M-2A, 102M-3B and 102M-4C.
Then, the radiation source 100 emits a low-energy ray 102L when the time t has elapsed. At this time, the inspected object 103 has moved forward by a distance of one pixel, i.e., V*t. The low-energy ray 102L penetrate through the parts 3, 4 and 5 of the inspected object 103, and is subsequently collected and buffered by the first, second and third linear arrays 104a, 104b and 104c, respectively, with the detection values being referred as 102L-3A, 102L4B and 102L-5C. Thus, the transmission values of part 3 under three energy levels can be obtained, which are referred as 102H-3C, 102M-3B and 102L-3A.
Next, on the basis of the timing 203, the radiation source 100 generate a high-energy ray 102H again, while the inspected object 103 moves further by a distance of one pixel V*t. Therefore, the high-energy ray 102H interacts with the parts 4, 5 and 6 of the inspected object 103. After such interaction, the detection values are collected respectively by the first, second and third linear arrays 104a, 104b and 104c, and referred as 102H-4A, 102H-5B and 102H-6C. Subsequently, the transmission values of part 4 under three energy levels can be obtained, which are referred as 102H4A, 102M-4C and 102L-4B.
a detector array comprising: a first linear array for detecting a first x-ray and a second x-ray which penetrate through a first plurality of parts of an object under inspection to acquire first values and second values for the first plurality of parts, wherein the second x-ray and the first x-ray are alternately emitted from the radiation source; and a second linear array arranged parallel to the first linear array for detecting the first x-ray and the second x-ray which penetrate through a second plurality of parts of the object to acquire third values and fourth values for the second plurality of parts, wherein the object moves relative to the radiation source and first and second linear array along a straight line substantially perpendicular to a plane in which the x-rays are arranged, and the at least one of first plurality of parts is the same as at least one of the second plurality of parts;
a detector array comprising: a first linear array for detecting a first x-ray, a second x-ray and a third x-ray which penetrate through a first plurality of parts of an object under inspection to acquire first values, second values and third values for the first plurality of parts, wherein the first x-ray, the second x-ray and the third x-ray are alternately emitted from the radiation source; a second linear array arranged parallel to the first linear array for detecting the first x-ray, the second x-ray and the third x-ray which penetrate through the second plurality of parts of the object to acquire fourth values, fifth values and sixth values for the second plurality of parts, wherein at least one of the first plurality of parts is the same as at least one of the second plurality of pans; a third linear array arranged parallel to the first linear array and the second linear array for detecting the first x-ray, the second x-ray and the third x ray which penetrate through a third plurality of parts of the object to acquire seventh values, eighth values and ninth values for the third plurality of parts, wherein the object moves relative to the radiation source and first and second and third linear array along a straight line substantially perpendicular to a plane in which the x-rays are arranged, and at least one of the second plurality of parts is the same as at least one of the third plurality of parts; and
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Patent number: 7724869
Patent Publication Number: 20070286337
Inventors: Xuewu Wang (Beijing), Zhiqiang Chen (Beijing), Yuanjing Li (Beijing), Huaqiang Zhong (Beijing), Qingjun Zhang (Beijing), Shuqing Zhao (Beijing)
Application Number: 11/789,095
Current U.S. Class: Inspection Of Closed Container (378/57); Composition Analysis (378/53); With Solid-state Image Detector (378/98.8); With Plural X-ray Energies (378/98.9); With Image Subtraction (378/98.11)
International Classification: G01N 23/087 (20060101);