WO2019128697A1 - 辐射检查系统和辐射检查方法 - Google Patents

辐射检查系统和辐射检查方法 Download PDF

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Publication number
WO2019128697A1
WO2019128697A1 PCT/CN2018/120289 CN2018120289W WO2019128697A1 WO 2019128697 A1 WO2019128697 A1 WO 2019128697A1 CN 2018120289 W CN2018120289 W CN 2018120289W WO 2019128697 A1 WO2019128697 A1 WO 2019128697A1
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WO
WIPO (PCT)
Prior art keywords
collimating
inspection system
radiation inspection
radiation
neutron
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PCT/CN2018/120289
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English (en)
French (fr)
Inventor
杨祎罡
王东宇
于昊
宋全伟
李荐民
王伟珍
李玉兰
宗春光
张勤俭
曾鸣
陈志强
李元景
张丽
Original Assignee
清华大学
同方威视技术股份有限公司
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Application filed by 清华大学, 同方威视技术股份有限公司 filed Critical 清华大学
Publication of WO2019128697A1 publication Critical patent/WO2019128697A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • 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
    • G01V5/22—Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays
    • G01V5/222—Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays measuring scattered radiation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/005—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using neutrons
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/20—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • 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
    • G01V5/22—Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/02—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators
    • G21K1/04—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators using variable diaphragms, shutters, choppers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/10—Different kinds of radiation or particles
    • G01N2223/106—Different kinds of radiation or particles neutrons
    • G01N2223/1066—Different kinds of radiation or particles neutrons thermal
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/20—Sources of radiation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/30—Accessories, mechanical or electrical features
    • G01N2223/316—Accessories, mechanical or electrical features collimators
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/30—Accessories, mechanical or electrical features
    • G01N2223/32—Accessories, mechanical or electrical features adjustments of elements during operation

Definitions

  • the present disclosure relates to the field of radiation inspection technology, and in particular, to a radiation inspection system and a radiation inspection method.
  • strong penetration that is, the ability to penetrate the iron of the container and reach a certain depth of the detected object
  • characteristic information of the explosive for example, elemental composition
  • the principle of material identification based on X-ray source radiation inspection system is to identify different absorption curves of X-rays by using substances with different atomic coefficient elements, and it is necessary to simultaneously image X-rays using two or more energies.
  • This radiation inspection system distinguishes between substances with high atomic coefficients and low atomic coefficients, and thus distinguishes between organic and inorganic substances.
  • contraband can be checked by a neutron-based radiation inspection system.
  • the neutron has a strong penetrating ability.
  • the neutron-based radiation inspection system is capable of both large objects and elemental analysis. Therefore, the use of neutron inspection methods for the inspection of contraband such as explosives or drugs in large items has great advantages.
  • elemental analysis techniques are used to determine the elemental composition of organic matter. Using the interaction of neutrons and matter to identify the substance, based on the elemental content characteristics of the contraband and the reaction mechanism of the neutron and the nucleus, the H, C, N, and O in the substance are calculated by detecting the characteristic ⁇ energy spectrum of the detected object.
  • the elemental composition of the explosives is usually C, H, N, O, and has the characteristics of high content of N and O, and low content of H and C.
  • the detection and analysis of neutrons react with the detected object to release ⁇ .
  • the energy spectrum of the ray can detect the presence of explosives.
  • a first aspect of the present disclosure provides a radiation inspection system comprising a radiation source for emitting an initial beam and a beam modulation device for modulating the initial beam into a scanning beam, wherein the beam
  • the modulating device includes a first collimating structure disposed on a beam exit side of the radiation source and a second collimating structure disposed on a beam exit side of the first collimating structure, the first collimating structure including a first collimating opening, the second collimating structure includes a second collimating structure, and the second collimating structure is movably disposed opposite to the first collimating structure to change the first collimating port and a relative position of the second collimating port, wherein the beam modulating device switches between a first operating state and a second operating state, wherein in the first operating state, the beam modulating device
  • the initial beam modulation is a fan beam
  • the beam modulation device modulates the initial beam into a positionally variable pencil beam.
  • the second collimating structure and the first collimating structure are relatively translatable and/or rotatable relative to change the second collimating port and the The intersection of the first collimation opening perpendicular to the exit direction of the initial beam, thereby changing the position of the pencil beam.
  • the first collimating structure includes a first collimating plate; the second collimating structure includes a second collimating plate.
  • the first collimating plate is a first collimating plate
  • the second collimating plate is a second collimating plate; or the first collimating plate is a first collimating curved plate,
  • the second collimating plate is a second collimating curved panel.
  • the first collimating plate is parallel to the second collimating plate.
  • the first collimating opening is a first collimating slit; and the second collimating opening is a second collimating slit.
  • At least one of the first collimating slit and the second collimating slit is a linear collimating slit.
  • the second collimating slit is disposed obliquely or vertically with respect to the first collimating slit.
  • the first collimating structure is stationary, the second collimating structure is movably disposed; or the first collimating structure is movably disposed, and the second collimating structure is stationary; Alternatively, the first collimating structure and the second collimating structure are movably disposed.
  • the source of radiation comprises a source of neutrons.
  • the neutron source comprises a source of photoneutrons.
  • the radiation inspection system further includes a neutron modulation cover disposed at a periphery of the neutron source to modulate neutrons generated by the neutron source.
  • the neutron modulation mask includes a moderation layer disposed on a periphery of the neutron source to moderate neutrons generated by the neutron source.
  • the neutron modulation cover further includes a shielding layer disposed on an outer circumference of the moderation layer, including a shielding portion for shielding the moderated neutrons and being disposed at the beam exiting A neutron exit port for exiting the initial beam.
  • the shielding layer is also used to shield gamma rays.
  • the radiation inspection system further includes a detection device and a control device for receiving photons returned from the object to be inspected by the scanning beam, the control device and the detection device Coupling to receive a detection signal of the detection device and to form an inspection result based on the detection signal.
  • the detecting device includes a first detecting module and a second detecting module having an energy resolution higher than the first detecting module, wherein the first detecting module and the second detecting module are configured to receive a slave Detecting photons returned by the object to be inspected by the beam; the control device is coupled to the first detecting module to receive the first detecting signal of the first detecting module and form a first according to the first detecting signal Checking the result; the control device is further coupled to the second detection module to receive a second detection signal of the second detection module and to form a second inspection result according to the second detection signal.
  • the detecting means includes a first detecting module front collimating structure for controlling a beam shape of a photon entering the first detecting module; and/or the detecting means includes for controlling access a second detection module front collimation structure of a beam shape of the photons of the second detection module.
  • the second detection module in the second operational state, is fixed relative to the pencil beam during the detection process.
  • a second aspect of the present disclosure provides a radiation inspection method for inspecting an object to be inspected by using the radiation inspection system according to any one of the first aspects of the present disclosure, comprising: causing the beam modulation device to be in a first work a state in which the object to be inspected is scanned using the fan beam to determine a suspected area to be accurately inspected; the beam modulating device is placed in a second operational state, and the suspected area is accurately inspected using the pencil beam.
  • the radiation inspection system includes a first detection module and a second detection module having an energy resolution higher than the first detection module, the radiation inspection method including: in the first working state, The first detecting module is separately detected, or the first detecting module and the second detecting module simultaneously detect to determine the suspect area; in the second working state, the second detecting module separately detects, Or the first detecting module and the second detecting module simultaneously detect to accurately check the suspect area.
  • the beam modulating device can modulate the initial beam by changing the relative positions of the first collimating port of the first collimating structure and the second collimating port of the second collimating structure Switching between a first operational state of the fan beam and a second operational state of modulating the initial beam into a positionally variable pencil beam, thereby switching the radiation inspection system between the fan beam scanning inspection mode and the pencil beam scanning inspection mode .
  • a quick check is required, for example, when investigating a suspected area where a contraband may exist, it can work in the fan beam scan mode and can work when an accurate check is required, such as checking for suspect areas where a contraband may exist.
  • the inspection efficiency and inspection accuracy are balanced.
  • the radiation inspection method of the present disclosure has effects similar to those of the radiation inspection system of the present disclosure.
  • FIG. 1 is a schematic diagram of the principle of a radiation inspection system according to an embodiment of the present disclosure, wherein the beam modulation device is in a second operational state.
  • FIG. 2 is a schematic structural view of a radiation inspection system according to an embodiment of the present disclosure.
  • FIG. 3 is a schematic view showing the structure of a second collimating structure of the beam modulating device in the radiation inspection system shown in FIG. 2.
  • FIG. 4 is a schematic structural view of the radiation inspection system shown in FIG. 2, wherein the beam modulation device is in a first operational state.
  • FIG. 5 is a schematic structural view of the radiation inspection system shown in FIG. 2, wherein the beam modulation device is in a second operational state.
  • orientation words such as “front, back, up, down, left, right", “horizontal, vertical, vertical, horizontal” and “top, bottom”, etc. indicate the orientation.
  • positional relationship is generally based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of the description of the disclosure and the simplification of the description, which does not indicate or imply the indicated device or component. It must be constructed and operated in a specific orientation or in a specific orientation, and thus is not to be construed as limiting the scope of the disclosure; the orientations “inside and outside” refer to the inside and outside of the contour of the components themselves.
  • an embodiment of the present disclosure provides a radiation inspection system 100.
  • the radiation inspection system 100 includes a radiation source for emitting an initial beam, and a beam modulation device for modulating the initial beam into a scanning beam.
  • the radiation inspection system 100 further includes detection means for detecting photons R returned by the object to be scanned for scanning beam radiation, and control means coupled to the detection means for receiving the detection signals of the detection means and forming an inspection result based on the detection signals.
  • the beam modulating device includes a first collimating structure 114 disposed on a beam exit side of the radiation source and a second collimating structure 130 disposed on a beam exit side of the first collimating structure 114.
  • the first collimating structure 114 includes a first collimating opening 1141 and the second collimating structure 130 includes a second collimating opening 131.
  • the second collimating structure 130 is movably disposed opposite to the first collimating structure 114 to change the relative positions of the first collimating opening 1141 and the second collimating opening 131, so that the beam modulating device is in the first working state and the second Switch between working states.
  • the beam modulation device modulates the initial beam into a fan beam.
  • the beam modulation device modulates the initial beam into a positionally variable pencil beam.
  • the beam modulating device can be configured to modulate the initial beam into a first operational state of the fan beam by changing the relative positions of the first collimating port 1141 and the second collimating port 131.
  • the initial beam is modulated to switch between the second operational state of the positionally variable pencil beam, thereby causing the radiation inspection system 100 to switch between the fan beam scan inspection mode and the pencil beam scan inspection mode.
  • you need a quick check such as when you are looking into a suspected area where a contraband may exist
  • the inspection efficiency and inspection accuracy are balanced.
  • the radiation source is a neutron source 111.
  • the beam modulating means is for changing the shape and position of the initial beam N1 emitted by the neutron source 111.
  • the radiation inspection system 100 also includes a neutron modulation cover that is disposed on the outer periphery of the neutron source 111 to modulate the neutrons generated by the neutron source 111.
  • the neutron modulation cover includes a moderating layer 112 and a shielding layer 113.
  • the moderation layer 112 is disposed on the outer periphery of the neutron source 111 to moderate the neutrons generated by the neutron source 111.
  • the shielding layer 113 is disposed on the outer periphery of the moderating layer 112, and includes a shielding portion that shields the moderated neutrons and a neutron exit port that is disposed on the beam exiting side for emitting the initial beam N1.
  • Neutrons have the advantage of being highly penetrating and capable of elemental analysis. When neutrons react with different elements, they emit different characteristic energy photons. Based on the elemental content characteristics of the contraband and the reaction mechanism of the neutron and the nucleus, by detecting the characteristic ⁇ energy spectrum of the detected object, the elemental composition of the substance and the composition of each element can be determined, thereby distinguishing contraband from other substances. Therefore, it is essential to detect contraband items that are hidden in large objects to be inspected, such as containers and trucks. Prohibited items are, for example, drugs and explosives.
  • the neutron source 111 can take various forms of neutron source 111, such as a photoneutron source, a neutron generator, an isotope source, and the like.
  • the neutron source 111 is a light neutron source.
  • the photoneutron source may include an electron accelerating tube, an X-ray converting target, and a photoneutron target.
  • the X-ray conversion target can be made, for example, of gold and tungsten.
  • the photoneutrons are slowed down by the moderation layer 112 into thermal neutrons.
  • the light neutron source can meet the requirements for rapid inspection of large items. For the inspection of contraband, inspection efficiency is an important factor. For this reason, for neutron-based radiation inspection systems, it is necessary to ensure that the neutrons in the inspection channel have a higher fluence rate, so the neutron source used needs to have Higher neutron yield.
  • the yield of light neutrons is high, and the detection speed can be increased relative to the neutron generator and the isotopic neutron source.
  • the lifetime of the photoneutron source is long, while the commonly used isotopic neutron source such as 252Cf has a half-life of 2.65 years, and the average lifetime of an ordinary neutron generator is only a thousand hours.
  • the light neutron source is an electric ray source, which has good radiation safety and does not generate radiation during transportation, installation and commissioning.
  • the radiation inspection system 100 of the embodiment of the present disclosure uses a light neutron source as a radiation source, and can be applied in the field of safety inspection to identify contraband items such as drugs or explosives that may exist in large containers and large vehicles.
  • the photoneutron source generates photoneutrons by using X-rays generated by a pulsed electron linear accelerator and a photoneutron target.
  • the process of generating photoneutrons includes two processes of X-ray generation and photoneutron generation: accelerating electrons in an electron accelerating tube to form a high-energy electron beam, bombarding a high-Z material as an X-ray conversion target, and causing bremsstrahlung effect of electrons and high Z materials. , producing high energy X-rays. After the high-energy X-ray enters the photoneutron conversion target, it reacts with the nucleus to generate photoneutrons.
  • the neutron modulation mask is disposed outside the electron acceleration tube, the X-ray conversion target, and the photoneutron target.
  • the arrangement integrates the neutron modulation cover, the electron acceleration tube, the X-ray conversion target and the optical neutron target, and has convenient installation and debugging, low radiation and high safety.
  • the neutron source 111, the moderating layer 112, the shielding layer 113, and the first collimating structure 114 are integrated to form the radiation source device 110.
  • the X-ray conversion targets are all located within the photoneutron target. In other illustrated embodiments, the X-ray conversion target may be located partially within the photoneutron target or at a distance from the photoneutron target.
  • the photoneutron target may be a heavy water target or a helium target. Since the photon neutron reaction has an energy threshold, that is, only when the photon energy is greater than the neutron binding energy in the nucleus, the photoneutron reaction may occur. Therefore, an appropriate photoneutron conversion material must be selected to form the photoneutron target. Ensure that the reaction threshold is lower than the X-ray energy. The materials usually selected are lanthanum and cerium, and their photon reaction thresholds are 2.223 MeV and 1.67 MeV, respectively. In this embodiment, the photoneutron target is a heavy water target.
  • the heavy water target includes a sealed outer casing and heavy water enclosed in the sealed outer casing.
  • the top of the hermetic housing includes a recess in which the X-ray conversion target is located.
  • the hermetic housing can be, for example, an aluminum housing.
  • the X-ray conversion target protrudes into the heavy water target, and the X-ray is generated in the encirclement of heavy water during the electron shooting.
  • X-rays whose energy is higher than the threshold of photoneutron reaction can react with helium in heavy water to produce neutrons, and X-rays are fully utilized.
  • the heavy water target is a cylindrical target whose axis is disposed along the outgoing direction of the electron acceleration tube.
  • the electron accelerating tube, the X-ray conversion target and the optical neutron target are coaxially arranged.
  • the slowing layer 112 of the neutron modulation cover is disposed on the outer periphery of the neutron source 111 to slow down the light neutrons generated by the neutron source 111.
  • the moderating layer 112 is a graphite moderating layer.
  • the moderator layer 112 may also be constructed of other materials.
  • it may be a heavy water moderation layer or a combination of different slower material layers.
  • the heavy water moderated layer the heavy water is placed in a sealed enclosure.
  • the neutrons emitted by the photoneutron source are slowed down by the moderation layer 112 into thermal neutrons.
  • thermal neutrons have a larger cross section with the main elements in the contraband.
  • the shielding layer 113 is disposed on the outer periphery of the moderating layer 112, and includes a shielding portion that shields the moderated neutrons and a neutron exit port that transmits the neutrons disposed on the beam exiting side.
  • the electron beam current of the electron accelerating tube is axially beamed out, coaxial with the shielding layer 113, and the neutron exit port is disposed on the axial end surface of the shielding layer 113.
  • the electron accelerating tube can emit X-rays downward, while the neutron exit port is disposed at the side of the shielding layer.
  • This arrangement allows the light neutron source to be arranged such that the outgoing direction of the beam current is towards the ground, since the back side of the beam current is facing the sky, as long as the top does not require an operator, no special protection is required, and the beam direction is toward the ground, No special protection is required, so in this case the protection requirements for the top and bottom of the light neutron source can be reduced.
  • the beam modulating device includes a first collimating structure 114 disposed on a beam exit side of the radiation source and is disposed at the first collimation.
  • the second collimating structure 130 on the exit side of the beam of structure 114.
  • the first collimating structure 114 includes a first collimating opening 1141 and the second collimating structure 130 includes a second collimating opening 131.
  • the second collimating structure 130 is movably disposed relative to the first collimating structure 114 to change the relative positions of the first collimating opening 1141 and the second collimating opening 113, so that the beam modulating device is in the first working state and the second Switch between working states.
  • the beam modulating device can modulate the initial beam N1 into a fan beam N2, so that the radiation inspection system 100 can be operated in the fan beam scanning inspection mode to achieve rapid detection of the detected object.
  • the fan beam scanning mode is particularly suitable for locating suspect areas.
  • the beam modulating device can modulate the initial beam N1 into the pencil beam N3, so that the radiation inspection system 100 can be operated in the pencil beam scanning inspection mode to achieve accurate detection of the detected object, and is suitable for the suspect area. Perform accurate inspections.
  • the first collimating structure 114 includes a first collimating plate; and the second collimating structure 130 includes a second collimating plate. Wherein the first collimating plate is parallel to the second collimating plate.
  • the first collimating opening 1141 is a linear collimating slit; the second collimating opening 131 is a linear collimating slit.
  • the second collimating port 131 is disposed obliquely with respect to the first collimating port 1141.
  • the second collimating structure 130 In the first working state, the second collimating structure 130 is entirely located outside the fan beam N2 emerging from the first collimating port 1141.
  • the second collimating port 131 By translating the second collimating structure 130, the second collimating port 131 can be moved to the first The position where the collimation port 1141 intersects, thereby bringing the beam modulation device into the second operational state.
  • the translation of the second collimating structure 130 relative to the first collimating structure 114 may change the intersection position of the second collimating port 131 and the first collimating port 1141 perpendicular to the exit direction of the initial beam N1, Thereby, the outgoing position of the pencil beam N3 is changed.
  • the first collimating port 1141 of the first collimating structure 114 is vertically disposed.
  • the initial beam N1 emitted from the neutron source 111 passes through the first collimating port 1141 to form a fan beam N2.
  • the second collimating port 131 of the second collimating structure 130 is disposed obliquely with respect to a horizontal plane, and the first collimating port 1141 forms an acute angle with the second collimating port 131.
  • the second collimating structure 130 is parallel to the first collimating structure 114, and the second collimating structure 130 is horizontally displaceable in a direction parallel to the first collimating structure 114.
  • the beam modulating device may include a driving mechanism that is drivingly coupled to the second collimating structure 130 for achieving the required motion of the second collimating structure 130.
  • the drive mechanism can be coupled to the control device to act in accordance with a control command issued by the control device.
  • the first collimating structure 114 performs the initial beam N1.
  • the fan beam N2 is output, and the fan beam N2 scans the object to be detected and enters the object to be detected in the object to be detected.
  • a preliminary scan of the entire object to be inspected is completed by the relative positional movement of the radiation inspection system 100 and the object under inspection.
  • the fan beam N2 forms a pencil beam N3 under the modulation of the second collimating port 131, and the pen beam N3 is inspected.
  • the beam modulating device can be switched between the first operating state and the second operating state, and on the other hand, in the second operating state, the pencil beam N3 can be adjusted. position.
  • the vertical position can be changed in the case where the pencil beam N3 is unchanged in the horizontal position, thereby more accurately scanning the object to more accurately locate the position of the suspect and the composition of the suspect.
  • Both the first collimating structure 114 and the second collimating structure 130 may be in other forms.
  • the first collimating structure 114 and the second collimating structure 130 may each be a curved panel, and the curved panel is, for example, a curved panel.
  • the second collimating port 131 of the second collimating structure 130 can be perpendicular to the first collimating port 1141, and the collimating structure can be realized in the first working state and the second by shifting the second collimating structure 130 up and down. The switching between the two working states and the adjustment of the beaming position of the pencil beam in the second working state.
  • a third collimating port may be disposed on the second collimating structure 130.
  • the beam modulating device may also be disposed. In the first working state.
  • the first collimating structure is a first collimating flat plate provided with a linear collimating slit as a first collimating opening
  • the second collimating structure is provided with a linear collimating slit as a second collimating opening.
  • the switching between the first working state and the second working state and the second working can also be achieved by the relative rotation of the first collimating plate and the second collimating plate. The adjustment of the beam exit position of the pencil beam is achieved in the state.
  • the modulation function of the beam modulating device can also be implemented in steps, for example, the beam modulating device can be switched between the first working state and the second working state by relative rotation, and the pencil beam can be realized by the relative translation mode.
  • the adjustment of the beam exit position; or vice versa the beam modulation device is switched between the first working state and the second operating state by relative translation, and the adjustment of the beaming position of the pencil beam is achieved by the relative rotation mode.
  • the relative motion between the first collimating structure and the second collimating structure can also be achieved by a combined motion of translation and rotation to achieve a modulation function of the beam modulation device.
  • first collimating structure 114 is stationary, and the second collimating structure 130 is movably disposed.
  • first collimating structure may also be movably disposed, and the second collimating structure may be stationary.
  • the first collimating structure may be configured to include a first collimating slit that is inclined with respect to the water surface
  • the second collimating structure may be configured to include a vertical second collimating slit when the first collimating structure is from the initial beam current
  • the beam exiting side of the second collimated structure exits the fan beam
  • the beam modulation device is in the first working state
  • the first collimating structure moves to the first collimating slit and the second collimating slit
  • the beam exit side of the second collimating structure exits the pencil beam
  • the beam modulation device is in the second operational state.
  • the position change of the pencil beam can also be realized by moving the first collimating structure.
  • first collimating structure and the second collimating structure may be movably disposed to implement the beam modulating device between the first working state and the second working state. Switching, and changing the position of the pencil beam in the second working state.
  • the detecting means comprises a first detecting module 140 for receiving photons R returned from the object 210 to be inspected by the scanning beam, the control means being coupled to the first detecting module 140 for receiving the first detecting
  • the first detection signal of the module 140 forms a first inspection result according to the first detection signal.
  • the control device is not shown in FIGS. 1 to 5.
  • the first detecting module 140 includes a plurality of first detectors, and the plurality of first detectors are arranged on the side of the fan beam N2 to form a first detector array.
  • the plurality of first detectors are vertically arranged.
  • the first detector can for example be a NaI crystal detector.
  • the detection device also includes a first detection module front collimation structure 150 for controlling the beam shape of the photons R entering the first detection module 140.
  • the detecting device further comprises a second detecting module 160 for receiving the photons R returned from the inspected object 210 irradiated by the scanning beam, the control device being coupled with the second detecting module 160 to receive the second detecting module 160
  • the second detection signal forms a second inspection result according to the second detection signal, and the energy resolution of the second detection module 160 is better than the energy resolution of the first detection module 140.
  • the second detecting module 160 includes a second detector.
  • the array of second detection modules 160 may also include a plurality of second detectors arranged in a side of the fan beam N2 to form a second detector array.
  • the energy resolution of the second detecting module 160 in this embodiment is superior to that of the first detecting module 140.
  • the second detector can for example be a high purity helium detector. Setting the second detection module 160 facilitates a more accurate inspection.
  • the detection device may also include a second detection module front collimation structure for controlling the beam shape of the photons R entering the second detection module 160.
  • the radiation inspection system of the present disclosure may further include a housing 170 in which the radiation source and the beam modulation device are disposed.
  • the detecting module may be disposed in the housing 170 or may be disposed outside the housing 170, for example, may be disposed on the housing 170.
  • the inspection process of the radiation inspection system 100 will be described by taking the radiation inspection system 100 as an example of the inspection container 200 to be inspected.
  • the neutron source 111 produces photoneutrons, which are slowed down to become thermal neutrons.
  • the shield layer 113 shields neutrons other than the beam direction such that the radiation source device 110 emits only the initial beam N1 from the neutron exit port. If the neutron source 111 generates neutrons while also generating other rays, the shielding layer 113 can also function to shield other rays.
  • the beam modulating device is placed in the first operational state.
  • the first collimating structure 114 is modulated by the initial beam N1 to be emitted into the fan beam N2.
  • the fan beam N2 passes through the container wall of the inspection container 200 into the inside of the inspection container 200, and is irradiated onto the object to be inspected 210.
  • a photon R containing characteristic gamma rays is emitted.
  • the photon R is collimated by the first detection module front collimation structure 150 to form a photon beam current.
  • the photon beam stream enters the first detection module 140.
  • the first detecting module 140 detects the characteristic gamma rays in the photon R to form a first detecting signal.
  • the control device forms a first inspection result based on the first detection signal. According to the first inspection result, it can be determined whether or not there is a suspected area in the inspected container 200 where the contraband may be present.
  • the first detecting module 140 After being detected by the first detecting module 140, if it is found that there is a suspected area of the contraband according to the first inspection result, more accurate detection is performed on the suspect area. This embodiment assumes that the area where the object 210 to be inspected is a suspect area.
  • the beam modulating device is placed in the second operating state.
  • the first collimating structure 114 modulates the initial beam N1 to make it into a fan beam N2, and the second collimating structure 130 further expands the fan beam N2. After modulation, it becomes a variable-shaped pencil beam N3.
  • the second collimating port 131 of the second collimating structure 130 can pass the fan shape after passing through the first collimating port 1141 of the first collimating structure 114.
  • the beam N2 is further collimated into a pencil beam N3, and in the case where the horizontal position of the pencil beam N3 is constant, the vertical position of the pencil beam N3 is changed, and a more precise scanning is performed to more accurately locate the position of the suspect.
  • the pen beam N3 After the pen beam N3 enters the object to be inspected 210, it reacts with the object to be inspected 210 to emit characteristic gamma rays.
  • the second detecting module 160 having better energy resolution detects the characteristic gamma rays in the photons R returned from the object to be inspected 210 to form a second detecting signal.
  • the control device forms a second inspection result based on the second detection signal. According to the second inspection result, the position of the contraband that may exist may be more accurately positioned, and the elements of the contraband that may exist may be more accurately analyzed.
  • the second detecting module 160 When operating in the fan beam scanning inspection mode, the second detecting module 160 may be detected simultaneously with the first detecting module 140 or may be separately detected by the first detecting module 140. During the precise scanning, the second detecting module 160 may be detected simultaneously with the first detecting module 140, or may be separately detected by the second detecting module 160. In addition, if the accuracy of the detector is sufficient, only one set of detectors can be set.
  • the second detection module 160 in the second operational state of the beam modulation device, is fixed relative to the pencil beam N3 during the detection process, ie, the second detection module 160 moves synchronously with the pencil beam.
  • High energy resolution detectors are available at a higher price, which allows for precise scanning with as few second detectors as possible, reducing system cost.
  • the embodiment of the present disclosure also provides a radiation inspection method for inspecting an object to be inspected by the aforementioned radiation inspection system 100.
  • the radiation inspection method comprises: placing the beam modulating device in a first working state, scanning the object to be inspected using the fan beam N2, determining a suspect area to be accurately inspected; placing the beam modulating device in a second working state, using a pencil beam N3 pair The suspect area is subject to an accurate inspection.
  • the second detecting module 160 may be detected simultaneously with the first detecting module 140, or may be separately detected by the first detecting module 140. In the second working state, the second detecting module 160 may be detected simultaneously with the first detecting module 140, or may be separately detected by the second detecting module 160.
  • the first inspection result is obtained by performing fan beam scanning on the object to be inspected, and the suspect area is determined. If a suspect area is found, the suspect area is further scanned by a pencil beam scan to increase the accuracy of substance identification.
  • the embodiments of the present disclosure can identify substances in large containers and large vehicles, and identify contraband items such as drugs or explosives that may exist, which is of great significance for safety inspection.
  • contraband items such as drugs or explosives that may exist, which is of great significance for safety inspection.
  • the gamma ray generated by the neutron and the material reaction is used for material identification, and the elemental composition of the organic matter can be obtained to distinguish the drug, the explosive or the general organic matter with high accuracy.

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Abstract

一种辐射检查系统（100）和辐射检查方法。辐射检查系统（100）包括辐射源和射束调制装置，射束调制装置包括设置于辐射源的射束出射侧的第一准直结构（114）和设置于第一准直结构的射束出射侧的第二准直结构（130），第二准直结构（130）与第一准直结构（114）相对可动地设置以改变第一准直结构（114）的第一准直口和第二准直结构的第二准直口的相对位置，使射束调制装置在第一工作状态和第二工作状态之间切换，其中，在第一工作状态，射束调制装置将初始射束调制为扇形束，在第二工作状态，射束调制装置将初始射束调制为位置可变的笔形束。辐射检查系统和辐射检查方法兼顾检查效率和检查精度。

Description

辐射检查系统和辐射检查方法
相关申请
本申请是以申请号为201711429492.6，申请日为2017年12月26日，发明名称为“辐射检查系统和辐射检查方法”的中国专利申请为基础，并主张其优先权，该中国专利申请的公开内容在此作为整体引入本申请中。
技术领域
本公开涉及辐射检查技术领域，特别涉及一种辐射检查系统和辐射检查方法。
背景技术
在安全检查领域，物质识别，特别是对如毒品、爆炸物等违禁品的识别具有非常重要的意义。
对于藏匿在大型物品例如集装箱中的爆炸物品的检测，需要两个基本的条件：穿透能力强，即能够穿透集装箱的铁皮，并达到被检测物品的一定深度；能够获取爆炸物的特征信息，例如元素组成。
基于X射线源的辐射检查系统进行物质识别的原理是利用含不同原子系数元素的物质对X射线的不同吸收曲线来识别，需利用两种或以上能量的X射线同时成像。这种辐射检查系统可区分高原子系数和低原子系数的物质，进而区分有机物和无机物。
另外，可通过基于中子的辐射检查系统检查违禁品。中子的穿透能力较强，同时，通过探测与分析中子与被检查物体发生反应后放出γ射线的能谱，可以检测违禁品是否存在。基于中子的辐射检查系统既能够穿透大型物品又能进行元素分析。因此，利用中子检查方式进行大型物品中的爆炸物或毒品等违禁品检查具有很大的优势。
在利用中子检查方式探测违禁品的过程中，利用元素分析技术判断有机物的元素组成。利用中子与物质的相互作用进行物质识别，基于违禁品的元素含量特征和中子与原子核的反应机理，通过探测被检测物的特征γ能谱，计算出物质中H、C、N、O、Cl等有机物的元素的组成和比例关系，识别物质，达到违禁品检查的目的。
以检查爆炸物和毒品为例：
对于爆炸物的检查。爆炸物的元素组成通常为C、H、N、O，而且具有N和O的含量较高，H和C的含量很少的特点，通过探测与分析中子与被检测物体发生反应后放出γ射线的能谱，可以检测爆炸物是否存在。
对于毒品的检查。在许多毒品的制备过程中，需要含氯物质的参与，如盐酸、三 氯甲烷、二氯甲烷、二氯乙烷、二氯乙烯等，因此氯也会出现在很多制成的毒品中。通过分析H、N、Cl等元素的比例关系来对毒品/易制毒物质存在的可能性和种类进行判断。
在现有辐射检查系统中，有的通过扇形束对被检查对象进行检查，有的通过笔形束对被检查对象进行检查，二者均不能兼顾检查效率和检查精度。
发明内容
本公开的目的在于提供一种辐射检查系统和辐射检查方法，旨在兼顾检查效率和检查精度。
本公开第一方面提供一种辐射检查系统，包括用于发射初始射束的辐射源和用于将所述初始射束调制为扫描射束的射束调制装置，其特征在于，所述射束调制装置包括设置于所述辐射源的射束出射侧的第一准直结构和设置于所述第一准直结构的射束出射侧的第二准直结构，所述第一准直结构包括第一准直口，所述第二准直结构包括第二准直口，所述第二准直结构与所述第一准直结构相对可动地设置以改变所述第一准直口和所述第二准直口的相对位置，使所述射束调制装置在第一工作状态和第二工作状态之间切换，其中，在所述第一工作状态，所述射束调制装置将所述初始射束调制为扇形束，在所述第二工作状态，所述射束调制装置将所述初始射束调制为位置可变的笔形束。
在一些实施例中，在所述第二工作状态，所述第二准直结构与所述第一准直结构可相对平移和/或可相对转动以改变所述第二准直口与所述第一准直口的垂直于所述初始射束的出射方向的交叉位置，从而改变所述笔形束的位置。
在一些实施例中，所述第一准直结构包括第一准直板；所述第二准直结构包括第二准直板。
在一些实施例中，所述第一准直板为第一准直平板，所述第二准直板为第二准直平板；或者，所述第一准直板为第一准直曲面板，所述第二准直板为第二准直曲面板。
在一些实施例中，所述第一准直板平行于所述第二准直板。
在一些实施例中，所述第一准直口为第一准直缝；所述第二准直口为第二准直缝。
在一些实施例中，所述第一准直缝和所述第二准直缝中至少一个为直线型准直缝。
在一些实施例中，所述第二准直缝相对于所述第一准直缝倾斜设置或垂直设置。
在一些实施例中，所述第一准直结构静止，所述第二准直结构可动地设置；或者，所述第一准直结构可动地设置，所述第二准直结构静止；或者，所述第一准直结构和所述第二准直结构均可动地设置。
在一些实施例中，所述辐射源包括中子源。
在一些实施例中，所述中子源包括光中子源。
在一些实施例中，所述辐射检查系统还包括中子调制罩，所述中子调制罩设置于所述中子源外周，以对所述中子源产生的中子进行调制。
在一些实施例中，所述中子调制罩包括慢化层，所述慢化层设置于所述中子源外周以慢化所述中子源产生的中子。
在一些实施例中，所述中子调制罩还包括屏蔽层，所述屏蔽层设置于所述慢化层的外周，包括屏蔽慢化后的中子的屏蔽部和设置于所述射束出射侧的用于出射所述初始射束的中子出射口。
在一些实施例中，所述屏蔽层还用于屏蔽γ射线。
在一些实施例中，所述辐射检查系统还包括探测装置和控制装置，所述探测装置用于接收从所述扫描射束辐射的被检查物体返回的光子，所述控制装置与所述探测装置耦合以接收所述探测装置的探测信号并根据所述探测信号形成检查结果。
在一些实施例中，所述探测装置包括第一探测模块和能量分辨率高于所述第一探测模块的第二探测模块，所述第一探测模块和所述第二探测模块用于接收从所述扫描射束辐射的被检查物体返回的光子；所述控制装置与所述第一探测模块耦合以接收所述第一探测模块的第一探测信号并根据所述第一探测信号形成第一检查结果；所述控制装置还与所述第二探测模块耦合以接收所述第二探测模块的第二探测信号并根据所述第二探测信号形成第二检查结果。
在一些实施例中，所述探测装置包括用于控制进入所述第一探测模块的光子的束流形状的第一探测模块前准直结构；和/或，所述探测装置包括用于控制进入所述第二探测模块的光子的束流形状的第二探测模块前准直结构。
在一些实施例中，在所述第二工作状态，所述第二探测模块在探测过程中与所述笔形束相对位置固定。
本公开第二方面提供一种利用本公开第一方面中任一项所述的辐射检查系统检查被检查对象的辐射检查方法，其特征在于，包括：使所述射束调制装置处于第一工作状态，使用所述扇形束扫描所述被检查对象，确定需精确检查的嫌疑区域；使所述 射束调制装置处于第二工作状态，使用所述笔形束对所述嫌疑区域进行精确检查。
在一些实施例中，所述辐射检查系统包括第一探测模块和能量分辨率高于所述第一探测模块的第二探测模块，所述辐射检查方法包括：在所述第一工作状态，所述第一探测模块单独探测，或者，所述第一探测模块与所述第二探测模块同时探测，以确定所述嫌疑区域；在所述第二工作状态，所述第二探测模块单独探测，或者所述第一探测模块与所述第二探测模块同时探测，以对所述嫌疑区域进行精确检查。
基于本公开提供的辐射检查系统，可以通过改变第一准直结构的第一准直口和第二准直结构的第二准直口的相对位置，使射束调制装置在将初始射束调制为扇形束的第一工作状态和将初始射束调制为位置可变的笔形束的第二工作状态之间切换，从而使辐射检查系统在扇形束扫描检查模式和笔形束扫描检查模式之间切换。在需要快速检查时，例如在查探可能存在违禁品的嫌疑区域时，可以工作在扇形束扫描检查模式下，在需要精确检查时，例如对可能存在违禁器的嫌疑区域进行检查时，可以工作在笔形束扫描检查模式下，从而兼顾检查效率和检查精度。
本公开的辐射检查方法具有与本公开的辐射检查系统类似的效果。
通过以下参照附图对本公开的示例性实施例的详细描述，本公开的其它特征及其优点将会变得清楚。
附图说明
此处所说明的附图用来提供对本公开的进一步理解，构成本申请的一部分，本公开的示意性实施例及其说明用于解释本公开，并不构成对本公开的不当限定。在附图中：
图1为本公开实施例的辐射检查系统的原理示意图，其中射束调制装置处于第二工作状态。
图2为本公开实施例的辐射检查系统的结构示意图。
图3为图2所示的辐射检查系统中射束调制装置的第二准直结构的结构示意图。
图4为图2所示的辐射检查系统的结构示意图，其中射束调制装置处于第一工作状态。
图5为图2所示的辐射检查系统的结构示意图，其中射束调制装置处于第二工作状态。
图1至图5中，各附图标记分别代表：
100、辐射检查系统；
110、辐射源装置；
111、中子源；
112、慢化层；
113、屏蔽层；
114、第一准直结构；
1141、第一准直口；
130、第二准直结构；
131、第二准直口；
140、第一探测模块；
150、探测器前准直结构；
160、第二探测模块；
170、系统箱体；
200、被检查容器；
210、被检查物体；
N1、初始射束；
N2、扇形束；
N3、笔形束；
R、光子。
具体实施方式
下面将结合本公开实施例中的附图，对本公开实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本公开一部分实施例，而不是全部的实施例。以下对至少一个示例性实施例的描述实际上仅仅是说明性的，决不作为对本公开及其应用或使用的任何限制。基于本公开中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本公开保护的范围。
除非另外具体说明，否则在这些实施例中阐述的部件和步骤的相对布置、数字表达式和数值不限制本公开的范围。同时，应当明白，为了便于描述，附图中所示出的各个部分的尺寸并不是按照实际的比例关系绘制的。对于相关领域普通技术人员已知的技术、方法和设备可能不作详细讨论，但在适当情况下，所述技术、方法和设备应 当被视为授权说明书的一部分。在这里示出和讨论的所有示例中，任何具体值应被解释为仅仅是示例性的，而不是作为限制。因此，示例性实施例的其它示例可以具有不同的值。应注意到：相似的标号和字母在下面的附图中表示类似项，因此，一旦某一项在一个附图中被定义，则在随后的附图中不需要对其进行进一步讨论。
在本公开的描述中，需要理解的是，使用“第一”、“第二”等词语来限定零部件，仅仅是为了便于对相应零部件进行区别，如没有另行声明，上述词语并没有特殊含义，因此不能理解为对本公开保护范围的限制。
在本公开的描述中，需要理解的是，方位词如“前、后、上、下、左、右”、“横向、竖向、垂直、水平”和“顶、底”等所指示的方位或位置关系通常是基于附图所示的方位或位置关系，仅是为了便于描述本公开和简化描述，在未作相反说明的情况下，这些方位词并不指示和暗示所指的装置或元件必须具有特定的方位或者以特定的方位构造和操作，因此不能理解为对本公开保护范围的限制；方位词“内、外”是指相对于各部件本身的轮廓的内外。
如图1至图5所示，本公开实施例提供一种辐射检查系统100。该辐射检查系统100包括用于发射初始射束的辐射源、用于将初始射束调制为扫描射束的射束调制装置。辐射检查系统100还包括用于探测扫描射束辐射的被检查物体返回的光子R的探测装置和与探测装置耦合以接收探装置的探测信号并根据探测信号形成检查结果的控制装置。
射束调制装置包括设置于辐射源的射束出射侧的第一准直结构114和设置在第一准直结构114的射束出射侧的第二准直结构130。第一准直结构114包括第一准直口1141，第二准直结构130包括第二准直口131。第二准直结构130与第一准直结构114相对可动地设置以改变第一准直口1141和第二准直口131的相对位置，使射束调制装置在第一工作状态和第二工作状态之间切换。在第一工作状态，射束调制装置将初始射束调制为扇形束。在第二工作状态，射束调制装置将初始射束调制为位置可变的笔形束。
基于本公开提供的辐射检查系统100，可以通过改变第一准直口1141和第二准直口131的相对位置，使射束调制装置在将初始射束调制为扇形束的第一工作状态和将初始射束调制为位置可变的笔形束的第二工作状态之间切换，从而使辐射检查系统100在扇形束扫描检查模式和笔形束扫描检查模式之间切换。在需要快速检查时，例如在查探可能存在违禁品的嫌疑区域时，可以工作在扇形束扫描检查模式下，在需要 精确检查时，例如对可能存在违禁品的嫌疑区域进行检查时，可以工作在笔形束扫描检查模式下，从而兼顾检查效率和检查精度。
如图1至图5所示，本公开实施例中，辐射源为中子源111。射束调制装置用于改变中子源111发出的初始射束N1的形状和位置。
辐射检查系统100还包括中子调制罩，中子调制罩设置于中子源111外周，以对中子源111产生的中子进行调制。
中子调制罩包括慢化层112和屏蔽层113。慢化层112设置于中子源111外周以慢化中子源111产生的中子。屏蔽层113设置于慢化层112的外周，包括屏蔽慢化后的中子的屏蔽部和设置于射束出射侧的用于出射初始射束N1的中子出射口。
中子具有穿透力强、能够进行元素分析的优点。中子在与不同的元素发生反应时，发射出不同的特征能量光子。基于违禁品的元素含量特征和中子与原子核的反应机理，通过探测被检测物的特征γ能谱，可以确定物质的元素组成以及各元素的成分，从而区分违禁品与其他物质。因此具备检测藏匿在大型被检查对象例如集装箱、货车车厢中的违禁品的基本条件。违禁品例如为毒品和爆炸物。
中子源111可以采用各种形式的中子源111，例如光中子源、中子发生器、同位素源等。本实施例中，中子源111为光中子源。光中子源可以包括电子加速管、X射线转化靶和光中子靶。X射线转化靶例如可以由金和钨制成。光中子经过慢化层112慢化成为热中子。
光中子源可满足对大体积物品进行快速检查的要求。对于违禁品检查领域，检查效率是一个重要的因素，为此，对于基于中子的辐射检查系统，需保证检查通道内的中子具有较高的注量率，因此采用的中子源需要有较高的中子产额。光中子的产额高，相对于中子发生器和同位素中子源，可以提高检测速度。光中子源的寿命长，而常用的同位素中子源例如252Cf，半衰期为2.65年，普通中子发生器的寿命最高也仅为上千小时。光中子源为电射线源，辐射安全性好，在运输、安装和调试过程不产生辐射。
本公开实施例的辐射检查系统100采用光中子源作为辐射源，可应用在安全检查领域，对大型集装箱、大型车辆内可能存在的毒品或爆炸物等违禁品进行识别。
本公开中，光中子源利用脉冲电子直线加速器产生的X射线与光中子靶作用产生光中子。产生光中子的过程包括X射线生成和光中子产生两个过程：在电子加速管内加速电子形成高能电子束后轰击作为X射线转化靶的高Z材料，电子与高Z材料发生轫致辐射作用，产生高能X射线。高能X射线进入光中子转换靶之后与原子核发生 光中子反应，产生光中子。
本实例中，中子调制罩罩设于电子加速管、X射线转化靶和光中子靶外部。该设置使中子调制罩、电子加速管、X射线转化靶和光中子靶整合为一体，安装调试方便，辐射低、安全性高。本实施例中，中子源111、慢化层112、屏蔽层113和第一准直结构114集成在一起，形成辐射源装置110。
本实施例，X射线转化靶全部位于光中子靶内。在其它示图示的实施例中，X射线转化靶可以部分位于光中子靶内，也可以与光中子靶有一定的距离。
其中，光中子靶可以为重水靶，也可以为铍靶。由于光中子反应存在能量阈值，即只有光子的能量大于中子在原子核中的结合能时，光中子反应才有可能发生，因此须选择适当的光中子转换材料形成光中子靶，保证其反应阈值低于X射线能量。通常选取的材料是氘和铍，其光子反应阈值分别为2.223MeV和1.67MeV。本实施例中，光中子靶为重水靶。
重水靶包括密闭外壳和封闭设置于密闭外壳内的重水。密闭外壳的顶部包括凹入部，X射线转化靶位于凹入部内。密闭外壳例如可以为铝外壳。本实施例中，X射线转换靶伸入重水靶中，电子打靶的过程中X射线产生于重水的包围中。X射线产生的同时，能量高于光中子反应阈值的X射线可与重水中的氘反应产生中子，X射线被充分利用。
本实施例中，重水靶为轴线沿电子加速管的出束方向设置的圆柱靶。电子加速管、X射线转化靶和光中子靶同轴设置。
本实施例中，中子调制罩的慢化层112设置于中子源111外周以慢化中子源111产生的光中子。本实施例中慢化层112为石墨慢化层。
其它未图示的实施例中，慢化层112也可以由其它材料构成。例如也可以为重水慢化层，或者可以是不同慢化材料层的组合。重水慢化层中，重水容置于密闭外壳内。
光中子源发射出的中子被慢化层112慢化为热中子。相比于快中子，热中子与违禁品中的主要元素的反应截面更大。
屏蔽层113设置于慢化层112的外周，包括屏蔽慢化后的中子的屏蔽部和设置于射束出射侧的透射中子的中子出射口。
本实施例中，电子加速管的电子束流轴向出束，与屏蔽层113同轴，而中子出射口设置于屏蔽层113的轴向端面上。
在一些未示出的实施例中，电子加速管可以向下发射X射线，而中子出射口设置 于屏蔽层的侧部。该设置使得光中子源可以布置为电子束流的出束方向朝向地面，由于电子束流的背侧朝向天空，只要顶部不需操作人员，则无需特殊防护，而出束方向朝向地面，也无需特殊防护，因此在这种情况下可以降低对光中子源顶部和底部的防护需求。
如图1、图2和图5所示，本实施例的辐射检查系统100中，射束调制装置包括设置于辐射源的射束出射侧的第一准直结构114和设置在第一准直结构114的射束出射侧的第二准直结构130。第一准直结构114包括第一准直口1141，第二准直结构130包括第二准直口131。第二准直结构130相对于第一准直结构114可动地设置以改变第一准直口1141和第二准直口113的相对位置，使射束调制装置在第一工作状态和第二工作状态之间切换。
在第一工作状态，射束调制装置可以将初始射束N1调制为扇形束N2，从而可以使辐射检查系统100工作于扇形束扫描检查模式，实现被检测物体的快速检测。扇形束扫描模式尤其适于定位嫌疑区域。在第二工作状态，射束调制装置可以将初始射束N1调制为笔形束N3，从而可以使辐射检查系统100工作于笔形束扫描检查模式，实现被检测物体的精确检测，适于对嫌疑区域进行精确检测。
如图1至图5所示，本实施例中，第一准直结构114包括第一准直平板；第二准直结构130包括第二准直平板。其中，第一准直平板平行于第二准直平板。
本实施例中，第一准直口1141为直线型准直缝；第二准直口131为直线型准直缝。
本实施例中，第二准直口131相对于第一准直口1141倾斜设置。在第一工作状态，第二准直结构130整体位于从第一准直口1141出射的扇形束N2外侧，通过平移第二准直结构130，可以使第二准直口131移动至与第一准直口1141交叉的位置，从而使射束调制装置进入第二工作状态。在第二工作状态，第二准直结构130相对于第一准直结构114平移可以改变第二准直口131与第一准直口1141的垂直于初始射束N1的出射方向的交叉位置，从而改变笔形束N3的出束位置。
如图2所示，本实施例中，第一准直结构114的第一准直口1141竖直设置。从中子源111发出的初始束流N1经过第一准直口1141后形成扇形束N2。如图3所示，第二准直结构130的第二准直口131相对于水平面倾斜设置，第一准直口1141与第二准直口131形成锐角夹角。本实施例中，第二准直结构130与第一准直结构114平行，且第二准直结构130沿平行于第一准直结构114的方向可水平移动地设置。
其中，射束调制装置可以包括驱动机构，驱动机构与第二准直结构130驱动连接用于实现第二准直结构130所需的运动。驱动机构可以与控制装置耦合，以根据控制装置发出的控制指令动作。
如前所述，当第二准直结构130位于第一准直口1141出射的扇形束N2的外侧时，准直结构处于第一工作状态。如图4所示(因第二准直结构130在此时未起到准直作用，图4中未示出第二准直结构130)，第一准直结构114在对初始射束N1进行调制后输出扇形束N2，扇形束N2对被检测对象进行扫描，射入被检测对象内的被检测物体。通过辐射检查系统100和被检查对象的相对位置移动，完成对整个被检查对象的初步扫描。
当第二准直结构130移动至第第一准直口1141和第二准直口131交叉，扇形束N2在第二准直口131的调制下形成笔形束N3，笔形束N3射向被检查对象。通过调整第二准直结构130的水平位置一方面可以使射束调制装置在第一工作状态和第二工作状态之间切换，另一方面，在第二工作状态时，可以调节笔形束N3的位置。本实施例中，可以使得笔形束N3在水平位置不变的情况下，垂直位置发生改变，从而对被检物进行更精确的扫描，以更加精确地定位嫌疑物的位置和嫌疑物的成分。
第一准直结构114和第二准直结构130均可以为其他形式。例如，第一准直结构114和第二准直结构130均可以为曲面板，曲面板例如为弧形板。再例如，可以使第二准直结构130的第二准直口131垂直于第一准直口1141，通过使第二准直结构130上下平移的方式实现准直结构在第一工作状态和第二工作状态之间的切换以及在第二工作状态下实现笔形束的出束位置的调节。
又例如，第二准直结构130上也可以设置第三准直口，当第二准直结构130移动至第三准直口与第一准直口1141平行时，也可以使射束调制装置处于第一工作状态。
又例如，对于第一准直结构为设置有直线型准直缝作为第一准直口的第一准直平板，第二准直结构为设置有直线型准直缝作为第二准直口的第二准直平板的情况下，还可以通过第一准直平板和第二准直平板相对转动的方式实现准直结构在第一工作状态和第二工作状态之间的切换以及在第二工作状态下实现笔形束的出束位置的调节。
当然，还可以分步骤实现射束调制装置的调制功能，例如，可以通过相对转动方式实现射束调制装置在第一工作状态和第二工作状态之间的切换而通过相对平动方式实现笔形束的出束位置的调节；或者反之，通过相对平动方式实现射束调制装置在 第一工作状态和第二工作状态之间的切换而通过相对转动方式实现笔形束的出束位置的调节。另外，也可以通过平移和转动的复合运动实现第一准直结构和第二准直结构之间的相对运动以实现射束调制装置的调制功能。
另外，以上实施例中，第一准直结构114静止，第二准直结构130可动地设置。在一些未图示的实施例中，也可以是第一准直结构可动地设置，第二准直结构静止。例如，第一准直结构可以设置为包括相对于水面倾斜的第一准直缝，而第二准直结构可以设置为包括垂直的第二准直缝，当第一准直结构从初始束流的辐射路径中抽离时，第二准直结构的射束出射侧出射扇形束，射束调制装置处于第一工作状态，第一准直结构移动至第一准直缝与第二准直缝交叉的位置，则第二准直结构的射束出射侧出射笔形束，射束调制装置处于第二工作状态。第二工作状态下，亦可通过移动第一准直结构实现笔形束的位置变化。
当然，在一些未图示的实施例中，也可以是第一准直结构和第二准直结构均可动地设置，以实现射束调制装置在第一工作状态和第二工作状态之间的切换，以及实现在第二工作状态时笔形束位置的改变。
如图1至图5所示，探测装置包括用于接收从扫描射束辐射的被检查物体210返回的光子R的第一探测模块140，控制装置与第一探测模块140耦合以接收第一探测模块140的第一探测信号并根据第一探测信号形成第一检查结果。其中，图1至图5中未示出控制装置。
本实施例中，第一探测模块140包括多个第一探测器，多个第一探测器排列于扇形束N2的侧方，形成第一探测器阵列。本实施例中与扇形束N2上下出束相应地，多个第一探测器竖直排列。第一探测器例如可以为NaI晶体探测器。
探测装置还包括第一探测模块前准直结构150，用于控制进入第一探测模块140的光子R的束流形状。
本实施例中，探测装置还包括用于接收从扫描射束辐射的被检查物体210返回的光子R的第二探测模块160，控制装置与第二探测模块160耦合以接收第二探测模块160的第二探测信号并根据第二探测信号形成第二检查结果，第二探测模块160的能量分辨率优于第一探测模块140的能量分辨率。
本实施例中，第二探测模块160包括一个第二探测器。在未图示的实施例中，第二探测模块160阵列也可以包括多个第二探测器，第二探测器排列于扇形束N2的侧方，排布形成第二探测器阵列。本实施例中第二探测模块160的能量分辨率优于第一 探测模块140。第二探测器例如可以为高纯锗探测器。设置第二探测模块160有利于进行更精确的检查。
在未图示的实施例中，探测装置也可以包括用于控制进入第二探测模块160的光子R的束流形状的第二探测模块前准直结构。
另外，如图2、图4和图5所示，本公开的辐射检查系统还可以包括壳体170，辐射检查系统100的辐射源和射束调制装置设置于壳体170内。探测模块可以设置于壳体170内，也可以设置于壳体170外，例如可以设置于壳体170上。
如图1至图5所示，本实施例中以辐射检查系统100检查作为被检查对象的被检查容器200为例对辐射检查系统100的检查过程进行说明。
中子源111产生光中子，光中子经过慢化成为热中子。屏蔽层113将除出束方向以外的中子屏蔽，使得辐射源装置110只从中子出射口发出初始射束N1。若中子源111产生中子的同时也产生其它射线，屏蔽层113还可起到屏蔽其它射线的作用。
使射束调制装置处于第一工作状态，此时，第一准直结构114在对初始射束N1调制后使之成为扇形束N2射出。扇形束N2穿过被检查容器200的容器壁进入被检查容器200内部，照射于被检查物体210。与被检查物体210反应后放出包含特征γ射线的光子R。光子R经第一探测模块前准直结构150准直后形成光子束流。光子束流进入第一探测模块140。第一探测模块140探测光子R中的特征γ射线，形成第一探测信号。控制装置根据第一探测信号形成第一检查结果。根据第一检查结果可以判断被检查容器200内是否具有可能存在违禁品的嫌疑区域。
经过第一探测模块140探测后，若根据第一检查结果发现可能存在违禁品的嫌疑区域，则针对该嫌疑区域进行更加精确的探测。本实施例假设被检查物体210所在区域为嫌疑区域。
使射束调制装置处于第二工作状态，此时，第一准直结构114在对初始射束N1进行调制后使之成为扇形束N2射出，再由第二准直结构130对扇形束N2进一步调制后使之成为位置可变的笔形束N3。本实施例中，通过水平移动第二准直结构130的位置，利用第二准直结构130的第二准直口131可将经过第一准直结构114的第一准直口1141后的扇形束N2进一步准直为笔形束N3，在笔形束N3水平位置不变的情况下，改变笔形束N3的垂直位置，进行更精确的扫描，更加精确地定位嫌疑物的位置。笔形束N3进入被检查物体210后，与被检查物体210反应放出特征γ射线。采用能量分辨率更优的第二探测模块160探测从被检查物体210返回的光子R中的特征γ射线， 形成第二探测信号。控制装置根据第二探测信号形成第二检查结果。根据第二检查结果对可能存在的违禁品藏匿的位置进行更精准的定位，以及对可能存在的违禁品的元素进行更精确的分析。
在扇形束扫描检查模式下工作时，第二探测模块160可以与第一探测模块140同时探测，也可由第一探测模块140单独探测。在精确扫描时，第二探测模块160可以与第一探测模块140同时探测，也可由第二探测模块160单独探测。另外，如果探测器的精度足够，也可以仅设置一组探测器。
在一些实施例中，在射束调制装置的第二工作状态，第二探测模块160在探测过程中与笔形束N3相对位置固定，即第二探测模块160与笔形束同步移动。高能量分辨率的探测器具有更高的价格，该设置可以采用尽量少的第二探测器实现精确扫描，从而可以减少系统成本。
本公开实施例还提供一种利用前述的辐射检查系统100检查被检查对象的辐射检查方法。该辐射检查方法包括：使射束调制装置处于第一工作状态，使用扇形束N2扫描被检查对象，确定需精确检查的嫌疑区域；使射束调制装置处于第二工作状态，使用笔形束N3对嫌疑区域进行精确检查。
其中，在第一工作状态，第二探测模块160可以与第一探测模块140同时探测，也可由第一探测模块140单独探测。在第二工作状态，第二探测模块160可以与第一探测模块140同时探测，也可由第二探测模块160单独探测。
本公开以上实施例的辐射检查系统100及辐射检查方法，通过对被检查对象进行扇形束扫描，得到第一检查结果，确定嫌疑区域。若发现嫌疑区域，通过笔形束扫描进一步对嫌疑区域进行精确扫描，以增加物质识别的准确性。
本公开实施例可对大型集装箱、大型车辆内的有机物进行物质识别，对可能存在的毒品或爆炸物等违禁品进行鉴别，对于安全检查具有重要的意义。在一些实施例中，利用中子和物质反应产生的特征γ射线进行物质识别，可以得到有机物的元素组成，以此区分是毒品、爆炸物或者是一般有机物，准确性较高。
最后应当说明的是：以上实施例仅用以说明本公开的技术方案而非对其限制；尽管参照较佳实施例对本公开进行了详细的说明，所属领域的普通技术人员应当理解：依然可以对本公开的具体实施方式进行修改或者对部分技术特征进行等同替换，其均应涵盖在本公开请求保护的技术方案范围当中。

Claims (21)

  1. 一种辐射检查系统(100)，包括用于发射初始射束(N1)的辐射源和用于将所述初始射束(N1)调制为扫描射束的射束调制装置，其特征在于，所述射束调制装置包括设置于所述辐射源的射束出射侧的第一准直结构(114)和设置于所述第一准直结构(114)的射束出射侧的第二准直结构(130)，所述第一准直结构(114)包括第一准直口(1141)，所述第二准直结构(130)包括第二准直口(131)，所述第二准直结构(130)与所述第一准直结构(114)相对可动地设置以改变所述第一准直口(1141)和所述第二准直口(131)的相对位置，使所述射束调制装置在第一工作状态和第二工作状态之间切换，其中，在所述第一工作状态，所述射束调制装置将所述初始射束(N1)调制为扇形束(N2)，在所述第二工作状态，所述射束调制装置将所述初始射束(N1)调制为位置可变的笔形束(N3)。
  2. 根据权利要求1所述的辐射检查系统(100)，其特征在于，在所述第二工作状态，所述第二准直结构(130)与所述第一准直结构(114)可相对平移和/或可相对转动以改变所述第二准直口(131)与所述第一准直口(1141)的垂直于所述初始射束(N1)的出射方向的交叉位置，从而改变所述笔形束(N3)的位置。
  3. 根据权利要求1所述的射束调制装置(100)，其特征在于，所述第一准直结构(114)包括第一准直板；所述第二准直结构(130)包括第二准直板。
  4. 根据权利要求3所述的辐射检查系统(100)，其特征在于，所述第一准直板为第一准直平板，所述第二准直板为第二准直平板；或者，所述第一准直板为第一准直曲面板，所述第二准直板为第二准直曲面板。
  5. 根据权利要求3所述的辐射检查系统(100)，其特征在于，所述第一准直板平行于所述第二准直板。
  6. 根据权利要求1所述的辐射检查系统(100)，其特征在于，所述第一准直口(1141)为第一准直缝；所述第二准直口(131)为第二准直缝。
  7. 根据权利要求1所述的辐射检查系统(100)，其特征在于，所述第一准直缝和所述第二准直缝中至少一个为直线型准直缝。
  8. 根据权利要求7所述的辐射检查系统(100)，其特征在于，所述第二准直缝相对于所述第一准直缝倾斜设置或垂直设置。
  9. 根据权利要求1所述的辐射检查系统(100)，其特征在于，所述第一准直结构(114)静止，所述第二准直结构(130)可动地设置；或者，所述第一准直结构可动地设置，所述第二准直结构静止；或者，所述第一准直结构和所述第二准直结构均可动地设置。
  10. 根据权利要求1至9中任一项所述的辐射检查系统(100)，其特征在于，所述辐射源包括中子源(111)。
  11. 根据权利要求10所述的辐射检查系统(100)，其特征在于，所述中子源(111)包括光中子源。
  12. 根据权利要求10所述的辐射检查系统(100)，其特征在于，所述辐射检查系统(100)还包括中子调制罩，所述中子调制罩设置于所述中子源(111)外周，以对所述中子源(111)产生的中子进行调制。
  13. 根据权利要求12所述的辐射检查系统(100)，其特征在于，所述中子调制罩包括慢化层(112)，所述慢化层(112)设置于所述中子源(111)外周以慢化所述中子源(111)产生的中子。
  14. 根据权利要求13所述的辐射检查系统(100)，其特征在于，所述中子调制罩还包括屏蔽层(113)，所述屏蔽层(113)设置于所述慢化层(112)的外周，包括屏蔽慢化后的中子的屏蔽部和设置于所述射束出射侧的用于出射所述初始射束(N1)的中子出射口。
  15. 根据权利要求14所述的辐射检查系统(100)，其特征在于，所述屏蔽层(113)还用于屏蔽γ射线。
  16. 根据权利要求1至9中任一项所述的辐射检查系统(100)，其特征在于，所述辐射检查系统(100)还包括探测装置和控制装置，所述探测装置用于接收从所述扫描射束辐射的被检查物体(210)返回的光子(R)，所述控制装置与所述探测装置耦合以接收所述探测装置的探测信号并根据所述探测信号形成检查结果。
  17. 根据权利要求16所述的辐射检查系统(100)，其特征在于，所述探测装置包括第一探测模块(140)和能量分辨率高于所述第一探测模块的第二探测模块(160)，所述第一探测模块(140)和所述第二探测模块(160)用于接收从所述扫描射束辐射的被检查物体(210)返回的光子(R)；所述控制装置与所述第一探测模块(140)耦合以接收所述第一探测模块(140)的第一探测信号并根据所述第一探测信号形成第一检查结果；所述控制装置还与所述第二探测模块(160)耦合以接收所述第二探测模块(160)的第二探测信号并根据所述第二探测信号形成第二检查结果。
  18. 根据权利要求17所述的辐射检查系统(100)，其特征在于，所述探测装置包括用于控制进入所述第一探测模块(140)的光子(R)的束流形状的第一探测模块前准直结构(150)；和/或，所述探测装置包括用于控制进入所述第二探测模块(160)的光子(R)的束流形状的第二探测模块前准直结构。
  19. 根据权利要求17所述的辐射检查系统(100)，其特征在于，在所述第二工作状态，所述第二探测模块(160)在探测过程中与所述笔形束(N2)相对位置固定。
  20. 一种利用权利要求1至18中任一项所述的辐射检查系统(100)检查被检查对象的辐射检查方法，其特征在于，包括：使所述射束调制装置处于第一工作状态，使用所述扇形束(N2)扫描所述被检查对象，确定需精确检查的嫌疑区域；使所述射束调制装置处于第二工作状态，使用所述笔形束(N3)对所述嫌疑区域进行精确检查。
  21. 根据权利要求20所述的辐射检查方法，其特征在于，所述辐射检查系统(100)包括第一探测模块(140)和能量分辨率高于所述第一探测模块(140)的第二探测模块(160)，所述辐射检查方法包括：在所述第一工作状态，所述第一探测模块(140)单独探测，或者，所述第一探测模块(140)与所述第二探测模块(160)同时探测，以确定所述嫌疑区域；在所述第二工作状态，所述第二探测模块(160)单独探测，或者所述第一探测模块(140)与所述第二探测模块(160)同时探测，以对所述嫌疑区域进行精确检查。
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Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107209282B (zh) 2014-11-20 2019-12-20 爱康公司 X射线扫描系统和方法
US10770195B2 (en) 2017-04-05 2020-09-08 Viken Detection Corporation X-ray chopper wheel assembly
CN109521486A (zh) * 2019-01-04 2019-03-26 同方威视技术股份有限公司 辐射检查设备
US11681068B2 (en) 2020-06-02 2023-06-20 Viken Detection Corporation X-ray imaging apparatus and method
CN113075241A (zh) * 2021-04-01 2021-07-06 中国原子能科学研究院 中子成像和x射线成像系统、方法以及装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104584137A (zh) * 2012-07-05 2015-04-29 美国科技工程公司 角度可变的准直器
US20150162658A1 (en) * 2013-12-10 2015-06-11 Elwha Llc Surface scattering reflector antenna
US20150372389A1 (en) * 2014-06-20 2015-12-24 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Modulation patterns for surface scattering antennas
CN106572823A (zh) * 2014-07-15 2017-04-19 皇家飞利浦有限公司 投影数据采集装置
CN106604762A (zh) * 2014-08-01 2017-04-26 凤凰医疗有限公司 用于强度调制离子射束治疗中的快速光栅射束扫描的方法和设备
CN107073284A (zh) * 2014-06-17 2017-08-18 直觉疗法股份公司 用于辐射逆向治疗计划的系统和计算机程序产品
CN107427691A (zh) * 2015-02-11 2017-12-01 优瑞技术公司 用于磁共振引导的辐射治疗的规划和控制

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE28544E (en) * 1971-07-07 1975-09-02 Radiant energy imaging with scanning pencil beam
JPH0512424A (ja) * 1991-07-05 1993-01-22 Toshiba Corp 散乱線断層画像撮影装置
US5493596A (en) * 1993-11-03 1996-02-20 Annis; Martin High-energy X-ray inspection system
US6269142B1 (en) * 1999-08-11 2001-07-31 Steven W. Smith Interrupted-fan-beam imaging
US6272206B1 (en) * 1999-11-03 2001-08-07 Perkinelmer Detection Systems, Inc. Rotatable cylinder dual beam modulator
US7103137B2 (en) * 2002-07-24 2006-09-05 Varian Medical Systems Technology, Inc. Radiation scanning of objects for contraband
CN101576513B (zh) * 2008-05-09 2011-12-21 清华大学 利用前向散射辐射检查物体的方法及其设备
US10393915B2 (en) * 2010-02-25 2019-08-27 Rapiscan Systems, Inc. Integrated primary and special nuclear material alarm resolution
CN103808739B (zh) * 2014-01-20 2016-06-22 北京睿思厚德辐射信息科技有限公司 一种透射成像和背散射成像一体化的安全检查装置
CN103997839B (zh) * 2014-06-06 2018-03-30 同方威视技术股份有限公司 一种准直可调制的x射线发生器
US10151716B2 (en) * 2015-08-06 2018-12-11 Georgetown Rail Equipment Company System and method for internal inspection of rail components
CN106841249A (zh) * 2017-04-12 2017-06-13 北京君和信达科技有限公司 透射式辐射成像系统
CN207816856U (zh) * 2017-12-26 2018-09-04 清华大学 辐射检查系统

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104584137A (zh) * 2012-07-05 2015-04-29 美国科技工程公司 角度可变的准直器
US20150162658A1 (en) * 2013-12-10 2015-06-11 Elwha Llc Surface scattering reflector antenna
CN107073284A (zh) * 2014-06-17 2017-08-18 直觉疗法股份公司 用于辐射逆向治疗计划的系统和计算机程序产品
US20150372389A1 (en) * 2014-06-20 2015-12-24 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Modulation patterns for surface scattering antennas
CN106572823A (zh) * 2014-07-15 2017-04-19 皇家飞利浦有限公司 投影数据采集装置
CN106604762A (zh) * 2014-08-01 2017-04-26 凤凰医疗有限公司 用于强度调制离子射束治疗中的快速光栅射束扫描的方法和设备
CN107427691A (zh) * 2015-02-11 2017-12-01 优瑞技术公司 用于磁共振引导的辐射治疗的规划和控制

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