Patent Description:
X-ray backscatter imaging is getting more and more important in security inspection because it can well detect the material of an object with a low atomic number. An embodiment is as follows: a flywheel rotates about a radiation source to form a pencil beam, and the pencil beam interacts with an inspected object to form a flying spot through Compton scattering. A back-scatter detector collects X-ray backscatter rays of the flying spot at any time, and after processing, information of the material is obtained, i.e., a backscatter image is formed. After continuous scanning, internal information of the whole object inspected can be processed and obtained, and objects with a lower atomic number, e.g., contraband goods such as explosives, drugs, hidden in concealed locations such as vehicle door interlayer, vehicle bottom, could be highlighted.

The existing flying point device operates as follows: a radiation source generates fan-shaped X-rays that pass through a rotating shield with multiple collimating holes to continuously generate a pencil beam for achieving a first dimensional scanning, and achieving a second-dimensional scanning by rotating or translating the rays to scan sectors.

However, if objects with different sizes are lined up, and the existing backscatter device is stationary in its scanning angle and scanning position including vertical and horizontal position, the view angle of the image is possibly bad, such that occlusion or overlap is formed between internal structures of the inspected objects, and suspicious goods cannot be highly identified under this angle.

<CIT> describes an X-ray backscattering safety inspection system, which including a control subsystem configured to adjust a distance between the backscattering inspection subsystem and the object to be inspected according to a size of the object to be inspected.

<CIT> describes an inspection system, which use an X-Y translation stage and electronically-steered X-ray source to create in effect both horizontal and vertical scanning to generate a backscatter X-ray image.

<CIT> describes a covert mobile inspection vehicle which can detect the distance of the detector from the surface of the object, and use the distance to solve the problem of image distortion.

<CIT> describes a system and method for standoff detection of human carried explosives, which can change the emitting angle at an angle horizontally upwards according to the movement of the inspected object.

<CIT> describes a system for imaging inspection of a movable object, which inspects whether a moving object to be inspected moves into a passage or not, and inspects whether a part to be shielded of the moving object passes into the passage or not, and generates a control signal for controlling the emitted radiating beams from the scan imaging device.

<CIT> describes a method and apparatus combining Gamma Resonance Absorption, Gamma Resonance Fluorescence, Gamma Induced Photofission, Dual Beam Gamma Energy Absorptiometry modality in a single system for contraband detection/identification, so that to simultaneous detection of multiple target objects in a single scan.

This article describes a scanner which is capable of safely maneuvering into and out of spaces that would be difficult for a conventional vehicle.

<CIT> describes a backscatter inspection system which include arms that maneuver a scan head with at least several degrees of freedom, and the scan head of the system can be moved to detect objects.

<CIT> describes a self-contained mobile inspection system, which inspecting receptacles and/or cargo containers using a single boom placed on a turntable with pivot points to allow for folding and unfolding of the boom. The radiation source is located in an end of the boom.

An object of this invention is to provide a security inspection approach that can flexibly adjust the position of the ray source according to the condition of the inspected object.

According to the invention, a security inspection apparatus is provided according to claim <NUM>, and a security inspection method is provided according to claim <NUM>.

Such a security inspection apparatus can detect size and position information of the inspected object, and automatically adjust the orientation of the radiation emitting device according to the size and position of the inspected object, thereby reducing or avoiding detection dead angles, and improving accuracy of the detection.

In this way, we can detect size and position information of the inspected object, and automatically adjust the orientation of the radiation emitting device according to the size and position of the inspected object, thereby reducing or avoiding detection dead angles, and improving accuracy of the detection.

The accompanying drawings illustrated herein provide further understandings to the invention and constitute a portion of the present application. The illustrative embodiments of the invention and their descriptions are used for explaining the invention and do not constitute improper definitions to the invention.

The present invention will be further illustrated below in details in conjunction with the accompanying drawings with exemplary embodiments. It is to be understood that the following Detailed Description is merely exemplary, rather than to limiting the present invention inappropriately.

The existing X-ray inspection apparatus cannot make real-time adjustments according to the size and position of the inspected object since components thereof have relatively fixed positions, which possibly will result in a poor effect of the backscatter scan image: for example, if the ray emission position is fixed, the view angle of the output image perhaps will be bad, and internal structures form occlusion or overlap, and suspicious objects cannot be well identified.

<FIG> is a schematic diagram of the security inspection apparatus according to one embodiment of this invention. The radiation emitting device <NUM> is capable of emitting rays <NUM> to an inspected object <NUM>. The back-scatter detector is capable of acquiring backscatter rays and generating backscatter data. The security inspection apparatus further comprises a size-distance detecting device <NUM> located between the radiation emitting device <NUM> and the inspected object <NUM>. The size-distance detecting device <NUM> is capable of detecting a size of the inspected object <NUM> and a distance from the inspected object <NUM>. The orientation adjusting device <NUM> is capable of adjusting the orientation of the radiation emitting device according to the size of the inspected object <NUM> and the distance between the inspected object <NUM> and the size-distance detecting device <NUM>. As shown by the dotted lines in <FIG>, the orientation adjusting device can adjust height, emission angle, and etc. of the radiation emitting device. For example, when it is detected that the inspected object is high, reduce the height of the radiation emitting device, and emit ray beams at an angle horizontally upwards; when it is detected that the inspected object is low, raise the height of the radiation emitting device, and emit ray beams at an angle horizontally downwards; when it is detected that the distance between the inspected object and the size-distance detecting device is fare, the decrease the distance between the radiation emitting device and the size-distance detecting device; when it is detected that the distance between the inspected object and the size-distance detecting device is near, increase the distance between the radiation emitting device and the size-distance detecting device.

In an embodiment, the back-scatter detector may be arc-shaped, and such a security inspection apparatus can better receive backscatter rays to thereby generate better backscatter data.

In one embodiment, the orientation adjusting device can adjust the angle of the back-scatter detector according to the orientation of the radiation emitting device. As shown in <FIG>, when the radiation emitting device <NUM> is adjusted to the orientation of the radiation emitting device <NUM> shown by the dotted lines on top of the figure, the back-scatter detector is adjusted to an angle of the back-scatter detector 2shown by the dotted lines in a lower portion; when the radiation emitting device <NUM> is adjusted to the orientation of the radiation emitting device <NUM> shown by the dotted lines on the bottom of the figure, the back-scatter detector is adjusted to an angle of the back-scatter detector 2shown by the dotted lines in a upper portion; when the radiation emitting device <NUM> is in the position shown by the middle solid lines, the back-scatter detector is adjusted to an angle of the back-scatter detector <NUM> drawn by the middle solid lines.

Such a security inspection apparatus can adjust the orientation of the radiation emitting device according to the position and size of the inspected object, and can adjust the angle of the back-scatter detector according to the orientation of the radiation emitting device, thereby better receiving backscatter rays to acquire more accurate and complete backscatter data.

In one embodiment, a schematic diagram of the radiation emitting device <NUM> of the security inspection apparatus is shown in <FIG>. A ray source <NUM> can emits X-rays <NUM>; a fixed shielding plate <NUM> is capable of restricting the rays <NUM> to be emitted in a fixed direction with a fixed angle; arotatingshield13 has at least one hole <NUM>. The rotating shield <NUM> rotates continuously, and when the hole <NUM> reaches the emission range of the rays <NUM> restricted by the fixed shielding plate <NUM>, the rays are emitted through the hole <NUM> to form a flying spot beam.

In such a security inspection apparatus, the radiation emitting device can emit rays with a predetermined frequency and angle, which facilitates adjustment and control as needed.

In the presently claimed invention, the size-distance detecting device comprises a plurality of sensors for determining a height of the inspected object by judging a height of an obstacle in front of the sensors. In one embodiment, the size-distance detecting device has a column of sensors that can judge a height of the inspected object by judging that in front of which sensors there are obstacles.

Such a security inspection apparatus can determine the size of the inspected object by existed and easily assembled equipments, and thus has a low cost and is easily promoted and applied.

In the presently claimed invention, there is a camera which can acquire a video image of the inspected object. An embodiment of the view angle of the video image is shown in <FIG>. Based on the video image, an image distance d between the inspected object and the size-distance detecting device, and an image height h of the inspected object can be acquired. Since the sensor can be utilized for acquiring an actual height H of the inspected object, as shown in <FIG>, the object on the left side is the security inspection apparatus, and the object on the right side is the inspected object. The actual distance between the inspected object and the size-distance detecting device is D. The actual distance D between the inspected object and the camera is determined from the formula: <MAT>.

It can be regard as the distance between the inspected object and the size-distance detecting device.

Such a security inspection apparatus can acquire the size of the inspected object, and the distance from the size-distance detecting device by cleverly using the sensors and the camera in combination with data analysis, thereby providing data for adjusting the orientation of the radiation emitting device and the angle of the back-scatter detector.

In one embodiment, there is a 3D camera in the vicinity of the sensor, which can directly acquire the distance information between the inspected object and the camera. Such an apparatus has a simpler construction, and response speed of the security inspection apparatus is increased since operations of calculation are omitted.

In one embodiment, a plurality of gears can be set according to actual size requirements of the inspected object, each gear for detecting inspected objects in a corresponding predetermined size range. In an embodiment, the inspected object may be a vehicle. Since the size of vehicles is relatively fixed, and can be classified as three kinds, namely full size vehicle, midsize vehicle and compact size vehicle, the gears of the radiation emitting device <NUM> and the back-scatter detector <NUM> can be set according to the vehicle's size. As shown in <FIG>, three gears a, b, c can be set, wherein the gear b is a reference gear in which the radiation emitting device is in the middle and shoots in the horizontal direction; the radiation emitting device at the gear a is located about <NUM> above the reference gear position and emits rays horizontally downwards at a <NUM> degree angle; the radiation emitting device at the gear c is located about <NUM> under the reference gear position, and emits rays horizontally upwards at a <NUM> degree angle.

A compact size vehicle can use the gear a, a midsize vehicle can use the gear b, and a full size vehicle can use the gear c. The position and angle of the radiation emitting device <NUM> and the back-scatter detector <NUM> at respective gears can be determined from the size of the inspected vehicle. Such a security inspection apparatus can adjust the orientation of the radiation emitting device and the angle of the back-scatter detector according to the predetermined gears, and thus has advantages such as lower requirement on the apparatus, faster response speed, and is easily promoted and applied.

In an embodiment, after acquiring the height of the inspected object, and the distance between the size-distance detecting device and the inspected object, an ideal height of the radiation emitting device and an ideal emission angle can be calculated based on a predetermined strategy, and the radiation emitting device can be adjusted to be in the ideal height, and emit rays with the ideal angle. Such a security inspection apparatus is adapted to the detection of various sizes of the inspected objects, and can adjust the radiation emitting device according to the ideal height and angle to detect the inspected object, thereby obtaining more accurate detection data and reaching a better detection effect.

In an embodiment, a plurality of gears can also be set for the distance between the radiation emitting device and the size-distance detecting device to adjust the horizontal orientation of the radiation emitting device. Since viewed from the principle of back-scatter detection, the closer the radiation emitting device is to the inspected object, the better the effect is. However, since the radiation angle of the radiation emitting device is limited, the distance between the radiation emitting device and the inspected object should be closer under the premise that the radiation angle covers the area to be inspected, and this distance is the ideal detection distance between the radiation emitting device and the inspected object.

If the ideal detection distance between the radiation emitting device and the inspected object is D1, and the distance between the size-distance detecting device and the inspected object is D, then the ideal distance between the radiation emitting device and the size-distance detecting device is D1-D, so a gear in which the distance between the radiation emitting device and the size-distance detecting device is closest to D1-D is selected, and the radiation emitting device is adjusted to the corresponding gear position. For example, three gears a, b, c are set for the distance between the radiation emitting device and the size-distance detecting device, the distance between the radiation emitting device and the size-distance detecting device is <NUM>, <NUM>, 75cmrespectively. According to the size of the inspected object, it is determined that the ideal distance between the inspected object and the radiation emitting device is <NUM>, and the distance between the inspected object and the size-distance detecting device is <NUM>, so it is needed to adjust the distance between the size-distance detecting device and the radiation emitting device to be <NUM>, then the radiation emitting device is adjusted to be in the position of gear a.

Such a security inspection apparatus can adjust the distance between the radiation emitting device and the size-distance detecting device according to the distance between the inspected object and the size-distance detecting device, realize the adjustment of the distance between the radiation emitting device and the inspected object, which on one hand, optimizes the detection effect, and on the other hand, reduces the requirement on the distance between the security inspection apparatus and the inspected object, such that the security inspection process is more convenient and feasible.

In an embodiment, it can be calculated according to the ideal detection distance D1 between the radiation emitting device and the inspected object, and the distance D between the size-distance detecting device and the inspected object that, the ideal distance between the radiation detecting device and the size-distance detecting device is D1-D, thereby adjusting the distance between the radiation emitting device and the size-distance detecting device as the ideal distance. For example, it is determined according to the size of the inspected object that the ideal distance between the inspected object and the radiation emitting device is <NUM>, and the distance between the inspected object and the size-distance detecting device is <NUM>, so it is needed to adjust the distance between the radiation emitting device and the size-distance detecting device to be <NUM>, and then the radiation emitting device is adjusted to be located at a distance of <NUM> from the size-distance detecting device.

Such a security inspection apparatus can adjust the orientation of the radiation emitting device according to the ideal distance between the radiation emitting device and the size-distance detecting device, which further optimizes the detection effect.

<FIG> is a schematic diagram showing the security inspection apparatus according to a further again embodiment of the invention. The security inspection apparatus further comprises a transportation facility <NUM> for carrying and moving the security inspection apparatus, which has the following advantages: facilitating transportation and flexible scheduling directed to emergencies; occupying a smaller area; continuously detecting a plurality of inspected objects by moving the security inspection apparatus in case where the inspected objects are inconvenient to be moved; easy use and convenient promotion and application.

In one embodiment, the security inspection apparatus further comprises a processor for receiving detection signals from the back-scatter detector, generating backscatter detection images, analyzing the inspected object and generating the detection result. Such a security inspection apparatus can obtain the detection image and the detection result in real time, which improves the detection efficiency.

In one embodiment, the security inspection apparatus further comprises a control device. An operator can manually adjust the position of the radiation detecting device and the angle of the back-scatter detector with the control device. By using such a security inspection apparatus, the operator can adjust the radiation detecting device and the back-scatter detector from multiple angles and positions according to detection needs, which is helpful to the identification of suspicious objects and improves accuracy of the detection.

<FIG> is a flowchart showing the security inspection method according to an embodiment of the invention.

In step <NUM>, the size-distance detecting device acquires a height of the inspected object and a distance between the inspected object and the size-distance detecting device.

In step <NUM>, the orientation of the radiation emitting device is adjusted according to the height of the inspected object and the distance between the inspected object and the size-distance detecting device. For example, when it is detected that the inspected object is high, reduce the height of the radiation emitting device ,and emit ray beams at an angle horizontally upwards; when it is detected that the inspected object is low, raise the height of the radiation emitting device, and emit ray beams at an angle horizontally downwards; when it is detected that the distance between the inspected object and the size-distance detecting device is fare, the decrease the distance between the radiation emitting device and the size-distance detecting device; when it is detected that the distance between the inspected object and the size-distance detecting device is near, increase the distance between the radiation emitting device and the size-distance detecting device.

In step <NUM>, the backscatter detection data is acquired by using a back-scatter detector.

In step <NUM>, a detection result is acquired based on the backscatter detection data.

<FIG> is a flowchart showing the security inspection method according to another embodiment of the invention.

In step <NUM>, a height of the inspected object and a distance between the inspected object and the size-distance detecting device are acquired by using a size-distance detecting device.

In step <NUM>, the orientation of the radiation emitting device is adjusted according to the height of the inspected object, and the distance between the inspected object and the size-distance detecting device.

In step <NUM>, an angle of the back-scatter detector is adjusted according to the orientation of the radiation emitting device. As shown in <FIG>, when the radiation emitting device <NUM> is adjusted to the orientation of the radiation emitting device <NUM> shown by the dotted lines on top of the figure, the back-scatter detector is adjusted to an angle of the back-scatter detector 2shown by the dotted lines in a lower portion; when the radiation emitting device <NUM> is adjusted to the orientation of the radiation emitting device <NUM> shown by the dotted lines on the bottom of the figure, the back-scatter detector is adjusted to an angle of the back-scatter detector 2shown by the dotted lines in a upper portion; when the radiation emitting device <NUM> is in the position shown by the middle solid lines, the back-scatter detector is adjusted to an angle of the back-scatter detector <NUM> drawn by the middle solid lines.

In step <NUM>, backscatter detection data is acquired by using a back-scatter detector.

In step <NUM>, a detection result is acquired based on the backscatter detection data. In this way, we can adjust the orientation of the radiation emitting device according to the position and size of the inspected object, and can adjust the angle of the back-scatter detector according to the orientation of the radiation emitting device, thereby better receiving backscatter rays to acquire more accurate and complete backscatter data.

In the presently claimed invention, a plurality of sensors may be utilized for determining a height of the inspected object by judging a height of an obstacle in front of the sensors. In one embodiment, the size-distance detecting device has a column of sensors that can judge a height of the inspected object by judging that in front of which sensors there are obstacles. Such a method can determine the size of the inspected object by existed and easily assembled equipments, and thus has a low cost and is easily promoted and applied.

In the presently claimed invention, a camera close to the sensor can be utilized for shooting in the direction of the inspected object, thus we can acquire a video image of the inspected object. And then a distance between the inspected object and the camera can be acquired according to the video image and the height of the inspected object determined by the sensor. As shown in <FIG>.

In step <NUM>, a height H of the inspected object is determined by judging a height of an obstacle in front of the sensor.

In step <NUM>, a camera shoots video image of the inspected object.

In step <NUM>, an image height h of the inspected object and an image distance d between the inspected object and the size-distance detecting device are acquired according to the video image.

In step <NUM>, the actual distance between the inspected object and the size-distance detecting device is D. The actual distance between the inspected object and the size-distance detecting device is determined from the formula: <MAT>.

In this way, we can acquire the size of the inspected object, and the distance from the size-distance detecting device by cleverly using the sensors and the camera in combination with data analysis, thereby providing data for adjusting the orientation of the radiation emitting device and the angle of the back-scatter detector.

In one embodiment, a plurality of gears can be set according to actual size requirements of the inspected object, each gear for detecting inspected objects in a corresponding predetermined size range. A corresponding gear can be determined from the size of the inspected object determined by the size-distance detecting device, and then the radiation emitting device is adjusted to the position and angle of the corresponding gear.

In an embodiment, the distance between the inspected object and the size-distance detecting device is D; determine the ideal distance D1 between the inspected object and the radiation emitting device based on the size of the inspected object ; and the ideal distance between the radiation emitting device and the size-distance detecting device is D1-D. A gear in which the distance between the radiation emitting device and the size-distance detecting device is closest to D1-D will be selected, and the radiation emitting device will be adjusted to the position and angle of the corresponding gear. In this way, a security inspection apparatus can adjust the distance between the radiation emitting device and the size-distance detecting device according to the distance between the inspected object and the size-distance detecting device, realize the adjustment of the distance between the radiation emitting device and the inspected object, which on one hand, optimizes the detection effect, and on the other hand, reduces the requirement on the distance between the security inspection apparatus and the inspected object, such that the security inspection process is more convenient and feasible.

In an embodiment, after acquiring the height of the inspected object, and the distance between the size-distance detecting device and the inspected object, an ideal height of the radiation emitting device and an ideal emission angle can be calculated based on a predetermined strategy, and the radiation emitting device can be adjusted to be in the ideal height, and emit rays with the ideal angle. In this way, a security inspection apparatus can adjust the radiation emitting device according to the ideal height and angle to detect the inspected object, thereby obtaining more accurate detection data and reaching a better detection effect.

In an embodiment, it can be calculated according to the ideal detection distance D1 between the radiation emitting device and the inspected object, and the distance D between the size-distance detecting device and the inspected object that, the ideal distance between the radiation detecting device and the size-distance detecting device is D1-D, thereby adjusting the distance between the radiation emitting device and the size-distance detecting device as the ideal distance.

In this way, we can adjust the orientation of the radiation emitting device according to the ideal distance between the radiation emitting device and the size-distance detecting device, which further optimizes the detection effect.

<FIG> is a flowchart showing the security inspection method according to a further embodiment of the invention.

In a step <NUM>, the inspected object passes through the detection area of the security inspection apparatus.

In a step <NUM>, the size-distance detecting device of the security inspection apparatus detects the size of the inspected object, and a distance between the inspected object and the size-distance detecting device.

In a step <NUM>, the security inspection apparatus adjusts the position and angle of the radiation emitting device and the angle of the back-scatter detector according to the size of the inspected object, and the distance between the inspected object and the size-distance detecting device. The radiation emitting device emits flying point rays to the inspected object and the back-scatter detector receives the backscatter rays.

In a step <NUM>, detection data is acquired through the back-scatter detector. The detection image can be displayed according to the backscatter data to determine the detection result.

In this way, we can adjust the orientation of the radiation emitting device and the angle of the back-scatter detector in real time according to the size and distance from the inspected object, and achieve fast detection of the inspected object; while optimizing the detecting effect, we can continuously scan a plurality of the inspected objects, which can increase throughput of the inspected objects, improve the detection speed and guarantee the detection efficiency.

<FIG> is a flowchart of the security inspection method according to a further again embodiment of the invention.

In a step <NUM>, the detection data can be acquired in the way shown in the embodiment of <FIG>.

In a step <NUM>, a suspicious area is determined from the acquired detection data. The suspicious area may comprise an unidentifiable area, a detection dead angle or a suspicious contraband object area.

In a step <NUM>, the operator can pay attention to the detection of the suspicious area. In an embodiment, the operator adjusts the position and angle of the radiation emitting device and the angle of the back-scatter detector, to perform multiple scans on the suspicious area.

In a step <NUM>, by performing multiple scans on the suspicious area, multiple detection data is acquired.

In a step <NUM>, determine the detection result from the multiple detection data.

In this way, we can determine the suspicious area of the inspected object from the detection data of a single rapid detection, and then adjust the position and angle of the radiation emitting device and the angle of the back-scatter detector to pay attention to the detection of the suspicious area, thereby further optimizing the detection result.

Claim 1:
A security inspection apparatus comprising:
a radiation emitting device(<NUM>),
a back-scatter detector(<NUM>) located between the radiation emitting device(<NUM>) and an inspected object(<NUM>),
a size-distance detecting device(<NUM>) located between the radiation emitting device and the inspected object, for detecting a height of the inspected object and a distance from the inspected object,
an orientation adjusting device(<NUM>) for determining a direction and a height of the radiation emitting device according to the height of the inspected object and the distance between the inspected object and the size-distance detecting device, and adjusting the radiation emitting device according to the direction and the height determined;
characterized in that the security inspection apparatus further comprises: a camera, configured to shoot video image of the inspected object and the size-distance detecting device ;
the size-distance detecting device(<NUM>) comprises:
judging a height of an obstacle in front of the sensors
a calculating device configured to acquire an image height of the inspected object and an image distance between the inspected object and the size-distance detecting device in a video image shot by the camera, and
determine the distance between the inspected object and the size-distance detecting device from a ratio of the image distance to the image height and the height of the inspected object detected by the sensors.