MX2012010644A - Personnel screening system. - Google Patents

Abstract

The present specification discloses an inspection system for detecting objects being carried by a person who is moving along a pathway. The inspection system has two detection systems configured to detect radiation scattered from the person as the person moves along the pathway and an X-ray source positioned between the detection systems. The X-ray source is configured to generate a vertical beam spot pattern and does not generate beams that move horizontally.

Description

PERSONNEL INSPECTION SYSTEM FIELD OF THE INVENTION The invention relates generally to security systems for inspecting threats contained in people, and specifically, to a personnel inspection system comprising modular components for improved portability, and more specifically, to compact and portable sensor towers.

BACKGROUND OF THE INVENTION Radiation-based systems for screening people and in use today at transit points, such as airports, courthouses, etc., are generally portal systems that are bulky and are not conductive for portable applications. Unfortunately, such current art inspection systems are not compact enough (eg, they have back-end management cables and wires to connect the photomultiplier tubes to a centralized analog-to-digital conversion and power station) and they are often difficult and time consuming to use and / or transport.

Also, security systems are currently limited to their ability to detect contraband, weapons, explosives, and other dangerous objects hidden under clothing. Metal detectors and sniffer dogs are commonly used for the detection of large metal objects and certain types of explosives, however, there is a wide range of dangerous objects that can not be detected using these devices. Plastic and ceramic weapons increase the types of non-metallic objects that security personnel have to detect. The manual search of subjects is slow, inconvenient, and would not be well tolerated by the general public, especially as a standard procedure in high traffic centers, such as airports.

X-ray systems known in current art to detect hidden objects in people have limitations in their design and method that prohibit them from achieving low doses of radiation, which is a health requirement, or prevent the generation of high image quality, which they are prerequisites for commercial acceptance. An inspection system that operates at a low level of radiation exposure is limited in its accuracy by the small amount of radiation that can be directed toward a person being examined. The absorption and scattering of X-rays also reduces the amount of X-rays available to form an image of the person and any hidden object. In current art systems the low number of detected X-rays has resulted in poor image quality unacceptable.

This problem is even more significant if an X-ray inspection system is being used in open places such as stadiums, shopping centers, outdoor exhibitions and fairs, etc. In such places, people can be located both near and / or at a distance from the machine. If a person being scanned is not very close to the X-ray machine, the resulting image may not be clear enough because the amount of radiation that reaches the person is very low. This limits the scanning range of the system a few meters from the front of the machine. If, however, a person being scanned is too close to the X-ray machine, the amount of radiation that hits the person may not be safe.

Therefore, there is a need for a compact radiographic detector / source inspection system that has improved detection efficiency, that is lightweight and yet robust enough and can be easily disassembled for transport and then simple to assemble in one place . There is also a need for a radiographic inspection system that provides good resolution as well as wide range of vision and fast scanning speed, while maintaining radiation exposure within safe limits. That is, the system must not only be safe for people at short distances, but also provide good resolution and penetration at range distances.

BRIEF DESCRIPTION OF THE INVENTION In one embodiment, the present specification discloses an inspection system for detecting objects that are transported by a person, wherein said person moves along a plane defined by a Z axis and a Y axis, the inspection system comprising: a) a first detection system configured to detect radiation scattered by said person while the person moves along the Y axis of the plane, wherein said first detection system comprises a first flat surface positioned opposite the plane, and configured to generate electronic signals sensitive to the radiation detected; b) a second detection system configured to detect radiation scattered by said person while the person moves along the Y axis of the plane, wherein said second detection system comprises a second flat surface positioned opposite the plane, and configured to generate electronic signals sensitive to the radiation detected; c) a source of X-rays positioned between said first detection system and said second detection system, wherein said first X-ray source is configured to generate a beam point pattern along the Z axis of the plane and wherein said X-ray source does not generate beams that move along the Y axis of the plane; and d) a processing system for analyzing the electronic signals generated by the first detection system and the second detection system and for generating an image on a screen.

Optionally, the X-ray source is coupled to a beam tracker and wherein said beam tracker operates to produce a thin beam of X-ray scanning along the Z axis. The beam tracker does not produce a fine scanning beam along the Y axis. In one embodiment, the beam changer comprises a trocar wheel having three slits and wherein each slit is positioned 120 degrees apart from an adjacent slit. The slits are aligned with at least two parallel collimator slits and wherein the X-rays emitted from the X-ray source conically illuminate the slits of the collimator to generate at least two parallel scanning beams interspersed in time. In another embodiment, the beam tracker comprises a hollow cylinder having at least one helical aperture. The thin scanning beam has a linear scanning speed and wherein said linear scanning speed varies or remains constant when modifying the inclination and rotation of at least one of the helical openings. The fine scanning beam has a point size and wherein said point size varies or remains constant when modifying an aperture width of at least one of said helical apertures.

Optionally, the first detection system is contained within a first enclosure, wherein said first enclosure has a first width extending from one end of said first enclosure to an opposite end as said first enclosure and wherein the planar surface extends along the entire first width. The second detection system is contained within a second enclosure, wherein said second enclosure has a first width extending from one end of said second enclosure to an opposite end of said second enclosure and wherein the flat surface extends as far as possible. length of the entire first width. The first enclosure is physically separate from, and independent of, said second enclosure. The X-ray source is contained within a third enclosure where the third enclosure is physically separated from, and independent of, the first and second enclosures.

Optionally, each of the first, second, and third enclosures weigh less than 40 kg (88 pounds). The third enclosure can be detachably connected to the first enclosure and the second enclosure. Each of the first, second, and third enclosures may be detachably connected to a frame. The beam changer comprises a disk changer which is configured to be rotated by a motor. The speed of the tracker wheel is controlled dynamically by a controller to optimize a scanning speed of an X-ray beam. The first enclosure comprises a) a first side defined by a flat surface having an exterior surface facing the person and an inner surface, wherein the first side is configured to receive radiation scattered by the person; b) a second side in an acute angular relationship with said first side, wherein said second side is defined by a flat surface having an inner surface adapted to receive radiation passing through the first side and wherein said second side is configured to receive only radiation after it passes through said first side; c) a first substrate positioned on the inner surface of the first side, wherein the first substrate further comprises an active area for receiving and converting said radiation into light; d) a second substrate positioned on the inner surface of the second side, wherein the second substrate further comprises an active area for receiving and converting said radiation into light; and e) at least one photodetector having a light sensitive area and an area not sensitive to light, wherein the light sensitive area is positioned to receive the light emitted from the first substrate and the second substrate.

Optionally, the radiation comprises X-ray photons and wherein said first substrate detects 30-60% of the X-ray photons incident on said first side. The second substrate detects 10-30% of the X-ray photons that impinge on said first side. The inspection system further comprises a conveyor to enable a person standing or sitting to move along the plane. The generated image comprises 480 rows, 160 columns, and 8 bits per pixel. The X-ray source generates a beam point pattern along the Z axis of the plane when pivoting from a first point to a second point and wherein said pivot is centered around a predefined point of rotation. The X-ray source and a beam changer are coupled to a surface configured to tilt vertically relative to a guide member and in response to a motor.

In another embodiment, the present disclosure discloses a method for detecting threat objects hidden in a person's body by using an inspection system comprising at least one radiation source for producing a thin beam of X-ray scanning, wherein said The fine scanning beam has a trajectory, and a detector arrangement comprising at least one first detector enclosure having a first surface and a second detector enclosure having a second surface, the method comprising the steps of: a) making the person move by passing at least one radiation source in a plane perpendicular to the beam path of the scanning thin beam and parallel to said first surface and second surface; b) generating an X-ray beam within a radiation source enclosure, wherein the radiation source comprises an X-ray source coupled with a beam tracker and wherein the fine scanning beam is collimated by at least one slit in the enclosure of the radiation source to generate a vertical beam spot pattern and not a horizontal beam spot pattern; c) detecting radiation dispersed by the person in at least one of the first detector enclosure or second detector enclosure; and d) processing the detected radiation to generate a two-dimensional image, wherein said image shows any hidden explosive material being transported by the person.

Optionally, the beam tracker comprises a trocar assembly having a hollow cylinder with helical slits extending along a length of the cylinder, a cylinder of carbon fiber covering the hollow cylinder, and a cylinder of epoxy polyethylene that covers the carbon fiber cylinder. The assembly of the trocador is rotated by a magnetic support assembly comprising a magnetic rotor and a magnetic support stator and wherein the magnetic support assembly provides magnetic levitation for the trocar assembly at least during the on and off states of the beam changer.

Optionally, the X-ray source is coupled to a vertical lifting mechanism wherein said lifting mechanism is coupled to a weight configured to counterbalance the X-ray source. The X-ray source is coupled to a vertical lifting mechanism where said lifting mechanism is coupled to at least one lifting strap. The X-ray source is coupled to a vertical lifting mechanism wherein said vertical lifting mechanism is coupled to a gear reducer and motor and wherein said lifting mechanism is not coupled to a counterbalancing weight.

In another embodiment, the present specification discloses a method for manufacturing inspection system, comprising: a) receiving at least one container, wherein said at least one container comprises a first detection system configured to detect radiation scattered by a person while the person moves along a path, wherein the first detection system is contained within a first enclosure; a second detection system configured to detect radiation scattered by the person while the person moves along the path, wherein the second detection system is contained within a second enclosure; an X-ray source positioned between said first detection system and said second detection system, wherein said X-ray source is configured to generate a vertical beam spot pattern and wherein the X-ray source is contained within a third enclosure having an angled left side and an angled right side; b) joining said first enclosure with the angled left side of the third enclosure; and c) joining said second enclosure with the angled right side of the third enclosure. In other words, the X-ray source is configured to generate a vertical beam point pattern and does not generate beams that move horizontally or configured in such a way that the source is restricted to generate a beam point that moves upwards and down (vertically) but does not move side by side (horizontally).

Optionally, the first, second, and third enclosures are each physically separated from, and independent of, the others. Each of the first, second, and third enclosures weighs less than 40 kg (88 pounds). Each of the first, second, and third enclosures are detachably connected to a frame.

As discussed in more detail later, the system can be configured with two systems opposed to each other and that define a gateway for a person to walk through and an inspection volume. In one embodiment, the enclosures of the detection system and the X-ray system are configured with hinged doors that open within the inspection volume and that do not open behind the systems, thus decreasing the required volume of the systems.

BRIEF DESCRIPTION OF THE DRAWINGS These and other features and advantages of the present invention will be appreciated, insofar as they are better understood with reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein: Figure 1 illustrates an exemplary X-ray backscattering system configuration, including a system and detection towers, for the inspection system of the present invention.

Figure 2A shows multiple views of the detector towers according to one embodiment of the present invention.

Figure 2B shows an exploded view of the photomultiplier tubes, mounting plate and signal processing board.

Figure 2C shows an exploded view of the structures covering the assembly of photomultiplier tubes, mounting plate and signal processing board within the detector tower.

Figure 2D shows a photomultiplier tube assembly according to an embodiment of the present invention.

Figure 2E shows a signal processing board according to an embodiment of the present invention.

Figure 2F shows the wire connections of four photomultiplier tubes with the signal processing board.

Figure 2G shows Table 1 comprising a first BOM set with reference to the corresponding item numbers marked in the views of Figures 2A to 2F.

Figure 2H shows Table 2 comprising a second BOM set with reference to the corresponding item numbers marked in the views of Figures 2A through 2F.

Figure 3A is a disassembled and packaged illustration of an exemplary modular X-ray backscattering system configuration, including a system and detection towers, for the personnel inspection system of the present invention.

Figure 3B is an assembled illustration of the exemplary modular X-ray backscattering system configuration shown in Figure 3A.

Figure 4 illustrates a detector tower spaced apart from the radiation housing for ease of service access to the modular components of the inspection system of the present invention.

Figure 5A illustrates a top view of an exemplary bail wheel that is used in the inspection system of the present invention.

Figure 5B illustrates an exemplary disk-changer assembly, with electromagnetic motor and integrated supports.

Figure 5C illustrates an X-ray source coupled to a disk changer, according to an embodiment of the present invention.

Figure 6A illustrates an X-ray source being used in conjunction with a trocar wheel in an exemplary threat detection system, further showing a "CAM" tilting mechanism coupled to a source.

Figure 6B shows a diagram of the metal frame CAM tilting mechanism 600 in an expanded view, further showing the driving wheel against a CAM arm, in such a way as to allow the vertical movement of the source.

Figure 6C illustrates another view of the module illustrated in Figure 6A, further showing a turntable for rotating the source and corresponding power supply.

Figure 7A is a mechanical illustration of an exemplary design of a modality of an example beam forming apparatus.

Figure 7B illustrates an exemplary beamforming apparatus with an X-ray source.

Figure 7C is a mathematical expression of the beam path using the rotary roller baler of the present invention with a single source, according to one embodiment.

Figure 8 illustrates another embodiment of the inspection system of the present invention, in use.

Figure 9A is an image obtained from using a segmentation algorithm according to an embodiment of the present invention.

Figure 9B is an image obtained from using a segmentation algorithm according to an embodiment of the present invention.

Figure 9C is a close view of the segmented object of the image shown in Figure 9B using a segmentation algorithm according to an embodiment of the present invention.

Figure 10A is an image obtained using a segmentation algorithm according to an embodiment of the present invention.

Figure 10B is an image obtained using a segmentation algorithm according to an embodiment of the present invention.

Figure 11 is a side view diagram illustrating vertical scanning using a single source of radiation.

Figure 12 shows the top view of an exemplary scanning arrangement that is used in the present invention.

Figure 13 illustrates an exemplary source arrangement, having dual wheels and a flight aperture for range selection.

Figure 14 illustrates an exemplary bail wheel that can be used in the dual wheel system described with respect to Figure 13.

Figure 15 is another view of the upper part of the vertical scanning system described with respect to Figure 11, which further illustrates a flight aperture according to an embodiment of the present invention.

Figure 16 illustrates an exemplary arrangement for a dual view, quadratic range system according to one embodiment of the present invention.

Figure 17 illustrates the response of two detectors to a radiation beam that traverses through an object.

DETAILED DESCRIPTION OF THE INVENTION This specification is addressed to personnel inspection systems that comprise modular components, including detector and source units. The modular components of the present invention allow for a generally compact, lightweight and yet robust structure that can be disassembled for easy transportation and is also simple to assemble at a site required for inspection. The new modular architecture of the inspection system of the present invention also allows the modular components to be manufactured separately and to be quickly assembled for assembly. Similarly, the modular components can be easily disassembled for easy service access to the selective components and / or for packaging for later transport.

The present specification is also an improved method for inspecting individuals in safety locations without exposing individuals to high radiation and retaining the efficiency of the inspection process. The system that is disclosed allows the maximum performance of threat detection and image clarity regardless of the distance of the individuals of the inspection system.

In one modality, a radiographic image is formed using any available radiation imaging techniques for "body imaging" such as, but not limited to, scattering of X-rays, infrared images, millimeter wave images, RF images, radar images , holographic images, CT images, and MRI. Any system of "body images" that has the potential to show body details can be employed. In one embodiment, any photodetectable radiation or any source of radiation with a light beam can be employed in the present invention.

In one embodiment the system of the present invention requires that a subject under inspection assumes only one position and uses a single source with a single group of detectors, circuits and processor to generate two separately processed scanning beams and associated images.

In one embodiment, the system of the present invention is an inspection system of walking through it that uses a single source with a single group of detectors, circuits and processor to generate two separately processed scanning beams and associated images.

In another mode, the system operates in a dual source mode but uses a single group of detectors, circuits and processor.

The system allows the detection of threats through efficient generation of images of explosive materials such as dynamite, C-4, as well as ceramics, graphite fibers, plastic containers, plastic weapons, glass jars, syringes, packaged narcotics, paper bundles currency, and even wooden objects.

In X-ray backscatter systems to detect hidden objects, a thin beam of X-rays passes through the body surface of a person being examined. X-rays that are scattered or reflected from the body of the subject are detected by a detector such as, for example, a combination of scintillator and photomultiplier tube. The resulting signal produced by the X-ray detector is then used to produce an image of the body, such as a silhouette, of the subject and any hidden object carried by the subject.

In one embodiment, the X-ray backscattering image generation system of the present invention is designed in such a way that it is used for almost real-time image generation of people or objects with a beam of questioning radiation while they are in motion. . The system is also capable of automatically detecting threats by processing detection algorithms in the image data almost in real time.

The present invention is directed to multiple modalities. The following disclosure is provided in order to enable a person skilled in the art to practice the invention. The language used in this specification should not be interpreted as a general rejection of any specific modality or to limit claims beyond the meaning of the terms used in this document. The general principles defined in this document can be applied to other modalities and applications without departing from the spirit and scope of the invention. Also, the terminology and phraseology that is used for the purpose of describing exemplary modalities should not be considered as limiting. Therefore, the present invention should be granted the broadest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For the purpose of clarity, the details related to the technical material known in the technical fields related to the invention have not been described in detail so as not to obscure the present invention unnecessarily.

Figure 1 illustrates an exemplary X-ray backscattering system configuration for the new modular inspection system 100 of the present invention. With reference to Figure 1, an X-ray source 160 is enclosed in a modular housing 165 and is used to generate a narrow thin X-ray beam 102 directed toward the subject under inspection 103.

In one embodiment, the thin beam 102 is formed with the integration of X-ray tubes and a beam changer mechanism 167. The thin beam 102 is scanned either horizontally or vertically through the subject. This tracking is the result of the beam changer mechanism by allowing only a minimum exit opening for the X-ray beam to be projected. If a tracker wheel is used, as described below, the outlet opening is 1 mm in diameter resulting in an X-ray beam that has deviated by about 7 mm. In one embodiment, subject 103 is a human.

While the target (person being scanned) 103 poses in front of or walks through the inspection system 100, the resulting fine beam 102 reaches the target, whereby at least a portion of the X-rays are backscattered. Exemplary embodiments of the mechanism beam changer 167 are described in greater detail below.

It should be understood by those skilled in the art that any number of ionization radiation sources can be used, including but not limited to gamma radiation, electromagnetic radiation, and ultraviolet radiation. Preferably the X-ray energies employed are between 30 kV and 100 kV.

In one embodiment, sensors 104a and 104b are used to detect the presence of a person posing in front of or walking through the inspection system.

At least a portion of the scattered X-rays 105 impinges on the detector array 106. In one embodiment, the detector array 106 in the inspection system of the present invention comprises first and second detector enclosures 110 and 120 for enabling detection. In one embodiment, the first and second detector enclosures 110 and 120 are modeled in the form of modular detector towers, comprising at least one scintillator screen. In another embodiment, the first and second detector enclosures 110 and 120 are modular detector towers comprising at least two detector screens. In alternate embodiments, the detector enclosures may comprise any number of arrangements including, but not limited to, a plurality of detector screens. In U.S. Patent Application No. 12 / 262,631, entitled "Multiple Screen Detection System", and assigned to the applicant of the present invention, it is incorporated herein by reference. In addition, U.S. Provisional Patent Application No. 61 / 313,733, entitled "Multiple Screen Detection Systems," and filed on March 14, 2010, is hereby incorporated by reference. reference in its entirety.

As shown in Figure 1, the detector towers 110 and 120 each comprise the first side area 141, second side area 142, and third side area 143 that are connected therebetween at an angle to form a triangular cross section. The first side area 141 comprises the screen 147 and facing the subject 103 under inspection. The second side area 142 comprises a second screen 148 inside the towers. In one embodiment, screens 147, 148 are relatively thick CaW04 scintillator screens having a relatively short decay time of 10 microseconds which allows rapid scanning of the radiation beam with no image degradation. The CaW04 screen, in one modality, is capable of detecting approximately 70% of the backscattered or transmitted radiation, and therefore, produces approximately 250 pho of light usable by 30 keV of X-rays. Additionally, the use of a screen thicker enables the detection of more of the radiation that hits the detector at the cost of less light output. In one embodiment, the density of the screen area is 80 milligrams per square centimeter.

In one embodiment, to secure the detector towers to the base, large diameter shoulder bolts are pre-fastened to the base, so that the detector towers can be "twisted" and secured on the base. Once the radiation source and housing are attached to the base, the detector towers can not be moved or untwisted. The radiation accommodation area 165 comprises the first angled side 170 and the second angled side 171 such that they easily abut and coincide with the sides 142 of the detector towers 110 and 120, when the detector towers and the source housing of radiation are integrated or assembled together. A tape of the user side 172 facing the subject 103 comprises an aperture 173 through which the x-ray beam 102 passes before striking the subject 103. The limited aperture 173 aids in the reduction of electromagnetic interference and radiation noise . The side tape 172 also acts as a separator for the two detector towers such that the two detector towers are assembled symmetrically around the incident X-ray fine beam 102 to detect the backscattered X-rays 105 and provide an electronic signal characteristic of the reflectance of the X-rays In one embodiment, the detector towers 110 and 120 are spaced apart by the ribbon 172 such that the bait wheel or other beam collimation means is in the middle of the two towers. The two towers 110, 120 are separated by a distance "d", which in a mode ranges from 1/2 to twice the diameter of the trocar wheel. The distance "d" defines the field of view of the X-ray source and is optimized for a sufficient field of vision while preventing the overexposure of the detectors.

In accordance with one embodiment of the present invention, the detector towers 110, 120 and radiation housing 165 are composite walls or any other similar non-conductive material evident to those skilled in the art that provide optimization of a generally robust structure and still light. Specifically, housing the management electronics, wires and cables associated with the photomultipliers and the radiation source within the composite walls creates a Faraday cage, substantially reducing electromagnetic interference.

In one embodiment of the present invention, the detector towers 110, 120 also comprise lighting means, such as LEDs, at the periphery or any of the edges of the front area 141 for illumination which represents that the inspection system is on and / or the inspection is in process. Each of the towers 110, 120 comprises photomultiplier tubes 150 which are placed inside the towers, next to the third lateral area 143. The administration electronics of the photomultiplier tubes 150 is housed in the substantially semicircular housing 151.

Figures 2A to 2F show structural details of the detector towers according to a specific embodiment of the present invention. Figures 2G and 2H show the list of materials with reference to the corresponding item numbers marked in the views of Figures 2A to 2F. Specifically, Figure 2A shows perspective views of identical detector towers 210 and 220 together with their respective front views 205, top view 215 and side view 216. In one embodiment, the towers have a height "h" of 170.2 cm (67 inches) ), lateral width "w" of 76.2 cm (30 inches) and maximum thickness "t" of 40.6 cm (16 inches).

Now with reference to the exploded views of the detector towers in Figures 2B and 2C, simultaneously, the mounting plate 225 is shown as "detached" and separated from the four photomultiplier tube assemblies 230 that are mounted on the plate 225 when they are assembled According to one embodiment of the present invention, the administration electronics of the photomultiplier tubes 230 comprise a signal processing board 235 co-located on the mounting plate 225 in proximity to the photomultiplier tubes. Figure 2D provides a more detailed view of the photomultiplier assembly 230 while Figure 2E shows a detailed view of the signal processing board 235 which in this embodiment is a four channel card corresponding to the four photomultiplier tubes.

At least one analog-to-digital conversion card and a power supply module are mounted on the signal processing board 235. The power supply module applies an operating voltage to the photomultiplier tubes while the conversion card analog to digital converts the pulse current out of the photomultiplier tubes into digital signals for further processing. Conventionally, massive cables are used to connect the photomultiplier tubes with a central analog-to-digital converter and power station located at a distance from the photomultiplier tubes. By having the power supply as well as the analog-to-digital converter near the photomultiplier tubes, smaller wires are needed, thus also reducing the transient signal noise and improving the overall signal-to-noise ratio (SNR, Signal to Noise). Reduction). Similarly, Figure 2F shows the wire connections of the four photomultiplier tubes 230 with the signal processing board 235.

With reference again to FIGS. 2B and 2C, simultaneously, a seal 226 allows the assembly comprising the mounting plate 225, the photomultipliers 230 and the signal processing board 235 to fit closely in the corresponding tower premise 227. A cover set of interconnectable structures both protects and allows easy access when necessary to the photomultiplier tubes located in the assembly of the mounting plate. This set of structures comprises a corner cover 240 with a connector corner cover 241; a closure cover 245 with a corresponding connector 246; two side adjustment plates 250 and upper and lower handle frames 255.

Referring again to Figure 1, in one embodiment, the inspection system 100 has modular components that can be disassembled for mobility and ease of transport and reassembled at the site of interest. Therefore, the tear-shaped detector towers 110, 120 and the radiation source housing 165 with the associated electronics and cables are manufactured as separate modules or cabinets that can be quickly integrated to form the system 100. The new modular architecture in the form of tear enables a system 100 in general compact and light.

Figure 3A shows a disassembled view 300a of the inspection system of the present invention in such a way that its modular components, such as the sensor towers 310, 320 together with the radiation source housing 365, are disassembled and packaged for ease of transport . For example, the triangular cross section of the detector towers 310, 320 enables them to be packed supported between them in a way that requires minimal space for transport. Figure 3B shows an assembled view 300b of the inspection system that has been constructed from the transportable package 300a of Figure 3A. The modular components or cabinets of the inspection system of the present invention are designed in such a way that they have simple and intuitive connection points, in such a way that they are capable of being fastened to each other, by means of adjustment buttons, for their rapid assembly. In one modality, it takes less than 30 minutes to assemble / deploy the inspection system from its transportable, packaged condition. In one mode, it takes approximately 15 to 30 minutes to assemble / deploy the inspection system from its transportable, packaged condition. In one embodiment, the assembly / deployment time depends on whether the unit should be heated or cooled to bring the unit to safe operating temperatures.

Those skilled in the art should appreciate that the design of the modular components of the inspection system of the present invention also facilitates ease of service access for repair and maintenance. For example, Figure 4 shows an assembled / deployed view 400 of the inspection system of the present invention with the detector tower 410 removed from the radiation housing 465 for service access to the housing 465 and / or for selective tower repair and maintenance. 410 In one embodiment of the present invention, in order to obtain 2D images of scattered radiation, the detector systems make use of a dual axis scanning beam. With reference again to Figure 1, during operation, while the subject 103 walks by or stops in front of the detector towers 110, 120 a part of the thin X-ray beam 102 striking the subject 103 is backscattered, as rays 105 to the Compton scattering and hits the first screen 147 in the front side area 141 of the detector towers. While a portion of the scattered X-rays are detected by the first screen 147, some portion of these is transmitted through the first screen 147 undetected and impinge on the second screen 148 (on the side 142) inside the the detector towers. In one embodiment, approximately 40% of the X-ray photons that impinge on the first screen 147 are detected by it while about 24% of the remaining X-ray photons are detected by the second screen 148. It should be noted that these percentages can change, depending on the energy of the X-rays and the thickness of the scintillator screen.

The photomultiplier tubes 150 generate electronic signals in response to the detected rays that are initially converted to light. The light emitted by scintillation on the screens 147, 148 bounces around the triangular enclosures / towers 110, 120 until it is captured with the photomultiplier tubes 150.

The electronic signals produced by the two detector towers 110, 120 are directed to a processor. The processor analyzes the received signals and generates an image in a display medium. The intensity at each point in the image that is displayed corresponds to the relative intensity of the scattered X-rays that are detected while the beam is tracked through the subject. In one embodiment, the X-ray source 160 communicates synchronization signals to the processor. The processor analyzes the detected signals and compares them with the synchronization signals to determine the display image. In one embodiment, the display means is a monitor and is used to display graphic images indicated by the processor. The display means can be any screen or monitor as is commonly known in the art, including a cathode ray tube monitor, an LCD monitor or an LED monitor. In one embodiment, the digitized scatter image displayed by the display means preferably consists of 480 rows per 160 columns with 8 bits per pixel.

In one embodiment of the present invention, and as shown in greater detail in Figure 8, however, a single-axis scanning beam through which a lens is traveling is employed. The movement of the objective's gait provides the second axis of movement. Therefore, at any given time where the subject descended in section 103 or target moves through the fine X-ray beam 102 that moves vertically, the precise location of the beam is known through the motor that controls the trochador wheel (described in more detail later). At each instant, the arrangement of the detector 106 provides the measured response of the backscattered X-rays, the intensity of which is represented in the resulting image. Because the system knows exactly where the fine beam is located at each instant when the backscattered rays are detected, the image can be "joined" together, to form the exhaustive image of the target.

Therefore, in one embodiment, a fixed vertical scanning beam constitutes an axis of motion and the subject that is intended provides the second axis of movement when walking or being carried through the vertical scanning beam. This configuration is convenient since the single-axis beam requires a very small rectangular aperture in the detector panel. In current backscattering detection systems using a dual axis scanning beam, mechanical assembly requires a significant opening between the detectors to allow the scanning beam to exit. An important opening is required since for a dual-axis scanning beam system when the target is stationary (where a rotating trochane wheel provides an axis of motion and the vertical movement of this rotary trocar wheel provides the second axis of motion ), the fine X-ray beam is projected in the horizontal direction. Therefore, to cover an objective the size of a person, the opening must be wider to allow the beam to cover the entire person. In addition, a conventional aperture of large size allows a large portion of the backscattered radiation to escape undetected.

As described above, in one embodiment of the present invention, the second axis of movement is provided by the moving target. Therefore, the beam can be oriented for vertical movement to allow a smaller opening and optical positioning of the detector. Referring again to Figure 1, and as described above, the single-axis scanning system of the present invention incorporates a small rectangular aperture 172 between the detector regions 110 and 120 so that the rays exist emanate therefrom. In addition, the small opening 172 makes it possible to position additional and / or larger detector panels in the direct backscatter path, thereby improving the image quality.

As described above, the thin beam 102 is traced either horizontally or vertically through the subject, by employing a beam changer mechanism by allowing only a minimum exit aperture for the X-ray beam to be projected. In one embodiment, the beam changer mechanism is a trochador wheel having three slits positioned at 120 degrees apart and aligned with two parallel slots of collimator such that each slitter of the trocador will leave one of the slits of collimator parallel while another enters the other parallel slit opposite. This creates two parallel scanning beams that are interleaved in time and that can be processed separately even with a single common detector arrangement, circuits and processing, all using a single source that conically illuminates the two parallel slits.

Figure 5A illustrates a top view of an exemplary bailor wheel 500 that can be used to obtain dual vision (using two parallel, interleaved scanning beams) using a single source. The trocar wheel 500 has three slits, 501a, 501b and 501c, placed at an angular distance of 120 degrees from one another. There are also two parallel collimator slits 502a and 502b. The arrow 503 represents the direction of movement of the trochador wheel, which in this mode is in the direction of the hands of the clock. This arrangement creates two "stepped" parallel scanning beams that, as mentioned above, are interleaved in time and therefore can be processed separately using common detectors, circuits and processing components.

In one embodiment, the disk changer assembly is dynamically controlled by rotation using an electromagnetic motor pulse. Figure 5B illustrates an exemplary disk-changer assembly, with electromagnetic motor and integrated supports. With reference to Figure 5B, the disk changer 501 is coupled to the radiation source 502, which, in one embodiment, comprises an X-ray tube. The electromagnetic motor 503 is integrated with the X-ray tube 502 and the trocador 501. The motor assembly further comprises three compression brackets 504, and one V-slot 505 for transmission belt backing. Figure 5C illustrates the X-ray tube (source) 501 coupled to the disk changer 502, minus the motor assembly.

In one embodiment, the X-ray inspection system further comprises a reference detector that compensates for and monitors each emitted beam and also functions as a radiation monitor to monitor the radiation emitted within the inspection region. The reference detector is, in one embodiment, positioned within the trajectory of the beam before the beam tracing apparatus, such as the beam baffle disk. The reference detector may also be positioned after the beam tracing apparatus, such as the beam baffle disk, at the beginning of the scanned line formed. In such a case, the radiation detector can acceptably block the first 2 degrees of the beam.

Figure 6A illustrates an X-ray source being used in conjunction with a trocar wheel, as described in Figures 5A, 5B, and 5C, in an exemplary threat detection system. The source and the trocar wheel are coupled to a "CAM" tilting mechanism in such a way as to substantially enable equal spacing between the scanning lines along the vertical movement of the X-ray beam. With reference to Figure 6A, the module comprises a CAM 602 tilt mechanism coupled with an assembly of the X-ray source 610 all housed in the frame 620. The tilt mechanism CAM 602 further comprises the CAM guide 604. In addition, it is also housed in the frame 620 an engine to drive the CAM mechanism and the belts used to lift the source. In one embodiment, a handle is attached to the source assembly 610 to enable adjustment and removal of the source assembly of the metal guide frame 604. In different embodiments, all parts of the source assembly are attached safe when using predefined sizes of nuts, bolts and clamps. In addition, the lifting belt 606 is provided to further enable the lifting and counterbalancing of the source.

Figure 6B shows a diagram of the tilting mechanism CAM 602 in an expanded view, further shows the driving wheel 640 supported against the arm of CAM 642 in such a way as to enable the vertical movement of the source.

In another embodiment, a counterweight is used to counterbalance the source and reduce the effort in the lifting motor. In another modality, two lifting belts can be used to counterbalance the source, eliminating the counterbalance and resulting in a much lighter source. In another mode, a gear reducer (15: 1 reduction) and a higher torque motor can be used to eliminate the use of counterbalance, since the source now looks 15 times lighter than the engine. However, the motor, in this case, would have to be 15 times faster to achieve the same radiation pattern.

Again with reference to Figure 6A, the source assembly 610 comprises an X-ray source 612 and a disk wheel changer 614 made of a suitable material such as metal or plastic to guide X-rays 616 generated by the source X-ray in a desired direction. In one embodiment, the source assembly 610 also comprises a high voltage power supply that enables the operation of the source assembly. In one embodiment, the X-ray source 612, together with the beam changer mechanism 614, generates a narrow fine beam of X-rays which are directed towards a subject under inspection through the rotation of the source or transverse beam to create a scanning line. In one embodiment, the disk wheel beam changer mechanism 614 will optionally be coupled with a cooling plate, which dissipates the heat generated by the rotary wheel. Figure 6C illustrates another view of the module illustrated in Figure 6A, further showing a turntable 650 for rotating the corresponding source and power supply.

It should be understood by persons experienced in the art that radiation sources are typically very heavy. In order to accommodate the weight of the X-ray source, a trocar wheel configuration, as above, has to be quite large, and therefore contributes to the overall weight of the system. Therefore, in another embodiment, the inspection system of the present invention is equipped with a rotary roller gauge which is designed to present a helical profile opening shutter for X-ray beam scanners and which is light weight and easy to unfold. In addition, the use of the rotary roller gauge eliminates the need for rotation of the source, rather the beam rotates horizontally from -45 to +45 degrees.

In one embodiment, the rotary roller gauge allows for variability in both speed and spot size of the beam by modifying the physical characteristics or geometry of the beam tracing apparatus. In addition, the rotary roller gauge provides a beam point that moves vertically with constant size and speed to allow equal illumination of the target and create a wider field of view during its operation.

Figure 7A illustrates an exemplary design for a rotary roller bait mode, as used in different embodiments of the present invention. The beam changer 702 is manufactured, in one embodiment, in the form of a hollow cylinder having helical trocar slots 704. The cylindrical shape enables the beam changer 702 to rotate about the Z axis and together with the helical apparatus 704 , they create a rotating roller movement.

Therefore, an X-ray beam scanner employing the rotary roller baler of the present invention effects beam switching by rotating the hollow cylinder 702 machined with at least two helical grooves 704, which enables beam scanning X-rays with constant and variable linear scanning beam speed and scanning beam spot size. The rotary roller gauge enables the constant and variable linear scanning beam speed when manipulating the geometry of the helical openings. In a modality, the speed is varied or kept constant by manipulating the inclination and rotation of the helical openings together with the length of the rotary roller counter. Therefore, it is possible to have a constant speed or to decrease scanning in areas where higher resolution is desired.

The rotary roller gauge also enables the variable and constant beam spot size by manipulating the geometry of the helical openings, thereby varying the resulting beam energy. In one embodiment, it is possible to manipulate the actual width of the aperture to alter the size of the beam point. In one embodiment, the width of the helical aperture varies along with the length of the rotating roller trocar cylinder to compensate for the variable distance of the aperture from the center of the source and allow uniform projection of the beam point along the length of the aperture. scan line Therefore, in one embodiment, the further the source aperture is, the narrower the width of the helical aperture to create a smaller beam spot size. In one embodiment, the closer the source opening is, the broader the width of the helical opening to create a larger beam spot size.

When used in a body scanning system, it is possible to vary the inclination and twist and width of the helical openings in such a way that more scanning beam energy is directed towards areas of the body (hair, feet, etc.) that require greater detail and resolution and less energy is directed towards areas of the body (middle section, etc.) that are more sensitive to radiation.

The helical slits 704 also ensure that the projection of the X-ray beam is not limited by the dual collimation of the two slits. As described in more detail below, dual collimation refers to the concept by which the X-ray beam will pass through two helical slits at any given point in time. The path 730 of the resulting X-ray beam is also shown in Figure 7A and is described in greater detail with respect to Figure 7C below.

In one embodiment of the present invention, a plurality of viewing angles ranging from 60 degrees to 90 degrees can be obtained through the helical slits in the rotary roller gauge. In one embodiment, the scan angle is a function of the distance between the rotary roller changer and both the source and the target. In addition, the general height and diameter of the rotary roller gauge affect the viewing angle. The nearer the rotary roll of the fountain is placed, the smaller the rotary roller baler needs to be and similarly, the further away the turntable rotary roller from the source is placed, the larger would be necessary for the roller baler to be rotary.

Figure 7B illustrates a beam changer mechanism using the rotary roller baler described with respect to Figure 7A. With reference to Figure 7B, the cylindrical rotary roller gauge 752 is placed in front of a radiation source 754, which, in one embodiment, comprises an X-ray tube. In one embodiment, the rotation of the gauge 752 is facilitated by including a suitable motor 758, such as an electromagnetic motor. In another embodiment, as described in greater detail below, magnetic carriers are used to facilitate the rotational movement of the rotary roller baler of the present invention. The rotational speed or revolutions per minute (RPM) of the rotary roller baler system is controlled dynamically to optimize the scanning speed. In one embodiment, the rotary roller baler system is capable of speeds up to 80K RPM.

In one embodiment, the radiation shielding is provided at the radiation source 754 such that only one fan beam of radiation is produced from the source. The beam in a radiation beam emits X-rays and then passes through the rotary roller gauge, which acts as an active shutter. Therefore, there is only a small opening when the rotary roller gauge, and therefore the helical openings are rotating, which provides the flying motion knitting beam.

Figure 7B also shows a disk changer wheel 760 superimposed on the source together with the rotary roller changer. It can be seen from Figure 7B that the wheel of the bait 760 is substantially larger than the rotary roller bait 752.

According to one embodiment of the present invention, at certain distances from the center of the bundle, the helical slit (of the rotary roller gauge) remains wider than others. According to one embodiment, Figure 7C shows a mathematical expression of the beam path 770 using a single source. In order to obtain the dimensions of the helical cuts in the cylinder of the rotating roller, a dimension of this trajectory was removed. More specifically, the slit is narrower at the top 775 because there is a greater distance for the beam to travel. Observe that when an X-ray beam travels through any opening, the beam collimates. The farther the beam travels, the wider the resulting "point" (fan beam) at the end of the beam. By making the slit narrower in the upper part 775, this greater distance and amplitude of the beam is taken into account. In addition, the slit is made wider where the distance to the object is shorter, such as at point 780. Also, persons skilled in the art would appreciate that by controlling the size of the slit one can control the density of the beam that is projects directly through it.

The United States Provisional Patent Application Number 61 / 313,772 entitled "Walk-Through People Screening System," and presented on March 14, 2010, and its applications. corresponding to children are incorporated herein by reference in their entirety.

The system of the present invention is designed in such a way that the distance of the beam changer mechanism from the target is directly correlated with a minimum scanning height. This allows greater distance from the source to the target, thus extending the depth of field with respect to the dose rate in the target. Therefore, for a given depth of images, a lower radiation dose is required with the system of the present invention compared to other systems known in the art.

An exemplary practical application of the inspection system of the present invention is illustrated in Figure 8. With reference to Figure 8, the first scanning side 810 and the second scanning side 820 are used to create an inspection area through which the individual walks by being scanned. The first scanning side 810 comprises two detector panel towers 811 and 812. In one embodiment, the X-ray enclosure 813 is also located proximate the first scanning side 810. The second scanning side 820 is positioned through the gateway. from the first scanning side 810, thereby forming the inspection area or volume 840. The second scanning side 820 comprises two detector panel towers 821 and 822. A second X-ray enclosure is located next to the second scanning side 820 While the subject 830 walks through the system both the first scanning side 810 and the second scanning side 820 scan the subject to obtain an image of both a left front view and a right rear view of the person. In one embodiment, the first scanning side 810 and the second scanning side 820 scan the subject sequentially, with a minimum time delay between scans. Therefore, subject 830 does not need to flip or stop for scanning; a complete image is produced simply while the person walks through the inspection area 840. In one embodiment, a person being scanned is carried or moved, such as by means of a moving walkway, through the detection area. The generated image can be reviewed at the operator station 850. Since the scanning sides comprising a source and detector array are used to generate images, the image produced by each scanning side can also be viewed individually. Therefore, with reference again to Figure 8, the operator screen 860 also separately presents front and rear views 852 and 854, respectively, in addition to the overall image 856. Also, in this type of walk-through arrangement, Several people can be inspected quickly simply by asking them to walk through the inspection area in a row. In the exemplary application, operator screen 860 also displays front and back row images, 852 and 854, of three people.

It should be appreciated that the inspection system is capable of generating images of metal objects as well as non-metal objects (including explosives and non-metal weapons) in a person (including with or under clothing) without removing the clothing and is able to process generated images to show only the outline of a body and highlight threatening or illegal objects, including both organic and inorganic materials, and while hiding the private characteristics of the body, thus creating a private image. The inspection system can be configured in such a way that only the private image will be available to the operator. Alternatively, the system can be configurable in such a way that the private image is the default image but the coarse image, generated before processing to show only a contour of the body and the threat or illegal objects, is still available to the operator.

Additionally, system a) comprises an internal safety monitoring circuit to continuously monitor the safety of the system and radiation levels during each scan, b) provides a dose of ionization radiation no greater than 5 microrems per scan for any person under inspection, c) scan one side of the person in 8 seconds or less, d) it must be no longer than 1.25 m long (the length dimension of the person facing the scan), e) it must be no wider at 1.0 m, f) must have height no greater than 2.05 m, g) must have an optional wall to assist in the privacy of the subject being inspected and prevent background interference, which improves the detection capabilities of the system by making the inorganic objects on the lateral edge of the body more visible in the image and allow full coverage of the body in 2 scans opposite to the 4 scans when the wall is not used, h) must have a monitor of Optional communications to facilitate communication between a remote inspector and a local operator and to communicate a real body image outline instead of a stickman or simplified man image, this is "stick man". { stick man), with search locations highlighted when the image is "calibrated" to adjust for varying body heights of people in relation to the body height of the stick man, i) it should be able to scan a 1.83 cm person ( 6 feet) stop 25.4 cm (10 inches) apart, measured from the detector wall to the nose of the person, j) must be able to communicate with a work station deployed away from the scanning system, k) should be possible start a scan from the remote workstation, 1) you can configure it for a predefined number of scans per person that you must complete before increasing the next person, m) you must allow extra scans to be taken, as an option available for a operator, before incrementing the next person, n) must be configurable to force an operator to pass or clean each scan independently, even if multiple scans are required the same person, or) must communicate the scan results (pass or fail) to a remote operator through a visual light indication, which can be viewed remotely by the remote operator, in the local system, that is, a red light for "fails" and a green light for "passes", p) must be able to report which operator registered in the system during the time period and how many people were scanned by the operator during that period, how many people in total were scanned during each hour of the day, and the number of scans and number of people scanned at any predefined time period (such as time, day, or month), q) should have the option of a training simulator with a library of images of at least 100 training images. U.S. Patent No. 7,110,493 is incorporated herein by reference.

The image processing software of the detection system of the present invention makes use of appropriate algorithms to reconstruct images such as combining separate front and back images to create a complete image, as well as for image analysis to determine threats. In one mode, a segmentation algorithm is used to distinguish threat objects. An example of using the segmentation algorithm is illustrated in Figures 9A to 9C. With reference to Figure 9A, image 901 shows a person free of threats transported in the body (benign subject). In Figure 9B, the image 902 shows a person carrying a backpack 903. In order to determine if the backpack represents a threat, the software uses the segmentation algorithm to segment the backpack 903 of image 902, and generate an image separated 904 as shown in Figure 9C. The size of the object and the pixel intensity of the segmented object are then used to identify threats.

The segmentation algorithm is also used to distinguish dark objects on a white background. This feature helps to accurately identify threats that comprise absorbent materials, such as metal knives and guns, and ceramic knives. An example of the use of this feature of the segmentation algorithm is illustrated in Figures 10A and 10B. With reference to Figure 10A three potential threat objects 1001, 1002 and 1003 are detected in the individual 1004 that is being scanned. In Figure 10B, two threat objects 1005, 1006 are detected in the individual 1007 that is being scanned. In both Figures 10A and 10B, the same algorithm is used to generate images, with the same parameter settings. From these images, it would be apparent to a person skilled in the art that the image analysis algorithm that is used by the detection system of the present invention is significantly insensitive to the background level. This is because the background is calculated from the same original image, and any potential threat is highlighted. As would be apparent to one skilled in the art, as shown in Figures 10A and 10B, the individual's body only reaches a partial area of the image. The balance of the image is considered as a scattered X-ray signal of the background. Computational methods as simple as average or localized smoothing (average over localized areas) provide accurate measurement of the background signal level.

In addition, the image analysis algorithm of the present invention also facilitates fast inspection, since it typically takes less than one second to generate an image.

US Patent Application Number 12 / 887,510, entitled "Security System for Screening People", and United States Patent Number 7,826,589, of the same title, both assigned to the Applicant of the present invention are hereby incorporated by reference in their entirety.

U.S. Patent Application Number 12 / 849,987, entitled "Personnel Screening System with Enhanced Privacy" and United States Patent Number 7,796,733 of the same title, both assigned to the Applicant of the present invention are hereby incorporated by reference in their entirety.

As mentioned above, with respect to Figure 1, the design of the present invention allows for more detector panels to exist in the direct backscatter path, thus contributing to the image quality. The image quality is further increased in another mode, by using an approach that increases the area of the detection field and the number of detectors that can be used. This new approach is described with reference to Figures 11 and 12. Figure 11 illustrates a side view showing vertical scanning with a single source 1101. In this configuration, the height 1102 of a subject 1103 that can be scanned using the unique Source 1101 is limited by the 1104 width of view or the illumination extension of the source.

To overcome this limitation, the present invention, in one embodiment, employs a new configuration that is illustrated in Figure 12, which shows a view of the top of the exemplary scanning arrangement. With reference to Figure 12, the assembly of the single-axis scanning source 1201 is pivoted from point 1202a to 1202b, with a center of rotation 1203 on the front panel of the system. As can be seen from Figure 12, 1204a is the viewing width available for the subject 1206, when the source 1201 is fixed, while 1204b is the available viewing width when the source is pivoting. Therefore, the width of vision for a given source expands when it is pivoted. In this case, a greater number of detectors 1205 can be added to the system, thus providing an increased detection area. In addition, a fixed rectangular aperture is provided in the front panel, which also serves as an aperture that keeps the focal point very small in at least one axis. In addition, with an optionally pivoting source as shown in Figure 12, the same system can be used to perform lens scans when the person is in motion (and the source is not pivoting) or when the person is stationary (and the source is pivoting). With a stationary lens, the image quality is nominally better than when the lens is in motion because the distortions are caused by differential velocity in the part of the subject in motion (eg, legs and arms). Therefore, under certain operational situations, the same system could carry out a more detailed scan (with the stationary objective) if an anomalous object is found in the first scan (when the target is in motion). The choice of system depends on the scanning requirements and is a trade-off between threat detection and high performance.

As described above, in one embodiment, the detection system of the present invention is implemented as a walk-through detection system. The new design of the walk-through system enables the use of low-level radiation doses for the detection of weapons and hazardous materials, regardless of whether they consist of metal, high Z or low Z materials. The radiation dose is in a range of less than 20 microrems, preferably less than 10 microrems, more preferably less than 5 microrems and more preferably less than 1 microremre. This portal configuration can accommodate a high performance of people compared to conventional systems since each person being inspected simply walks through the portal. In addition, the person being inspected does not need to stop and turn his body as directed by an operator of the scanner system. In addition, by using such portal configuration through which the target walks, with its relatively confined area, it is easier to combine with other walking devices, including metal detectors, drug and explosives sniffer dogs, and video cameras. .

In addition to being used for the inspection of passengers at airports and railway stations, in open and crowded places such as stadiums and shopping centers, the applications of the system of the present invention can be extended to the inspection of contents of vehicles and containers at points of transit such as ports, border crossings and common checkpoints, etc. In one embodiment, the detection system is implemented as a "pass through" system, through which a load vehicle can be handled by being scanned, thus providing a second axis of movement. The detection system of the present invention can also be used for medical purposes.

In cases where there is a short distance between the target and the source, a large scan angle is required for nearby scans. This requirement of a large scan angle competes with the size of the wheel of the trocador and the spatial resolution. In order to achieve a balance between conflicting requirements, the system of the present invention, in one embodiment, employs a dual wheel approach using a flight aperture for range selection. This is illustrated in a top view of the scanning system in Figure 13. With reference to Figure 13, the embodiment illustrated uses two tracker wheels 1301 and 1302. The tracker wheels 1301 and 1302 have slits 1303 and 1304. , respectively, which provide a fixed aperture for the radiation beam. A flight aperture 1305 is also provided near the source 1306 which is used to select vision or scanning range just before the subject enters the scanning area. In one mode, range selection is aided by the use of the sensor and / or camera. The range selection feature of the present invention allows several optical geometries to be used for different target ranges.

In one embodiment, each trocar wheel used in the dual wheel arrangement described above has interior and exterior slits with different slit sizes, scanning and filtering angles. Figure 14 illustrates an exemplary bail wheel 1400 that can be used in the dual wheel system. With reference to Figure 14, the wheel 1400 has inner slits 1401 and outer slits 1402 that can be used to obtain a fixed opening with two views and two different scanning angles.

Figure 15 illustrates another top view of the vertical scanning system with the flight aperture 1502 positioned near the source 1501. The system has a near-view driver 1503 with the slits 1505 and a far-sight driver 1504, the slits 1506 The outer slots of the nearby 1503 viewer are used for the closest view, the largest scanning angle, the highest filtration and their inner slits are used for the fairly close view with medium scan angle and filtration. The outer slots of the 1504 far-view bater are used for moderately far view, small scanning angle, low filtration and their inner slits are used for the furthest range with the smallest filtering scanning angle. The use of two wheels of the trocador for selection of angle of scan and of rank also offers the opportunity to adjust the levels of dose based on the distances of the objective.

In another modality, the system is implemented as a system of walking through backscattering of four views of two sides, of double source, which also works on the principle of employing a beam of scanning of a single axis with the movement of the object / subject through the beam providing the second axis. Figure 16 illustrates an exemplary arrangement for the dual view system, quadratic range. With reference to Figure 16, two sources 1601 and 1602 are used. Two trocators are used with each source for near and far views in an arrangement similar to that discussed above with reference to Figures 13 and 15. In the arrangement of Figure 16 however, the nearby 1603 is shared between two sources. Two distant trocars 1604 and 1605 are used for sources 1601 and 1602 respectively. In one embodiment, all of the tracker wheels 1603, 1604 and 1605 have three slits each. In addition, the trocar wheels 1604 and 1605 are synchronized in geometry as well as movement. A "Vertical Scanning Aperture" or VSA (Vertical Sean Aperture) 1606 is provided in the scanning system which is connected between the detector panels thus offering better spatial resolution on an axis. In one embodiment, the VSA 1606 comprises multiple slits and helps maintain high resolution on the X axis.

In this embodiment, a single VSA 1606 is used for beams 1607 and 1608 emanating from both sources 1601 and 1602, respectively. The dual bridge arrangement described above provides near views or ranges at larger angles. This keeps the far targets closer to the center of the detector and therefore provides better image generation for range or quadratic views.

In one embodiment, the detection system of the present invention uses the concept of "vector images" (vector imaging) to obtain additional information in images. In current imaging methods, the signals from the detectors are all summed electrically. However, in the vector image method of the present invention, the signals generated in multiple detector panels are separated. This allows additional information to be obtained from "vector" that is otherwise masked. This concept is illustrated in Figures 17A to 17C.

With reference to Figures 17A to 17C, a series of images illustrates the response of two detectors to a beam of radiation passing through an object.

In general, when the X-ray beam approaches a contour or edge of a material, the dispersion will be blocked in the direction of the thickest object and a reduced signal will occur in the director opposite the edge. As the point passes through the thicker material, more dispersion comes out through the recent edge towards the thinner side and the corresponding detector receives more signal. This is the method for determining contours in current image generation systems, with dark regions followed by clear regions in the image. Having separate signals, however, would offer additional information as the point moves across the edge.

Now with reference to Figure 17, initially, signal 1705 received in DI 1701a begins to decrease while point 1703a approaches the edge of object 1704a. At this time, signal 1706 received at D2 1702a remains normal. In the central part of Figure 17, while point 1703b moves on the edge of object 1704b, signal 1705 corresponding to detector DI 1701b begins to increase back to "normal" while signal 1706 for D2 1702b increases above normal until point 1703b has moved some distance past the edge of object 1704b and returns to normal.

During the transition as shown in the right part of Figure 17, the 2006 signal of the detector D2 1702c grows while the signal 1705 of the DI 1701c is still returning from a reduced state.

At this time, a loss of information occurs if a combined signal (DI + D2) is used, as is apparent from curve 1707 which represents the combined signal. This is because when the signals for DI 1705 and D2 1706 are the same at points A 1711 and B 1712, the combined signal DI + D2 1707 also follows the same path. However, the difference signal (DI-D2), as represented by curve 1708, touches a value close to zero at point A 1711 and a positive value (or + vector) at point B 1712. Similarly, the difference signal for an opposite edge contour would create a negative vector value. This additional information obtained from the difference signal curve 1708 can be used to improve the contours and edges in the images shown.

The above examples are only illustrative of the many applications of the system of the present invention. Although only a few embodiments of the present invention have been described herein, it should be understood that the present invention can be modeled in many other specific forms without departing from the spirit or scope of the invention. Therefore, the present examples and modalities they should be considered as illustrative and not restrictive.

Claims (30)

NOVELTY OF THE INVENTION Having described the present invention as above, it is considered as a novelty and, therefore, the content of the following is claimed as property: CLAIMS

1. An inspection system to detect objects that are transported by a person, where said person moves along a plane defined by a Z axis and a Y axis, the inspection system comprises: a first detection system configured to detect radiation scattered by said person while the person is moving along the Y axis of the plane, wherein said first detection system comprises a first flat surface positioned opposite the plane, and configured to generate electronic signals sensitive to the radiation detected; a second detection system configured to detect radiation scattered by said person while the person moves along the Y axis of the plane, wherein said second detection system comprises a second flat surface positioned opposite the plane, and configured to generate electronic signals sensitive to the radiation detected; an X-ray source positioned between said first detection system and said second detection system, wherein said first X-ray source is configured to generate a beam point pattern along the Z-axis of the plane and wherein said source of X-ray does not generate beams that move along the Y axis of the plane; Y a processing system for analyzing the electronic signals generated by the first detection system and the second detection system and for generating an image on a screen.

2. The inspection system according to claim 1, characterized in that the X-ray source is coupled with a beam tracker and wherein said beam tracker operates to produce a thin beam of X-ray scanning along the Z axis.

3. The inspection system according to claim 2, characterized in that the beam tracker does not produce a thin beam of X-ray scanning along the Y axis.

4. The inspection system according to claim 2, characterized in that said beam tracker comprises a trocar wheel having three slits and wherein each slit is positioned 120 degrees apart from an adjacent slit. The

5. The inspection system according to claim 4, characterized in that said slits are aligned with at least two parallel collimator slits and wherein the X rays emitted from the X-ray source conically illuminate the slits of the collimator to generate at least two beams of parallel scanning interspersed in time.

6. The inspection system according to claim 2, characterized in that the beam changer comprises a hollow cylinder having at least one helical opening.

7. The inspection system according to claim 6, characterized in that the thin scanning beam has a linear scanning speed and wherein said linear scanning speed varies or remains constant when modifying the inclination and rotation of at least one of said openings helical

8. The inspection system according to claim 6, characterized in that the fine scanning beam has a point size and wherein said point size varies or remains constant when modifying an opening width of at least one of said helical apertures.

9. The inspection system according to claim 1, characterized in that the first detection system is contained within a first enclosure, wherein said first enclosure has a first width extending from one end of said first enclosure to an opposite end of the enclosure. said first enclosure and wherein the flat surface extends along the entire first width.

10. The inspection system according to claim 9, characterized in that the second detection system is contained within a second enclosure, wherein said second enclosure has a first width extending from one end of said second enclosure to an opposite end of the enclosure. said second enclosure and wherein the flat surface extends along the entire first width.

11. The inspection system according to claim 10, characterized in that the first enclosure is physically separate from, and independent of, said second enclosure.

12. The inspection system according to claim 10, characterized in that the X-ray source is contained within a third enclosure and wherein the third enclosure is physically separated from, and independent of, the first and second enclosures.

13. The inspection system according to claim 12, characterized in that each of the first, second, and third enclosures weigh less than 40 kg (88 pounds).

14. The inspection system according to claim 12, characterized in that the third enclosure can be detachably connected to the first enclosure and the second enclosure.

15. The inspection system according to claim 12, characterized in that each of the first, second, and third enclosures can be detachably connected to a frame.

16. The inspection system according to claim 1, characterized in that the beam changer comprises a disk changer that is configured to be rotated by a motor.

17. The inspection system according to claim 16, characterized in that a speed of the tracker wheel is controlled dynamically by a controller to optimize a scan speed of the X-ray beam.

18. The inspection system according to claim 10, characterized in that the first enclosure comprises: a first side defined by a flat surface having an exterior surface facing the person and an interior surface, wherein the first side is configured to receive radiation scattered by the person; a second side in an acute angular relationship with said first side, wherein said second side is defined by a flat surface having an inner surface adapted to receive radiation passing through the first side and wherein said second side is configured to receive only radiation after it passes through said first side; a first substrate positioned on the inner surface of the first side, wherein the first substrate further comprises an active area for receiving and converting said radiation into light; a second substrate positioned on the inner surface of the second side, wherein the second substrate further comprises an active area for receiving and converting said radiation into light; Y at least one photodetector having a light-sensitive area and an area not sensitive to light, wherein the light-sensitive area is positioned to receive the light emitted from the first substrate and the second substrate.

19. The inspection system according to claim 18, characterized in that said radiation comprises X-ray photons and wherein said first substrate detects 30-60% of the X-ray photons incident on said first side.

20. The inspection system according to claim 19, characterized in that said second substrate detects 10-30% of the X-ray photons incident on said first side.

21. The inspection system according to claim 1, further comprises a conveyor to enable a person standing or sitting to move along the plane.

22. The inspection system according to claim 1, characterized in that the generated image comprises 480 rows, 160 columns, and 8 bits per pixel.

23. The inspection system according to claim 1, characterized in that the X-ray source generates a beam point pattern along the Z axis of the plane when pivoting from a first point to a second point and wherein said pivot is centered around a predefined point of rotation.

24. The inspection system according to claim 1, characterized in that the X-ray source and a beam changer are coupled to a surface configured to tilt vertically relative to a guide member and in response to a motor.

25. The inspection system according to claim 1, characterized in that the X-ray source is coupled to a vertical lifting mechanism wherein said lifting mechanism is coupled to a weight configured to counterbalance the X-ray source.

26. The inspection system according to claim 1, characterized in that the X-ray source is coupled to a vertical lifting mechanism wherein said lifting mechanism is coupled to at least one lifting strap.

27. The inspection system according to claim 1, characterized in that the X-ray source is coupled to a vertical lifting mechanism wherein said lifting mechanism is coupled to a gear reducer and motor and is not coupled to a counterbalance weight.

28. A method for detecting hidden threat objects in a person's body by using an inspection system comprising at least one radiation source to produce a thin beam of X-ray scanning, wherein said fine scanning beam has a trajectory, and a detector arrangement comprising at least one first detector enclosure having a first surface and a second detector enclosure having a second surface, the method comprising the steps of: a) causing the person to move past at least one source of radiation in a plane perpendicular to the beam path of the scanning thin beam and parallel to said first surface and second surface; b) generating an X-ray beam within a radiation source enclosure, wherein the radiation source comprises an X-ray source coupled with a beam tracker and wherein the fine scanning beam is collimated by at least one slit in the enclosure of the radiation source to generate a vertical beam spot pattern and not a horizontal beam spot pattern; c) detecting radiation dispersed by the person in at least one of the first detector enclosure or second detector enclosure; Y d) process the detected radiation to generate a two-dimensional image, where said image shows any hidden explosive material being transported by the person.

29. The method according to claim 28, characterized in that the first beam baler comprises a baler assembly having a hollow cylinder with helical slits extending along a length of the cylinder, a cylinder of carbon fiber covering the cylinder. hollow cylinder, and a cylinder of epoxy polyethylene that covers the cylinder of carbon fiber.

30. The method according to claim 29, characterized in that the trocar assembly is rotated by a magnetic support assembly comprising a magnetic rotor and a magnetic support stator and wherein the magnetic support assembly provides magnetic levitation for the assembly of trocador at least during the on and off states of the beam changer.