Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The following patent application is based
on and claims the benefit of U.S. Provisional Patent
Application Serial No. 60/062,684 filed October 22,
1997.
FIELD OF TH.F INVENTION
The present invention relates generally to
walk-though scanning systems such as found in airport
check-in, or other high-risk security areas, and more
particularly, to a novel scanning system implementing
a combination of different detection technologies,
each optimized for the detection of certain types of
concealed or suspicious objects or features.
Portals for screening people carrying
metallic objects or explosives exist in several
forms. They, in general, are classified as walk-in
systems which require that the person stand still at
a designated spot for at least a few seconds while
being scanned; and, walk-through systems, where the
person walks through a portal, e.g., metal detection
portals as seen in airports. The walk-in systems are
inconvenient in that the person has to stand still
at a designated spot which slows down the throughput
in the system. The person additionally becomes aware
of the security scan, which may not be desirable in
certain circumstances. Some of the walk-in systems
available in the market are: SecurScan~ portal
system by Thermedics Inc., MA, USA, which is used for
the collection of explosive vapors, and, the Secure
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1000~ by Nicolet Imaging Systems, USA which is used
for detecting concealed objects on persons using X-
rays.
Walk-through portals exist for different
types of scanning, the most popular being the metal
detection portals as seen in airports. Issued U.S.
Patent No. 4,987,767 designed and developed by CPAD
Technologies Inc. (Nepean, Canada) describes a walk-
through portal for collecting and analyzing explosive
vapors from concealed objects on people. Ion Track
Instruments Inc. (Mass., USA) has developed the ITI
85 Scanner utilizing an air curtain principle for
transporting explosives vapors onto a collector for
analysis. Detection of concealed objects is done
using X-ray scanning in the scanner developed by
Nicolet Imaging Systems, USA. The SecurScan~ portal
system made by Thermedics Inc. has been modified to a
walk-through system with brushes for removing traces
of explosives from people's clothing which are then
processed and analyzed using a gas chromatographic
column and a chemiluminescent detector.
Each of the above described systems rely on
a single method to detect concealed objects like
metal or plastic guns, explosives or other suspicious
items. However, it would be much more desirable to
provide a walk-through portal integrating more than
one of the above technologies in order to create a
synergistic detection system.
SUMMARY OF THE INVE1,~'ION
It is an object of the present invention to
provide a novel walk-though screening and detection
system employing an integrated multi-dimensional
detection and analysis system.
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It is another object of the present
invention to provide a novel walk-though screening and
detection system employing an integrated multi-
dimensional detection and analysis system including
one or more of a metal detector, a vapor analyzer, a
dielectric strength scanner, a set of set of active
and/or passive millimeter wave cameras, and, an X-ray
scanner, or a combination thereof.
According to the principles of the invention
there is provided an integrated walk-though system for
detecting concealed or suspicious objects comprising:
a portal in which a person may walk through without
interruption; a device responsive to a person's entry
into the portal for generating a trigger signal to
start a detection process; one or more of a dielectric
scanner device, an x-ray scanner device, a metal
detector device, a millimeter wave camera device, and
vapor collection and analysis device, or a combination
thereof, for performing respective detection processes
in response to receipt of the trigger signal, each
dielectric scanner device, x-ray scanner device, metal
detector device, millimeter wave camera device, and
vapor collection and analysis device generating
corresponding output signals; and, a computing device
for receiving the output signals from each dielectric
scanner device, an x-ray scanner device, a metal
detector device, a millimeter wave camera device, and
vapor collection and analysis device and generating a
signal indicating detection of a target object carried
by the person.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the
invention will become more readily apparent from a
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consideration of the following detailed description
set forth with reference to the accompanying drawing,
which specifies a preferred embodiment of the
invention, in which:
Figure 1 illustrates the integrated walk-
through personnel scanner system of the invention .
DETAILED DESORIPTION OF THE INVENTION
Figure 1 is schematic diagram depicting the
main components of the integrated walkthrough
personnel scanner system 10 of the invention. As
shown in Figure 1, the system consists of a walk-
through portal 12. Preferably, the portal may be
disguised as part of an archway or corridor when it is
necessary to conceal the scanning process. As a
person 8 walks into the portal 12 a proximity sensor
25, for example, one consisting of an infra-red
transmitter 15a and detector 15b, is triggered which
generates a signal to start the detection and analysis
processes of the various detectors in the integrated
walk-through scanner system 10.
Preferably, there are at least two different
kinds of detectors providing in the, integrated walk-
through system. However, in the embodiment as shown
in Figure 1, there are five different types of
detection systems including: a metal detector 20 for
generating a signal 21 in proportion to the amount of
metal carried by the person 8 and generates an alarm
when the signal exceeds a preset threshold; a vapor
analyzer 30 for sampling the circulating air in the
portal 12 for explosive vapor and particulate which
are carried by the air stream from any concealed
explosives, and generates a signal 31 if any
previously calibrated explosives are present in the
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sample and an alarm signal if the magnitude of the
signal exceeds a preset threshold; a Dielectric
Strength scanner 40 which detects abnormal changes in
the dielectric constant of an object it scans and
accordingly generates a signal 41 representing this
change, in addition to generating an alarm if the
changes are significant enough as determined by a
previously set signal strength; a set of active or
passive millimeter wave cameras 50a,..,50d which scan
the person 8 as he/she walks through the portal 12 and
generates respective images 51a,..,51d of the person
from all angles, which may then be analyzed using
pattern recognition techniques to yield an alarm if
any suspicious pattern is discovered; and, an X-ray
scanner 60 which uses low level X-ray radiation to
scan the person for any suspicious concealed objects
as he/she walks through the portal and creates a set
of images 61 which are then analyzed using pattern
recognition techniques to yield an alarm if any
suspicious pattern is discovered.
The analysis of mufti-state output signals
21, 31, 41, 51a,..,51d, and 61 and the decision to
generate an overall alarm is carried out by computer
software executing on computer system 80 with or
without expert human assistance. For instance, the
different outputs are processed to form a matrix
comprising all possible combinations from which a
final alarm determination may be made. Preferably, a
neural network or AI device implementing fuzzy logic
may be employed for processing the mufti-state signals
and generating an alarm signal 85. It should be
understood that the level of security alert and the
level of tolerance of false alarm rates determines the
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type of analysis performed by the software and the
alarm 85 to be generated.
The data results from the different
detectors are processed in such a way as to readily
arrive at conclusions about the people and the objects
they carry as they walk through the portal.
The foregoing merely illustrates the
principles of the present invention. Those skilled in
the art will be able to devise various modifications,
which although not explicitly described or shown
herein, embody the principles of the invention and are
thus within its spirit and scope.