U.S. patent application number 09/746559 was filed with the patent office on 2002-06-13 for apparatus for illuminating objects.
Invention is credited to Haunschild, Norbert, Springer, Klaus.
Application Number | 20020071520 09/746559 |
Document ID | / |
Family ID | 7667056 |
Filed Date | 2002-06-13 |
United States Patent
Application |
20020071520 |
Kind Code |
A1 |
Springer, Klaus ; et
al. |
June 13, 2002 |
APPARATUS FOR ILLUMINATING OBJECTS
Abstract
In known apparatus (1) there are two radiation sources (10, 20)
in a transport path of a transport device (3), below to the right
and left, as well as a third radiation source (30) arranged
horizontal to the transport path (3), with the two radiation
sources (10, 20) lying close together, one behind the other. Three
detector apparatus (11, 14, 31) are arranged opposite these
radiation sources (10, 20, 30). Thus, a so called multi-view from
three beam directions is created, with beam paths (FX1.1, FX2.2,
FX3) extending perpendicular to a transport direction. Contrary
thereto, in the solution described herein, various radiation beam
paths (FX1.1, FX1.2, FX2.1, FX2.2, FX3) cross so that not every
beam radiation path extends perpendicular to the transport
direction. This has the advantage that the apparatus can be
structured in a space saving manner. In a particular embodiment,
using three radiation sources (10, 20, 30) and five detector
apparatus (11, 12, 21, 22, 31) in a single apparatus, an object (4)
to be transilluminated is transilluminated from five different beam
directions during its transport through a transillumination space
(5) and a quasi 3-D (three-dimensional) model (6) of the object (4)
is thereby, simultaneously created. In this regard, two of the
detector apparatus (12, 21) are arrange angularly displaced from
one another, within one another, to be directed toward
corresponding rays (FX1.2, FX2.1) of the beam radiation sources
(10, 20). With the help of signals obtained therefrom, in addition
to the absorption rate, also the thickness or volume, and therefrom
the density, of the items (4.1) in the object (4) can be
determined. From the absorption rate and the density, the type of
material found in the object (4) and the transilluminated items
(4.1) can be exactly determined.
Inventors: |
Springer, Klaus;
(Selters-Eisenbach, DE) ; Haunschild, Norbert;
(Aarbergen, DE) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
7667056 |
Appl. No.: |
09/746559 |
Filed: |
March 28, 2001 |
Current U.S.
Class: |
378/57 ;
378/51 |
Current CPC
Class: |
G01N 23/083 20130101;
G01V 5/0016 20130101; G01V 5/005 20130101 |
Class at
Publication: |
378/57 ;
378/51 |
International
Class: |
G01N 023/20 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 13, 2000 |
DE |
100 62 214.3 |
Claims
1. Apparatus (1) for transilluminating objects (4) which, with the
help of a transport device (3) are moved through an
transillumination space (5) whereby there are at least two
radiation sources (10, 20, 30) and at least three detector
apparatus (11, 12, 21, 22, 31) mounted about the transport device
(3), characterized in that: at least two ionized beams (FX1.1, FX
1.2, FX2.1, FX2.2, FX3) from different radiation sources (10, 20,
30) cross one another, with at least two detector apparatus (11,
12, 21, 22, 31) also crossing one another along these ionized beams
(FX1.1, FX 1.2, FX2.1, FX2.2, FX3).
2. Apparatus as in claim 1, characterized in that: at least more
than one beam is created by a mask from one of the radiation
sources (10, 20) for creating at least two of the ionized beams
(FX1.1, FX 1.2, FX2.1, FX2.2, FX3).
3. Apparatus as in claims 1 or 2 characterized in that: two
radiation sources (10, 30) cooperate with three detector apparatus
(11, 12, 31), with one of the radiation sources being mounted such
that its beam (FX3) is not directed perpendicular to the transport
device (30), rather it is directed opposite to a beam (FX1.1,
FX1.2) at an angle to a transport plane of the transport device
(3).
4. Apparatus as in claim 1 or claim 2 characterized in that: three
radiation sources (10, 20, 30) cooperate with five detector
apparatus (11, 12, 21, 22, 31), with four of the detector apparatus
(11, 12, 21, 22) being directed toward four beams (FX1.1, FX 1.2,
FX2.1, FX2.2) generated from two of the radiation sources whereby:
two of these detectors apparatus (12, 21) cross within one another
so that they are directed toward one of the two beams (FX1.2,
FX2.1) of the two radiation sources (10, 20) whereby the paths of
these beams (FX1.2, FX2.1) cross.
5. Apparatus as in one of claims 1 through 4 characterized in that:
for mask-defining at least two of the ionized rays (FX1.1, FX 1.2,
FX2.1, FX2.2) at a radiation source (10, 20), a double collimator
or two individual collimators (13, 14, 23, 24) is arranged in front
of each radiation source (10, 20) which are directed toward a
common focus point of the at least two ionized beams, (FX1.1, FX
1.2, FX2.1, FX2.2).
6. Apparatus according to claim 5, characterized in that: the
angularly-displaced directed collimators (13, 14, 23, 24) are
structured as slit collimators which are angularly directed to one
another, respectively in an angular range of 30.degree. to
90.degree..
7. Apparatus according to any one of claims 1 through 6
characterized in that: one of the two collimators (13, 14, 23, 24)
is directed almost parallel to the transport path of the transport
device.
8. Apparatus according to claim 4 characterized in that: a
collimator (32) corresponding to a third radiation source (30)
extends perpendicular to the transport path (3).
9. Apparatus according to claim 8, characterized in that: the
collimator (32) is a slit collimator.
10. Apparatus as in anyone of claims 1 to 9, characterized in that:
the two front radiation sources (10, 20) are arranged below the
transport device (3), to the right and the left, whereby they are
mounted to be offset from one another, one behind the other in the
transport direction, and the third radiation source (30) is
arranged above the transport device (3) in a rear portion of the
transillumination space.
11. Apparatus as in any one the above claims 1 through 10,
characterized in that the detector apparatus (11, 12, 21, 22, 31)
are structured as scintillation detectors which are packaged as
detector lines.
12. Apparatus as in claim 10 characterized in that: the detector
lines (11, 12, 21, 22, 31) are structured to be L-shaped.
Description
[0001] This invention concerns an apparatus for transilluminating
objects as set forth in the preamble of patent claim 1.
[0002] An apparatus for recognizing particularly explosive or other
sought materials in luggage is described in European Patent
document EP 0 485 872 A2.
[0003] In this regard, the luggage is transilluminated from a
plurality of directions with two or three X-ray sources in order to
create therefrom substantially a three-dimensional density
reconstruction of the luggage. The X-ray sources are thereby
positionally offset from one another at the two upper corners of a
cross-sectionally rectangular transport tunnel, through which
luggage pieces are moved. In this regard, two X-ray sources are
arranged closely near to and in front of the other. An L-shaped
detector line is arranged opposite each of the X-ray sources.
Through this apparatus a so-called multi-view is created from the
three beam directions, with all beam planes extending perpendicular
to the transport direction.
[0004] International Patent Publication WO 9712229 describes a
process and an apparatus for detecting smuggled goods, for example,
explosive materials, drugs or money. In this case, a tomograph is
used, with whose help a luggage piece indicated to be a smuggled
good is viewed from various directions. In one embodiment, an X-ray
generator is included in the tomograph. This X-ray generator is
thereby attached to a C-arm. A detector device is also mounted on a
C-arm, opposite the X-ray generator. The C-arm, and thereby the
X-ray generator with the detector device, is moved in continuous
planes for taking various pictures. From the determined absorption
rate of the items in a luggage piece, an effective atom number
Z.sub.eff is determined. Simultaneously, the mass and density of
the detected item are determined by an algorithm.
[0005] An apparatus of the generic type of this invention is
described in U.S. Pat. No. 6,088,423 A, which has at least three
X-ray sources and three detector apparatus which, with the help of
three different ray beam directions, creates a three dimensional
image. In this regard, the radiation beam paths lie perpendicular
to a transport direction. This uses a large amount of space and
means that the apparatus will be large.
[0006] German Patent Publication DE198 23 448 A1 describes an
apparatus to examine physical items using X-ray radiation in which
a mask masks-through an appropriate portion of radiation so that a
beam cone is created which is directed toward a linear shaped
receiver arranged perpendicular to an object, and which creates
time-displaced scan signals from different angular directions.
[0007] It is an object of this invention to provide an apparatus of
the generic type described above which uses very little space.
[0008] This object is achieved by the limitations of patent claim
1.
[0009] According to principles of this invention, in order to
decrease space requirements, at least two ionized radiation beams
from different radiation sources are crossed with at least one of
these radiation beams no longer being perpendicular to a transport
direction or the object, and thereby at least two detector
apparatus which at least partly cross one another are directed
toward these beams. In this manner, with the help of two beam
sources and three detector apparatus, a spatial image of an object
being transported can be created by the beams coming from different
beam angles toward the object.
[0010] Beneficial enhancements are set forth in the dependent
claims.
[0011] In a preferred variant, with the help of three radiation
sources and five detector apparatus, an object to be
transilluminated is transilluminated from at least five different
directions during its transportation in the apparatus and a quasi
3-D (three dimensional) model of the object is simultaneously
created. In this regard, preferably, two of the five detector
apparatus are crossed within one another.
[0012] It is beneficial in one arrangement to have a front
radiation source to the right and a following downstream radiation
source to be left and below the transport apparatus. These are
offset from one another and mounted along the transport path one
behind the other. A third radiation source, contrary to this, is
mounted above the transport apparatus. It is also, however,
understood that the front radiation source can be arranged above
the transport device and the two rear radiation sources can be
mounted below the transport device.
[0013] Preferably, the detector apparatus are structured as
L-shaped detector lines, which are formed of a plurality of
detector pairs arranged one behind the other.
[0014] Preferably, the apparatus will be used in a multi-view
system for automatically determining materials with X-ray beams,
whereby, with help of obtain signals, in addition to absorption
rate, the thickness or volume and therefrom, the density of items
in a object can be determined. From the absorption rate and the
density then the type of material of items in an object which have
just been transilluminated can be exactly determined.
[0015] Further benefits can be seen from the following description
of the drawings. Embodiments of the invention are shown in the
drawings which include numerous features of the invention in
combination. One of ordinary skill in the art can advantageously
use the individual features for putting together practical further
combinations. In the Drawings:
[0016] FIG. 1 is a concept schematic representation of an
apparatus;
[0017] FIG. 2 is a front view of a transillumination space;
[0018] FIG. 3 is a side view of the transillumination space of FIG.
2 without an object;
[0019] FIG. 4 is a preferred variant of the apparatus; and
[0020] FIG. 5 is a side view of the transillumination space of FIG.
4, without an object.
[0021] FIG. 1 shows a general view of an uncomplicated embodiment
of an apparatus 1 of this invention for transillumination of an
object 4, with a monitor 2, a transport track 3, an object 4 to be
transilluminated, as well as a transillumination space 5. An image
model of the object 4 is on a monitor 2 depicting items 4.1
contained therein.
[0022] Two different radiation sources 10, 30 are arranged in
different planes about the transport track 3, as can be seen in a
front view in FIG. 2 and in a side view in FIG. 3. Also, three
detector apparatus 11, 12, 31 are positioned above or below the
transport track 3. A double collimator, or two single collimators
13, 14 are arranged in front of the radiation source 10 to mask out
two ionized rays or beams FX1.1, FX1.2, for example two X-ray beams
of the same energy. A further collimator 32 is provided in front of
the radiation source 30 which thereby masks out only one ionized
beam FX3. Both of the detector structures 11, 12 are directed
toward the beams FX1.1, FX1.2 of the common radiation source 10,
such that they are arranged at an angle to one another. In a
space-saving embodiment, the beam FX3 crosses one of the two beams
FX1.1 or FX1.2 so that one of the two detector structures 11, 12 is
angularly displaced to the detector structure 31, or tilted
thereto, and is mounted to partly, or somewhat, be crossed
therewith; with "crossed" as used in this application also meaning
that the detector structure 31 can be perpendicular to the tilted
detector structure 11 or 12, in the above embodiment it being the
detector structure 12. As used in this application, angularly
displaced means that the beams FX1.1 and FX1.2 are radiated, or
masked, to diverge from one another at a predetermined angle
outwardly from a common focus point in the radiation source 10. By
inter-crossing the detector structures 12, 31, a space between the
two radiation sources 10, 30 can be reduced. A further space saving
can be had if the radiation source 30 is mounted so that the beam
FX3 also no longer extends perpendicular to the transport plane,
rather comes from above directly opposite the beam FX1.2. In this
case, the detector structure 31 and the detector structure 12 can
be mounted to be still further interspersed into one another. Also
an arrangement of the radiation source 30 beneath the transport
track 30 is possible in the same manner.
[0023] In a preferred embodiment according to FIGS. 4 and 5, three
radiation sources 10, 20, 30 are arranged in various planes, which
is particularly clearly illustrated in FIG. 5. In this regard,
there are five detector structures 11, 12, 21, 22, 31 above or
below the transport track 3. These detector structures 11, 12, 21,
22, 31 are preferable structured as L-shaped detector lines.
However, U-shaped detector line structures, as well as variations
of both types, are possible.
[0024] The two front, relative to a transport direction, radiation
sources 10, 20 are mounted to the right and the left, one after the
other, preferably below the transport apparatus 3. These are
assigned to the detector lines 11 and 12 as well as the detector
lines 21 and 22 that are aligned with the radiation sources 10, 20
above the transport apparatus 3. These radiation sources 10, 20 are
allocated to the collimators 13, 14 or 23, 24 through which the
relevant portion of the beam is allowed to pass a mask whereby two,
angularly-displaced beams FX1.1 and FX1.2 or FX2.1 and FX2.2 are
created. These beams FX1.1 and FX1.2 or FX2.1 and FX2.2 are
preferably formed as fanned rays. The collimators 13, 14 and 23, 24
are in this regard preferably structured as slit collimators. The
angled arrangement of the slit collimators 13, 14 or 23, 24 to one
another is, for example, carried out at an angle of 30.degree. to
90.degree.. The collimators 13 and 14 are thereby preferably
arranged almost parallel to the transport plane. With this
arrangement, four beam directions are simultaneously created with
only two radiation sources 10, 20.
[0025] The detector lines 12 and 21 are, as can be clearly seen in
FIG. 5, angularly displaced to be aligned with the beams FX1.2 or
FX2.1, whereby both detector lines 12, 21 are arranged to be
crossed within one another. In this manner, a space saving and
compact device 1 is provided. The more these detector lines 12, 21
are crossed within one another, the less space is necessary within
the device 1. It is beneficial for the detector cells 12 and 21 to
be crossed into one another at an angle of from 30.degree. to
around 60.degree..
[0026] A fifth beam FX3 for a fifth beam direction is created at a
radiation source 30 with the help of a further collimator 32 in
front of the radiation source 30. This third radiation source 30 is
accordingly preferably arranged above, for example above right, the
transport apparatus, for example in a rear space of the
transillumination space 5. The collimator 32, which is formed as a
slit collimator, thereby extends perpendicular to a transport plane
for creating a preferably fan shaped beam FX3. The detector line
31, which cooperates with the X-ray generator 30, is mounted below
the transport device 3.
[0027] The detector lines 11, 12, 21, 22, 31 of FIGS. 2 and 3 and
FIGS. 4 and 5 are coupled, in a known manner, with an electronic
processor (not shown in additional detail) for evaluating
traditionally signals created in the detector lines 11, 12, 21, 22,
31. Depending upon a decrease in intensity of the individual beams
FX1.1-FX3, different magnitude signals are thereby generated. In
this manner the object 4 to be transilluminated is transported
along the transport track, or transport device 3, through the
transillumination space 5 while the object 4 is transilluminated by
3 or 5 beams FX1.1-FX3 from three or five different directions.
This transillumination can be made visible as a model 6 on the
monitor 2 whereby the object 4 with the items 4.1 therein can be
depicted according to an appropriate process, also three
dimensionally.
[0028] Absorption, as well as the thickness or volumes of the item
4.1 in object 4 is determined from the signals created at the
detector lines 11, 12, 21, 22, 31. From the thickness or the
volume, the density can be determined. With these two measured
quantities, the processor, with the help of reference quantities
stored in the processor, can exactly determine the materials or the
material types.
[0029] It should be understood that the series arrangement of the
radiation sources 10, 20, 30 and the detector lines 11, 12, 21, 22,
31, as well as their mounting positions can be interchanged.
[0030] Further, the radiation sources 10, 20, 30 can be X-ray
generators, gamma-radiation generators and the like. If the created
beams FX1.1, FX1.2, FX2.1, FX2.2 as well as FX3 are X-ray beams,
the detector structures 11, 12, 21, 22, 31 are made as
scintillation detectors which are packaged as detector lines in a
normal manner.
[0031] In addition to the already described ray fans, so called
pencil beams can also, for example, be created in the normal manner
by masks and used for transillumination of the objects 4.
[0032] The described arrangement of apparatus 1 is not limited to
use in a hand luggage X-ray examination device. Such an arrangement
can also be used for larger container X-ray examination
installations and the like. Also, its use is not limited purely to
flight safety.
* * * * *