U.S. patent application number 17/354951 was filed with the patent office on 2021-11-18 for rotating structure for radiation imaging modalities.
The applicant listed for this patent is Analogic Corporation. Invention is credited to Andrew Alvino, Ronald E Swain, Tadas Vaisvila, Robert Williams.
Application Number | 20210353237 17/354951 |
Document ID | / |
Family ID | 1000005750081 |
Filed Date | 2021-11-18 |
United States Patent
Application |
20210353237 |
Kind Code |
A1 |
Williams; Robert ; et
al. |
November 18, 2021 |
ROTATING STRUCTURE FOR RADIATION IMAGING MODALITIES
Abstract
Among other things, a computed tomography (CT) imaging modality
is provided. The imaging modality includes a radiation source that
emits radiation. The imaging modality includes a detector array
that detects at least a portion of the radiation. The imaging
modality includes a rotating structure that rotates about an axis.
The rotating structure includes a first support portion having a
first shape. The rotating structure includes a second support
portion having a second shape different than the first shape. The
radiation source and the detector array are mounted to the second
support portion.
Inventors: |
Williams; Robert;
(Wilmington, MA) ; Alvino; Andrew; (Haverhill,
MA) ; Swain; Ronald E; (Reading, MA) ;
Vaisvila; Tadas; (Salem, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Analogic Corporation |
Peabody |
MA |
US |
|
|
Family ID: |
1000005750081 |
Appl. No.: |
17/354951 |
Filed: |
June 22, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16336452 |
Mar 25, 2019 |
11039798 |
|
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PCT/US2016/054309 |
Sep 29, 2016 |
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17354951 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16C 33/61 20130101;
A61B 6/035 20130101; F16C 19/183 20130101; F16C 2300/14 20130101;
A61B 6/4085 20130101; A61B 6/4429 20130101 |
International
Class: |
A61B 6/03 20060101
A61B006/03; A61B 6/00 20060101 A61B006/00; F16C 19/18 20060101
F16C019/18; F16C 33/61 20060101 F16C033/61 |
Claims
1. A computed tomography (CT) imaging modality, comprising: a
radiation source configured to emit radiation; a detector array
configured to detect at least a portion of the radiation; and a
rotating structure configured to rotate about an axis, the rotating
structure comprising: a first support portion defining a
substantially cylindrical interior cavity; and a second support
portion defining a non-cylindrical interior cavity, wherein the
radiation source and the detector array are mounted to the second
support portion, and wherein the first support portion is disposed
within the non-cylindrical interior cavity of the second support
portion.
2. The CT imaging modality of claim 1, wherein the second support
portion comprises a wall segment defining an opening that the
radiation source overlies to emit the radiation through the
opening, the wall segment comprising a wall portion, defining a
portion of the opening, having a non-constant thickness along a
length of the wall portion.
3. The CT imaging modality of claim 1, comprising an object support
configured to convey an object in a direction parallel to the axis
from an upstream portion of the CT imaging modality to a downstream
portion of the CT imaging modality, wherein the non-cylindrical
interior cavity defines the upstream portion of the CT imaging
modality and the substantially cylindrical interior cavity defines
the downstream portion of the CT imaging modality.
4. The CT imaging modality of claim 1, wherein the first support
portion comprises a substantially annular bearing for coupling the
rotating structure to a stationary support structure.
5. The CT imaging modality of claim 4, wherein: the first support
portion comprises a wall having an inner radial surface defining a
circumference of the substantially cylindrical interior cavity and
having an outer radial surface diametrically opposing the inner
radial surface, and the substantially annular bearing is disposed
on the outer radial surface.
6. The CT imaging modality of claim 1, wherein the rotating
structure comprises an intermediate attachment structure that
attaches to the first support portion and the second support
portion, the intermediate attachment structure lying in a plane
that is substantially perpendicular to the axis, and the
intermediate attachment structure being located between the first
support portion and the second support portion.
7. The CT imaging modality of claim 1, wherein the detector array
is disposed within the non-cylindrical interior cavity of the
second support portion.
8. The CT imaging modality of claim 1, wherein: the second support
portion comprises a wall having an inner surface that defines the
non-cylindrical interior cavity and an outer surface diametrically
opposing the inner surface, the wall defines an opening that
extends from the inner surface to the outer surface; and the
radiation source is mounted to the second support portion on the
outer surface and overlies the opening.
9. The CT imaging modality of claim 1, comprising a weight mounted
in the non-cylindrical interior cavity.
10. The CT imaging modality of claim 9, wherein the detector array
is disposed between the radiation source and the weight.
11. The CT imaging modality of claim 1, wherein: the second support
portion comprises a wall having an inner surface that defines the
non-cylindrical interior cavity, the wall comprises a first wall
segment and a second wall segment, an interior angle is defined by
an inner surface of the first wall segment that in part defines the
non-cylindrical interior cavity and an inner surface of the second
wall segment that in part defines the non-cylindrical interior
cavity, and the interior angle is an obtuse angle.
12. The CT imaging modality of claim 1, wherein the first support
portion and the second support portion are integrally formed.
13. A computed tomography (CT) imaging modality, comprising: a
radiation source configured to emit radiation; a detector array
configured to detect at least a portion of the radiation; and a
rotating structure configured to rotate about an axis, the rotating
structure comprising: a first support portion comprising a wall
defining a substantially cylindrical interior cavity, wherein the
wall of the first support portion has an outer radial surface,
diametrically opposing the substantially cylindrical interior
cavity, that has a circumference; and a second support portion
comprising a wall defining a non-cylindrical interior cavity,
wherein: the wall of the second support portion comprises a first
wall segment having an inner surface that in part defines the
non-cylindrical interior cavity, the inner surface of the first
wall segment lying in a first plane; the wall of the second support
portion comprises a second wall segment having an inner surface
that in part defines the non-cylindrical interior cavity, the inner
surface of the second wall segment lying in a second plane; and the
first support portion is disposed within the non-cylindrical
interior cavity of the second support portion.
14. The CT imaging modality of claim 13, wherein: an interior angle
is defined by the inner surface of the first wall segment and the
inner surface of the second wall segment, and the interior angle is
an obtuse angle.
15. The CT imaging modality of claim 13, wherein: the wall of the
second support portion has an inner surface that defines the
non-cylindrical interior cavity and an outer surface diametrically
opposing the inner surface, the wall defines an opening that
extends from the inner surface to the outer surface; and the
radiation source is mounted to the second support portion on the
outer surface and overlies the opening to emit the radiation
through the opening.
16. The CT imaging modality of claim 13, wherein the detector array
is disposed within the non-cylindrical interior cavity.
17. The CT imaging modality of claim 13, wherein the radiation
source and the detector array are mounted to the second support
portion.
18. The CT imaging modality of claim 13, comprising an object
support configured to convey an object in a direction parallel to
the axis from an upstream portion of the CT imaging modality to a
downstream portion of the CT imaging modality, wherein the
substantially cylindrical interior cavity defines the upstream
portion of the CT imaging modality and the non-cylindrical interior
cavity defines the downstream portion of the CT imaging
modality.
19. The CT imaging modality of claim 13, comprising an object
support configured to convey an object in a direction parallel to
the axis from an upstream portion of the CT imaging modality to a
downstream portion of the CT imaging modality, wherein the
non-cylindrical interior cavity defines the upstream portion of the
CT imaging modality and the substantially cylindrical interior
cavity defines the downstream portion of the CT imaging
modality.
20. The CT imaging modality of claim 13, wherein a substantially
annular bearing is disposed on the outer radial surface.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/336,452, filed Mar. 25, 2019, now U.S. Pat.
No. 11,039,798, issued on Jun. 22, 2021, which is a national phase
entry under 35 U.S.C. .sctn. 371 of PCT/US2016/054309, filed Sep.
29, 2016, designating the United States of America and published in
English as International Patent Publication WO 2018/063210 A1 on
Apr. 5, 2018, the disclosure of each of which is hereby
incorporated herein in its entirety by this reference.
TECHNICAL FIELD
[0002] The present application relates to a rotating structure for
radiation imaging modalities (e.g., imaging modalities that utilize
radiation to examine an object). It finds particular application in
the context of computed tomography (CT) scanners. However, the
features described herein are not intended to be limited to CT
applications and/or other radiation imaging applications.
BACKGROUND
[0003] Today, CT and other radiation imaging modalities (e.g.,
mammography, digital radiography, single-photon emission computed
tomography, etc.) are useful to provide information, or images, of
interior aspects of an object under examination. Generally, the
object is exposed to radiation (e.g., X-rays, gamma rays, etc.),
and an image(s) is formed based upon the radiation absorbed and/or
attenuated by the interior aspects of the object, or rather an
amount of radiation photons that is able to pass through the
object. Typically, highly dense aspects of the object (or aspects
of the object having a composition comprised of higher atomic
number elements) absorb and/or attenuate more radiation than less
dense aspects, and thus an aspect having a higher density (and/or
high atomic number elements), such as a bone or metal, for example,
will be apparent when surrounded by less dense aspects, such as
muscle or clothing.
[0004] Radiation imaging modalities generally comprise, among other
things, one or more radiation sources (e.g., an X-ray source,
Gamma-ray source, etc.) and a detector array comprised of a
plurality of pixels that are respectively configured to convert
radiation that has traversed the object into signals that may be
processed to produce the image(s). As an object is passed between
the radiation source(s) and the detector array, radiation is
absorbed/attenuated by the object, causing changes in the
amount/energy of detected radiation. Using information derived from
the detected radiation, radiation imaging modalities are configured
to generate images that can be used to detect items within the
object that may be of particular interest (e.g., body
characteristics, threat items, etc.). These images may be
two-dimensional images or three-dimensional images.
[0005] To generate three-dimensional images, at least one of the
radiation sources or the detector array is rotated relative to the
object under examination to acquire information about the object
from various views. In CT scanners, the radiation source(s) and the
detector array are typically mounted to a disk or drum that is
rotated about the object under examination. These disks or drums
must be sized to accommodate the object (e.g., luggage, a human
patient, etc.) in a center bore, and thus the outer diameter of
such disks or drums may exceed five feet.
[0006] Moreover, in some applications, such as in medical
applications where minimal movement by the patient is desired
during the imaging process applications, these disks or drums must
spin at speeds in excess of 100 revolutions per minute (RPM) to
shorten the time that the patient is required to be still. At such
speeds, the disk or drum may be subjected to relatively large
inertial loads that can cause deflection between the radiation
source(s) and the detector array. Further, these inertial loads may
cause deflection within support bearings of the rotating structure.
The algorithms used to reconstruct the images from the information
generated about detected radiation rely on a precise alignment
between the radiation source(s) and the detector array, and thus
such deflection can cause unwanted vibrations that result in
reduced image quality.
BRIEF SUMMARY
[0007] Aspects of the present application address the above
matters, and others. According to one aspect a computed tomography
(CT) imaging modality is provided. The imaging modality comprises a
radiation source configured to emit radiation and a detector array
configured to detect at least a portion of the radiation. The
imaging modality further comprises a rotating structure configured
to rotate about an axis. The rotating structure comprises a first
support portion defining a substantially cylindrical interior
cavity. The rotating structure also comprises a second support
portion defining a non-cylindrical interior cavity. The radiation
source and the detector array are mounted to the second support
portion.
[0008] According to another aspect, a computer tomography (CT)
imaging modality comprises a radiation source configured to emit
radiation and a detector array configured to detect at least a
portion of the radiation. The imaging modality also comprises a
rotating structure configured to rotate about an axis. The rotating
structure comprises a first support portion comprising a wall
defining a substantially cylindrical interior cavity. The wall of
the first support portion has an outer radial surface,
diametrically opposing the substantially cylindrical interior
cavity, which has a circumference. The rotating structure also
comprises a second support portion comprising a wall defining a
non-cylindrical interior cavity. The wall of the second support
portion comprises a first wall segment having an inner surface that
in part defines the non-cylindrical interior cavity. The inner
surface of the first wall segment lies in a first plane. The wall
of the second support portion comprises a second wall segment
having an inner surface that in part defines the non-cylindrical
interior cavity. The inner surface of the second wall segment lies
in a second plane.
[0009] According to another aspect, a computed tomography (CT)
imaging modality comprises a radiation source configured to emit
radiation and a detector array configured to detect at least a
portion of the radiation. The imaging modality also comprises a
rotating structure configured to rotate about an axis. The rotating
structure comprises a support portion comprising a wall defining a
non-cylindrical interior cavity. The wall of the support portion
comprises a first wall segment having an inner surface that in part
defines the non-cylindrical interior cavity. The inner surface of
the first wall segment lies in a first plane. The wall of the
support portion comprises a third wall segment having an inner
surface that in part defines the non-cylindrical interior cavity.
The inner surface of the third wall segment lies in a third plane.
The third wall segment diametrically opposes the first wall segment
relative to the non-cylindrical interior cavity. The radiation
source and detector array lie along a second axis perpendicular to
the axis. A distance between the first wall segment and the third
wall segment at a first location along the second axis is different
than a distance between the first wall segment and the third wall
segment at a second location along the second axis.
[0010] Those of ordinary skill in the art will appreciate still
other aspects of the present application upon reading and
understanding the appended description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The application is illustrated by way of example and not
limitation in the figures of the accompanying drawings, in which
like references generally indicate similar elements and in
which:
[0012] FIG. 1 illustrates an example environment of an imaging
modality.
[0013] FIG. 2 illustrates an example rotating structure having a
first support portion and a second support portion.
[0014] FIG. 3 illustrates an example second support portion of a
rotating structure having an interior cavity.
[0015] FIG. 4 illustrates an example rotating structure comprising
a radiation source and a detector array mounted to a second support
portion.
DETAILED DESCRIPTION
[0016] The claimed subject matter is now described with reference
to the drawings, wherein like reference numerals are generally used
to refer to like elements throughout. In the following description,
for purposes of explanation, numerous specific details are set
forth in order to provide a thorough understanding of the claimed
subject matter. It may be evident, however, that the claimed
subject matter may be practiced without these specific details. In
other instances, structures and devices are illustrated in block
diagram form in order to facilitate describing the claimed subject
matter.
[0017] The present disclosure relates to a rotating structure upon
which the radiation source and the detector array are mounted. The
rotating structure is shaped so as to reduce deflections in
structurally significant regions (e.g., regions of the rotating
structure where deflections would be felt by the radiation source
and/or detector array). As will be described in more detail
throughout the disclosure, the rotating structure comprises a first
support portion and a second support portion. In some embodiments,
the first support portion is substantially cylindrical. Bearings
are mounted to the first support portion and couple the rotating
structure to a stationary support structure. In some embodiments,
the second support portion is non-cylindrical (e.g., triangular or
"A-framed"). The radiation source and the detector array are
mounted to the second support portion.
[0018] FIG. 1 is an illustration of an example environment 100
comprising an example radiation imaging modality that may be
configured to generate data (e.g., images) representative of an
object 102 or aspect(s) thereof under examination. It will be
appreciated that the features described herein may find
applicability to other imaging modalities besides the example
computed tomography (CT) scanner illustrated in FIG. 1. For
example, the rotating structure 104 described herein may find
applicability to other types of radiation imaging modalities, such
SPECT modalities. Moreover, the arrangement of components and/or
the types of components included in the example environment 100 are
for illustrative purposes only. For example, the rotating structure
104 (e.g., a rotating gantry) may comprise additional components to
support the operation of a radiation source 118 and/or detector
array 106, such as a cooling unit, power units, etc. As another
example, at least a portion of a data acquisition component 122 may
be comprised within and/or attached to the detector array 106.
[0019] In the example environment 100, an examination unit 108 of
the imaging modality is configured to examine one or more objects
102. The examination unit 108 can comprise a rotating structure 104
and a (stationary) support structure 110, also referred to herein
as a frame, which may encase and/or surround as least a portion of
the rotating structure 104 (e.g., as illustrated with an outer,
stationary ring, surrounding an outside edge of an inner, rotating
ring). During an examination of the object(s) 102, the object(s)
102 can be placed on an object support 112, such as a bed or
conveyor belt, for example, that is selectively positioned in an
examination region 114 (e.g., a hollow bore in the rotating
structure 104), and the rotating structure 104 can be rotated
and/or supported about the object(s) 102 by a rotator 116, such as
a bearing, motor, belt drive unit, drive shaft, chain, roller
truck, etc.
[0020] The rotating structure 104 may surround a portion of the
examination region 114 and may comprise one or more radiation
sources 118 (e.g., an ionizing X-ray source, gamma radiation
source, etc.) and a detector array 106 that is mounted on a
substantially diametrically opposite side of the rotating structure
104 relative to the radiation source(s) 118.
[0021] During an examination of the object(s) 102, the radiation
source(s) 118 emits fan, cone, wedge, and/or other shaped radiation
120 configurations from a focal spot(s) of the radiation source(s)
118 (e.g., a region within the radiation source(s) 118 from which
radiation 120 emanates) into the examination region 114. It will be
appreciated that such radiation 120 may be emitted substantially
continuously and/or may be emitted intermittently (e.g., a brief
pulse of radiation is emitted followed by a resting period during
which the radiation source 118 is not activated).
[0022] As the emitted radiation 120 traverses the object(s) 102,
the radiation 120 may be attenuated differently by different
aspects of the object(s) 102. Because different aspects attenuate
different percentages of the radiation 120, an image(s) may be
generated based upon the attenuation, or variations in the number
of photons that are detected by the detector array 106. For
example, more dense aspects of the object(s) 102, such as a bone or
metal plate, may attenuate more of the radiation 120 (e.g., causing
fewer photons to strike the detector array 106) than less dense
aspects, such as skin or clothing.
[0023] The detector array 106 can comprise a linear (e.g.,
one-dimensional) or two-dimensional array of elements (sometimes
referred to as pixels or channels) disposed as a single row or
multiple rows in the shape of spherical arc, typically having a
center of curvature at the focal spot of the radiation source(s)
118, for example. As the rotating structure 104 rotates, the
detector array 106 is configured to directly convert (e.g., using
amorphous selenium and/or other direct conversion materials) and/or
indirectly convert (e.g., using Cesium Iodide (CsI) and/or other
indirect conversion materials) detected radiation into electrical
signals.
[0024] Signals that are produced by the detector array 106 may be
transmitted to a data acquisition component 122 that is in operable
communication with the detector array 106. Typically, the data
acquisition component 122 is configured to convert the electrical
signals output by the detector array 106 into digital data and/or
to combine the digital data acquired during a measuring interval.
The collection of digital output signals for a measuring interval
may be referred to as a "projection" or a "view."
[0025] The example environment 100 also illustrates an image
reconstructor 124 that is operably coupled to the data acquisition
component 122 and is configured to generate one or more images
representative of the object 102 under examination based at least
in part upon signals output from the data acquisition component 122
using suitable analytical, iterative, and/or other reconstruction
technique (e.g., tomosynthesis reconstruction,
back-projection,iterative reconstruction, etc.).
[0026] The example environment 100 also includes a terminal 126, or
workstation (e.g., a computer), configured to receive image(s) from
the image reconstructor 124, which can be displayed on a monitor
128 to a user 130 (e.g., security personnel, medical personnel,
etc.). In this way, the user 130 can inspect the image(s) to
identify areas of interest within the object(s) 102. The terminal
126 can also be configured to receive user input which can direct
operations of the object examination unit 108 (e.g., a speed of
rotation for the rotating structure 104, an energy level of the
radiation, etc.).
[0027] In the example environment 100, a controller 132 is operably
coupled to the terminal 126. In one example, the controller 132 is
configured to receive user input from the terminal 126 and generate
instructions for the examination unit 108 indicative of operations
to be performed.
[0028] It will be appreciated that the example component diagram is
merely intended to illustrate one embodiment of one type of imaging
modality and is not intended to be interpreted in a limiting
manner. For example, the functions of one or more components
described herein may be separated into a plurality of components
and/or the functions of two or more components described herein may
be consolidated into merely a single component. Moreover, the
imaging modality may comprise additional components to perform
additional features, functions, etc. (e.g., such as automatic
threat detection).
[0029] FIG. 2 illustrates an example of the rotating structure 104
that can be used within the example environment 100 of FIG. 1. The
rotating structure 104 can rotate about an axis 200 (e.g.,
extending in the z-direction). In an example, the rotating
structure 104 comprises a first support portion 202 and a second
support portion 204. The first support portion 202 and the second
support portion 204 can be attached to each other via fasteners
(e.g., screws, rivets, etc.) or can be integrally formed as a
one-piece structure. As such, the first support portion 202 and the
second support portion 204 can simultaneously rotate about the axis
200. The first support portion 202 and the second support portion
204 may comprise any number of materials, such as metals,
non-metals, composites, etc.
[0030] In some embodiments, the first support portion 202 defines a
substantially cylindrical first interior cavity 206. In an example,
the first support portion 202 may comprise a wall 208 that defines
the first interior cavity 206. The axis 200 can extend through a
center of the first interior cavity 206, such that the wall 208 is
separated a substantially constant distance (e.g., a radial
distance) from the axis 200 about a circumference of the wall 208.
That is, in an example, the axis 200 may be separated from the wall
208 a first distance at a first circumferential location of the
wall 208, and a second distance at a second circumferential
location of the wall 208. In such an example, the first distance
and the second distance may be substantially equal.
[0031] The wall 208 comprises an inner radial surface 210 and an
outer radial surface 212. The inner radial surface 210 can define a
circumference of the substantially cylindrical first interior
cavity 206. The outer radial surface 212 may diametrically oppose
the inner radial surface 210. That is, in an example, the inner
radial surface 210 may be located in closer proximity to the axis
200 than the outer radial surface 212.
[0032] The wall 208 comprises an intermediate surface 214 that
interfaces with the inner radial surface 210 and the outer radial
surface 212. By interfacing with the inner radial surface 210 and
the outer radial surface 212, the intermediate surface 214 may form
an angle with respect to the inner radial surface 210 and the outer
radial surface 212. In an example, the angle may be between about
80 degrees and about 100 degrees, such as by being about 90
degrees. In the illustrated example, the intermediate surface 214
may define an end of the first support portion 202 along the axis
200 that is opposite the second support portion 204.
[0033] The first support portion 202 may comprise one or more
substantially annular bearings 220 for coupling the rotating
structure 104 to the stationary support structure 110. In an
example, the substantially annular bearings 220 may be disposed on
the outer radial surface 212 of the wall 208. Due to the
substantially annular shape of the annular bearings 220 and the
substantially annular shape of the outer radial surface 212, the
rotating structure 104 can rotate about the axis 200. It may be
appreciated that while the annular bearings 220 (e.g., the ball
bearings) may be disposed on the outer radial surface 212 and may
contact the outer radial surface 212, in some embodiments a bearing
support structure that is configured to maintain the position of
the annular bearing 220 may be attached to an to an axial surface
213 adjacent the outer radial surface 212. For example, the bearing
support structure may be substantially L-shaped, with a first
surface of the bearing support structure pressing the annular
bearing 220 against the outer radial surface 212 (e.g., the annular
bearings 220 are disposed between the first surface of the bearing
support structure and the outer radial surface 212) and a second
surface of the bearing support structure being secured to the axial
surface 213.
[0034] Referring to FIGS. 2 and 3, the first support portion 202
can be attached to the second support portion 204 by an
intermediate wall 250. The intermediate wall 250 can lie in a plane
that is substantially perpendicular to the axis 200 (e.g., lying in
an x,y plane). The intermediate wall 250 can define an opening 251
that substantially matches a size and location of the first
interior cavity 206. In an example, the intermediate wall 250 can
be attached to or formed with the first support portion 202 at an
inner location. The intermediate wall 250 can be attached to or
formed with the second support portion 204 at an outer location. As
such, due to the attachment between the first support portion 202,
the intermediate wall 250, and the second support portion 204, the
rotating structure 104 can define a substantially fixed and/or
static structure that exhibits reduced or limited deformation,
deflection, and/or vibration when the rotating structure 104 is
rotated about the axis 200. In some examples, the intermediate wall
250 defines one or more wall openings 252. The wall openings 252
can assist in receiving one or more structures or components that
may be attached to the rotating structure 104 and/or can allow for
airflow that helps cool components disposed within the second
support portion 204 of the rotating structure 104.
[0035] In an example, one or more rigid structures 254 may be
provided as part of the intermediate wall 250 to increase the
rigidity of the intermediate wall 250. In such an example, the
rigid structures 254 can extend through the intermediate wall 250
adjacent to the wall openings 252. The rigid structures 254 can
comprise a thicker and/or denser material than surrounding walls so
as to reduce deformation, deflection, and/or vibration between the
first support portion 202 and the second support portion 204. In an
example, the rigid structures 254 can extend substantially
perpendicularly with respect to the axis 200.
[0036] Referring to FIG. 3, a rear perspective view of the rotating
structure 104 is illustrated. In an example, the second support
portion 204 can define a non-cylindrical second interior cavity
300. In an example, the second support portion 204 may comprise a
wall 302 that defines the non-cylindrical second interior cavity
300, with the wall 302 extending substantially about the axis 200.
The second interior cavity 300 is adjacent to the first interior
cavity 206, such that the axis 200 can intersect and extend through
both the first interior cavity 206 and the second interior cavity
300.
[0037] In an example, the first interior cavity 206 and the second
interior cavity 300 can have different, non-matching shapes. For
example, the first interior cavity 206 can have a substantially
circular shape or cylindrical shape. The second interior cavity 300
can have a non-circular shape or non-cylindrical shaped defined by
one or more substantially linear sidewalls. In addition, the first
interior cavity 206 can have a different cross-sectional size
(e.g., as measured along a plane that is substantially
perpendicular to the axis 200) than the second interior cavity 300.
For example, a cross-sectional size of the first interior cavity
206 (e.g., an area of the first interior cavity 206) may be less
than a cross-sectional size of the second interior cavity 300.
[0038] The wall 302 comprises an inner surface 304 and an outer
surface 306. The inner surface 304 defines the non-cylindrical
second interior cavity 300. The outer surface 306 may diametrically
oppose the inner surface 304. That is, in an example, the inner
surface 304 may be located in closer proximity to the axis 200 than
the outer surface 306 at a location.
[0039] The wall 302 may define one or more openings 308 that extend
from the inner surface 304 to the outer surface 306. In an example,
the opening 308 can define gaps, spaces, cavities, or the like
formed within the wall 302. The openings 308 can be provided so as
to receive and/or support one or more structures, components, or
the like within the wall 302.
[0040] The wall 302 may comprise one or more wall segments 310. In
an example, a plurality of wall segments 310 may be provided, with
adjacent wall segments 310 forming an interior angle that is
between about 0 degrees to about 180 degrees. The wall segments 310
in the illustrated example are substantially planar, though the
wall segments 310 may have bends, curves, undulations, or other
non-planar shapes. In an example, some or all of the wall segments
310 may comprise non-equal lengths 312, 314, such that some wall
segments 310 may be shorter or longer in length than other wall
segments 310. In other examples, the wall segments 310 may have
substantially similar or identical lengths. In this example, the
lengths 312, 314 of the wall segments 310 may be defined as
extending along a direction that is substantially perpendicular to
the axis 200.
[0041] While the example second support portion 204 of FIG. 3
comprises six wall segments 310, any number may be provided. The
wall segments 310 can extend a distance along the axis 200 (e.g.,
between an upstream end and a downstream end of the second support
portion 204). The size of the wall segments 310 along the axis 200
can function to reduce deformation, deflection, and/or vibration of
the rotating structure 104. For example, the wall segments 310 can
support one or more structures or components, while being
relatively resistant to deformation, deflection, and/or vibration
during rotation of the rotating structure 104.
[0042] The wall segments 310 comprise a first wall segment 320 and
a second wall segment 330. The first wall segment 320 has an inner
surface 322 that, in part, defines the second interior cavity 300.
In an example, the inner surface 322 of the first wall segment 320
lies in a first plane 324. The second wall segment 330 has an inner
surface 332 that, in part, defines the second interior cavity 300.
In an example, the inner surface 332 of the second wall segment 330
lies in a second plane 334. In some examples, the first plane 324
and the second plane 334 may be non-parallel.
[0043] In an example, an interior angle 340 may be defined by the
inner surface 322 of the first wall segment 320 that, in part,
defines the non-cylindrical second interior cavity 300, and the
inner surface 332 of the second wall segment 330 that, in part,
defines the non-cylindrical second interior cavity 300. In an
example, the interior angle 340 may be an obtuse angle (e.g., an
angle that is between about 90 degrees and 180 degrees). In an
example, some or all of the interior angles defined by inner
surfaces of adjacent wall segments may be obtuse angles.
[0044] The wall segments 310 may comprise a third wall segment 350.
The third wall segment 350 has an inner surface 352 that, in part,
defines the second interior cavity 300. In an example, the inner
surface 352 of the third wall segment 350 lies in a third plane
354. The third plane 354 may not be co-planar with respect to the
first plane 324 and/or the second plane 334. In an example, the
third plane 354 may extend non-parallel with respect to the first
plane 324 and/or the second plane 334.
[0045] The third wall segment 350 may diametrically oppose the
first wall segment 320 relative to the non-cylindrical second
interior cavity 300. In an example, the first wall segment 320 and
the third wall segment 350 may be separated a first distance 356 at
a first location 358. The first distance 356 may be measured at a
location along a second axis 360 (e.g., perpendicular to the second
axis 360) that is perpendicular to the axis 200. In an example, the
first wall segment 320 and the third wall segment 350 may be
separated a second distance 359 at a second location 363. The
second distance 359 may be measured at the second location 363
along the second axis 360 (e.g., perpendicular to the second axis
360). In an example, the first distance 356 may be different than
the second distance 359. For example, the first wall segment 320
and the third wall segment 350 can have a gradually increasing
distance from each other as measured from first ends 370, 372 of
the first wall segment 320 and the third wall segment 350,
respectively, to second ends 374, 376 of the first wall segment 320
and the third wall segment 350, respectively.
[0046] The wall segments 310 may comprise a fourth wall segment
361. The fourth wall segment 361 may extend between the first wall
segment 320 and the third wall segment 350. In an example, the
fourth wall segment 361 may be attached at a first end to the first
wall segment 320 and at a second end to the third wall segment
350.
[0047] The fourth wall segment 361 can comprise a first wall
portion 362, a second wall portion 364, a third wall portion 366,
and a fourth wall portion 368. The first wall portion 362 and the
second wall portion 364 can extend substantially parallel to each
other and may be spaced apart to partially define a wall opening
380. In an example, the first wall portion 362 and the second wall
portion 364 can extend between the first wall segment 320 and the
third wall segment 350 (e.g., perpendicular to the second axis
360).
[0048] The third wall portion 366 and the fourth wall portion 368
can extend substantially parallel to each other and may be spaced
apart to partially define the wall opening 380. In an example, the
third wall portion 366 and the fourth wall portion 368 can extend
along the axis 200 in a direction that is substantially
perpendicular to the first wall portion 362 and the second wall
portion 364. In an example, the first wall portion 362 and the
second wall portion 364 may have a substantially similar first
length, while the third wall portion 366 and the fourth wall
portion 368 may have a substantially similar second length. The
first length may be greater than the second length, such that the
wall opening 380 defined by the wall portions 362, 364, 366, 368
has a substantially rectangular shape.
[0049] The first wall portion 362 and the second wall portion 364
can have a thickness 382 that is non-constant along the first
length of the first wall portion 362 and the second wall portion
364. For example, the thickness 382 may be larger at ends of the
first wall portion 362 and the second wall portion 364 than at a
center of the first wall portion 362 and the second wall portion
364. In the illustrated example, the thickness 382 of the first
wall portion 362 and the second wall portion 364 may be at a
minimum towards a center, while gradually increasing towards ends
of the first wall portion 362 and the second wall portion 364 so as
to define an arched shape. Such a shape can accommodate for the
first interior cavity 206 so as to not impede and/or block the
first interior cavity 206.
[0050] It will be appreciated that while some wall segments (e.g.,
320, 350) of the second support portion 204 may be non-parallel to
each other, at least some wall segments of the second support
portion 204 may be substantially parallel to each other. For
example, the fourth wall segment 361 may be substantially parallel
to a wall segment 310 that is diametrically opposed to the fourth
wall segment 361 (e.g., a bottom wall segment).
[0051] Referring to FIG. 4, the rotating structure 104 is
illustrated supporting a plurality of components 400. In an
example, the radiation source 118 and the detector array 106 may be
mounted to the second support portion 204. For example, the
radiation source 118 and the detector array 106 may lie along the
second axis 360 that is perpendicular to the axis 200.
[0052] The radiation source 118 may be mounted to one of the wall
segments 310 of the second support portion 204. For example, the
radiation source 118 may be mounted to the fourth wall segment 361
adjacent to and/or received within the wall opening 380 (e.g.,
illustrated in FIG. 3) defined by the wall portions 362, 364, 366,
368 (e.g., illustrated in FIG. 3). In an example, the radiation
source 118 may be mounted to the second support portion 204 on the
outer surface 306 of the second support portion 204, and may
overlie the wall opening 380 to emit the radiation through the wall
opening 380.
[0053] The detector array 106 may be disposed within the second
interior cavity 300 of the second support portion 204. In an
example, the detector array 106 can be attached to the intermediate
wall 250 diametrically opposed from the radiation source 118. As
such, the detector array 106 and the radiation source 118 may be
spaced apart about 180 degrees about the first interior cavity 206.
The detector array 106 can be attached to the intermediate wall 250
in any number of ways, such as by fasteners or the like.
[0054] Moreover, in some embodiments, a surface of the intermediate
wall 250 upon which the detector array 106 is attached can be
diametrically opposite a surface of the intermediate wall 250 that
abuts the first support portion 202. In this way, for example, the
detector array 106 may be spaced apart from the first support
portion 202 and/or the annular bearing 220 that are in contact with
the first support portion 202. In some embodiments, by spacing the
detector array 106 away from the annular bearing few to none of the
vibrations caused by the annular bearing 220 are transferred to the
detector array 106 and/or those vibrations that are transferred are
damped due to the distance between the annular bearing 220 and the
detector array 106 and/or the material disposed therein.
[0055] In an example, one or more weights 402 may be mounted in the
non-cylindrical second interior cavity 300. The weights 402 can be
mounted to one or more of the wall segments 310, such as to the
inner surface 304 of the wall segments 310. The detector array 106
may be disposed between the radiation source 118 and the weights
402. In an example, the weights 402 can balance and/or offset the
weight of the radiation source 118 so as to reduce deformation,
deflection, and/or vibration when the rotating structure 104 is
rotated about the axis 200.
[0056] The object support 112 is configured to convey an object in
a direction that is substantially parallel to the axis 200 from an
upstream portion of the CT imaging modality to a downstream portion
of the CT imaging modality. In an example, the first interior
cavity 206 defines an upstream portion of the CT imaging modality
while the second interior cavity 300 defines a downstream portion
of the CT imaging modality. In another example, the second interior
cavity 300 defines the upstream portion of CT imaging modality
while the first interior cavity 206 defines the downstream portion
of the CT imaging modality.
[0057] During an examination, the object support 112 can support an
object 102. The object support 112 can be moved within and/or
through the first interior cavity 206 defined by the first support
portion 202 and the second interior cavity 300 defined by the
second support portion 204. As such, the object support 112 can be
positioned between the radiation source 118 and the detector array
106. The rotating structure 104 can be rotated about the object
support 112 as the radiation source 118 emits radiation into the
second interior cavity 300. The radiation 120 may be attenuated by
different aspects of the object(s) 102 supported on the object
support 112 and detected by the detector array 106.
[0058] The size, shape, and/or geometry of the rotating structure
104 can reduce deformation, deflection, and/or vibration that may
be experienced by the radiation source 118 and the detector array
106. For example, wall segments 310 of the rotating structure 104
are arranged to form a partially symmetric shape (e.g., symmetric
about the second axis 360 but asymmetric about an axis that is
perpendicular to the first axis 200 and the second axis 360 and
bisects the second support portion 204) that can reduce vibration.
Additionally, the wall segments 310 extend a distance along the
first axis 200 that provides additional rigidity and strength to
the second support portion 204. Further, the rigid structures 254
can extend between the first support portion 202 and the second
support portion 204 so as to reduce deformation and/or vibration
between the first support portion 202 and the second support
portion 204. As a result of the reduced deformation, deflection,
and/or vibration, image quality obtained from the detector array
106 may be improved.
[0059] It may be appreciated that "example" and/or "exemplary" are
used herein to mean serving as an example, instance, or
illustration. Any aspect, design, etc., described herein as
"example" and/or "exemplary" is not necessarily to be construed as
advantageous over other aspects, designs, etc. Rather, use of these
terms is intended to present concepts in a concrete fashion. As
used in this application, the term "or" is intended to mean an
inclusive "or" rather than an exclusive "or." That is, unless
specified otherwise, or clear from context, "X employs A or B" is
intended to mean any of the natural inclusive permutations. That
is, if X employs A; X employs B; or X employs both A and B, then "X
employs A or B" is satisfied under any of the foregoing instances.
In addition, the articles "a" and "an" as used in this application
and the appended claims may generally be construed to mean "one or
more" unless specified otherwise or clear from context to be
directed to a singular form. Also, at least one of A and B or the
like generally means A or B or both A and B.
[0060] Although the disclosure has been shown and described with
respect to one or more implementations, equivalent alterations and
modifications will occur to others skilled in the art based upon a
reading and understanding of this specification and the annexed
drawings. The disclosure includes all such modifications and
alterations and is limited only by the scope of the following
claims. In particular regard to the various functions performed by
the above described components (e.g., elements, resources, etc.),
the terms used to describe such components are intended to
correspond, unless otherwise indicated, to any component which
performs the specified function of the described component (e.g.,
that is functionally equivalent), even though not structurally
equivalent to the disclosed structure which performs the function
in the herein illustrated example implementations of the
disclosure. Similarly, illustrated ordering(s) of acts is not meant
to be limiting, such that different orderings comprising the same
of different (e.g., numbers) of acts are intended to fall within
the scope of the instant disclosure. In addition, while a
particular feature of the disclosure may have been disclosed with
respect to only one of several implementations, such feature may be
combined with one or more other features of the other
implementations as may be desired and advantageous for any given or
particular application. Furthermore, to the extent that the terms
"includes," "having," "has," "with," or variants thereof are used
in either the detailed description or the claims, such terms are
intended to be inclusive in a manner similar to the term
"comprising."
* * * * *