KR20180070251A - X-ray Imaging Apparatus - Google Patents

Abstract

The present invention relates to a device for providing a computer tomography image and, more specifically, to an X-ray image photographing device capable of being suitable for miniaturization by separating rotation trajectories of an X-ray generator and an X-ray detector. The X-ray image photographing device comprises an X-ray generator unit and an X-ray detector unit. The X-ray generator unit rotates a position of an X-ray emission focus along a first trajectory on a first plane which is vertical to an ordinate shaft of a subject and emits an X-ray beam. The X-ray detector unit receives the X-ray beam at a light receiving position facing the X-ray emission focus where the ordinate shaft of the subject is interposed along a second trajectory on a second plane which is different from the first plane. The first plane and the second plane are parallel to each other. Each of the first trajectory and the second trajectory may be closed loop type trajectories based on the ordinate shaft of the subject.

Description

X-ray Imaging Apparatus

The present invention relates to an X-ray imaging apparatus, and more particularly, to a miniaturized X-ray imaging apparatus capable of providing a three-dimensional tomographic X-ray image, that is, a computed tomography (CT) image.

In the medical field, an X-ray imaging apparatus refers to a device that transmits a predetermined amount of X-rays to a body part of a person or an animal to be photographed, detects the transmitted X-rays with an X-ray detector, and forms an X-ray image based on the sensed electrical signals . The X-rays are attenuated and transmitted at different attenuation rates depending on the material on the path, and when they reach the X-ray detector, they are converted into electrical signals by photoelectric effect. The X-ray photographing apparatus provides information about the inside of the object to be photographed as an X-ray image by using an electrical signal reflecting the cumulative attenuation amount along the X-ray path. X-ray images include two-dimensional x-ray images and three-dimensional x-ray images. Typically, a two-dimensional x-ray image is provided through a two-dimensional x-ray imaging apparatus and a three-dimensional image is provided through a computerized tomography apparatus.

Computed tomography (CT) is the reconstruction of multiple x-ray images through computer mathematical calculations to provide a cross-sectional image of the body. It not only reveals the body tissue in detail, It is an X-ray imaging technique that allows accurate identification. When a plurality of tomographic images are sequentially stacked, a three-dimensional x-ray image containing information on the internal tissues of the body can be provided.

In the basic imaging principle of CT, in a rotating part of a gantry in which an X-ray generator and an X-ray detector are opposed to each other at a constant speed, an X-ray generator generates a fan beam or a cone ray beam to the patient. Then, the attenuation rate of the radiation differs depending on the body part of the patient. By measuring the X-ray reaching the X-ray detector in this way, the distribution of the attenuation rate for each body part can be constituted by the image. In the conventional computer tomography apparatus, the X-ray generator and the X-ray detector rotate along the same plane trajectory with the inspected object therebetween. It is general that the x-ray detector rotates along a locus close to the subject and the x-ray generator rotates along the outward trajectory because the magnification increases as the x-ray detector moves away from the longitudinal axis of the subject.

However, this configuration has a limitation in miniaturization of the X-ray imaging apparatus. There is a possibility that the X-ray generator and the X-ray detector are interfered with each other by their loci, and the means for rotating them may obstruct the travel path of the X-ray beam.

An object of the present invention is to provide an apparatus for providing a computer tomography image and an X-ray imaging apparatus suitable for miniaturization by separating the rotation loci of the X-ray generator and the X-ray detector from each other .

Another object of the present invention is to provide an X-ray imaging apparatus configured such that one or both of the X-ray generator and the X-ray detector are not obstructed by the progress of the X-ray beam even if the X- .

In order to solve the above-described problems, an X-ray imaging apparatus according to the present invention is an X-ray imaging apparatus that includes an X-ray imaging optical system for radiating an X-ray beam, which rotates along a first trajectory on a first plane perpendicular to a longitudinal axis of the subject, A generator section; And an X-ray detector for receiving the X-ray beam at a light receiving position opposite to the X-ray emitting focus with the longitudinal axis of the inspected object in a second locus on a second plane different from the first plane; .

The first plane and the second plane may be parallel to each other, and the first locus and the second locus may be a closed loop type locus centered on a vertical axis of the subject.

The light receiving surface of the X-ray detector portion may be perpendicular to the center line of the X-ray X-ray beam.

The x-ray generator portion may include a plurality of x-ray source units fixedly installed on the first locus, and driven in conjunction with a position where the x-ray detector receives the x-ray.

The x-ray detector unit may include a rotary detector array having two or more detector units and being rotationally driven along the second locus.

The X-ray detector includes a fixed detector array including a plurality of detector units fixedly arranged along the second locus, and selectively drives a corresponding one of the plurality of detector units according to a position of the X-ray emission focus X-rays can be received.

According to the present invention, in the X-ray image photographing apparatus for providing a computer tomography image, the rotation loci of the X-ray generator and the X-ray detector are separated on different planes, which is advantageous for miniaturization of the apparatus.

According to the present invention, even if one or both of the X-ray generator and the X-ray detector is installed in the form of a fixed structure rather than a rotating structure, it is possible to prevent the progress of the X-ray beam, It is possible to drastically reduce the occurrence of mechanical vibration in the apparatus.

FIG. 1 schematically shows a configuration of an X-ray imaging apparatus according to an embodiment of the present invention.
FIG. 2 schematically shows a cross section and a longitudinal section of an X-ray imaging apparatus according to an embodiment of the present invention.
FIG. 3 shows the trajectory of the X-ray source and the trajectory of the X-ray detector when photographing the X-ray in the embodiment of FIG.
4 schematically shows a cross-sectional view of an x-ray imaging apparatus according to an embodiment of the present invention.
5 schematically shows a cross-sectional view of an x-ray imaging apparatus according to an embodiment of the present invention.
FIG. 6 schematically shows a longitudinal section of an X-ray imaging apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below can be modified into various forms, and the scope of the present invention is not limited to the following embodiments. In other words, embodiments of the present invention are provided to clearly convey the technical idea of the invention to those skilled in the art.

FIG. 1 schematically shows a configuration of an X-ray imaging apparatus according to an embodiment of the present invention.

The X-ray imaging apparatus according to the present embodiment may have the same shape as a conventional medical CT imaging apparatus (a computer tomography apparatus). There is provided a donut-shaped gantry housing 10 accommodating a photographing section and a body 20 bed disposed at a central hole portion of the gantry housing 10 to support the inspected object. The gantry housing 10 is provided therein with an x-ray generator portion 11 for irradiating an x-ray beam X toward a subject and an x-ray beam X disposed on the opposite side of the x- And an X-ray detector portion 12 for providing an electrical signal corresponding thereto is disposed.

Here, the x-ray generator unit 11 includes an x-ray source unit, for example, a thermoelectron emission type or field emission type x-ray tube, and a mechanical driving system for moving the x-ray tube along a circular trajectory can do. Meanwhile, the x-ray generator unit 11 may include a plurality of x-ray source units fixedly arranged at a plurality of positions on a circular locus. In this case, the plurality of X-ray source units may be an X-ray tube of a miniaturized field emission system, and may include an electric driving system for controlling them in conjunction with the position of the X-ray detector unit 12. The X-ray detector 12 can be configured to move along a circular trajectory (see arrow a12) by a mechanical driving system. The X-ray detector 12 may also include a fixed detector array having a plurality of detector units arranged along a circular trajectory. In this case, the X-ray detector unit 12 may be partially driven so that only a part of the detector units facing the X-ray emission focus among the plurality of detector units constituting the fixed detector array receive the X-ray.

The subject bed 20 can move along the longitudinal direction of the subject, that is, the longitudinal direction of the subject, along the axial direction of the gantry housing (see arrow a20) during x-ray imaging. The X-ray image photographing apparatus according to the present invention can be used in combination with a computer tomographic image, that is, rotation of an X-ray beam X with respect to a subject during CT imaging (hereinafter referred to as virtual rotation due to sequential movement of X- So that the object bed 20 is moved.

On the other hand, when the surface perpendicular to the longitudinal axis of the subject is referred to as a cross section, the X-ray generator section 11 and the X-ray detector section 12 irradiate the X-ray beam X at mutually opposing positions on different cross- And receives it. In other words, the x-ray generator portion 11 and the x-ray detector portion 12 are present on different planes perpendicular to the longitudinal axis of the subject, and the center line of the x-ray beam X is located between the two planes And does not perpendicular to the longitudinal axis of the subject but proceeds in an inclined manner.

FIG. 2 schematically shows a cross section and a longitudinal section of an X-ray imaging apparatus according to an embodiment of the present invention. FIG. 3 shows the trajectory of the X-ray source and the trajectory of the X-ray detector when photographing the X-ray in the embodiment of FIG.

The photographing unit 201 of the X-ray image photographing apparatus according to the present embodiment includes a sample body 20 configured to be movable in the longitudinal direction of the subject, as in the embodiment of FIG. 1 described above, Ray generator portion 111 and an X-ray detector portion 120 in the gantry housing. The gantry housing has a cylindrical shape with an empty center, and the x-ray detector portion 120 is configured such that the locus of the x-ray emitting focus and the locus of the x-ray receiving portion overlap with each other when viewed from the side of the gantry housing Are placed on different planes.

The x-ray generator unit 111 includes a plurality of x-ray source units 111a, 111b and 111c fixedly arranged along a circular first trajectory 111L on a first plane Ps perpendicular to the longitudinal axis of the inspected object, . The plurality of X-ray source units 111a, 111b and 111c are arranged to irradiate the X-ray beam XT1 toward the inspected object on the test bed 20. [ On the other hand, the X-ray detector unit 120 is disposed at a position where the X-ray beam XT1 can be received with the inspected object therebetween so that its light-receiving surface faces the X-ray emission focus. Although not shown here, the x-ray detector portion 120 is mechanically aligned along a second circular path 120L, which is perpendicular to the longitudinal axis of the subject and on a second plane Pd that is different from the first plane And may be configured to be rotationally driven.

The X-ray generator unit 111 is connected to a plurality of X-ray source units (not shown) in cooperation with the mechanical rotation (see arrow a120) of the X-ray detector unit 120 to irradiate the X- The units 111a, 111b, and 111c can be electrically sequentially driven. The X-ray beam XT1 is irradiated with rotation (refer to arrow aXT1) with respect to the inspected object.

Here, the X-ray beam XT1 advances obliquely at a predetermined angle with respect to the first and second planes Ps and Pd, as shown in the right vertical section of FIG. To this end, the X-ray generator portion 111 is arranged such that its X-ray emission direction is inclined by an angle As with respect to the first plane to which the rotation locus belongs, and the X-ray detector portion 120, And is inclined by an angle Ad with respect to the face of the shape. That is, the light receiving surface of the X-ray detector unit 120 is disposed perpendicular to the center line of the X-ray beam XT4. Here, the angle As and the angle Ad may have the same value.

Next, with reference to FIG. 2, advantages according to the configuration of the present invention will be described. 2, the x-ray generator portion 111 appears to be arranged along a locus having a smaller radius than the x-ray detector portion 120, but this is only for the purpose of expressing the respective components so as to be seen clearly in the drawing. Actually they can be placed along a trajectory with similar radii as shown in the right longitudinal section of FIG. Even if the radius Rs of the first locus 111L and the radius Rd of the second locus 120L are the same, the two loci exist on the different planes Ps and Pd, The unit 111 and the X-ray detector unit 120 do not interfere with each other. Even if the X-ray generator portion 111 or the X-ray detector portion 120 is constituted by a plurality of units fixedly arranged along the loci 111L and 120L, the structure is not obstructed at all in the progress of the X-ray beam XT1 It does not.

As a result, the X-ray imaging apparatus according to the present invention can reduce the size of the outer radius Rg of the gantry housing. In addition, it is possible to reduce the gap G between the outer diameter and the inner diameter of the gantry housing, thereby securing a sufficient space for the subject body 20 and the subject to be placed. This is because the locus of the X-ray generator and the X-ray detector need not exist on the same plane.

3, the first plane Ps and the second plane Pd are parallel to each other, and the first locus 111L and the second locus 120L may be circular, respectively. In this case, when the X-ray beam direction is rotated and X-ray imaging data of a plurality of frames are obtained in various directions, there is an advantage that the magnification for the subject is kept constant. However, the present invention is not limited thereto. The first plane (Ps) and the second plane (Pd) may be different planes or may not be parallel to each other. In addition, the first locus 111L and the second locus 120L may be closed loop types, but may not be circular. For example, an elliptical shape or a polygonal shape. However, when the first and second trajectories are not circular shapes that are parallel to each other, the azimuth angle and magnification degree information of the x-ray beam are stored together for each frame at the time of x-ray photographing, .

4 schematically shows a cross-sectional view of an x-ray imaging apparatus according to an embodiment of the present invention.

In the X-ray imaging apparatus according to the present embodiment, the photographing unit 202 is substantially the same as the photographing unit 201 according to the embodiment of FIG. 2, but is composed of a plurality of detector units whose X- And a rotary detector array 13 is provided. The plurality of detector units may be arranged in a single line in an arcuate shape, or may be arranged in multiple lines.

The rotation detector array 13 detects the X-ray beam XT2 traveling from the X-ray emission focus through the longitudinal axis of the subject according to the movement of the X-ray emission focus according to the driving of the X- (See arrow a13) and receives the X-rays transmitted through the object. In this case, the rotary detector array 13 can be mechanically rotated and driven in conjunction with the rotation of the X-ray beam XT2 (refer to arrow aXT2) according to the electric driving of the X-ray generator 111. [

5 schematically shows a cross-sectional view of an x-ray imaging apparatus according to an embodiment of the present invention.

In the X-ray imaging apparatus according to the present embodiment, the photographing unit 203 includes a fixed detector array 14 composed of a plurality of detector units 141, which are circularly fixedly arranged along a circular second locus. 2 and Fig. 4, respectively. The fixed detector array 14 is disposed at the position of the emission focus of the X-ray beam XT3 irradiated toward the inspected object according to the position of the X-ray source unit 111a selectively driven by the X-ray generator unit 111 The region opposed thereto is activated to generate X-ray receiving data for each region.

When the X-ray beam XT3 is rotated (see an arrow aXT3), the region of the fixed detector array 14 opposed to the X-ray beam XT3 is sequentially activated to generate X-ray receiving data. However, the X-ray beam and the activation region do not necessarily have to be driven to rotate sequentially. It is sufficient that information on the azimuth angle of the irradiated x-ray beam per unit of the x-ray receiving data, that is, information on which x-ray beam emitted from an x-ray source unit is data, is sufficient. It is also possible to acquire light reception data by activating several X-ray source units and corresponding areas simultaneously.

FIG. 6 schematically shows a longitudinal section of an X-ray imaging apparatus according to an embodiment of the present invention.

As shown in the drawing, the photographing unit 204 of the X-ray imaging apparatus according to an embodiment of the present invention may include two housings 204S and 204D separated from each other. For example, in one housing 204S, an x-ray generator portion 111 composed of a plurality of x-ray source units arranged along a circular trajectory on a first plane Ps is accommodated, and the other one of the housings 204D is accommodated in a second plane Ray detector unit 120 having the above-described fixed detector array (see FIG. 5) or the rotary detector array (see FIG. 4) arranged or moved along a circular locus on the substrate Pd.

These two housings 204S and 204D move relative to each other in the longitudinal direction of the subject (see an arrow a204), and the distance between them can be changed. In this case, the angle As between the center line of the X-ray beam XT4 emitted from the X-ray generator portion 111 and the first plane Ps and the angle of the light receiving surface of the X-ray detector portion 120 with respect to the cylindrical plane of the locus (Refer to arrows a111 and a120). The light receiving surface of the X-ray detector unit 120 is preferably perpendicular to the center line of the X-ray beam XT4, but is not limited thereto.

10: Gantry housing
11, 111: X-ray generator section 12, 120: X-ray detector section
13: Rotation detector array 14: Fixed detector array
20: object bed 111a to 111d: X-ray source unit
141: Detector unit 201 to 204:

Claims (6)

Ray generator portion where the position of the x-ray emission focus rotates along a first locus on a first plane perpendicular to the longitudinal axis of the subject and emits an x-ray beam; And
An X-ray detector for receiving the X-ray beam at a light receiving position opposite to the X-ray emitting focus with the longitudinal axis of the inspected object in a second locus on a second plane different from the first plane; / RTI >
X-ray imaging device. The method according to claim 1,
Wherein the first plane and the second plane are parallel to each other,
Wherein each of the first trajectory and the second trajectory is a closed loop type trajectory centering on a longitudinal axis of the subject,
X-ray imaging device. The method according to claim 1,
Wherein the light receiving surface of the x-ray detector portion is perpendicular to the center line of the x-
X-ray imaging device. The method according to claim 1,
The X-
And a plurality of X-ray source units fixedly mounted on the first locus and driven in conjunction with a position for receiving X-rays at the X-ray detector unit,
X-ray imaging device. The method according to claim 1,
The X-
A rotary detector array having at least two detector units and being rotationally driven along the second locus,
X-ray imaging device. The method according to claim 1,
The X-
And a fixed detector array including a plurality of detector units fixedly disposed along the second locus, wherein the detector unit selectively drives a corresponding one of the plurality of detector units according to a position of the X-
X-ray imaging device.

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