JPH0570507U - X-ray CT - Google Patents

Abstract

(57) [Summary] [Purpose] To realize an X-ray CT capable of taking a large opening in the subject housing. [Arrangement] An arcuate or arcuate aperture 8 having a slit 5 in the middle of a curved plate 7 is arranged between a bowtie filter 2 and an opening 4 of a subject housing portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an X-ray CT capable of taking a large opening in a subject containing portion for containing a subject.

[0002]

[Prior Art]

 In X-ray CT, a bow-tie filter is used to reduce exposure to the body surface of the subject, and an aperture is placed in front of the bow-tie filter, that is, on the side close to the subject to determine the slice thickness for tomography. This layout is shown in FIG. In the figure, 1 is an X-ray focal point for irradiating X-rays, and 2 is a bow-tie filter provided to reduce exposure to the surface of the subject. Reference numeral 3 is an aperture that determines the slice thickness of the subject. The aperture 3 has a flat plate shape in order to simplify the structure. Reference numeral 4 denotes an opening of a subject storage portion that stores the subject. An example of the structure of the aperture 3 is shown in FIG. (A) is an example in which a slit 5 is formed on a lead flat plate 6, and (b) is an example in which two lead flat plates 6 are arranged so as to provide the slits 5 shown in the figure.

[0003]

[Problems to be solved by the device]

 By the way, since the aperture 3 has a flat plate shape as described above, the opening 4 of the subject housing portion cannot be fitted into the recess of the bowtie filter 2, and the size of the opening 4 of the subject housing portion is limited. ..

The present invention has been made in view of the above points, and an object of the present invention is to realize an X-ray CT capable of taking a large opening in the subject housing portion.

[0005]

[Means for Solving the Problems]

 The present invention, which solves the above-mentioned problems, places a bow-tie filter in front of an X-ray focal point for irradiating X-rays to reduce surface exposure, and a tomographic image is formed between the bow-tie filter and the opening of the subject housing part. In the X-ray CT in which an aperture for determining the slice thickness is arranged, the aperture is characterized in that a slit is provided in the middle of a curved plate curved in an arc shape or an arc shape.

[0006]

[Action]

 Since the structure of the aperture is arcuate, the subject opening can be fitted into the concave portion of the bow-tie filter at the time of arrangement, and the subject containing portion opening can be enlarged.

[0007]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a structural diagram of an aperture used in an X-ray CT according to an embodiment of the present invention. In the figure, the same parts as those in FIG. 4 are designated by the same reference numerals. In the figure, 7 is a curved plate formed by bending the flat plate 6 of the conventional aperture 3 shown in FIG. 4 into an arc shape, and 8 is an aperture formed by arranging two curved plates so as to form the slit 5.

FIG. 1 shows an X-ray irradiation unit of an X-ray CT according to an embodiment of the present invention using the aperture 8 shown in FIG. In the figure, the same parts as those in FIGS. 3 and 2 are designated by the same reference numerals. The figure shows a state in which an arcuate aperture 8 is arranged in front of the bow-tie filter 2 so as to be fitted into the recess of the bow-tie filter 2, and the subject accommodation portion opening 4 is provided along the aperture 8.

Next, the operation of the embodiment configured as described above will be described. X-rays are emitted from the X-ray focal point 1, pass through the bow-tie filter 2, and the irradiation width is limited by the aperture 8 to determine the slice thickness, and the X-rays are emitted to the subject stored in the subject storage opening 4. To be done. Since the aperture 8 is curved as shown in the figure, the subject accommodation portion opening 4 can be slightly fitted into the concave portion of the bow-tie filter 2, and the subject accommodation portion opening 4 can be enlarged. For example, in the embodiment of FIG. 1, the diameter is 1.2 times as large as that in the case of FIG. Therefore, a large subject can be accommodated.

The present invention is not limited to the above embodiment. For example, although the curved plate has a bow shape, it may have a circular arc concentric with the opening of the subject storage portion.

[0012]

[Effect of the device]

 As described above in detail, according to the present invention, it is possible to make the opening of the subject accommodation portion large, and the practical effect is great.

[Brief description of drawings]

FIG. 1 is a layout view of an X-ray irradiator according to an embodiment of the present invention.

FIG. 2 is a structural diagram of an aperture used in the X-ray irradiation unit of the present invention.

FIG. 3 is a layout view of an X-ray irradiation unit of a conventional X-ray CT.

FIG. 4 is a structural diagram of a conventional aperture.

Claims (1)

[Scope of utility model registration request] 1. A bow-tie filter (2) is placed in front of an X-ray focal point for irradiating X-rays to reduce surface exposure, and a slice is provided between the bow-tie filter (2) and the subject-accommodation-portion opening (4). In an X-ray CT in which an aperture (8) for determining the slice thickness of an image is arranged, the aperture (8) is provided with a slit (5) in the middle of a curved plate (7) curved in an arc shape or an arc shape. X-ray CT characterized by being a thing.