JPH05200022A - Radiation image recording and reading apparatus - Google Patents

Abstract

PURPOSE:To enable the continuous recording and reading of images, efficient instant acquisition of multilayer tomogram image and the repetitive use of a record body by providing an image recording and reading unit including a camera section, image reading section and erasing section in radiation image recording and reading apparatus. CONSTITUTION:An radiation image recording and reading apparatus is provided with an image recording and reading unit 10 and a means for relatively moving the unit 10 and a radiation source about a tomographic plane of a subject to satisfy the linear law and geometrical law. The image recording and reading unit 10 is provided with an image reading section having a belt-like record body 11, a transfer means thereof, an exciting light source 15 for emitting exciting light 16 to scan the record body 11 having a radiation image of the subject accumulatively recorded therein and a photoelectric reading means 14 to read stimulated light emitted from the record body 11 scanned by the exciting light 16 for obtaining an image signal and an erasing section 18 to irradiate the record body 11 with erasing light and radiate the remaining radiation energy of the record body 11 before the image is recorded by the image reading section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention accumulates and records a radiation image on a stimulable phosphor sheet, irradiates it with excitation light, and detects the light that stimulates and emits light according to the image recorded and accumulated. More specifically, the present invention relates to a radiation image recording / reading apparatus that performs simultaneous multilayer tomography.

[0002]

2. Description of the Related Art Radiation (X-ray, α-ray,
When irradiated with β rays, γ rays, electron rays, ultraviolet rays, etc., a part of the energy of this radiation is accumulated in the phosphor, and when the phosphor is irradiated with excitation light such as visible light, it is accumulated. The phosphor emits stimulated emission depending on energy. A phosphor having such a property is called a storage phosphor.

Using this stimulable phosphor, radiation image information of a subject such as a human body is once recorded on a stimulable phosphor sheet (hereinafter referred to as "accumulative phosphor sheet" or simply "sheet"). , Radiation image information for scanning this with excitation light to cause stimulated emission, photoelectrically reading this stimulated emission to obtain an image signal, and processing this image signal to obtain a radiation image of a subject with good diagnostic suitability. A recording / reproducing method has been proposed (for example, JP-A-55-12429, JP-A-55-116340, and JP-A-55-116340).
55-163472, 56-11395, 56-104645, etc.).

In this method, the final image can be reproduced as a hard copy or on a CRT. In any case, in such a radiation image information recording / reproducing method, the stimulable phosphor sheet does not finally record image information, but is temporarily used to give an image to the final recording medium as described above. Since it carries image information, this stimulable phosphor sheet may be used repeatedly, and if it is used repeatedly like this, it is extremely economical.

In order to reuse the stimulable phosphor sheet as described above, the radiation energy remaining in the stimulable phosphor sheet after the stimulated emission light is read is determined by, for example, Japanese Patent Laid-Open No. Sho 56-56.
No. 11392, No. 56-12599, the sheet is irradiated with light or heat to be emitted to erase the residual radiation image, and the stimulable phosphor sheet may be used again for recording a radiation image. ..

[0006] Therefore, the applicant of the present invention circulates a stimulable phosphor sheet capable of accumulating and recording a radiation image along a predetermined circulation passage, and a circulation conveyance means, and in the circulation passage, the sheet is irradiated with radiation through a subject. By irradiating, an image recording unit that accumulates and records the radiation image information of the subject on this sheet, and excitation light that scans the sheet in the circulation passage where the radiation image information is accumulated and recorded in the image recording unit. An image reading section that is composed of an excitation light source that emits light and a photoelectric reading unit that obtains an image signal by reading stimulated emission light emitted from a sheet that is scanned by the excitation light; and an image in the image reading section that is in the circulation passage. An erasing unit that releases the radiation energy remaining on the sheet before the image is recorded on the sheet after the reading is performed. A so-called built-in type radiographic image information recording / reading device in which the above-mentioned stimulable phosphor sheet was circulated between the above-mentioned parts and repeatedly used was proposed in the apparatus (Japanese Patent Application No. 58-66730). ). According to the radiation image information recording / reading device having such a structure,
Radiation image information can be recorded and read continuously and efficiently. Therefore, this radiation image information recording / reading device is particularly suitable for mass examinations, and for the purpose of mass examinations, etc. It is also possible to load on such a mobile station.

By the way, one of the photographing methods for accumulating and recording the radiation image information of the subject on the sheet by irradiating the stimulable phosphor sheet with radiation through the subject is a so-called tomography method. (See, for example, JP-A-58-67245).

[0008] Such a tomography method is a method in which a radiation source, for example, an X-ray source and a stimulable phosphor sheet are arranged through a subject, and the X-ray source and the sheet are placed at the time of X-ray irradiation. A straight line rule (center of X-ray source, one point on the fault plane and one point on the above sheet form a straight line)
And the constant law (the ratio between the distance a between the focal plane and the fault plane and the distance b between the fault plane and the sheet is constant) is relatively moved to obtain the desired fault on the sheet. Only the plane is imaged and the tomographic planes of other subjects are blurred. As a result, X of only the desired tomographic plane of the subject is obtained.
A line image can be obtained.

Further, the present inventor has proposed a simultaneous multi-layer tomography apparatus as an apparatus capable of obtaining a plurality of cross-sectional layers of a subject at one time (simultaneously) by stacking a plurality of stimulable phosphor sheets and performing the same photographing as described above. (See JP-A-58-67245).

In the above-mentioned tomography method or apparatus,
It suffices if the above-mentioned straight line law and the geometrical law are substantially established. Therefore, various methods such as a linear orbit, a circular orbit, an elliptical orbit, a hypocycloid orbit, and a spiral orbit method can be used as a method for moving the radiation source and the sheet. Can be used.

The simultaneous multilayer tomography apparatus will be described below with reference to the accompanying drawings. FIG. 3 shows an example in which horizontal linear motion is adopted as a method of moving the radiation source and the stimulable phosphor sheet.

X-ray source 21 and stimulable phosphor sheet 22a,
A cassette 23 containing a laminated body formed by laminating three sheets 22b and 22c is arranged via an X-ray subject 24.

At the time of photographing, the X-ray source 21 and the cassette 2
X-rays are emitted from the X-ray source 21 while transferring 3 in the directions of arrows 25 and 26, respectively. Then, for example, the tomographic plane of the subject 24 imaged on the stimulable phosphor sheet 22a is X
X-rays 27a, 27a 'emitted from the radiation source 21 are intersections 28a formed along with the transfer of the X-ray source 21,
X-rays 27c and 27c 'radiated from the X-ray source 21 are applied to the tomographic plane of the subject 24 formed on the stimulable phosphor sheet 22c.
Crossing portion 28c formed by the transfer of the X-ray source 21
Is.

With this simultaneous multi-layer tomography apparatus, images of a plurality of tomographic planes of a subject can be obtained by a single image taking, and therefore, for a moving organ such as the heart or lung, a tomographic image having the same movement phase is obtained. It is possible to obtain images of a plurality of tomographic planes in which there is no movement of the subject, which is usually unavoidable between each tomographic image, in other regions as well, and further reduction of exposure dose,
The physical and mental burden on the subject is also reduced, which is convenient for diagnosis.

[0015]

However, in this cassette for simultaneous multi-layer tomography, in order to accommodate a plurality of stimulable phosphor sheets at a predetermined interval, styrofoam is placed between these stimulable phosphor sheets. Since the slice interval is determined by arranging the spacers made from etc., it not only takes time to set the stimulable phosphor sheet in the cassette, but also when reading these stimulable phosphor sheets, It is necessary to perform a labor-consuming and time-consuming operation of taking out the cassette accommodating the fluorescent phosphor sheet from the photographing device, further taking out the accumulative phosphor sheet from the cassette, and then reading.

Further, in order to change the slice interval, a spacer and a cassette corresponding to the interval are newly required, so that the desired interval cannot be easily set.

Therefore, in view of the above circumstances, it is an object of the present invention to provide a radiation image recording / reading apparatus capable of obtaining a multilayer tomographic image by one operation and easily setting a desired slice interval. ..

[0018]

A radiation image recording / reading apparatus according to the present invention comprises a radiation source, an image recording / reading unit arranged on the opposite side of the radiation source with respect to the radiation source, and
The image recording / reading unit and means for relatively moving the radiation source about the tomographic plane on which the subject is located so as to satisfy the straight line constant and the geometrical ratio rule, A belt-shaped recording body in which a stimulable phosphor layer is laminated on a support, and the belt-shaped recording body is conveyed along a predetermined path facing the radiation source and including a plurality of parallel imaging positions. Transporting means, an excitation light source that emits excitation light that scans a belt-shaped recording medium on which a radiation image of the subject is accumulated and recorded by the radiation that is generated from the radiation source and that has passed through the subject, and the excitation light is scanned. An image reading unit having a photoelectric reading unit that obtains an image signal by reading the stimulated emission light emitted from the belt-shaped recording medium, and after the image reading is performed in the image reading unit. Before the image is recorded on the belt-shaped recording medium, the belt-shaped recording medium is provided with an erasing section for irradiating the belt-shaped recording medium with erasing light to radiate the residual radiation energy of the belt-shaped recording medium. To do.

This image recording / reading unit is capable of continuously and efficiently recording and reading radiation image information as in the built-in type radiation image recording / reading apparatus described above. In the previous radiation image recording / reading apparatus, radiation image information is stored and recorded in each separate stimulable phosphor sheet, whereas in this unit, radiation image information of a plurality of cross-sectional layers is stored one at a time. The radiation image recording / reading device is different from the previous radiation image recording / reading device in that it is recorded at a plurality of photographing positions of the fluorescent substance.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 is a schematic view showing an embodiment of the radiation image recording / reading apparatus of the present invention.

In FIG. 1, an X-ray source 1 and an image recording / reading unit 10 facing the X-ray source 1 and including parallel photographing positions 3a, 3b, 3c are arranged on the opposite side of a subject 2. Has been done.

FIG. 2 is a schematic view showing an embodiment of an image recording / reading unit included in the radiation image recording / reading apparatus of the present invention.

In FIG. 2, both ends of a belt-shaped recording medium (hereinafter referred to as a recording medium) 11 in which a stimulable phosphor layer is laminated on a long belt-shaped support are respectively rewinding and rewinding rollers 12. The recording medium 11 is wound around the recording medium 11 by a plurality of guide rollers 13 provided on the path of the recording medium 11.
Is configured to pass through the photographing positions 3a, 3b, 3c. Beside and below the photographing positions 3a, 3b, 3c, the portions of the recording body 11 where the photographing is not performed (the portions before and after the photographing) do not accumulate the X-rays emitted from the X-ray source 1. Lead plate 1 for shielding the X-ray
9 are arranged. An image reading unit and an erasing unit 18 are arranged on the passage at one end of the recording body 11. This image reading unit reads an excitation light source 15 that emits excitation light 16 such as a laser beam that scans the recording body 11 and a photostimulable emission light emitted from the recording body 11 by this excitation light scanning to obtain an electric image signal. It is composed of photoelectric reading means 14 such as Maru. On the optical path of the excitation light 16, a galvano mirror 17 that polarizes the excitation light in the main scanning direction is arranged. The erasing unit 18 is provided with a large number of erasing light sources 18a such as a fluorescent lamp, a tungsten lamp, a sodium lamp, and a xenon lamp.

Next, the photographing process will be described with reference to FIGS.

At the time of photographing, the X-ray source 1 and the image recording / reading unit 10 are moved in the directions of arrows 4 and 5 respectively by means of relative movement (not shown), and the X-ray source 1 and the X-ray source are moved.
Irradiate the subject 2 with a line. As a result, as in the case of FIG. 3 described above, the tomographic image of the tomographic plane 7a of the subject 2 is taken at the photographing position 3a.
X-ray energy is accumulated and recorded in the recording body 11 of the tomographic image, and the tomographic images of the tomographic planes 7b and 7c are captured at the imaging positions 3b and 3c, respectively.
It is stored and recorded in the recording body 11 of.

When the photographing is completed in this way, the winding / rewinding roller 12 on the reading unit side of the recording body 11 starts winding the recording body 11. When the recording body 11 (the recording body arranged at the photographing positions 3a, 3b, 3c at the time of photographing) of the portion where the photographing is performed reaches the reading unit, the excitation light source 15 irradiates the recording body 11 with the excitation light 16. This recording body 11 emits stimulated emission light. The emitted light is read by the photoelectric reading unit 14 to obtain an electric image signal. Here,
Due to the positional relationship shown in FIG. 2, the image signals obtained at the photographing positions 3a and 3c are both photographed from the front side of the recording body 11, but the image signal obtained at the photographing position 3b is the same as that of the recording body 11. Each image processing is performed on these image signals, keeping in mind that the images were taken from the back side.

After this reading, the recording medium 11 is further conveyed to the erasing section 18 by the take-up / rewinding roller 12, and the erasing light emitted from the erasing light source 18a reduces the X-ray energy remaining on the recording medium 11. Erased. When all the X-ray energy is erased, the reproduction of the recording body 11 is completed, and one of the take-up / rewinding rollers 12 becomes the recording body 11.
Is rewound to the original position and the preparation for the next shooting is completed.

In the radiation image recording / reading apparatus of the above-described embodiment, the relative movement of the X-ray source 1 and the image recording / reading unit 10 was linearly performed in the horizontal direction. As long as it is satisfied, therefore, as a moving method for the X-ray source 1 and the image recording / reading unit 10, various methods such as a circular orbit, an elliptical orbit, a hypocycloidal orbit, and a spiral orbit method are used in addition to the linear orbit. obtain.

Further, as shown in FIG. 4, the belt-shaped recording material 1
It is also possible to use an endless recording medium instead of a long recording medium 1 '. In this case, by providing the feed roller 12 'in place of the two take-up / rewind rollers 12 in the image recording / reading unit 10', the recording body 11 'can be read and erased. That is, in the above-described embodiment, the recording medium 11 is read while being wound by one of the take-up and rewind rollers 12 and erased, and after the end, it is rewound by the other take-up and rewind roller 12 to prepare for the next photographing. However, the image recording / reading unit 10 'performs reading and erasing while conveying the recording medium 11' by the feed roller 12 ', and after that, the recording medium 11' is also conveyed in the same direction so that the next photographing is performed. Can be prepared.

Next, a further different embodiment of the radiographic image recording / reading apparatus of the present invention will be described with reference to FIG. 5 so that the slice intervals for multilayer tomography can be easily set.

FIG. 5 is a partial schematic view of the image recording / reading unit 30. The image recording / reading unit 30 is provided with guides 31a, 31c for setting the recording body 11 up and down above or below the photographing positions 3a, 3c of the image recording / reading unit 10, respectively. Here, the guides 31a and 31c are vertically movable. To increase the slice interval, the guide 31a may be moved upward and at the same time the guide 31c may be moved downward, and to reduce the slice interval, the guide 31a may be moved.
Should be moved downward and at the same time the guide 31c should be moved upward. Although an example using a guide is shown here, a movable guide roller may be provided, and the slice interval may be changed by moving the imaging position with this guide roller.

Although the radiation image recording / reading apparatus capable of obtaining three layers of tomographic images has been described in the above embodiments, the radiation image recording / reading apparatus of the present invention is an apparatus capable of obtaining a multilayer tomographic image. It is not limited to such three layers.

[0034]

Since the radiation image recording / reading apparatus of the present invention comprises an image recording / reading unit including a photographing position (imaging unit), an image reading unit, and an erasing unit, recording and reading of images are continuously performed. Therefore, a multilayer tomographic image can be efficiently and instantly obtained, and the recording medium can be repeatedly used by reproducing the recording medium.

Further, since a guide for setting the passage of the recording medium is provided so as to be movable while keeping the respective photographing positions parallel to each other, it is possible to easily set the slice interval of the slice of the object to a desired interval. ..

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating an embodiment of a radiation image recording / reading device of the present invention.

FIG. 2 is a schematic diagram illustrating an embodiment of an image recording / reading unit of the radiation image recording / reading apparatus of the present invention.

FIG. 3 is a schematic diagram illustrating a simultaneous multi-layer tomography apparatus.

FIG. 4 is a schematic view illustrating another embodiment of the image recording / reading unit of the radiation image recording / reading apparatus of the present invention.

FIG. 5 is a partial schematic view for explaining another embodiment of the image recording / reading unit of the radiation image recording / reading apparatus of the present invention.

[Explanation of symbols]

1, 21 X-ray source 2, 24 Subject 3a, 3b, 3c Imaging position 4,5, 25, 26 Relative movement direction 6a, 6c, 6a ', 6c' 27a, 27c, 27
a ', 27c' X-ray 7a, 7c, 28a, 28c Tomographic plane 10, 10 ', 30 Image recording / reading unit 11, 11' Belt-shaped recording medium 12 Winding / rewinding roller 12 'Feed roller 13 Guide roller 14 Photoelectric reading Means 15 Excitation Light Source 16 Excitation Light 17 Galvano Mirror 18 Erasing Section 18a Erasing Light Source 19 Copper Plates 22a, 22b, 22c Storage Phosphor Sheet 23 Cassettes 31a, 31c Guide

Claims (4)

[Claims] 1. A radiation source, an image recording / reading unit arranged on the opposite side of the radiation source with respect to the object, and the image recording / reading unit and the radiation source centered on a tomographic plane on which the object is located. The image recording / reading unit comprises a belt-shaped recording medium in which a stimulable phosphor layer is laminated on a belt-shaped support. Transporting means for transporting the belt-shaped recording body along a predetermined path including a plurality of imaging positions which are parallel to and face the radiation source, the radiation generated by the radiation source and transmitted through the subject. An excitation light source that emits an excitation light that scans a belt-shaped recording material on which a radiation image of a subject is stored and recorded, and a stimulated emission light emitted from the belt-shaped recording material that is scanned by the excitation light are read. An image reading unit having a photoelectric reading unit for obtaining an image signal, and before the image is recorded on the belt-shaped recording medium after the image is read by the image reading unit, the belt-shaped recording medium is recorded on the belt-shaped recording medium. A radiation image recording / reading apparatus, comprising: an erasing unit that irradiates erasing light to radiate residual radiation energy of the belt-shaped recording body. 2. The belt-shaped recording medium is an endless belt-shaped recording medium, and the conveying means conveys the belt-shaped recording medium by a feed roller that suspends the endless belt-shaped recording medium. Claim 1 characterized by the above.
The radiation image recording / reading device described. 3. The belt-shaped recording medium is a long belt-shaped recording medium, and the conveying means is a belt-shaped recording medium by a take-up / rewinding roller wound at both ends of the long belt-shaped recording medium. 2. The present invention is characterized in that it conveys
The radiation image recording / reading device described. 4. A means for moving the belt-shaped recording medium at a plurality of predetermined photographing positions parallel to each other on the belt-shaped recording medium so as to change intervals between the plurality of predetermined photographing positions. The radiation image recording / reading device according to claim 1, wherein