JPH012033A - Radiation image information recording/reading device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of the Invention) The present invention involves accumulating and recording radiation image information on a stimulable phosphor, then irradiating it with excitation light, and producing stimulated luminescence according to the accumulated and recorded image information. The present invention relates to a radiation image information recording/reading device that detects light to read image information and converts it into an electrical signal, and particularly relates to a radiation image information recording/reading device that can simultaneously record and read image information.

(Conventional technology) Certain types of phosphors are exposed to radiation (X-rays, α-rays, β-rays.

When irradiated with γ-rays, electron beams, ultraviolet rays, etc., a part of this radiation energy is accumulated in the phosphor, and when this phosphor is irradiated with excitation light such as visible light, the phosphor changes depending on the accumulated energy. is known to exhibit stimulated luminescence, and phosphors exhibiting this property are called stimulable phosphors (stimulable phosphors).

Using this stimulable phosphor, radiation image information of a subject such as a human body is temporarily recorded on a recording medium having a stimulable phosphor layer, and this recording medium is scanned two-dimensionally with excitation light such as a laser beam. The resulting stimulated luminescent light is photoelectrically read by a photodetector to obtain an image signal, and based on this image signal, a recording material such as a photographic light-sensitive material, a display device such as a CRT, etc. The present applicant has already proposed a radiation image information recording and reproducing system that outputs a radiation image of a subject as a visible image. (Unexamined Japanese Patent Publication No. 12429/1983.

56-L13'15 etc. ) This system has the practical advantage of being able to record images over a much wider range of radiation exposure compared to conventional radiographic systems using silver halide photography. In other words, in a stimulable phosphor, it is recognized that the amount of emitted light that is stimulated to emit light due to excitation after accumulation is proportional to the amount of radiation exposure over an extremely wide range.
Therefore, even if the amount of radiation exposure varies considerably due to various imaging conditions, the amount of stimulated luminescence emitted from the recording medium containing the stimulable phosphor can be read by setting the gain to an appropriate value and adjusting the photoelectric conversion means. is read and converted into an electrical signal, and this electrical signal is used to record materials such as photographic light-sensitive materials, CRT
By outputting a radiation image as a visible image on a display device such as the above, it is possible to obtain a radiation image that is not affected by fluctuations in radiation exposure amount.

In the radiation image information recording and reproducing system described above, the recording medium containing the stimulable phosphor does not ultimately record image information, but temporarily stores image information in order to provide an image to the final recording medium as described above. Since it is supported, this recording medium may be used repeatedly, and such repeated use is extremely economical.

Therefore, the present applicant has previously proposed a radiation image information recording/reading device that realizes efficient cyclical reuse of stimulable phosphors (for example, Japanese Patent Laid-Open No. 58-200269).

The above-mentioned apparatus comprises a support, a recording body consisting of a stimulable phosphor layer fixed on the support and capable of storing and recording a radiographic image, and a recording body that is formed by irradiating the recording body with radiation through a subject. an image recording section for accumulating and recording a radiographic image of a subject; an excitation light scanning means for scanning excitation light onto a recording body on which the radiographic image has been accumulated and recorded; an image reading section having a photoelectric reading means for reading stimulated luminescence light to obtain an image signal; and the recording medium on the support is read by repeatedly moving the support and the image reading section relative to each other. means for circulating the image relative to the image reading section; and a means for emitting residual radiation energy on the recording medium prior to recording an image on the recording medium after the image reading is performed in the image reading section. An erasing section is incorporated into one device, and the recording medium can be efficiently circulated and reused. If the recording medium is one in which a plurality of stimulable phosphor layers are formed on an endless support belt, this recording medium is suspended on a roller or the like and circulated, and the image recording section and the image reading section It is extremely convenient because it can pass through the section and erasing section sequentially. A specific example of such a device is shown in FIG. 4, for example.

In the illustrated apparatus, three stimulable phosphor plates 102 are fixed on an endless conveyor 101, and this conveyor 101 is suspended between two rollers 103 and 104. By the rotation of 104, it is circulated and transferred in the direction of the arrow in the figure. Around this conveyor 101, an image recording section 110, an image reading section 120, and an erasing section 130 are sequentially arranged along the conveyance direction of the conveyor 101.

The image recording unit 110 includes a radiation source 111 such as an X-ray source,
A transmitted radiation image of the subject 112 is stored and recorded on the stimulable phosphor plate 102 facing the radiation source 111 via the subject 112. The phosphor plate 102 on which image information has been stored and recorded is then sent to an image reading section 120.

The image reading unit 120 includes excitation light 12L such as a laser beam.
An excitation light source 121 that emits light A, and an optical deflector 1 such as a galvanometer mirror that scans the excitation light 121A emitted from the excitation light source 121 in the width direction of the conveyor 101.
22, and a photodetector 123 that reads stimulated luminescence light 125 emitted by the stimulable phosphor plate 102 excited by the excitation light 121A. This photodetector +23 is
For example, head-on type photomultiplier tubes, photoelectron amplification channel plates, etc.
The stimulated luminescence light 12 guided by the light transmission means 124
5 is photoelectrically detected. A phosphor plate 1 is provided in the image reading section 120.
When 02 is sent, the phosphor plate 102 or the excitation light 12
By moving the scanning system of 1A and the detection system of stimulated luminescence light in a direction perpendicular to the scanning direction of excitation light 121A, the phosphor plate 1
02, the entire surface thereof is irradiated with excitation light, and image information is read over the entire surface. The phosphor plate 102 that has been read is carried into an erasing section 130 having an erasing light source 131. This erasing light source 131 is connected to the stimulable phosphor plate 10.
2, the radiation energy remaining in the stimulable phosphor plate 102 is emitted by irradiating the phosphor plate with light included in the excitation wavelength range; A tungsten lamp, a halogen lamp, an infrared lamp, a laser light source, etc., as shown in , are used. The phosphor plate that has been erased in the erasing section 130 is returned to the image recording section 110 again.
However, during the movement, the cleaning roller 105
to remove fine dust, clumps, etc. from the surface.

(Problems to be Solved by the Invention) However, in the above-mentioned apparatus, when recording image information in the image recording section 110, it is necessary to stop the conveyor 101, and when performing reading in the image reading section 120, it is necessary to stop the conveyor 101. Since it is necessary to move the conveyor 101, it has been difficult to record and read images at the same time. Therefore, while the image reading section 120 is reading a certain phosphor plate, it is necessary to wait before taking a picture, and since the above-mentioned reading takes a relatively long time, many pictures are taken one after another. There is a problem in that it is not possible to efficiently take pictures when necessary.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a radiation image information recording/reading apparatus that can perform imaging even while reading image information.

(Means for Solving the Problems) The radiographic image information recording/reading device of the present invention includes a recording belt that is an endless belt having a stimulable phosphor layer, and a recording belt such that the recording belt forms two surfaces. a recording belt section consisting of a pair of roller sections that is suspended and transported by a recording belt, which is provided opposite to one surface of the recording belt, and by irradiating the stimulable phosphor layer of the recording belt with radiation through the subject; An image recording section for accumulating and recording a radiation image of the subject on the phosphor layer is provided opposite to the other surface of the recording belt, and emits excitation light onto the stimulable phosphor layer on which the radiation image is accumulated and recorded. an image reading section having an excitation light scanning means for scanning, and a photoelectric reading means for reading stimulated luminescence light emitted from the stimulable phosphor layer scanned by the excitation light to obtain an image signal; An erasing section that releases residual radiation energy on the stimulable phosphor layer prior to image recording on the stimulable phosphor layer after image reading, and the recording belt section are used to read image information. The present invention is characterized by comprising a moving means for moving one side of the recording belt at a speed equal to the transporting speed of the recording belt;

The recording belt may have a stimulable phosphor layer formed over its entire surface, or may have a stimulable phosphor layer formed only in necessary areas.

(Function) According to the above device, in the image reading section, the recording belt is transported by the roller section and the entire recording belt section is moved by the moving means to perform sub-scanning, and in the image recording section, the recording belt is moved by the roller section. The transfer by the recording belt section and the movement of the entire recording belt section by the moving means cancel each other out, so that the recording belt stops at an apparently fixed position. Therefore, by rotating the roller section and driving the moving means, photographing and reading can be performed simultaneously.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing an outline of a radiation image information recording/reading apparatus according to an embodiment of the present invention.

In this apparatus, the recording belt 1, which is an endless belt, has a stimulable phosphor layer formed on its surface only in the shaded areas in the figure, and these areas serve as stimulable phosphor parts IA and IB, respectively. ing. The recording belt 1 is suspended between a first roller section 4 and a second roller section 5, and these roller sections 4.about.5 form two mutually parallel surfaces, an upper surface and a lower surface. Further, the first roller portion 4 has a shaft 4a.
and the roller 4b, and the second roller part 5 has the shaft 5a and the roller 5.
b are integrated via one-way clutches, and the shafts 4a and 5a are connected by a connecting arm 7. The above-mentioned one-way clutches each have a shaft 4a,
When the shaft 5a rotates clockwise, the rollers 4b and 5b are rotated together with the shaft, and when the shaft 4a and 5a rotate counterclockwise, the rollers 4b and 5b are made free. In this apparatus, a recording belt section 8 is composed of a recording belt 1 and two roller sections 4 and 5.

The recording belt section 8 is movable in the left and right directions in the figure, and means for moving the recording belt section is provided by moving the shaft 4a along the shaft 4a.
The shaft 4a is driven by a remoter 41 comprising a motor 41 that rotates in two directions, and a guide member 42 that extends in the left-right direction and is formed with a groove 42a in which the shafts 4a and 5a engage.
, 4b move along the groove 42a.

A radiation source 11 such as an X-ray source is disposed at a position facing the upper surface of the recording belt 1, and the image recording unit 1
0 is configured. When photographing in this image recording section 10, the recording belt section 8 is placed at the right end position as shown in FIG. 1(a), and the recording belt of the two stimulable phosphor sections The stimulable phosphor portion IA on the upper surface is placed at a position facing the radiation source 11. Furthermore, radiation image information has already been stored and recorded in the stimulable phosphor portion IB on the lower surface side of the recording belt 1.

An image reading section 20 for reading radiation image information stored and recorded in the stimulable phosphor section is disposed at a position facing the lower surface of the recording belt 1. The image reading unit 20 includes a laser light source 2
an excitation light scanning means 24 that deflects the excitation light 22 emitted from the excitation light 22 by an optical deflector 23 such as a galvanometer mirror and scans it in a direction perpendicular to the plane of the paper of FIG. 1;
This device is equipped with a photoelectric reading means 25 consisting of a light guide 26 and a photomultiplier 27, which photoelectrically detects the stimulated luminescent light emitted from the stimulable phosphor portion by scanning the laser beam 22. When one stimulable phosphor section is in the image recording section 10, the left end of the other stimulable phosphor section is at the scanning position of the laser beam. This device is capable of simultaneously performing photographing in the image recording section 1O and reading in the image reading section 20.The operation of the device during the above-mentioned photographing and reading will be explained below.

When the inside of the device is in the state shown in FIG. 1(a), the motor 41 rotates the shaft 4a counterclockwise.
The shaft 5a also rotates in the counterclockwise direction together with the shaft 5a. Further, the right end portion of the stimulable phosphor portion IA is held and fixed by the holding means 9 so as to maintain its absolute position. Axis 4a, 4
When roller b rotates counterclockwise, the rollers 4b and 5b rotate freely due to the one-way clutch described above, so that the ends of the stimulable phosphor portion IA are fixed, so that the rollers 4b and 5b rotate clockwise. . Therefore, even if the entire recording belt section 8 moves to the left, the stimulable phosphor section IA maintains the position facing the radiation source 11 as shown in FIG. 1(a). Therefore, in the image recording section 10, the recording belt section 8
Regardless of the movement of the subject 12, the radiation source 11 can be operated to accumulate and record a transmitted radiation image of the subject 12 in the stimulable phosphor portion IA. On the other hand, on the lower surface of the recording belt 1, assuming that the moving speed of the entire recording belt section 8 in the left direction is Vl, this moving speed Vl and the roller 4b,
The recording belt moves to the left at a speed of 2vl, which is the sum of the transport speed V1 of the recording belt 1 due to the rotation of the recording belt 5b. Therefore, in the image reading section 20, the stimulable phosphor section IB is sub-scanned at a speed of 2v1. The laser beam 22 two-dimensionally scans the stimulable phosphor portion IB which is sub-scanned as described above, and from the scanning location of the stimulable phosphor portion IB to the stimulable phosphor portion IB. Stimulated luminescent light is generated in accordance with the accumulated and recorded image information, and this stimulated luminescent light is transmitted to the light guide 2.
6 and is detected by a photomultiplier 27, from which an image signal based on the stimulated luminescent light is obtained. In the figure, reference numeral 28 denotes a reflecting mirror that reflects the light emitted from the stimulated emitted light on the side opposite to the light guide 26 toward the incident surface of the light guide.

When the recording belt section 8 is moved by half the length of the stimulable phosphor section IB as shown in FIG. 1(b), the laser beam 22 scans the entire surface of the stimulable phosphor section IB. end. Furthermore, since reading image information in the image reading section 20 takes a relatively long time, the stimulable phosphor section IB
The photographing of the stimulable phosphor portion IA in the normal image recording section 10 is completed before the reading of the stimulable phosphor portion IA is completed. In this way, when the photographing of the stimulable phosphor section IA and the reading of the stimulable phosphor section IB are completed, the recording belt section 8 is returned to the right end position, and the stimulable phosphor section IA is returned to the reading start position. The recording belt is transported so that the stimulable phosphor parts IB are respectively arranged in the photographing part 10.

That is, the recording belt section 8 located at the position shown in FIG. 1(b) is moved to the right by the motor 41 rotating the shaft 4a clockwise. Also, prior to this, the clamping means 9 releases the recording belt 9 from clamping. In the above case, the two rollers 4b and 5b are the shaft 4a.
, 5a. When the recording belt section 8 is moved to the right end position in this manner, the recording belt section 8 is in the state shown in FIG. 1(C). In this state, the entire recording belt section 8 is at the right end position, but the stimulable phosphor sections IA and IB are not sufficiently transported by the rotation of the rollers 4b and 5b, so the motor 41 moves the shaft 4a further clockwise. Continuing to rotate in the circumferential direction, the shaft 5b contacts the side edge of the groove 42a and slips, and the rollers 4b, 5
b continues to rotate clockwise, moving the stimulable phosphor part IB to the position of the stimulable phosphor part IA in FIG. 1(a), and moving the stimulable phosphor part IA to the stimulable phosphor part IA in FIG. They are each transferred to the positions of the phosphor portions IB. Also, recording belt 1
An erasing section 30 having an erasing light source 31 is provided at the left side of the image reading section 20, facing the lower surface of the image reading section 20.
Immediately after returning to the state shown in C), the stimulable phosphor portion IB is turned on and transported to the left with erasing light. This erasing light is light in the excitation wavelength range of the stimulable phosphor layer of the stimulable phosphor parts IA and IB, and the radiation energy remaining in the stimulable phosphor part IB after image reading is removed from the roller 4b.
, 5b and is emitted from the stimulable phosphor section IB by being irradiated with the above light. Erasing section 30
The stimulable phosphor section IB that has been erased is transported into the image recording section 10 and is ready for new recording.

As described above, according to the apparatus of this embodiment, by transporting the endless belt-like recording belt while moving the entire recording belt section, the stimulable phosphor section is apparently stopped in the image recording section, and the image is read. Since the stimulable phosphor section can be sub-scanned in the section, reading and photographing can be performed at the same time. Therefore, it is possible to take pictures even while reading, and it is possible to take many pictures efficiently.

Note that the stimulable phosphor layer on the recording belt may be provided not only on a part of the recording belt but also on the entire surface as described above. Furthermore, each roller section includes two rollers 14A,
14B and 15A, 15B, etc.
It may also consist of a plurality of roller groups. Furthermore, in the embodiment described above, one motor serves both as a means for moving the entire recording belt section and as a means for transporting the recording belt, but the movement of the recording belt section and the transportation of the recording belt are controlled by mutually independent means. It's okay. In that case, the above-mentioned clamping means etc. are not necessary. Further, the arrangement and specific structure of each part arranged around the recording belt part are not limited to the above-mentioned embodiments; for example, the image reading part 2
A long photomultiplier extending in the main scanning direction may be arranged as a photoelectric reading means for detecting stimulated luminescence light (see Japanese Patent Application Laid-Open No. 82-16688, etc.). Using a long photomultiplier is effective in downsizing the entire device.

Further, the image reading section does not necessarily have to be fixed opposite to the recording belt section, but may move integrally with the recording belt section. The apparatus in which the image reading section moves will be described with reference to FIG. In Fig. 3, the same parts as those of the device shown in Fig. 1 are given the same numbers.
The explanation will be omitted.

In the illustrated apparatus, an image reading section 120 is housed in a casing 50 at a position facing the lower surface of the stimulable phosphor belt 1 . This housing 50 is integrated with the connecting arm 7 by a support arm 50a, and the image reading section 12G inside the housing 50 is movable together with the stimulable phosphor belt section 8. The recording belt section 8 moves from the scanning start position shown in FIG. 3(a) to the position shown in FIG. 3(b) to read the stimulable phosphor section IB. , 5a, the transport speed of the recording belt section 8 due to the rotation of the recording belt section 8 is v2, the stimulable phosphor section IB moves to the left at a speed of 2v2, but the image reading section 120 also moves to the left together with the recording belt 8. Since the stimulable phosphor portion IB moves at a speed vl in the direction shown in FIG. Therefore, the distance that the recording belt section 8 moves until the reading is completed is equal to the length of the stimulable phosphor section IB.

As shown in FIG. 3(b), when the reading of the stimulable phosphor part IB is completed, the erasing part 130 provided in the housing 50
The erasing light source 131 is turned on, and the shafts 4a and 5a rotate clockwise to move the recording belt section 8 and the housing 50 to the right.

The shafts 4a and 5a have a recording belt section 8 shown in FIG. 3(C).
After being returned to the right end position as shown in FIG.
0 and is moved to the position of the stimulable phosphor portion IA in FIG. 3(a). Note that in such an apparatus in which the recording belt section and the image reading section move integrally, the two surfaces formed by the stimulable phosphor belt 1 may not necessarily be parallel.

(Effects of the Invention) As described in detail above, according to the radiation image information recording/reading apparatus of the present invention, in an apparatus using an endless belt-like recording belt, the recording belt is By moving the roller unit and the roller unit as one, it is possible to apparently stop the recording belt at the image reading unit while transporting the recording belt at the image reading unit. Therefore, it is possible to take pictures even while the image is being read, and a large number of pictures can be taken efficiently.

[Brief explanation of the drawing]

FIGS. 1(a), (b), and (c) are side views showing an outline of a radiation image information recording/reading device according to one embodiment of the present invention, and FIG. 2 is a recording belt section in another embodiment of the present invention. 3(a), 3(b), and 3(c) are side views showing an outline of a device according to still another embodiment of the present invention, and FIG. 4 is a schematic diagram showing a conventional radiation image information recording/reading device. It is a side view showing an outline. 1...Recording belt IA, IB...Storage phosphor section 4...First roller section 4a, 5a...Shaft 4b
, 5b... Roller 5... Second roller section 8... Recording belt section 10... Image recording section 20... Image reading section 24... Excitation light scanning means 25... Photoelectric reading Means 30... Erasing unit 41
...Motor 42...Guide member Fig. 2 Fig. 4

Claims (1)

[Scope of Claims] A recording belt consisting of a recording belt that is an endless belt having a stimulable phosphor layer and a pair of rollers that suspend and transport this recording belt so that the recording belt forms two surfaces. an image recording section that is provided opposite to one surface of the recording belt and accumulates and records a radiation image of the subject on the phosphor layer by irradiating radiation having image information; the other side of the recording belt; an excitation light scanning means that is provided opposite to the surface of the stimulable phosphor layer and scans excitation light onto the stimulable phosphor layer on which the radiation image is stored and recorded; an image reading section having a photoelectric reading means for reading the stimulated luminescent light to obtain an image signal; and a photoelectric reading section having a photoelectric reading means for reading the stimulated luminescence light and obtaining an image signal; The erasing section for emitting residual radiation energy on the phosphor layer of the lever, and the recording belt section are moved at a transport speed of the recording belt in a direction opposite to the transport direction of one surface of the recording belt when reading image information. A radiation image information recording/reading device comprising a moving means for moving at approximately constant speed.