JPS63259637A - Radiation image information recording and reading device - Google Patents

Abstract

PURPOSE:To permit easy macrophotographing as needed and formation of the titled device to a smaller size and lighter weight by providing a unit moving means for moving a recording and reading unit and changing the spacing between the unit and an object supporting part. CONSTITUTION:The small-sized recording and reading unit 20 which contains an accumulative fluorescent material sheet and is provided with image recording, reading and erasing functions is provided and is so constituted that the macrophotographing is executed by moving the entire part of this unit in place of feeding the accumulative fluorescent material sheet successively to image recording part, reading part and erasing parts along a circulating conveyance path. More specifically, this device is constituted of the object supporting part which supports a subject 11 to be irradiated with radiations 12, the recording and reading unit 20 and the unit moving means which moves the unit 2 so as to change the spacing from the object supporting part while the accumulative fluorescent material sheet existing in the photographing position maintains the direction facing the object supporting part. The easy macrophotographing to the accumulative type fluorescent material sheet and the reduction of the size are thereby permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for recording transmitted radiation image information of a subject.
A radiation image information recording and reading device reads the image information as an electrical image signal, and in particular, the radiation image information is stored and recorded on a stimulable phosphor sheet that stores radiated m1 energy, and enlarged photographing of the subject is performed. The present invention relates to a radiation image information recording/reading device that can be easily operated.

(Prior art) When a certain type of phosphor is irradiated with radiation 111 (X-rays, α-rays, β-rays, γ-rays, ultraviolet rays, electron beams, etc.), part of the energy of this radiation is accumulated in the phosphor. When the phosphor is then irradiated with excitation light such as visible light, the phosphor exhibits stimulated luminescence depending on the accumulated energy. A phosphor exhibiting such properties is called a stimulable phosphor (stimulable phosphor).

Using this stimulable phosphor, radiation image information of a subject such as a human body is recorded on a stimulable phosphor sheet (hereinafter referred to as a stimulable phosphor sheet), which is then scanned with excitation light and illuminated. A method has been proposed in which the stimulated luminescence is activated, the stimulated luminescence is read in a charged manner to obtain an image signal, and the image signal is processed to obtain a radiographic image of a subject that is suitable for diagnosis (for example, Japanese Patent Application Laid-Open No. 1983-1981). No. 12429, No. 55-116340, No. 55-163472, No. 56-11395, No. 56-104645, etc.). This I & Hiiragi image can be reproduced as a hard copy or on a CRT. In such a radiation image information recording and reproducing method, the stimulable phosphor sheet does not ultimately record image information, but temporarily stores image information in order to provide the image to the final recording medium as described above. Since the stimulable phosphor sheet is a carrier, the stimulable phosphor sheet may be used repeatedly, and such repeated use is extremely economical.

In order to reuse the stimulable phosphor sheet as described above, the radiation energy remaining in the stimulable phosphor sheet from which the stimulated luminescence light has been read can be used to
No. 2, No. 56-12599, the remaining number 1) J is released by irradiating the sheet with light or heat.
Erase the a1 image and reprint this stimulable phosphor sheet!
) 1a It can be used for image recording.

Therefore, the present applicant has developed a circulating conveyance means for conveying a stimulable phosphor sheet for storing and recording radiation images along a predetermined circulation path, and a means for irradiating radiation onto the sheet through a subject in the circulation path. an image recording unit that accumulates and records radiation image information of the subject on this sheet;
An excitation light source that is located in the circulation path and emits excitation light to scan a sheet on which radiation image information is stored and recorded in the image recording section, and reads stimulated luminescence light emitted from the sheet scanned by the excitation light. an image reading section comprising a photoelectric reading means for obtaining an image signal; and an image reading section which is located in the circulation path and remains on the sheet after the image reading is performed in the image reading section before an image is recorded on the sheet. We have previously proposed a radiation image information recording/reading device in which a stimulable phosphor sheet is repeatedly used by circulating the stimulable phosphor sheet between the various parts, and an erasing part that emits radiation energy. Showa 59-1
No. 92240). According to the radiographic image information recording/reading device having such a structure, radiographic image information can be recorded and read continuously and efficiently.

By the way, when recording radiation image information of a subject on a stimulable phosphor sheet (Ill shadow), the subject's chest, abdomen, etc. may be enlarged and recorded. This kind of enlarged photography is
This is done by appropriately changing the positional relationship between the radiation source, the subject, and the stimulable phosphor sheet. This enlarged photographing has the advantage of improving the degree of disassembly and reducing the influence of scattered radiation from the subject.

Therefore, the present applicant has previously developed a radiation image information recording/reading device that can easily perform the above-mentioned magnified imaging in a radiation image information recording/reading device of the type that circulates and conveys a stimulable phosphor sheet. proposed (Unexamined Japanese Patent Publication No. 1983-
No. 95339), this radiation image information recording/reading device is
It is equipped with the circulation conveyance means for the stimulable phosphor sheet as described above, an image recording section, an image reading section, and an erasing section, and a subject support section in the image recording section and a stimulable phosphor sheet holding section. It is characterized by being constructed in such a way that the distance between the two parts can be changed and the distance between the two parts can be changed.

According to the radiation image information recording/reading device having such a configuration, the above-mentioned enlarged imaging can be easily performed.

(The problem to be solved by the invention is that the above-mentioned configuration does not work!) j 11 The image information recording/reading device circulates and conveys a plurality of stimulable phosphor sheets along a circulation path to connect an image recording section and a reading section. , and are sent to the erasing section one after another, so there is a problem that the size tends to increase.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a radiation image information recording/reading device that can easily perform enlarged imaging on a stimulable phosphor sheet and is compact.

(Means and effects for solving the problem) The radiation image information recording/reading device of the present invention, instead of sequentially sending the stimulable phosphor sheet along the circulation conveyance path to the image recording section, the reading section, and the erasing section, Built-in stimulable phosphor sheet for image recording,
The device is characterized by a small recording/reading unit equipped with reading and erasing functions, and is configured so that the entire unit can be moved to take enlarged images. The distance between the subject supporting section to be supported, the above-mentioned recording/reading unit, and the subject supporting section is changed while maintaining the direction in which the stimulable phosphor sheet at the irradiation position faces the subject supporting section. It is composed of a unit moving means for moving the unit in the following manner.

The recording/reading unit described above includes a housing that houses a stimulable phosphor sheet inside and is formed to have vertical and horizontal dimensions approximately equal to the recording area of one screen of images on the sheet, and a stimulable phosphor sheet inside the housing. an image recording unit that stores and records transmitted radiation image information of the subject on the sheet by holding the sheet at a shadow position where the radiation that has passed through the subject is irradiated; an image reading unit that irradiates excitation light onto the stimulable phosphor sheet on which VJ has been recorded and photoelectrically reads the stimulated luminescence light emitted from the stimulable phosphor sheet by the irradiation with the excitation light to obtain an image signal; and an erasing unit, which is also arranged in the housing and releases the residual radiation energy on the MV4 phosphor sheet after reading the stimulated luminescence light, prior to recording an image on the sheet. It is equipped with the following.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 is a schematic side view showing a radiation image information recording and reading device according to an embodiment of the present invention. This radiographic image information recording/reading device includes a subject imaging platform 13 that supports a subject 11;
The object 1 is emitted from a radiation source 10 such as an X-ray tube.
A record reading unit 20 arranged at a position where radiation 12 such as X-rays transmitted through the record reading unit 14 is placed at a position to be irradiated with radiation 12 such as X-rays transmitted through the record reading unit 20; It is provided with a unit moving means 15 that moves in a direction to change the distance from the subject photographing table 13.

First, the recording/reading unit 20 will be described in detail with reference to FIGS. 2 and 3 showing its side and front shapes. The endless recording belt 1 is a stimulable phosphor sheet with a stimulable phosphor layer formed on almost the entire outer surface.
Inside the light-shielding housing 5, a first roller section 43 consisting of two rollers 41 and 42;
It is stretched over a second roller section 46 consisting of two rollers 44 and 45, which are arranged a predetermined distance M apart from each other. roller 4
Reference numerals 1, 42, and 44 are driven rollers that rotate as the recording belt 1 moves, while the roller 45 is connected to the rotating shaft 4 of the motor 48 by a power transmission means 47 such as a belt or chain.
8a is a driving roller connected to the drive roller 8a. This drive row 54
5 is rotated, the recording belt 1 rotates in the direction of the arrow in FIG.

When the radiation source 10 is activated after the subject 11 is placed in contact with the photographing stage 13, the radiation 12 that has passed through the subject 11 is irradiated onto the recording belt 1, and the radiation image information of the subject is transferred to the recording belt 1. It is stored and recorded in the stimulable phosphor layer. Moreover, the distance between the two roller parts 43 and 46 is
The length is approximately equal to the length of one screen of an image recorded (photographed) as described above.

Therefore, radiation image information is accumulated and recorded on the entire left side portion of the recording belt 1 in FIG. 2 due to the - times shadow. In this way, in this example, the image recording section 4 is set between the two rollers 41 and 44.

As shown in the figure, the photographing stage 13 is a part for supporting and positioning the photographed region of the subject 11 by bringing it into close contact with it. There is no need to place the parts in close contact.

The recording belt 1 is stopped while photography is being performed, but when photography is completed, a drive signal is sent from a controller (not shown) to the control circuit 3 in the unit 20, which drives the motor 48. The roller 45 is rotated,
Recording belt 1 is moved.

In this way, the portion of the recording belt 1 where the image has been recorded is
The recording belt 1 is conveyed to an image reading section 30 provided at the rear (on the right side in FIG. 2). Note that a rotary encoder 39 is attached to the rotating shaft 48a of the motor 48, and when the rotary encoder 39 detects that the recording belt 1 has rotated by about a hand rotation, the motor 48
will be stopped.

The image reading unit 30 includes a He-
An excitation light source 2) such as a Ne laser is provided to extend in the width direction of the recording belt 1 (the horizontal direction in FIG. A rotating polygon #124 which is a deflector is provided. The excitation light 2) A emitted from the excitation light source 2) is the third
After the optical path is changed by the group of mirrors 22 shown in the figure, the beam expander.

The light passes through an incident optical system 23 consisting of a cylindrical lens and the like and enters a rotating polygon mirror 24 . The excitation light 2)A reflected and deflected by the rotating polygon mirror 24 passes through a scanning optical system 25 consisting of an fθ lens and the like, as shown in FIG. 2, and further passes through five mirrors 26a, 26b, 26c.

After the optical path is changed by 26d and 26e, the roller 42
The light is incident on the recording belt 1 on the rear peripheral surface, and main scanning is performed on the belt 1 as described above. Note that the mirror 26c
is a cylindrical mirror that focuses the excitation light 2) A only in a plane parallel to the plane of the paper in FIG.
Due to the action of the cylindrical lens in the polygon mirror 3, even if the rotary polygon mirror 24 suffers from axis vibration, surface tilt, etc., pitch unevenness of scanning lines will not occur on the recording belt 1. When the main scanning of the excitation light 2)A is performed, the recording belt 1 is rotated by the drive roller 45 at a constant speed.

As a result, the part of the recording belt 1 where the excitation light 2)A is scanned at nj constant intervals and the radiation image information is stored and recorded.

Almost the entire surface thereof is irradiated with excitation light 2)A.

Stimulated luminescence light 40 is generated from the excitation light irradiation location of the recording belt 1 in an amount corresponding to the accumulated and recorded image information, and this stimulated luminescence light 40 is detected by the light M reading means 27. The photoelectric reading means 27 in this device includes a long photomultiplier (photomultiplier tube) 28 having a light-receiving surface extending in the main scanning direction over the length of the main scanning line, and the photomultiplier 28. A filter 29A1 provided on the light receiving surface of the filter 29A1, which selectively transmits only the stimulated luminescence light 40 and cuts off the excitation light 2)A reflected on the belt surface from entering the photomultiplier 28; and this filter 29A.
It consists of a light guide 29B attached on top to collect the stimulated luminescence light 40 and transmit it to the photomultiplier 28.

Further, the excitation light scanning line on the recording belt 1 is read by the photoelectric reading means 27.
A mirror 29C is arranged at a position facing from the opposite side. This mirror 29C efficiently reflects the stimulated luminescence light 40 emitted toward the mirror toward the light incident end of the light guide 29B.

The photomultiplier 28 has an electrode structure called a Venetian blind type, as shown in FIGS. 4 and 5, for example, and the main body 28A has a cylindrical shape, and the light receiving surface The main body 28A is placed opposite to the main body 28A.
A photocathode 28b is provided along the photocathode 28b, and a plurality of dynodes 28c (in this example, 13 dynodes) are stacked on top of each other through an insulating member 28d and fixed with a pin 28e to connect the multiplier 28f. It consists of This dynode 28c
Each of these is formed into a blind shape by making a large number of U-shaped cuts in a single conductive plate and bending it.

A shield electrode 280 is fixed with a pin 28e via an insulating member 28d below the multiplier 28f in the figure, and a III pole 28h is provided within the shield electrode 2BCJ. These electrodes are connected one-to-one to each terminal of the terminal group 28i provided at the side end of the main body 28A.

Note that the shield electrode 289 does not necessarily have to be provided.

FIG. 6 shows an electric circuit for driving the photomultiplier 28 to extract a photoelectric output, and each part of the photomultiplier 28 is given the same reference numeral as in FIGS. 4-5. . The operation of the photomultiplier 28 will be explained below with reference to FIG. Photocathode 2
A negative high voltage is applied to the terminal 8b via the negative high voltage application terminal 35a. The negative high voltage thus applied to the negative high voltage application terminal 35a is divided by the bleeder resistor group 35b and applied to the dynodes 28c. Further, the shield electrode 28g is grounded, and the anode 28h is connected to the leader resistor group 35b via a resistor 35C and to the amplifier 35d. Said stimulated luminescent light 4
The photoelectrons emitted from the cathode 28b after being irradiated with
When flowing toward the anode 28h, it hits the dynode 28c, thereby emitting secondary electrons from the dynode 28c. In this way, photoelectrons are multiplied one after another by each dynode 28C, and the resulting current is input to the amplifier 35d. In this way, the photoelectrically converted image information is taken out as an analog electrical signal (read image signal) S from the output terminal 35e of the amplifier 35d.

The part of the recording belt 1 from which image reading has been completed is further moved by the drive roller 45 and sent to the erasing section 33. The erasing unit 33 includes a box 31 and, for example, three erasing light sources 32 arranged inside the box 31. An erasing light source 32 consisting of a fluorescent lamp or the like is connected to the recording belt 1.
It mainly emits light in the excitation wavelength range of the stimulable phosphor layer, and the radiation energy remaining in the phosphor layer after image reading is transmitted to the entire image forming area as the recording belt 1 is moved. It is emitted from the phosphor layer by being irradiated with light. The portion of the recording belt 1 that has been erased in the erasing section 33 is again sent to the photographing position and is ready for new recording.

As the erasing light source 32, in addition to the above-mentioned fluorescent lamp, a tungsten lamp, a halogen lamp, an infrared lamp, a xenon flash lamp, etc. as shown in Japanese Patent Application Laid-Open No. 56-11392 may be arbitrarily selected and used. Further, the erasing unit 33 includes a large number of erasing light sources 32 as described above, and also includes, for example, an LED (L 1oht E 11itt
Ina D 1ode) may be constructed from a planar light source such as a panel or an EL (electro-luminescence) board in which 2-dimensionally arranged panels. Furthermore, a lead plate 2 for shielding radiation 12 is disposed inside the recording/reading unit 20, so that the radiation 12 emitted during the imaging is irradiated onto the recording belt 1 in the image reading section 30 and the erasing section 33 described above. or the radiation 1
@12 is prevented from having an adverse effect on the image reading section 30 and the erasing section 33.

The output signal (read image signal) S of the amplifier (log amplifier) 35d mentioned above is transmitted to the recording/reading unit 2 as shown in FIG.
0 and is digitized by the A/D converter 70. The digital read image signal representing transmitted radiation image information of the subject 11 thus obtained is sent to an image reproducing device 72 through an image processing device 71 that performs gradation processing, frequency processing, etc., for example. This image reproduction device @72 is, for example, a CRT.

It consists of an optical scanning recording device or the like, and displays the image carried by the image signal, that is, the transmitted radiation image of the subject 11 stored and recorded on the recording sheet 1 on a screen or reproduces it as a hard copy.

Next, enlarged projection will be explained. The unit moving means 15 described above has a plurality of screw rods 80 arranged to extend in the direction of the arrow in FIG. The screw rod 80 includes a screw rod 81 and a motor 82 that rotates the screw rod 80. In this configuration, when the motor 82 is rotated forward and backward, the threaded member 8
1 is screwed forward and backward along the screw rod 80, so that the distance between the recording/reading unit 20 and the photographing stage 13 can be arbitrarily changed.

At this time, the recording/reading unit 20 moves while maintaining the direction in which the recording belt 1 at the photographing position faces the photographing table 13. By moving the recording/reading unit 20 in this way, the positional relationship between the subject 11 and the recording belt 1 can be arbitrarily changed to perform enlarged pupil viewing of the subject 11.

Although the unit moving means 15 in this embodiment is configured to be able to move the recording/reading unit 20 steplessly, it may also be configured to move the unit 20 in steps. Furthermore, the radiographic image information recording/reading device of this embodiment is a chest-type device that performs imaging with the subject (subject) standing, but the present invention is a device that performs imaging with the subject (subject) in a standing position. The present invention can also be applied to a bed-type radiographic image information recording/reading apparatus that performs imaging in a state in which the subject support section is a bed-like subject mounting section.

In the recording/reading unit 20 described above, the recording belt 1 is stretched between two sets of roller parts 43 and 46 arranged at intervals approximately equal to the length of one radiation image screen, and image recording ( Since the unit 20 is configured to take pictures) and read images from the rear side, the unit 20 has a small housing 5 with vertical and horizontal dimensions that are slightly larger than the recording area of one image screen.
All the mechanisms are housed inside. By using the recording/reading unit 20 having such a configuration, the entire image information recording/reading apparatus can be made smaller and lighter. Note that in front of the recording belt 1 of the recording/reading unit 20, a so-called Butsky device may be provided, which includes a grid that absorbs scattered radiation from the subject 11, and a means for reciprocating the grid in addition to the grid.

As mentioned earlier, the record a reading unit 20 is housed in a small housing 5 that is slightly larger than the recording area of one image screen, but other units may be used as such a small record reading unit. It's okay to be hit. Hereinafter, other examples of small-sized recording/reading units that can be used in the apparatus of the present invention will be described. First, the recording/reading unit 100 shown in FIG. 7 will be explained. Note that this recording/reading unit 100 is applied to the bed-type radiation image information recording/reading device described above, and the entire unit is configured to move in the vertical direction for enlarged imaging.
The radiation transmitted through the subject is irradiated from the upper side in the figure (the same applies to the following embodiments). To move the recording/reading unit 100 in the vertical direction as described above, for example, means similar to the unit moving means 15 shown in FIG. 1 may be used.

A stimulable phosphor sheet 102 is fixed in a horizontal state to the image recording section 101 in the upper part of the housing 111 of the recording/reading unit 100. The housing 111 is formed to be slightly larger than the stimulable phosphor sheet 102. The stimulable phosphor sheet 102 has a stimulable phosphor layer 102B formed on a radiation-transparent substrate 102A.

A reading/erasing section 104 is provided below the sheet 102, in which an image reading section 120 and an erasing section 130 are placed close to each other and are housed integrally in the box 103. This reading/erasing unit 104 covers the area from the right end position (first digit M) shown by a solid line in FIG. 7(a) to the left end position (second position) shown by a solid line in FIG. 7(b). , can move back and forth while facing the seat 102. In this example, the moving path from the first position to the second position is the outward path, and
The movement 1111ii'g from the position to the first digit If is the return path. Further, the moving means 140 for reciprocating the reading and erasing section 104 includes, for example, a screw rod 141 extending in the moving direction of the reading and erasing section 104, a support section 142 screwed onto this screw rod 141, and a screw rod 1
41, a gear 144 meshing with this gear 143, and a motor 145 that rotates this gear 144 in both forward and reverse directions.
3, 144 to rotate the screw rod 141 to screw the support section 142 forward and backward, thereby reciprocating the reading and erasing section 104.

When this recording/reading unit 100 is used, as in the case described above, the stimulable phosphor sheet 102 is irradiated with radiation that is emitted from a radiation source and transmitted through the subject. As a result, radiation image information is accumulated and recorded on the phosphor layer 102B of the sheet 102.

The image reading unit 120 includes an excitation light source 12) such as a semiconductor laser.
, a condensing lens 122 provided in the optical path of the excitation light 12) A emitted from the excitation light source 12);
A rotating polygon R123 is an optical deflector that deflects the excitation light 12) A that has passed through the excitation light 12) in a direction perpendicular to the paper surface of FIG. 124a, 124b, 124
The stimulable phosphor sheet 102 is repeatedly scanned by the excitation light 12)A by the excitation light scanning means. On the other hand, along with this, the reading and erasing section 1
04 is moved by the moving means 140 at a constant speed to the left in FIG.
2) Receive irradiation of A. From the excitation light irradiation location of the sheet 102, stimulated luminescence light 4 corresponding to the accumulated and recorded image information is emitted.
0 is emitted, and this stimulated luminescence light 40 is transmitted to the image reading section 120.
is detected by the photoelectric reading means 27.

The photoelectric reading means 27 in this apparatus is formed similarly to that in the recording/reading unit 20 shown in FIG. 2.3, and includes a long photomultiplier 28 and a filter 29.
A, the light guide 29B, and the light guide 40 are connected to the light guide 2.
It consists of a mirror 29C that reflects the light toward the light receiving surface side of the light receiving surface 9B.

When the photoelectric reading means 27 finishes reading the image information, the reading/erasing section 104 is moved rightward in the figure from the second position to the first position. The erasing unit 130 includes an erasing light source 131 such as a fluorescent lamp extending in the excitation light main scanning direction;
A reflecting plate 132 is provided to reflect the downward light emitted from the erasing light source 131 toward the sheet surface side.

Further, in this embodiment, since the erasing light source 131 is always turned on, when recording and reading images, as shown in FIG.
As shown in FIG. 7(b), the erase light source 131 is located above the erasing light source Ijl to block the erasing light, and retreats onto the photomultiplier 28 as shown in FIG.
A moving shutter 133 is provided to expose the. Note that if the erasing light source 131 is turned on only during erasing and turned off at other times, it is not necessary to provide the movable shutter 133. The erasing light source 131 is the reading erasing unit 10
4 moves as described above, the entire surface of the sheet 102 is irradiated. The erasing light source 131 mainly emits light in the excitation wavelength range of the phosphor layer 102B, and the stimulable phosphor sheet 102 remains on the stimulable phosphor sheet 102 after the image is read! )J
I! Energy is released from the sheet 102 by irradiating the sheet 102 with such light. The stimulable phosphor sheet 102 that has been erased is now ready for new recording, and the reading/erasing unit 104 is returned to the first position.

In this way, in this recording/reading unit 100, one stimulable phosphor sheet 102 is fixedly held, and
By reciprocating the integrated reading and erasing section 104 to read and erase images, the length of the unit is reduced to nearly the length of one sheet.

Note that in the recording/reading unit 100 described above, the excitation light 12)A is scanned, and the stimulated luminescence light 40 is scanned at 74
For example, as shown in Japanese Patent Application No. 62-2) 957, excitation light is linearly irradiated onto the stimulable phosphor sheet 102, and The stimulated luminescence light 40 may be detected by a line sensor. This also applies to the recording/reading unit 20 shown in FIG. 2.3 described above and the recording/reading unit described below.

Next, referring to FIG. 8, another recording/reading unit used in the apparatus of the present invention will be described. In the housing 229 of the recording/reading unit 200 shown in FIG. 8, a first winding shaft 222 and a second winding shaft 223 are arranged parallel to each other with an interval between them.

The distance between the winding shafts 222 and 223 is set to be slightly longer than the length of one screen of recorded images on a stimulable phosphor sheet 226, which will be described later. These winding shafts 222.2
23 are motors 224.23 serving as sheet feeding means, respectively.
225, they are rotated counterclockwise and clockwise in the figure, respectively. As described above, one end side of the stimulable phosphor sheet 226 that can store and record radiographic image information is wound around the first winding shaft 222 . This stimulable phosphor sheet 226 is formed into a long strip using a flexible support, and the other end is attached to the second winding shaft 223.
, and is wound onto the second winding shaft 223 from this other end side. Further, the stimulable phosphor sheet 226 is held between the rollers 22 and 223 between the winding shafts 222 and 223.
It is designed to be stretched between 7°228. Here, the stimulable phosphor sheet 226 has a flexible support that allows good transmission of radiation irradiated from above as described above, and a stimulable phosphor sheet supported on the support. It is arranged so that the body layer is located on the lower side. Even when this recording/reading unit 200 is used, radiographic image recording (photography) of the subject is performed using the recording/reading unit 200 described above.
．． This is done in the same manner as when using 100. In other words, in this example, in the area between both rollers 227 and 228,
An image recording section 280 is set.

An image reading section 250 is provided below the stimulable phosphor sheet 226 at a position close to the second winding shaft 223 . The image reading unit 250 includes an excitation light source 251 such as a semiconductor laser, and a rotating polygon mirror 2 that is an optical deflector that reflects and deflects excitation light 252 emitted from the excitation light source 251.
53, the sheet 226 reflects the deflected excitation light 252
A drive roller 228 as a sub-scanning means that rotates at a constant speed and consists of a long mirror 259 that scans one-dimensionally above (more specifically, above the stimulable phosphor layer) and a nip roller that sandwiches the stimulable phosphor sheet 226. , a long photo multiplier 254 arranged such that its light receiving surface extends along the scanning line (main scanning line) on the stimulable phosphor sheet 226 by the excitation light 252, # and this long photo multiplier 254. A long condensing reflective mirror 2 arranged along
It consists of 55. In this example, a photomultiplier 25 with an electrode structure called a box type is used.
4 is used, but of course the type shown in FIG. 4.5 may also be used. After the radiation image of the subject is accumulated and recorded on the stimulable phosphor sheet 226 as described above, the sheet 226 is conveyed to the right in the figure at a constant speed by rotating the drive roller 228. At this time, the second
The winding shaft 223 is rotated and the M-laminated phosphor sheet 226 is
is wound around the shaft 223. In addition, the first winding shaft 222
An appropriate load is applied to the side by a known means, so that the stimulable phosphor sheet 226 is always maintained in a tensioned state. While the sheet 226 is conveyed, the excitation light source 251 and the rotating polygon mirror 253 are activated, and the excitation light 25
2 performs main scanning on the similar sheet 226.

Stimulated luminescence light 40 carrying radiation image information stored and recorded on the stimulable phosphor sheet 226 is emitted from a portion of the stimulable phosphor sheet 226 that is irradiated with the excitation light 252 . This stimulated luminescence light 40 is transmitted directly or to the condensing reflection mirror 2.
55 and is efficiently detected by a photomultiplier 254.

The main scanning of the excitation light 252 is performed as described above, and the stimulable phosphor sheet 226 is conveyed as described above and sub-scanning is performed, so that the stimulated luminescent light is emitted two-dimensionally from the sheet 226. 40 is read.

The portion of the stimulable phosphor sheet 1-226 whose image has been read as described above is wound around the second winding shaft 223 and stored there. At the same time, the first winding shaft 22
Another part of the stimulable phosphor sheet 228 that was wrapped around the rows 5227 and 228 is now stretched between the rows 5227 and 228, so the stimulable phosphor sheet 226 in this part is wrapped in the same manner as described above. new radiation image information can be recorded. In this way, radiation image information is recorded using approximately the entire length of the stimulable phosphor sheet 226, and all of the sheets 226 that had been wound and stored around the first winding shaft 222 are moved to the second @ winding shaft 223 side. After being fed out, the motor 224 is driven and the first winding shaft 222 is rotated counterclockwise in the figure. As a result, all of the stimulable phosphor sheet 226 wound around the second winding shaft 223 after image reading is returned to the first winding HJ222#J, but at this time, between the rollers 227 and 22g, The stimulable phosphor sheet 226 passes through the disposed erasing section 260, and the sheet 226 undergoes image (afterimage) erasure. This erase section 2
For example, the eraser 60 includes a plurality of erasing light sources 261 arranged below the stretched sheet 226. These erasing light sources 261 are composed of, for example, fluorescent lamps, etc., and mainly emit light in the excitation wavelength range of the stimulable phosphor of the sheet 226, and when the sheet 226 is returned to the first winding shaft 222 side, It will be lit. The radiation energy remaining in the stimulable phosphor sheet 226 after reading the image is
When the sheet 226 is irradiated with the above light, the light is emitted from the sheet 226. Note that the above erasing light is blocked by the light shielding plates 262 and 263, and the erasing light is blocked by the image reading section 250.
The light does not enter the long photo multiplier 254. Of course, if the long photo multiplier 254 is turned off after image reading is completed, the light shielding plate 2
62 and 263 are unnecessary.

In this way, the first winding shaft 222 stores the stimulable phosphor sheet 226 whose image (afterimage) has been erased to the extent that radiation image information can be recorded again. It becomes possible to repeat image recording (photography) and reading of images.

In this embodiment, a secondary erasing light source 270 for performing so-called secondary erasing is provided between the first winding shaft 222 and the image recording section 280.

This secondary erasing light source 270 is the erasing light source 2 of the erasing unit 260.
61, and irradiates the stimulable phosphor sheet 226 with erasing light when the sheet 226 is fed out from the first winding shaft 222 for recording image information. The stimulable phosphor sheet 226 is the erasing section 260
If the sheet 226 is stored on the first winding shaft 222 without being used for a long period of time after the image (afterimage) has been erased at Radiation energy (which is a component of noise to the stored recorded information) due to elements and rings *MIIHa may be accumulated, but as described above, just before image recording, the secondary erasing light source 270 is used to remove radiation energy from the sheet 22.
By irradiating erasing light on 6, this release! 14I! i
! Energy is also released. Note that the secondary erasing light is blocked by light shielding plates 271 and 272 so that it does not irradiate the stimulable phosphor sheet 226 before image reading.

In the above example, recording (photographing) and reading are performed alternately at rJ, which winds up the stimulable phosphor sheet 22G from the first winding shaft 222 to the second winding shaft 223. Then, the second winding shaft 2
23 to the first winding shaft 222.
It is also possible to read and erase the image 9 when rewinding the image 6.

Next, with reference to FIGS. 9, 10 and 11, still another example of the recording/reading unit used in the apparatus of the present invention will be described. In the housing 325 of the recording/reading unit 300, a stimulable phosphor sheet 322 is disposed, for example, in which a stimulable phosphor layer 322B as described above is formed on a plate-shaped transparent support 322A. ing. This sheet 32
In No. 2, the support 322A is formed larger than the phosphor layer 322B, and the portion around the phosphor layer to the support 322 is a holding portion 322a.

322 b, 322 c, and 322 d. Further, in this embodiment, the sheet 322 has a phosphor 1
11322B is arranged below the support body 322A. The sheet 322 includes a holding portion 322b,
322 d is slidably supported on the rail 323,
It is held within a housing 325. That is, this rail 32
The upper part of the housing 325 containing 3 is the radiation m image record a (W shadow)
Image recording section 3 that sometimes holds stimulable phosphor sheet 322
It is said to be 32. The f11 horizontal dimension of the housing 325 is set to be slightly larger than the vertical and horizontal dimensions of the stimulable phosphor sheet 322. Then, as shown in FIG.
An elongated opening 325 a facing the end surface of the stimulable phosphor sheet 322 is provided at one end of the stimulable phosphor sheet 322 .

This housing 325, except for the portion facing the image recording unit 332, is covered with a radiation absorbing material such as a lead plate to prevent the stimulable phosphor sheet 322 from being exposed to environmental radiation other than imaging radiation. It is designed not to cause Capri.

Even when using this recording/reading unit 300, radiation image information recording (photography) is performed by the recording/reading unit 2 described earlier.
0.100 and 200, and the stimulable phosphor layer 322B formed on the bottom surface of the stimulable phosphor sheet 322 (in detail, the stimulable phosphor layer 322B formed on the lower surface side of this sheet 322)
(b) Radiographic image information of the subject is accumulated and recorded.

An image reading section 350 is provided below the stimulable phosphor sheet 322 within the housing 325 . The image reading unit 350 includes an excitation light source 351 such as a laser, a mirror 353 that reflects excitation light 352 emitted from the excitation light source 351, a beam expander 354 that sets the beam diameter of the excitation light 352 to a predetermined value, and an excitation light A cylindrical lens 355 makes the light 352 incident on the mirror surface of a rotating polygon mirror 356 (described later) so as to form a line image, a rotating polygon mirror 356 is an optical deflector that reflects and deflects the excitation light 352, and the deflected excitation light 352 is reflected. The phosphor layer 322B of the sheet 322
a long mirror 357 that is scanned one-dimensionally above;
A drive roller 358 as a sub-scanning means, which is composed of a pair of nip rollers that sandwich the stimulable phosphor sheet 322 and rotates at a constant speed, and a stimulable phosphor sheet 322 that is illuminated by excitation light 352
A long photo multiplier 359 arranged so that the light receiving surface extends along the upper scanning S (main scanning line), and a long light collecting device arranged along this long photo multiplier 359. It has a reflecting mirror 360. Furthermore, an f/theta lens 361 and a cylindrical lens 362 are arranged between the rotating polygon mirror 35θ and the mirror 357, so that the excitation light 352 remains constant at any position on the stimulable phosphor sheet 322. It is designed to focus on the beam diameter.

Subject 1 is placed on the stimulable phosphor sheet 322 as described above.
After the radiation image information of No. 1 is recorded on the vehicle area, the drive roller 3
58 is rotated, the sheet 322 is moved at a constant speed toward the opening 325a (the state shown in FIG. 11).
. Note that when radiation image information is recorded, the driving roller 358 holds the holding portion 322a at one end of the stimulable phosphor sheet 322, so if the driving roller 358 is rotated after recording the image, the stimulable phosphor is sheet 322
can be immediately moved as above. While the sheet 322 is conveyed, the excitation light source 351 and the rotating polygon 13
5θ is activated and excitation light 352 is scanned over the sheet 322.

The stimulated luminescent light 40 thus emitted is efficiently detected by the photomultiplier 359 either directly or by being reflected by the condensing reflecting mirror 360. While the main scanning of the excitation light 352 is performed as described above, the stimulable phosphor sheet 322 is moved as described above to perform sub-scanning.
The stimulated luminescence light 40 is read out dimensionally.

As mentioned above, in this record a reading unit 300,
When the stimulable phosphor sheet 322 is moved for nj constant scanning, the sheet 322 protrudes out of the housing 325 through the opening 325a, as shown in FIG.

Since the excitation light 352 scans the sheet 322 at a position close to the opening 325a, when the image reading is completed, the stimulable phosphor sheet 32
2 comes to protrude outside the housing 325.

Therefore, the housing 325 is formed to have a slightly larger size than the seat 322 without the need to secure a space for the movement of the seat 322.

When image reading is completed as described above, the holding portion 322C of the stimulable phosphor sheet 322 is held between the drive rollers 358. When this state is reached, the drive roller 358 is then rotated in the opposite direction to that in the case of image reading described above, whereby the stimulable phosphor sheet 322
is returned to the image recording section 332 inside the housing 325. At this time, the stimulable phosphor sheet 322 passes through an erasing section 370 provided in a position close to the opening 325a in the housing 325, and the sheet 322 undergoes image (afterimage) erasure. This erasing section 370 is composed of an erasing light source 371 placed above the sheet 322.

In this way, the stimulable phosphor sheet 322 whose image (afterimage) has been erased to the extent that radiation exposure information can be recorded again is stored in the housing 325. It becomes possible to repeat image recording (Il! shadow) and reading. Note that the erasing unit 370 is
In addition to the erase light source 371 as described above, a planar light source such as an El (electroluminescence) plate is arranged to face the stimulable phosphor sheet 322 at the image recording position from below, that is, from the side of the stimulable phosphor layer 322B. It can also be arranged and configured as follows. In this case, the support 322A of the sheet 322 does not need to be made of a transparent member.

When such a configuration is adopted, the above-mentioned secondary erasing can be easily performed using a planar light source.

<Effects of the Invention> As explained in detail above, in the radiation image information recording/reading apparatus of the present invention, a unit moving means for moving the recording/reading unit is provided, so that the distance between the unit and the subject support section can be changed as appropriate. Therefore, according to the present apparatus, enlarged photographing can be carried out at will and easily. The device of the present invention uses a recording/reading unit in which an image recording section, a reading section, and an erasing section are all housed in a housing whose size is approximately the same as the recording area of one radiation image screen. Compared to conventional devices that circulate sheets, this system is extremely small and lightweight.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of an apparatus according to an embodiment of the present invention, FIGS. 2 and 3 are a side view and a front view, respectively, of the recording/reading unit of the apparatus according to the embodiment, and FIGS. 4 and 5 are respectively , a partially cutaway perspective view and a side sectional view of the photomultiplier used in the recording/reading unit, FIG. 6 is a circuit diagram showing the electric circuit of the photomultiplier, and FIG. 7 is a diagram showing the electrical circuit of the photomultiplier used in the device of the present invention. FIG. 8 is an elevational view showing yet another example of the record reading unit used in the apparatus of the present invention; FIG. 9 is an elevational view showing another example of the record read unit used in the apparatus of the present invention. FIGS. 10 and 11, which are schematic perspective views showing still another example of the unit, are partially cutaway elevational views showing the recording/reading unit of FIG. 9 in an image recording state and an image reading state, respectively. i, 102, 226, 322... stimulable phosphor sheet 4, 101, 280, 332... image recording section 5, 111, 229, 325... housing 1
0...Radiation source 11...Subject 12...
・Radiation @ 13...Photograph table 15...Unit moving means 20.100, 200, 300...Recording/reading unit 2), 12), 251, 351...Excitation light source 2)A, 12) A, 252, 352... Excitation light 24, 123, 253, 356... Rotating polygon mirror 28, 254, 359... Photo multiplier
30, 120, 250, 350... image reading section 32,
131, 261, 371... Erasing light sources 33, 13
0, 260, 370... Erasing section 40... Stimulated luminescence light 43.4G... Roller section 45, 228
, 358... Drive roller 48, 82.145, 22
4, 225...Motor 80...Screw rod 81...Screwing member S...Reading image signal Fig. 2 Fig. 3 41.42 Fig. 8 Fig. 9 Fig. 10 Fig. 11

Claims (5)

[Claims] (1) A subject support part that supports a subject to be irradiated with radiation; a housing that houses a stimulable phosphor sheet inside and has vertical and horizontal dimensions approximately equal to the recording area of one screen of images on the sheet; an image recording unit that holds a stimulable phosphor sheet at a photographing position where radiation transmitted through the subject is irradiated within the housing and stores and records transmitted radiation image information of the subject on the sheet; , irradiate excitation light onto a stimulable phosphor sheet on which radiation image information has been accumulated and recorded, and photoelectrically read the stimulated luminescent light emitted from the stimulable phosphor sheet by irradiating the excitation light to obtain an image signal. an image reading unit disposed within the casing to emit residual radiation energy on the stimulable phosphor sheet prior to recording an image on the stimulable phosphor sheet after reading the stimulated luminescent light; a recording/reading unit comprising an erasing section, and changing the distance between the recording/reading unit and the subject supporting section while maintaining the direction in which the stimulable phosphor sheet at the photographing position faces the subject supporting section; A radiation image information recording/reading device comprising a unit moving means for moving the unit in the following manner. (2) The stimulable phosphor sheet is formed in the shape of an endless belt, and the endless belt-shaped stimulable phosphor sheet is placed between two sets of rollers arranged at a distance approximately equal to the length of one image screen. The stimulable phosphor sheet is stretched and held at the imaging position, and when the part of the stimulable phosphor sheet on which the radiation image has been accumulated and recorded is sent out from the imaging position and the other part of the sheet is sent to the imaging position, 2. The radiation image information recording/reading apparatus according to claim 1, wherein the radiation image information recording/reading apparatus is configured to read the stimulated luminescence light by sub-scanning the excitation light by movement. (3) The stimulable phosphor sheet is fixed at the photographing position, and the image reading unit and the erasing unit are mounted on a moving body that moves along the surface of the stimulable phosphor sheet, The radiation image information recording/reading device according to claim 1, wherein the radiation image information recording/reading device is configured to perform sub-scanning of the excitation light by movement to read the stimulated luminescence light and erase the image. . (4) The stimulable phosphor sheet is formed as a band-shaped flexible sheet, and one end and the other end of the stimulable phosphor sheet are a first
The stimulable phosphor sheet is wound around a second winding shaft and stretched at a photographing position between the two shafts, and the excitation light is sub-scanned by winding and moving the stimulable phosphor sheet between the two shafts. 2. The radiation image information recording/reading device according to claim 1, wherein the radiation image information recording/reading device is configured to read the stimulated luminescence light. (5) An opening through which the sheet passes is provided at one end of the casing opposite to the end surface of the stimulable phosphor sheet, and the stimulable phosphor sheet is passed from the image recording section to the outside of the casing through the opening. The radiation image information record/reader according to claim 1, wherein the radiation image information record/reader is configured to read the stimulated luminescence light by sub-scanning the excitation light by moving it in a protruding manner. Device.