JP2835622B2 - Radiation image reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to recording radiation image information on a stimulable phosphor,
The present invention relates to a radiation image reading apparatus that reads out the recorded image information by excitation scanning, and more particularly to a radiation image reading apparatus that can obtain a high-sensitivity, high-quality image.

[Background of the Invention]

When a stimulable phosphor is irradiated with radiation (X-ray, α-ray, β-ray, γ-ray, ultraviolet ray, etc.), part of the energy of this radiation is stored and recorded in the phosphor, and then the excitation light is applied to the phosphor. Upon irradiation, the phosphor emits stimulating light in accordance with the stored energy.

The radiation image conversion plate is a plate having a stimulable phosphor layer having such characteristics (hereinafter simply referred to as a plate except for special cases), and is used for radiation (X
Line) An image can be recorded as a latent image, and when this latent image portion is irradiated with excitation light such as laser light, photostimulated emission having an intensity corresponding to the density of the latent image occurs. Therefore, if the stimulated emission light is detected by a photodetector such as a photomultiplier (photomultiplier) and appropriately processed, a recorded radiation image can be obtained. This final image may be played back as a hard copy or on a CRT.

In this way, the plate temporarily stores the image information and gives the image to the final display / recording medium,
It is preferably used repeatedly, and the accumulated residual image on the plate which has been excited and read is generally removed by an erasing light source and used again. In this case, an image capturing unit that radiates radiation through a subject to a plate provided with a stimulable phosphor layer, an image reading unit that excites and reads an image stored and recorded on the plate, and radiation energy remaining on the plate after reading It is extremely advantageous to compactly store an image erasing unit and the like for preparing the next recording in one apparatus when loading the moving station such as an X-ray photographing car.

Conventionally, various techniques have been disclosed regarding plate transport and image reading techniques. However, if a reading section is separately provided, the apparatus becomes large, and if the optical system is fixed, troubles due to plate transport (generation of scratches due to jams or the like) occur. And have other problems.

In addition, when radiation is irradiated from the support side of the plate and reading is performed from the phosphor side, the support absorbs X-rays, so that there is a problem that X-ray quantum mottle with lack of sharpness is easily generated. . Furthermore, since the material of the support is limited to a material excellent in X-ray transmission, there is a restriction that the range of choice is narrow.

[Object of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a radiation image reading apparatus capable of obtaining high-sensitivity, high-contrast, high-sharpness image information, having a compact apparatus, and free from trouble in transporting a plate during image reading.

[Configuration of the invention]

The object of the present invention is to irradiate radiation onto a radiation image conversion plate having a stimulable phosphor layer to accumulate and record radiation image information, and scan the plate with excitation light after the recording to record and accumulate the radiation image information. In the radiation image reading apparatus configured to photoelectrically read the radiation image information, the plate is retracted and moved to a predetermined place behind the plate while maintaining the parallel state with respect to the plate surface after the irradiation. A reading optical system that moves the reading optical system to perform reading. And irradiating radiation onto a radiation image conversion plate having a stimulable phosphor layer to accumulate and record radiation image information, and after the recording, scan the plate with excitation light to record the radiation image information that has been accumulated and recorded. In the radiation image reading device configured to photoelectrically read the plate, after the irradiation, the plate is moved to a predetermined place behind by rotation around a side on an extension of the plate surface, and fixed there. After that, the reading is performed by moving the reading optical system to perform reading.

The apparatus of the present invention is used in a radiation image conversion method schematically shown in FIG.

That is, in FIG. 1, 11 is a radiation generator, 12
Is a subject, 13 is a radiation image conversion plate, 14 is a photostimulation excitation light source, 15 is a photoelectric conversion device that detects photostimulated emission emitted from the conversion plate, and 16 is a device that reproduces a signal detected by 15 as an image. Reference numeral 17 denotes a device for displaying a reproduced image, and reference numeral 18 denotes a filter that separates stimulated excitation light and stimulated emission and transmits only stimulated emission. Note that after 15 the optical information from 13 can be reproduced in any form as an image, and is not limited to the above.

As shown in FIG. 1, the radiation from the radiation generator 11 enters the conversion plate 13 through the subject 12. The incident radiation is absorbed by the stimulable phosphor layer of the plate 13 and its energy is accumulated, thereby forming a radiation transmission image.

Next, the accumulated image is excited by stimulating light from the stimulating light source 14 and emitted as stimulating light. Since the intensity of the emitted photostimulated luminescence is proportional to the amount of accumulated radiation energy, this optical signal is photoelectrically converted by a photoelectric conversion device 15 such as a photomultiplier tube, and reproduced as an image by an image reproduction device 16, and the image is reproduced. By displaying the image on the display device 17, a radiographic image of the subject can be observed.

〔Example〕

 Next, the present invention will be described in more detail by way of examples.

FIG. 2 is a configuration diagram showing an embodiment of the radiation image reading apparatus, which is applied to chest X-ray photography.

X-rays controlled by the X-ray generator 1 are emitted toward the subject 2, and the plate 4 fixed to a frame in the radiation image reading device 3 radiates energy according to the X-ray transmission distribution of the subject 2 to the plate 4. It accumulates in the phosphor layer.

The irradiated 4 moves and returns to 4 ', and the excitation, reading, and
It is excited by excitation light from the shaped light beam of the erasing unit 5. In order to use the plate 4 'repeatedly, it is necessary to erase the afterimage, and this erasing is performed by an erasing lamp (for example, a halogen lamp) provided in the unit 5 together with the light beam generator. The plate 4 'in the reusable state returns to the position 4 and returns to the photographable state.

FIG. 3 shows an embodiment similar to that of FIG. 2, but the plate 4 'of FIG. 2 moves backward while maintaining the parallel state with respect to the plate surface 4, while the plate 4' of FIG. Plate 4 4 '
To move to.

The feature of the present invention resides in that, after moving the plate to which the radiation has been irradiated and fixing the plate at a predetermined place, reading is performed from the optical body layer side which has been subjected to the radiation irradiation by the optical system. In addition to that shown in FIG. 3, there is a rotational movement about one side of the plate. Regarding the rotational movement, each side of the plate may be good, and this is schematically shown in FIGS. 4 (a), (b), (c) and (d).

The present invention is applied not only to the three-dimensional type as shown in FIGS. 1 and 2 but also to the recumbent type as shown in FIG. In this case, the same style as the standing type can be used for the movement from the plate 4 to the 4 'and the arrangement of the optical system 5, etc., but after the radiation irradiation, the plate 4 moves to the 4' and the vibration isolator 6 is inserted at the same time. By doing so, it is possible to prevent the reading accuracy from being reduced due to the vibration of the imaging table 3 caused by the movement of the subject 2, which is more preferable.

FIGS. 6A to 6F show an example of a means for moving the plate or the plate holding means. (A) and (b) show the moving state of the plate shown in FIG. 2, (c), (d),
(E) and (f) are examples of the moving means in the moving state of the plate shown in FIGS. 3 and 4.

FIG. 7 is a view showing a mechanism portion in which the plate 4 is moved and temporarily fixed at 4 ', and the excitation / read / erase unit 30 is movably provided. Reference numeral 21 denotes a frame that forms an outer frame of the main body of the device 5. Reference numeral 22 denotes a panel transport member. From the start to the end of reading, the panel is fixed at the position 4 '.

The entire excitation / read / erase unit 30 is a movable plate 31
In a fixed state. A female screw (not shown) is fixed to the moving plate 31, and the female screw is
And screwed into a female screw rod 26 which is rotated by a motor 25 attached to the motor. 27 is a guide bar. Therefore, by driving the motor 25, the movable plate 31 can be moved in the direction of the arrow Y or in the direction opposite thereto.

A light beam generator 6 is mounted on the movable plate 31 (not shown in FIG. 6), and a beam from the light beam generator 6 is provided with an optical system (not shown) such as a beam expander for shaping (expanding) the beam diameter. The light is reflected by a scanner 7 such as a galvanometer mirror or a polygon mirror (in the figure, a galvanometer mirror is shown), becomes scanning light, passes through a condenser lens 32 such as an fθ lens for focus adjustment, and is reflected by a reflection mirror 71. The optical path is changed by -73 to become the excitation light 81.

The plate 4 'is temporarily fixed to the right of the moving range of the excitation / read / erase unit 30 in FIG. 7, and the excitation light 81 scans the plate 4' as a scanning line 80. Is done.

The photomultiplier 10 is fixed to the moving plate 31, and the photomultiplier 10
The light-collecting end face 8a of the light-collecting body 8 that transmits stimulated emission light to 10 is located near the scanning line 80 and is arranged in parallel with the scanning line 80.

Reference numeral 9 denotes a filter that allows only light in the stimulated emission wavelength region among the light introduced from the light collector 8 to pass.

In the apparatus 5, in the main scanning in the X direction on the plate 4 '(the direction perpendicular to the plane of the drawing in FIG. 7), the beam emitted from the light beam emitting unit 6 is swung by the scanner 7 (scanning). The focusing is performed by the condenser lens 32 to focus on the surface of the plate 4.

On the other hand, in this embodiment, the sub-scanning in the Y direction is performed by moving the movable plate 31 in the Y direction, that is, by moving the excitation / read / erase unit 30 itself, in this embodiment.

Therefore, the plate 4 'can be two-dimensionally scanned with the excitation light 81, and when stimulated emission light corresponding to the density of the latent image is generated in a portion scanned by the excitation light 81, the emission is collected. The light is condensed by the optical body 8 and guided to the photomultiplier 10, where it is detected and becomes an electric signal. Then, the electric signal is processed in synchronization with the main scanning and the sub-scanning, so that an image recorded as a latent image on the plate 4 'can be reproduced.

In the apparatus of the present invention, since the excitation / read / erase unit 30 is integrally formed as described above, mutual displacement (deviation) of each part is reduced, and more stable image reading is possible. .

Further, in the above example, the optical path is bent by the reflecting mirrors 71 to 73. In this case, the substantial optical path length between the scanner 7 and the scanning line 80 on the plate 4 'is not changed. Since the space occupied by the fan-shaped scanning light can be reduced, inserting a plurality of such reflecting mirrors in the optical path greatly contributes to downsizing of the apparatus.

In FIG. 7, the excitation light 81 is incident on the plate 4 'from obliquely below. If the excitation light is incident on the plate 4 'in the vertical direction, the excitation light returns directly to the light beam generator 6 due to reflection on the plate 4' surface, which may lead to fluctuations in the light beam power. is there.

In the mechanism for moving the excitation / read / erase unit 30,
It is preferable to use a laser light source, particularly a semiconductor laser, as the light beam generator 6 in terms of compactness, light weight, and low cost. However, when reflected light enters the active region of the semiconductor laser, the laser oscillation mode changes. The light beam power greatly fluctuates, which adversely affects image reading.
Therefore, in the present embodiment, as described above, the excitation light 81 is incident on the plate 4 'from an oblique direction.

In this embodiment, the incident end face of the light collector 8 is arranged substantially parallel to the plate 4 'in FIG.
With such a configuration, the light-collecting efficiency of stimulated emission light generated on the plate 4 'is maximized, and read image information with a high S / N ratio can be obtained.

By the way, in order to allow the plate 4 to be used repeatedly, it is necessary to erase the latent image remaining after reading. Since this erasing can be performed by irradiating the plate 4 'with intense light, as shown in FIG. 7, an erasing lamp 33 is provided substantially in parallel with the condenser 8, and this lamp 33 is moved to the movable plate 31. Should be fixed to. The lamp 33 is covered with a reflector 34 to efficiently irradiate the light from the lamp 4 'to the plate 4', and is provided between the lamp 4 and the plate 4 'so as to face the plate 4' only when necessary. The shutter 35 is interposed.

If the erasing lamp 33 is mounted at a position close to the plate 4 ', power consumption is small, and the lamp 33 itself can be reduced in size and weight. Further, as shown in FIG. 7, by passing the excitation light 81 between the light collector 8 and the erasing lamp 33, the dead space is reduced, and the device 5 itself can be made much more compact. Erase lamp used here
33 is a halogen lamp.

Since the light collector 8 and the erasing lamp 33 are integrated in the unit 30, it is possible to sequentially erase the read portion while performing image reading. The scanning line that is incident on the optical body 8 or is currently being read
Irradiation of 80 causes a problem that it becomes a large noise and is detected by the photomultiplier 10.

Therefore, in order to prevent this, it is preferable to adopt a process in which reading is performed during sub-scanning in the direction of arrow Y and erasing is performed when returning to the opposite direction.

Also, in order to prevent the photocathode of the photomultiplier 10 from deteriorating due to light at the time of erasing by the lamp 33, the scanning lines 80
It is preferable to provide a light-blocking means 36 in the optical path from to the photomultiplier 10. In this way, the lamp light to the photomultiplier 10 can be cut off, the service life of the photomultiplier 10 can be extended, and the trouble of the next reading can be reduced.

In this case, the light-shielding plate used as the light-shielding means 36 may be replaced with a filter 9 that transmits stimulated emission light and attenuates excitation light.

As the light shielding means 36, a liquid crystal shutter can be used. Further, it is preferable that the light shielding means 36 can shield the erasing lamp light and also shield radiation at the time of photographing. In this case, a material to which a lead plate or the like is added is preferable.

By the way, the structure in which the unit 30 is moved as described above, and the unit
By moving 30, a radiation detector can be used instead, and in this case, there is no need to newly provide a radiation detector, and it is not necessary to perform pre-reading or the like prior to the original reading. .

That is, the photodetector such as the photomultiplier 10 in the excitation / reading unit 30 can also be used as a radiation detector, and the radiation dose generated at the time of radiation irradiation, instantaneous light emission, When the specified amount is reached, a signal for stopping the irradiation of radiation is generated to prevent fluctuations in the amount of radiation to the plate 4 'and stabilize image recording conditions.
Accurately detect and measure the receipt of radiation on plate 4 ',
The reading gain of the stimulated emission can be adjusted.

On the moving excitation / reading unit 30, a current / voltage converter, an amplifier and an A / D converter can be output from a digital signal instead of an analog signal which is easily affected by noise. Preferred from the point.

In the present invention, in addition to the above-described embodiment, the excitation / reading unit 30 may employ a method of guiding excitation light onto the phosphor surface using an optical fiber as shown in FIG. In this case, the moving distance of the plate is shorter than that of the above-described embodiment, which can be made even more compact in the size of the entire apparatus, which is more preferable.

In the present invention, the plate is temporarily fixed at the time of reading, and reading is performed only by the reciprocating motion of the excitation / read / erase unit (optical system). The accuracy of the fixed position of the plate may be noted, and the accuracy required for the movement of the plate is relatively low.

If the movement of the plate in the present invention is a linear movement in a direction perpendicular to the plate surface or a rotational movement about one side of the plate or one side extending from the plate surface as an axis, the whole apparatus can be downsized. The transport mechanism can also be simplified. Also, during the movement of the plate, contact with the transporting means or the plate holding means is limited to the end face and / or one side of the plate, so that the plate is less damaged and scratches on the plate surface appear as noise on the image. Nothing.

The stimulable phosphor used in the plate 4 of the present invention, after being irradiated with the first light or high-energy radiation,
It is a phosphor that emits photostimulated light corresponding to the initial dose of light or high-energy radiation when stimulated by light, thermal, mechanical, chemical, or electrical (stimulated excitation). In view of this, the phosphor preferably emits stimulable light by stimulating light having a wavelength of 500 nm or more. BaSO The stimulable phosphor, as described, for example JP-A-48-8047 _4: AX, SrSO ₄ as described in JP-A-48-80489: AX, JP 53-392
77 No. _{Li 2 B 4 O 7: Cu} , Ag , etc., Li ₂ O · in JP 54-47883
(B ₂ O ₂ ) x: Cu and Li ₂ O · (B ₂ O ₂ ) x · Cu, Ag, etc., SrS of US Pat. No. 3,859,527; Ce, Sm, SrS: Eu, Sm, La ₂ O ₂ O: Eu, Sm
And a phosphor represented by (Zn, Cd) S: Mn.
ZnS: Cu, Pb phosphor described in No. 1, general formula BaO.xAl ₂ O ₃ : E
Barium aluminate phosphor represented by u, general formula M ^II Ox
SiO _2: alkaline earth metal silicate phosphor represented by A, the general formulas described in JP-A-55-12143 (Ba _1- x _- yMgxCay)
FX: alkaline earth fluoride halide phosphor represented by eEu ²⁺ , phosphor represented by the general formula LnOX: xA described in JP-A-55-12144, JP-A-55-12145 A phosphor represented by the general formula (Ba ₁ -xM ^II x) FX: yA described in JP-A-55-8438.
Phosphor represented by the general formula BaFX: xCe, yA described in No. 9,
General formula M ^II FXxA: yLn described in JP-A-55-160078
A rare-earth activated bivalent metal fluorohalide phosphor represented by the general formula ZnS: A, CdS: A, (Zn, Cd): A, ZnS: A, X and
Phosphor represented by CdS: A, X, represented by the following general formulas xM ₃ (PO ₄ ) ₂ · NX ₂ : yA and M ₃ (PO ₄ ) ₂ : y described in JP-A-59-38278.
Phosphor represented by A, the following formula nReX ₃ · mAX _'2: xEu and
_{nReX 3 · mAX '2: xEu} , yEu, phosphor, and the following general formula M ^I X · aM ^II X represented by ^{_{ySm' 2 · Bm II X "}} 3 alkali halide phosphor represented by cA and JP Akira 61-228400 Patent general formula X ^I X according:. bismuth-activated alkali halide phosphor, etc. represented by xBi, among others alkali halide phosphor,
It is preferable because the phosphor layer can be easily formed by a method such as vapor deposition or sputtering.

However, the stimulable phosphor used in the plate according to the present invention is not limited to the above-described phosphor, and any phosphor that emits stimulable luminescence when irradiated with stimulating excitation light after irradiation with radiation. Any phosphor may be used as long as it is used.

The plate of the present invention may be a phosphor layer group composed of one or more phosphor layers containing at least one kind of the stimulable phosphor described above. Further, the stimulable phosphor contained in each phosphor layer may be the same or different.

The phosphor layer of the present invention may be formed by either a coating method or a vapor deposition method.

The layer thickness of the phosphor layer of the plate of the present invention varies depending on the sensitivity of the target plate to radiation, the type of stimulable phosphor, and the like.
μm, more preferably selected from the range of 20 μm to 800 μm, when containing a binder 20 μm
m to 1000 μm, more preferably 50 μm to 500 μm
Is preferably selected from the range.

Examples of the support used in the present invention include various polymer materials, glass such as crystallized glass, ceramics, and metals.

Examples of the polymer material include films such as cellulose acetate, polyester, polyethylene terephthalate, polyamide, polyimide, triacetate, and polycarbonate. Examples of the metal include a metal sheet or metal plate of aluminum, iron, copper, chromium, or the like, or a metal sheet or metal plate having a coating layer of the metal oxide. Examples of the glass include chemically strengthened glass and crystallized glass. Examples of the ceramic include a sintered plate of alumina or zirconia.

Further, the layer thickness of these supports varies depending on the material of the support to be used and the like, but is generally 80 μm to 5 mm, and from the viewpoint of easy handling, preferably 200 μm to 3 mm.
It is.

The surface of the support may be a smooth surface or a mat surface for the purpose of improving the adhesion to the upper layer.
In addition, the surface of the support may be an uneven surface, or may be a surface structure in which minute tile plates independent of each other are densely arranged.

In the plate of the present invention, at least one or more protective layers can be further provided on the phosphor layer in order to protect the phosphor layer from a chemical stimulus from the external atmosphere, especially from moisture.

As a material for forming such a protective layer, a material having good light-transmitting properties and which can be formed into a sheet shape can be used. Further, the protective layer preferably has a high transmittance in a wide wavelength range, and more preferably has a transmittance of 80% or more, in order to efficiently transmit stimulated excitation light and stimulated emission.

Examples of such a material include plate glass such as quartz, borosilicate glass, and chemically strengthened glass, and organic polymer compounds such as PET, OPP, and polyvinyl chloride. Here, for example, borosilicate glass shows a transmittance of 80% or more in a wavelength range of 330 nm to 2.6 μm, and quartz glass shows a high transmittance even in a shorter wavelength.

As a material for forming the protective layer, a sheet glass is preferred because it has excellent moisture resistance as well as transmittance.

The thickness of the protective layer is practically 10 μm to 3 mm, and is preferably 100 μm or more in order to obtain good moisture proofness. When the thickness of the protective layer is 500 μm or more, a plate having excellent durability and durability can be obtained, which is preferable.

In the plate of the present invention, a layer having a lower refractive index than the protective layer may be provided between the phosphor layer and the protective layer. Further, a layer having a higher refractive index than the low refractive index layer may be further provided between the phosphor layer and the low refractive index layer. According to these protective layer configurations, the durability can be improved without impairing the sharpness of the image, which is preferable.

When an anti-reflection layer such as MgF ₂ is provided on the surface of the protective layer, the photostimulating light and the photostimulated light can be efficiently transmitted, and the effect of reducing the sharpness is preferably reduced.

The refractive index of the protective layer is not particularly limited, but is practically 1.4.
A range of ~ 2.0 is common.

Two or more protective layers can be provided as necessary. In particular, the constitution disclosed in Japanese Patent Application Laid-Open No. Sho 62-15500, in which two or more layers having different hygroscopic properties are combined, is preferable because of its high moisture-proof property.

In the plate of the present invention, the protective layer can also serve as a support. In that case, the support referred to in the present invention may not substantially exhibit the function of supporting the phosphor layer.

〔The invention's effect〕

 The following effects can be obtained by implementing the present invention.

(1) Since the image is read from the radiation exposure side of the radiation image conversion plate, an image with high sensitivity, high contrast, and high sharpness can be recorded. Further, the range of choice of the support is widened (a material having high radiation absorption can be used).

(2) The excitation / read / erase unit with a complicated mechanism is integrated, and during reading, the plate is temporarily fixed and the unit is moved, so that high-quality data is always obtained.
In addition, the apparatus can be made compact.

(3) Since the movement of the plate is relatively simple, the size of the apparatus can be reduced, and damage during movement and reading of the plate is small.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a radiation image conversion method using the apparatus of the present invention. 11: Radiation generator, 12: Subject 13: Radiation image conversion plate (13 'when reading) 13a: Phosphor surface, 14: Excitation excitation light source 15: Photoelectric conversion device, 16: Radiation image Reproduction device 17: Radiation image display device, 18: Filter FIGS. 2a, 2b, and 3 are configuration diagrams (cross-sectional views) showing one embodiment of the radiation image reading device of the present invention. DESCRIPTION OF SYMBOLS 1 ... X-ray generator, 2 ... Subject 3 ... Radiation image reading device 4 ... Radiation image conversion plate 5 ... Excitation / read / erase unit Fig. 4 shows the movement of the radiation image conversion plate in the present invention by rotation. FIG. 4 ... Plate at the time of radiography 4 '... Plate at the time of reading (hereinafter also referred to as FIGS. 5 to 8) FIG.
It is a lineblock diagram applied to line photography. 2 subject 3 imaging stand 4 radiation image conversion plate 5 excitation / read / erase unit 6 anti-vibration member FIG. 6 is a schematic view of a plate or a means for transporting a plate holding means. is there. P indicates a piston, G indicates a gear, and C indicates a cam. FIG. 7 is a sectional view of a mechanism portion in which an excitation / read / erase unit is movably provided. 4 ... radiation image conversion plate, 5 ... device body 7 ... scanner, 8 ... light collector, 8a ... light collection end face 9 ... filter, 10 ... photomultiplier 21 ... frame, 22 ... Panel transport member 25… Motor, 26… Male thread rod 27… Guide rod 30… Excitation / read / erase unit 31… Movable plate, 32… Condenser lens 33… Erase lamp, 34… Reflector 35 shutter shutter 36 light blocking means 71 72 73 73 mirror 80 scanning line 81 excitation light FIG. 8 is a schematic diagram when an optical fiber is applied to an excitation / read / erase unit. is there. 1 Laser 2 Excitation head (fiber) 3 Front plate 4 Radiation image conversion plate 5 Photomultiplier 6 Reading head (fiber)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-236886 (JP, A) JP-A-59-84637 (JP, A) JP-A-64-18361 (JP, A) JP-A-63-1986 314960 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) G03B 42/02

Claims (2)

(57) [Claims] 1. A radiation image conversion plate having a stimulable phosphor layer is irradiated with radiation to accumulate and record radiation image information. After the recording, the plate is scanned with excitation light to record the accumulation image. In a radiation image reading device configured to read radiation image information photoelectrically, after the irradiation, the plate is moved backward to a predetermined position while retracting while maintaining a parallel state with respect to the plate surface, Therefore, after fixing, the reading optical system is moved to perform reading, and a radiation image reading apparatus is provided. 2. A radiation image conversion plate having a stimulable phosphor layer is irradiated with radiation to accumulate and record radiation image information. After the recording, the plate is scanned with exciting light to record the accumulation image. In the radiation image reading device configured to photoelectrically read the radiation image information, after the exposure, the plate is moved to a predetermined place behind by rotating around a side on an extension of the plate surface. A radiation image reading apparatus, wherein the reading is performed by moving the reading optical system after fixing the image.