JPH0493831A - Radiograph information reader - Google Patents

Abstract

PURPOSE:To reduce flare and to accurately read image information by specifying the difference of a refractive index between an optical guide and a filter, and an adhesive layer. CONSTITUTION:The difference of the refractive index between the optical guide 28 and the filter 54 for absorbing excitation light, and the adhesive layers 56 and 58 for sticking both of them is made <= 0.05. Then, the flare made incident on the optical guide 28 is not reflected on a boundary between the light emitting surface of the optical guide 28 and the adhesive layers 56 and 58, and the boundary between the filter 54 and the adhesive layers 56 and 58, but surely transmitted through the adhesive layers 56 and 58, and made incident on the filter 54 so as to be absorbed, so that the flare is not made incident on the a accumulative phosphor sheet again. Thus, the flare can be reduced, and the image information can be accurately read.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a radiation image information reading device for reading radiation image information stored and recorded on a stimulable phosphor sheet.

<Prior art> When a certain type of phosphor is irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and after this, It is known that when a phosphor is irradiated with excitation light such as visible light, it exhibits stimulated luminescence depending on the accumulated energy. fluorophore).

Using this stimulable phosphor, radiation image information of a subject such as a human body is recorded on a sheet having a layer of stimulable phosphor (hereinafter referred to as a phosphor sheet), and this phosphor sheet is used to emit laser light. The stimulated luminescent light is scanned two-dimensionally with excitation light to generate stimulated luminescent light, and this stimulated luminescent light is read photoelectrically to obtain an image signal, and based on this image signal, a recording material such as a photographic light-sensitive material, The applicant has proposed a radiation image information recording and reproducing system that outputs a radiation image of a subject as a visible image on a display device such as a CRT (Japanese Patent Laid-Open No. 55-1
2429, 56-11395, etc.).

In such a radiation image information recording and reproducing system,
Conventionally, phosphor sheets have been read using various radiation image information reading devices as described below.

In a radiation image information reading device (hereinafter referred to as a reading device), excitation light of a constant intensity emitted from an excitation light source such as a 6-Ne laser is deflected in the main scanning direction by an optical deflector such as a galvanometer mirror. It is reflected and deflected, and irradiates the phosphor sheet through various optical elements such as an fθ lens.

This phosphor sheet is conveyed in a sub-scanning direction substantially perpendicular to the previous main-scanning direction by a conveying means such as a belt conveyor or two rollers.

Therefore, the excitation light deflected in the main scanning direction can two-dimensionally scan the entire surface of this phosphor sheet.

Stimulated luminescence light corresponding to the radiation image information accumulated and recorded there is generated from the part of the phosphor sheet that is irradiated with the excitation light.

This stimulated luminescence light is directly incident on the incident surface of the light guide, or is reflected by a condensing mirror disposed opposite to this incident surface, enters the incident surface of the light guide, is propagated by the light guide, and is excited. After passing through a filter that cuts light in the wavelength range, it enters a photomultiplier tube, where it is photoelectrically converted into an electrical signal, processed, and reproduced as a visible image on a CRT or photosensitive material, or as a visible image on a CRT or photosensitive material. Recorded and stored on a recording medium.

Incidentally, in such a reading device, one of the problems that reduces the accuracy of image reading is the problem of flare (stray light). There are various flares such as intruding light from the outside, but the most problematic flare in reading devices (radiation image information reading devices) is phosphor sheet A as shown by the dashed line in Fig. 9. incident on and reflected
This is scattered excitation light.

A portion of such flare is reflected and scattered by the condensing mirror 106 or the incident surface 104 of the light guide 102 and is directly reflected or scattered by the light guide 102, such as flares 100a and 100b.
The light is reflected and scattered by the incident surface 104 and the condensing mirror 106, or, like the flare 100C, it travels in a direction substantially opposite to the excitation light and is reflected and scattered by the housing of the scanning optical system, etc., and then enters the phosphor sheet A again. to generate stimulated luminescence light.

Further, a part of the flare that enters the light guide 102 from the entrance surface 104 is reflected by the adhesive layer on the exit surface of the light guide 102, exits from the entrance surface 104, and enters the phosphor sheet A again.

FIG. 10 shows a schematic side view of the condensing system of such a reading device.

The light guide 102 is made of a material such as acrylic. A color filter 124 for absorbing excitation light is disposed on the output surface 120 through a light-transmitting adhesive layer 122, and a photoelectron intensifier, which is a photodetector, is arranged through a light-transmitting adhesive layer 126. Doubler tube 128 and color filter 124 are bonded together.

Here, since the refractive index of the light guide 102 (the material for forming it) and the filter 124 is significantly different from that of the adhesive layer 122, the light enters the light guide 102 from the incident surface 104 and is propagated together with the stimulated luminescence light. A portion of the flare is reflected at the interface between the adhesive layer 122 and the exit surface 120 or the interface between the adhesive layer 122 and the filter 124, propagates in the opposite direction to the direction in which it entered, and exits from the entrance surface 104. Then, the light enters the phosphor sheet A again to generate stimulated luminescent light.

The stimulated luminescence light due to such flare enters the light guide 102 in the same way as the stimulated luminescence light emitted by the excitation light I-, is propagated, and is read as image information.

However, it is extremely rare for the flare to be incident on the same position as the excitation light irradiation position, that is, the image reading position 108, and therefore, most of the stimulated luminescence light due to the flare is at a position different from the position where it should be originally read. Because it is photostimulated light,
As a result, the contrast of the read image is reduced, which prevents accurate reading of image information. Also,
If this reduction in contrast is electrically processed, image information due to flare will also be amplified as noise, resulting in CR
When reproduced as a visible image on T or various recording materials, a good image cannot be obtained.

In order to solve these problems, the present applicant applied a dichroic coating to the reflective surface 110 of the condensing mirror 106 in Japanese Patent Laid-Open No. 60-189736, which reflects the stimulated luminescence light but does not reflect the excitation light. The reading device
Further, in Japanese Patent Application Laid-Open No. 60-189737, a reading device is further provided in which an excitation light reflection prevention curtain that does not reflect excitation light is provided on the entrance surface 104 of the light guide 102.
-65231 publication, the previous Japanese Patent Application Laid-Open No. 60-18973
6 and JP-A-60-189737, a mirror is added to the back side of the condensing mirror, and this mirror directs the excitation light transmitted through the condensing mirror to the phosphor sheet. Each of these discloses a reading device which is also used as erasing light by reflecting the light to the position where the reading is completed.

<Problems to be Solved by the Invention> According to each of the above devices, the reflecting surface 11 of the condensing mirror 106
It is possible to significantly reduce the flare that is reflected by the incident surface 104 of the light guide 102 and enters the phosphor sheet A again, and reads radiation image information with extremely high precision compared to conventional devices. be able to.

However, in each of the above devices, once the light enters the light guide 102, the output surface 120 and the filter 1
24 and the adhesive layer 122 that adheres the two, and the flare that enters the phosphor sheet A again cannot be removed, and therefore, the advent of radiation image information reading that further reduces the adverse effects of flare. is desired.

An object of the present invention is to solve the problems of the prior art described above, and to solve the problem of flare in a radiation image information reading device, in particular, after the flare is incident on the light guide, it is attached to the exit surface of the light guide and the filter, and the adhesive that bonds both. It is an object of the present invention to provide a radiation image information reading device which can greatly reduce the flare that is reflected at the interface with the agent layer and enters the phosphor sheet again, and which enables accurate reading of image information.

Means for Solving the Problems> In order to achieve the above object, a first aspect of the present invention includes a scanning optical system that scans a stimulable phosphor sheet on which radiation image information is accumulated and recorded with excitation light; a light guide having an entrance surface facing the scanning line near the main scanning line of the excitation light and propagating stimulated luminescence light emitted from the stimulable phosphor sheet by scanning of the excitation light; a photodetector that photoelectrically reads stimulated luminescence light propagated by a light guide; a filter that absorbs the excitation light and is disposed between the exit surface of the light guide and the photodetector; and the filter and an adhesive layer that adheres the output surface of the light guide.
A radiation image information reading device is provided, wherein a difference in refractive index between the light guide and the filter and the adhesive layer is 0.05 or less.

A second aspect of the present invention also includes a scanning optical system that scans a stimulable phosphor sheet on which radiographic image information is stored and recorded with excitation light, and a scanning optical system that is arranged near the main scanning line of the excitation light and facing the scanning line. a light guide having an entrance surface and propagating the stimulated luminescence light emitted from the stimulable phosphor sheet by scanning the excitation light; and photoelectrically reading the stimulated luminescence light propagated by the light guide. The present invention provides a radiation image information reading device comprising a photodetector, wherein the light guide has a wedge-shaped exit surface.

<Operation of the Invention> The radiation image information reading device according to the first aspect of the present invention has a refractive index difference of 0.05 or less between the light guide and the filter that absorbs excitation light, and the adhesive layer that adheres them together. Preferably, it has a configuration of 0.03 or less. Therefore,
The flare that enters the light guide is not reflected at the interface between the output surface of the light guide and the adhesive layer, or the interface between the filter and the adhesive layer, and is reliably transmitted through the adhesive layer and incident on the filter. Since the light is absorbed by the stimulable phosphor sheet, it does not enter the stimulable phosphor sheet again.

Further, in the radiation image information reading device according to the second aspect of the present invention, the exit surface of the light guide has a wedge-shaped shape. Therefore, even if the flare incident on the light guide is reflected at the exit surface or the interface between the filter and the adhesive layer, the angle of reflection of the flare will exceed the critical condition (total reflection condition), so the flare will accumulate again. The light does not enter the phosphor sheet.

Therefore, according to the radiation image information reading device of the present invention, it is possible to read radiation image information accurately with less reduction in contrast and noise due to flare.

<Embodiments> Hereinafter, regarding the radiation image information reading device according to the present invention,
DESCRIPTION OF THE PREFERRED EMBODIMENTS A detailed description will be given of preferred embodiments shown in the accompanying drawings.

FIG. 1 shows a schematic perspective view of an example of a radiation image information reading device to which the present invention is suitably applied.

The illustrated radiation image information reading device 10 (hereinafter referred to as the reading device 10) includes a stimulable phosphor sheet A (hereinafter referred to as the phosphor sheet A) on which radiation image information is stored and recorded.
This phosphor sheet A is scanned two-dimensionally with excitation light.
The radiation image information recorded on the phosphor sheet A is read by generating stimulated luminescence light corresponding to the image information stored and recorded on the phosphor sheet A and photoelectrically measuring the stimulated luminescence light.

In the illustrated reading device 10, a scanning optical system that deflects excitation light in the main scanning direction indicated by arrow a and scans the phosphor sheet A basically includes a laser light source 12, a galvanometer mirror 14, and an fθ lens 16. It consists of

Excitation light is emitted from a laser light source 12 and enters a galvanometer mirror 14 . As the laser light source 12, depending on the stimulable phosphor applied to the phosphor sheet A, He
Various excitation light sources can be used, such as a -Ne laser.

The excitation light incident on the galvanometer mirror 14 is reflected and deflected in the main scanning direction indicated by arrow a, enters the fθ lens 16, and its focus is adjusted so that it converges on the scanning line, and irradiates the phosphor sheet A. do. Note that the optical deflector applied to the present invention is the galvanometer mirror 14 in the illustrated example.
The present invention is not limited to, and any known optical deflector such as a polygon mirror resonant scanner can be used.

Further, it goes without saying that such an excitation light scanning optical system may be provided with various optical elements such as various surface tilt correction optical systems and mirrors for changing the optical path, as necessary.

On the other hand, the phosphor sheet A is placed on a belt conveyor composed of an endless belt 20 and rollers 22 and 24 that stretch it. The phosphor sheet A is conveyed by this belt conveyor in a sub-scanning direction (direction indicated by the arrow A) that is substantially orthogonal to the main scanning direction (direction indicated by the arrow a).
As a result, the entire surface of the phosphor sheet A is two-dimensionally scanned by the excitation light deflected in the main scanning direction.

Stimulated luminescence light is emitted from the position of the phosphor sheet A that is irradiated with the excitation light in accordance with the radiation image information stored and recorded there.

This stimulated luminescence light is reflected directly by the light guide 28 disposed so that its incident surface 26 faces the scanning line, or is reflected by the condensing mirror 30 disposed facing near the scanning line. 26, enters the light guide 28, is propagated, is photoelectrically read by a photomultiplier tube 32, and the result is sent to an image processing device 34.

Here, in the conventional reading device (radiation image information reading device), the excitation light (hereinafter referred to as flare) that is incident on the phosphor sheet A and reflected and scattered is returned to the phosphor sheet A.
As mentioned above, there is a problem in that the light enters the image, causes stimulated luminescence, and this is read in the same way as the stimulated luminescent light at a predetermined image reading position.

On the other hand, in the reading device 10 of the present invention, in the first aspect, the difference in refractive index between the light guide 28 and the filter that absorbs excitation light, and the adhesive layer that adheres both is zero.
．． 05 or less, and in the second aspect, by making the shape of the exit surface of the light guide 28 wedge-shaped, the flare that is generated, especially the flare that is incident on the light guide 28, is caused to overlap the exit surface and the above-mentioned. This prevents the light from being reflected at the interface with the adhesive layer and entering the phosphor sheet A again.

Furthermore, in the illustrated apparatus, as a more preferable aspect, in order to more suitably reduce the adverse effects of other flares such as flare reflected by the focusing mirror 3o and the entrance surface 26, the reflection of the focusing mirror 30 is The surface is configured, for example, by dichroic coating, etc., so that the excitation light passes through and stimulated luminescence light is reflected, and the entrance surface 26 of the light guide 28 is configured to reduce the reflectance of the excitation light.

FIG. 2 shows a schematic perspective view of a preferred example of a condensing system when the reading device 1o shown in FIG. 1 applies the first aspect of the present invention.

The light guide 28 is made of light-transmitting acrylic or the like, and is made by processing a plate-shaped light-transmitting resin by heating or the like so that the incident surface 26 corresponds to the scanning line, and That is, it is rounded to match the shape of the light-receiving surface of the photomultiplier tube 52 as it goes toward the exit surface 50a. Incidentally, such a light guide is described in detail in Japanese Patent Application Laid-Open No. 55-87970 by the present applicant.

A filter 54 for absorbing excitation light incident on the light guide 28 is bonded to the output surface 50a of the light guide 28 via an adhesive layer 56, and the photomultiplier tube 32 has its light receiving surface bonded. It is adhered to the filter 54 via the agent layer 58.

For the filter 54, a filter material that absorbs excitation light may be appropriately selected depending on the excitation light and stimulated emission light of the phosphor sheet A. Specifically, for example, if the wavelength of the excitation light is 6.
33 nm, and when the wavelength of stimulated luminescence light is 400 to 390 nm, B410, B590 (both!, m HOY A m
Color filters such as those manufactured by Manufacturer Co., Ltd.) are suitably applied. Further, the photomultiplier tube 32 is not particularly limited (any known type can be used).

In such a first aspect of the present invention, the light guide 2
8 and filter 54, and the adhesive layer 56, the difference in refractive index is 0.05 or less, preferably 0.03 or less. For example, an acrylic material with a refractive index of n:=l and 492 is used as the light guide 28,
Furthermore, when a color filter with a refractive index n=1.524 (for example, B590 manufactured by HOYA@) is used as the filter 54, the adhesive layer 56 has a refractive index n=1.474 to 1.474.
542 is applied.

With this configuration, the flare that enters the light guide 28 is not reflected at the exit surface 50a of the light guide 28 or the interface between the filter 54 and the adhesive layer 56 (most flares Since the light enters the filter 54 and is absorbed, the light does not enter the phosphor sheet A again and cause stimulated luminescence.

The adhesive layer 56 to be applied satisfies the above conditions,
Any of the various known light-transmitting adhesives capable of bonding the two can be used as long as it does not interfere with the incidence of the stimulated luminescent light into the photomultiplier tube 32. As the light guide 28, the refractive index n=1. '492 acrylic is applied, and the refractive index n is used as the filter 54.
=1.524 color filter (HOYAIm B590)
When using, a U■ curing adhesive (3080 manufactured by ThreeBond ■) with n = 1.4999 may be used.

On the other hand, in a second aspect of the present invention, the output surface of the light guide 28 has a wedge-shaped shape.

Here, the second aspect of the present invention has basically the same configuration as the first aspect described above, except that the shape of the exit surface of the light guide 28 is different, and there is no limitation on the refractive index of the adhesive layer 56. Therefore, the same members will be given the same numbers and detailed explanations will be omitted. Regarding the adhesive layer 56 applied to the second aspect of the present invention, it is possible to bond the light guide 28 and the filter 54 without interfering with the incidence of stimulated luminescence light into the photomultiplier tube 32. Various known light-transmitting adhesives can be used.

FIG. 3 is a schematic partial cross-sectional view in the sub-scanning conveyance direction (direction indicated by the arrow) of a preferred embodiment of the exit surface 51 of the light guide 29 in the second aspect of the present invention, and FIG. A partially enlarged view of the tip portion of 51 is shown. Note that this light guide 29 is also formed by processing a single plate-shaped light-transmitting resin by heating or the like, similar to the light guide 28 described above.

In the second aspect of the present invention, the end face of the output surface 51 of the light guide 29 has a wedge shape as shown in FIG. 54 is bonded.

By making the exit surface 51 of the light guide 29 into such a shape, as shown in FIG.
Even if the flare is reflected at the interface between the light guide and the adhesive layer (not shown), the progress of the reflected flare can be made to exceed the critical condition (total reflection condition) of the light guide 29.
The light exits from the side wall 29a of the light guide 29 while being propagated in the direction of the entrance surface 26, and does not exit from the entrance surface 26 and enter the phosphor sheet A again.

As shown in FIG. 4, when the angle of the exit surface 51 of the light guide 29 is α, the light ( The angle θ1 at which the flare (flare) enters the side wall 29a of the light guide 29 is:
It is given by the following formula.

θ l : β −2α On the other hand, the angle (θ) condition (critical condition) under which the light incident on the side wall 29a does not undergo total reflection is expressed as follows.

Ten. 〈θ〈θ0 However, θ. =s i n−' (nz /n+)n,
refractive index n2 of the material forming the light guide 29: refractive index of the outside of the light guide 29 Therefore, in order to emit the light reflected by the exit surface 51 to the outside from the side wall 29a, the following conditions may be satisfied. .

−θ0〈β−2α×θ. Equation (2) Incidentally, the distribution of the incident angle β of light that is incident on the light guide 29 and propagated through repeated total reflections is considered to be as shown in FIG.

Here, of the light reflected by the output surface 51, the fifth
The angle α of the output surface 51 for outputting the light indicated by the shaded area from the side wall 29a is as follows from the above equation (2).

β=θ. In this case, 0〈α〈θ. Formula ■β=π/2
In this case, (π/2−θ.)/2 × α〈 (π/2+θ.)72
Equation (2) The light in the shaded area (θ.×β<π/2) reflected on the exit surface 51 is made to exceed the critical condition, and all of the light is reflected on the side wall 2.
In order to emit light from 9a, it is necessary to satisfy both the conditions of the above equations (1) and (2), and in this case, the angle α of the light emitting surface 51 is expressed by the following equation.

(π/2−θ.)/2〈α〈θ. Formula (2) Therefore, for example, if the refractive index n+ of the light guide 29 is 1.492, the angle a of the exit surface 51 can be set from 24° to 42° from the above formula (2).
Then, the flare reflected on the exit surface 51 can be emitted from the side surface 29a of the light guide 29, and this flare can be prevented from entering the phosphor sheet A again and generating stimulated luminescence light. In addition, as the angle α approaches 42°, the incident angle β outside the shaded area in Figure 5 decreases.
The flare that is incident on the light guide 29 and reflected by the exit surface 51 can also be emitted to the outside through the side wall 29a.

In the second aspect of the present invention, the angle α of the exit surface 51 may be appropriately set according to the refractive index of the light guide 29 to an I/X angle at which the flare does not enter the phosphor sheet A again. No limitation 1° For example, if the refractive index of the light guide 29 is n
= 1.492, as mentioned above, α = 24°~, 42
If it is set to °, suitable results can be obtained.

In addition, in the example shown in FIG. 3, the end surface corresponding to the output surface 51 of the resin plate forming the light guide 29 is shaped into a wedge shape, so that the output surface 51 is wedge-shaped.
The present invention is not limited to this, but as shown in FIG.
It may be arranged with

The first and second aspects of the present invention described above are examples in which the light guide disclosed in JP-A-55-87970 is applied as a light guide, but the present invention is not limited to this. The light guide 70 shown in FIG.
A sheet-like light guide material is cut into strips in a direction perpendicular to the portion corresponding to the incident surface 72, and the strips are overlapped in the thickness direction of the light guide material to emit light. Surface 74
The present invention is also suitably applied to the light guide disclosed in Japanese Patent Application Laid-Open No. 63-236025 by the present applicant.

In addition, when applying this light guide 70 to the second aspect of the present invention, the shape of this exit surface 74 is such that the end face of the strip portion of the light guiding material (rust), as shown in FIG. (Also, as in the example shown in FIG. 6 described above, a wedge shape may be continuously formed in a strip portion.)

By configuring the reading device 10 of the present invention as described above, in the first aspect, the flare that is incident on the light guide and reflected at the exit surface or the interface between the filter and the adhesive layer is returned to the phosphor sheet. In addition, in the second embodiment, even if the flare is reflected at this interface, the reflection angle exceeds the critical condition, so it will be emitted outside the light guide, and the light guide The flare that has entered the phosphor sheet A will not enter the phosphor sheet A again.

Preferably, the condensing mirror 3 is
The 00 reflecting surface 36 is provided with a dichroic coating or the like that transmits and absorbs the excitation light and reflects the stimulated luminescence light, and the incident surface 26 of the light guide 28 etc. is configured to reduce the reflectance of the excitation light. Other flares, such as flares reflected by the condensing mirror 30 and the incident surface 26, can be suitably prevented from entering the phosphor sheet A, and accurate radiation images can be obtained with very little adverse effect from flares. It becomes possible to read information.

In this way, the stimulated luminescence light that enters from the entrance surface 26 of the light guide 28 is propagated upward while repeating total reflection within the light guide 28, and the excitation light that enters together with it is cut by a color filter (not shown) to generate photoelectrons. The light enters the multiplier tube 32 and is read photoelectrically. The electrical image signal obtained here has very little stimulated luminescence due to flare as described above, and is therefore a good image signal with high contrast and little noise.

This electrical signal is sent to the image processing device 34 and processed, and is reproduced as a visible image on a display such as a CRT 40 or stored in an image recording medium 42 or the like.

Although the radiation image information reading device according to the present invention has been described in detail above, the present invention is not limited thereto (various changes and improvements may be made without departing from the gist of the present invention). Of course, it is also good.

<Effects of the Invention> As explained in detail above, according to the radiation image information reading device of the first aspect of the present invention having the predetermined configuration,
The flare incident on the light guide is not reflected at the interface between the exit surface of the light guide, the filter for absorbing excitation light, and the adhesive layer that adheres the two. It passes through and is absorbed by the filter, so
The light does not enter the stimulable phosphor sheet again.

Further, according to the radiation image information reading device of the second aspect of the present invention, even when the flare incident on the light guide is reflected at the exit surface or the interface between the filter and the adhesive layer, the reflected flare Since the reflection angle can be made to exceed the critical condition (total reflection condition), the flare will not again enter the stimulable phosphor sheet.

Therefore, according to the radiation image information reading device of the present invention,
Accurate radiation image information can be read with less noise and reduced contrast due to flare.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing an example of a radiation image information reading device to which the present invention is suitably applied. FIG. 2 is a schematic perspective view showing an example of a condensing system applied to the first aspect of the present invention. FIG. 3 is a schematic cross-sectional view showing an example of the exit surface of the light guide applied to the second aspect of the present invention. FIG. 4 is a partially enlarged view of FIG. 3. FIG. 5 is a graph showing an example of the distribution of incident angles of light incident on the light guide. FIG. 6 is a schematic side view showing another example of the vicinity of the exit surface of the light guide applied to the second aspect of the present invention. FIG. 7 is a schematic perspective view showing another example of the light guide applied to the present invention. FIG. 8 is a schematic perspective view of an example exit surface when the light guide shown in FIG. 7 is applied to the second aspect of the present invention. FIG. 9 is a diagram conceptually showing the vicinity of the main scanning line of a conventional radiation image information reading device. FIG. 10 is a schematic side view of a condensing system applied to a conventional radiation image information reading device. Explanation of symbols 10... Radiation image information reading device, 12... Laser light source, 14... Galvanometer mirror 16... fθ lens, 20... Endless belt, 22. 24... Roller, 26. 72,104,120--Incidence plane, 28.29
, 60, 70° 102... Light guide, 30.106... Concentrating mirror 32.128... Photomultiplier tube, 34... Image processing device, 40... CRT. 42... Image recording medium, 50 51.62.74... Output surface, 54.124.
...filter, 56.57,58,64,122゜126...adhesive layer, 110...reflecting surface, A...stimulable phosphor sheet, L...excitation light

Claims (2)

[Claims] (1) a scanning optical system that scans a stimulable phosphor sheet on which radiation image information is stored and recorded with excitation light; and an entrance surface that is located near the main scanning line of the excitation light and faces the scanning line; a light guide that propagates the stimulated luminescence light emitted from the stimulable phosphor sheet by scanning the excitation light; a photodetector that photoelectrically reads the stimulated luminescence light propagated by the light guide; and the light guide. a filter that absorbs the excitation light and is disposed between an output surface of the light guide and the photodetector; an adhesive layer that adheres the filter and the output surface of the light guide; A radiation image information reading device characterized in that a difference in refractive index between the filter and the adhesive layer is 0.05 or less. (2) a scanning optical system that scans a stimulable phosphor sheet on which radiation image information is stored and recorded with excitation light; and an entrance surface that is located near the main scanning line of the excitation light and faces the scanning line; A light guide that propagates stimulated luminescence light emitted from the stimulable phosphor sheet by scanning the excitation light, and a photodetector that photoelectrically reads the stimulated luminescence light propagated by the light guide. A radiation image information reading device, wherein the light guide has a wedge-shaped exit surface.