JPS6199140A - Traveling medical examination car - Google Patents

Abstract

PURPOSE:To take many pictures continuously by mounting a radiation picture information recorder/reader constituted so that accumulative fluorescent sheets are circulated in photographing, reading and erasing parts on a traveling medical examination car. CONSTITUTION:Each accumulative fluorescent sheet is supplied from a stack case 11 or 15' to a photographing part 10 and the picture information of a subject 1 is recorded and then carried to a reading part 20 through a carrying belt 14. Then, the read sheet 2 is carried by a carrying belt 32, a guide plate 4 and belt groups 33A-33E and delivered into a pair of erasing units 41, 42. The units 41, 42 are alternately used by a pair of distributing belts 34 to obtain a long erasing time by a short belt. The erased sheet 2 is distributed by a distribution plate 17 and stored in the stack case 11' or 15 stacking sheets.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile medical examination type that carries a radiotafjA imaging device and moves to various locations to perform medical examinations.

Certain fluorophores emit radiation (X-rays, alpha rays, beta rays).

When irradiated with gamma rays, electron beams, ultraviolet rays, etc., part of the energy of this radiation is accumulated in the phosphor, and when the phosphor is subsequently irradiated with excitation light such as visible light, the energy of this radiation is accumulated. The phosphor exhibits stimulated luminescence depending on the energy. A phosphor exhibiting such properties is called a stimulable phosphor.

Using this stimulable phosphor, radiation image information of a subject such as a human body is stored and recorded on a sheet of stimulable phosphor, and this is scanned with excitation light to cause stimulated luminescence. A radiation image information recording and reproducing method has been proposed in which light is read photoelectrically to obtain an image signal, and this image signal is processed to obtain a radiation image of a subject that is suitable for diagnosis. (For example, JP-A-55-12429, JP-A-56-11395, JP-A-55
-163472, 56-104645, 55
-116340, etc.) In this method, the final image may be reproduced as a hard copy or
It may also be reproduced on T.

In any case, in such a radiographic image information recording and reproducing method, a stimulable phosphor sheet (strictly speaking, this can take various forms such as a panel or a drum, but it is generally called (referred to as "sheet")
This stimulable phosphor sheet does not ultimately record image information, but temporarily carries image information in order to provide an image to the final recording medium as described above, so this stimulable phosphor sheet cannot be used repeatedly. It may also be used repeatedly, and it is extremely economical to use it repeatedly in this way.

In order to reuse the stimulable phosphor sheet as described above, the radiation energy accumulated in the stimulable phosphor sheet after the stimulated luminescence light is read is used, for example, in Japanese Patent Laid-Open No. 56-113
The stimulable phosphor sheet may be emitted to erase the radiation image by a method such as that shown in No. 92, No. 56i2599, and the stimulable phosphor sheet may be used again for recording radiation images. In the actual device, the stimulable phosphor sheet after the reading is completed is supplied to an image erasing device by a conveying means such as a belt conveyor, and the stimulable phosphor sheet from which the radiation image has been erased is further processed as described above. It is also possible to save labor by sending the image back to the image recording unit using a suitable conveyance means.

This method of recording and reproducing radiation image information using a stimulable phosphor is particularly effective when used for medical diagnosis. In other words, this method can obtain radiographic image information suitable for the diagnostic structure by applying various signal processing to electrical signals, and by adjusting the reading gain of the photodetector during charge conversion. Radiation exposure using conventional silver salt emulsions has made it possible to significantly reduce radiation exposure.
It has significant advantages over single-line photography.

Therefore, it is desirable that diagnosis using this radiation image information recording and reproducing method be carried out not only in medical institutions such as hospitals, but also in various locations using mobile examination types loaded with equipment, such as conventional X-ray indirect radiography vehicles. ing. However, in this method of recording and reproducing one radiographic image information, one large stimulable phosphor sheet is basically used to record one radiographic image information, which makes the radiographic work complicated, and in addition, mobile examinations are required. In order to go on a business trip and examine patients, a large number of these large sheets must be loaded onto a mobile examination type and carried around, which naturally limits the examination processing capacity of the mobile examination type.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a mobile medical examination type in which the medical examination processing capacity by the radiation image information recording and reproducing method is significantly improved, and furthermore, radiography work is easy. Furthermore, the object of the present invention is to provide a mobile medical examination type that has improved examination processing capacity as described above and also makes it possible to obtain diagnostic results directly at the examination site.

The mobile medical examination type of the present invention includes a circulation conveyance means for conveying at least one stimulable phosphor sheet capable of accumulating and recording radiographic images along a predetermined circulation path, and a circulation conveyance means for conveying at least one stimulable phosphor sheet capable of accumulating and recording radiographic images; an image recording green section that accumulates and records a radiographic image of the subject on this sheet by irradiating radiation through the subject; 1) a sheet that is located in the circulation path q and on which the radiographic image is accumulated and recorded in the image recording section; an image reading unit having an excitation light source that emits excitation light for scanning, and a photoelectric reading unit that obtains an image signal by reading stimulated luminescence light emitted from the sheet scanned by the excitation light;
and further comprising an erasing section in the circulation path that discharges residual radiation energy on the sheet prior to recording an image on the sheet after the image has been read in the image reading section. The characteristic radiation image information recording/reading device is mounted on a vehicle such as a bus.

In the radiation image information recording/reading device having the above structure, since the recording medium is used cyclically while undergoing erasure of the radiation image in the mobile medical examination vehicle, one stimulable phosphor sheet is handled for one image. There is no need, and the screening throughput can be increased virtually unlimitedly.

The image signal obtained by the reading means is transmitted in real time to a reproduction device (for example, a hard copy production device or a display device such as a CRT) installed in a hospital etc. using a telephone line or wireless communication, and a specialist can perform the reproduction. It is also possible to observe the images and report the diagnosis results in a mobile examination format. It is also of course possible to transmit the image signal to a hospital, etc., record a portion of this image signal on a recording medium such as a magnetic tape, magnetic disk, or optical disk, and later diagnose the reproduced image using 19. be. By transmitting image signals outside the examination vehicle and recording or reproducing the image signals at a hospital or the like in this manner, the number of devices loaded on a mobile examination vehicle can be reduced.

However, when using a car with a large loading capacity, a recording device using the recording medium as described above,
Small playback f! Of course, it is also possible to load the equipment in a medical examination type. If the reproducing device is loaded into a medical examination type vehicle and a specialist is brought along, it is naturally possible to immediately notify the examinee of the diagnosis results at the radiation examination site. Furthermore, since the recording medium described above can be made compact and record an extremely large amount of information, even if an image signal recording device using this type of recording medium is installed in a medical examination type, it will not be possible to use the large-sized storage medium as described above. Compared to the case where radiation images are stored and recorded on each stimulable phosphor sheet (like the size of a conventional X-ray film cassette) and then taken to a medical institution, the medical examination processing capacity is lower compared to the weight of the loading device. is significantly increased.

In the present invention, a storage fluorophore refers to radiation (X-rays, α
rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.),
It has the property of accumulating a portion of this radiation energy inside and then emitting stimulated luminescence light in an amount corresponding to the accumulated energy when it is irradiated with excitation light such as visible light.

In the present invention, the stimulable phosphor sheet refers to a sheet-like recording medium made of the above-mentioned stimulable phosphor, and generally includes a support and a stimulable phosphor layer laminated on the support. It consists of The stimulable phosphor layer is formed by dispersing the stimulable phosphor in a suitable binder, and if the stimulable phosphor layer is self-supporting, it will itself contain the stimulable phosphor. It can be used as a light sheet.

In the present invention, in order to improve the S/N ratio, it is preferable that the wavelength range of excitation light and the wavelength range of stimulated luminescent light do not overlap ffl, and the excitation light source and storage properties are adjusted to satisfy such a relationship. Preferably, a phosphor is selected. Specifically, it is desirable that the wavelength of the excitation light be 450 to 900 nIl and the wavelength of the zeta-stimulated emission light be 300 to 500 nIl.

In this way, it emits stimulated luminescence light of 300 to 500 nm,
Examples of WM phosphors that can be preferably used in the present invention include ZnS:Cu, Pb, BaO.
:Eu [however, 0.8≦X≦12 o], and M O・x S i 02 : A
[However, M2+ is Mg, c a 1s r % Z
n s Cdl or Ba, A is Ce, Tbl
EuXTm1Pb, King, 1.3i, or Mn;
X is a phosphor represented by a composition formula such as 0゜5≦X≦2.5, as described in JP-A-55-12143 (Bat-, x77, Mg, Ca, )FX: a
Eu [However, X is at least one of C and 3r
A phosphor represented by the composition formula of
LnOX:XA described in Publication No. 5-12144
[However, l-n is at least one of La5Y, Gd, and LLI, X is at least one of CJljr15 and [3r, A is at least one of Ce' and Tb, and X is , Q<x<0.1];
At least one of Ca, 5rSZn, and Cd(7), X is C, 3r, and at least one of I, A is Eu, Tb, Ce, Tm, DVlPr, Ho,
A phosphor comprising at least one of Nd, Yb1 and Er, and represented by the composition formula 1 where X is 0≦X≦0.6 and y is O≦y≦0.2, JP-A-Sho It is described in No. 55-160078 and L
Im here M FX-xA
:yLn [where M is Ba, Ca, Sr, MQ, Z
At least one of n, J5 and Cd, A is BeO
lMgc, CaO1SrO, sao, zno, ALz
03, Yz O3, Laz 03, Inz 03
, S ioz , TLOz, ZrO2, GeO2,5n
Oz, Nb2O51Ta205, and T h O2
At least one of LnLLEu, Tb, Ce,
At least one of Tm, Dy, Pr, HOINd, Yb, Er, Sm, and Gd, X is at least one of C4, Br, and I, and X and y are each 5X104≦X≦0.5 , and O<y≦0.2
A phosphor represented by the composition formula: JP-A-56-1
Described in Publication No. 16777! There is (Bat-x, M,)F2 ・aBaXz:
yEu, zA [where Mx is at least one of beryllium, magnesium, calcium, strontium, zinc, and cadmium, X is at least one of chlorine, bromine, and iodine, and A is at least one of zirconium and scandium. It is a kind of alx
ly, and 2 are each 0.5≦a≦1.25.0≦
X≦1.10≦y≦2X10-1, and Q<z≦1
A phosphor represented by the compositional formula of (Ba1-%, MX) Fz ・aBaXz :
yEu.

zB[However, M″L is at least one of beryllium, magnesium, calcium, strontium, zinc, and cadmium, X is at least one of chlorine, bromine, and iodine, and alx, yl, and Z are each 0 .5≦a≦1.25, 0≦X≦1.10≦y
A phosphor represented by the composition formula 1 where ≦2×10°1 and Q<z≦10°l is described in JP-A-57-23675 (Ba
t-%+MX) F2 ・aBaXz: ”y'E
u.

ZA [However, MTL is at least one of beryllium, magnesium, calcium, strontium, zinc, and cadmium, X is at least one of chlorine, bromine, and iodine, and A is at least one of arsenic and silicon. -Li, a, X.

y, and 2 are respectively 0.5≦a≦1.25, b O≦X≦1.1o ≦y 2x10-', ffi.

・(A phosphor represented by the composition formula 1 where 2≦5X10'')
X ;x Ce [Tata 5, MX4 Yo Pr, Nd
.

Pm, Sm, Eu%Tb, oy, H
is at least one trivalent metal selected from the group consisting of a, Er, Tm, Yb, and B1, and X is C
Q, and/or 3r, and x is Q < Iru Ba
t-x M, /, Lyyz FX: YELL” [
However, M represents at least one alkali metal selected from the group consisting of L 11Na, Rb, and C5; L is 3c, Y, (-a, C'eSPr.

Nd, Pm, Sm, Gd, Tb, Dy1l-1o, Er
, Tm, Yb, Lu, Afl, , Ga, In1 and T
z represents at least one trivalent metal selected from the group consisting of; X represents at least one halogen selected from the group consisting of C9J, Br, and I; and
X is 104≦X≦0.5, y is O<y≦0.1]
A phosphor represented by the composition formula, 5aF described in JP-A No. 59-27980
X-xA:yEu" [wherein, 10 ≦X≦0.1, y is O<y
≦0.1] A phosphor represented by the composition formula: BaF described in JP-A No. 59-47289
X-xA: VEu” [However, X is CQI SB
r N and! zA is at least one type of halogen selected from the group consisting of hexafluorosilicic acid, hexafluorotitanic acid, and hexafluorozirconic acid, and at least one type of halogen selected from the group consisting of monovalent or divalent metal salts of hexafluorozirconic acid. JP-A-59-1999-1 is a fired product of a compound; X is 10≦X≦0.1; 56
BaFX -xNaX' described in 479 publication
: aEu2+ [However, X and X' are at least one of C reaction, 3r1 and I, respectively, and X and a are respectively O<X≦2 and O<a≦0
．． A phosphor represented by the compositional formula of at least one alkaline earth metal selected from the group consisting of: X and X' are C9J and Br, respectively.

and at least one halogen selected from the group consisting of I; A is ■, Cr, Mn5Fe;

At least one transition metal selected from Co1 and Ni: and X is O<X≦2, y is o<y≦0.
2, and 2 are phosphors represented by the composition formula J, where 0<z≦104, as disclosed in Japanese Patent Application Laid-open No. 1982-75200 by the present applicant. , MIm is at least one alkaline earth metal selected from the group consisting of 3a, Sr, and Ca;
is at least one alkali metal selected from the group consisting of L+, Na, Rb, and C6;
'■ is at least one divalent metal selected from the group consisting of Be and M9, binary M is at least one trivalent metal selected from the group consisting of /'l, Qa, ln, and T9J, and zA is is a metal oxide; X is at least one halogen selected from the group consisting of C9i 1Br N and °I;
Br, and at least one halogen selected from the group consisting of I; and a is O≦a≦2, and b is 0
≦b≦10', C4; to≦c≦104, and a+b
+c≧10: X is Q<x≦0.5, y is o<y
≦0.2] A phosphor is described in Japanese Patent Application No. 193161/1982 and is represented by the composition formula: at least one kind of alkaline earth metal selected from the group consisting of; X and X' are at least one kind of halogen selected from the group consisting of C, 3r and f, and X≠X';
and a is a numerical value in the range of 0°1≦a≦10.0,
Examples include a phosphor represented by a compositional formula in which X is a numerical value in the range of O x ≦0.2.

Further, as disclosed in JP-A-55-163500, when the phosphor layer of a stimulable phosphor sheet prepared using the above-mentioned stimulable phosphor is colored with a pigment or dye, @The sharpness of the final image is improved, which is preferable.

By the way, the radiation image information record reading device 8 installed during the mobile medical examination according to the present invention! The i-position has the very practical advantage of being able to record images over a much wider range of radiation exposure compared to radiographic systems using conventional 811 salt photography. In other words, in stimulable phosphors, it is recognized that the amount of emitted light that is stimulated and emitted by excitation after accumulation is proportional to the amount of radiation exposure over an extremely wide range, and therefore Even if the amount of radiation exposure varies considerably, the amount of emitted light is read by the photoelectric conversion means by setting the reading gain to an appropriate value and converted into an electrical signal, and this electrical signal is used to convert the photosensitive material, etc. A radiation image that is unaffected by fluctuations in radiation exposure by outputting it as a visible image on a recording material or a display device such as a CRT! ':) You can.

Furthermore, according to this system, radiation image information accumulated and recorded on a stimulable phosphor sheet is converted into an electrical signal, then subjected to appropriate signal processing, and this electrical signal is used to produce recording materials such as photographic light-sensitive materials, CRTs, etc. By outputting the image as a visible image on a display device such as the above, it is possible to obtain a very large effect that a radiation image having excellent suitability for observation and interpretation (diagnosis) can be obtained.

In this way, in a radiation imaging system that uses a stimulable phosphor sheet, the reading gain can be set to an appropriate value to photoelectrically convert the stimulated luminescence light and output it as a visible image, so the radiation source fluctuations in the radiation exposure m due to fluctuations in the tube voltage or MAS value, fluctuations in the sensitivity of the stimulable phosphor sheet, fluctuations in the sensitivity of the photodetector, changes in the exposure amount due to subject conditions, or changes in radiation transmittance depending on the subject. Even if the energy stored in the stimulable phosphor sheet differs due to various factors, or even if the amount of radiation exposure is reduced, it is possible to obtain a radiographic image that is not affected by fluctuations in these factors. By first converting the stimulated luminescent light into an electrical signal and then applying appropriate signal processing to this electrical signal, you can obtain one radiation image and eight images suitable for diagnostic areas such as the chest and heart! Z′! ″″″′C″8・6
It is now possible to interpret images with a reading capacity of 8.18.

However, in order to eliminate the influence of fluctuations in starvation conditions or to obtain radiographic images that are highly suitable for observation and interpretation, it is necessary to change the recording state of the radiographic image information accumulated and recorded on the stimulable phosphor sheet, or the chest, Recording patterns (hereinafter referred to collectively as "accumulated recorded information") determined by the region of the subject such as the abdomen, positive methods such as simple and contrast enhancement, etc. are recorded in a visible manner for observation and interpretation. It is essential to understand the information before outputting the image, and to adjust the reading gain to an appropriate value or perform appropriate signal processing based on the accumulated recorded information thus obtained.

In addition, the resolution is n depending on the contrast of the recording pattern.
It is necessary to determine the recording scale factor so that the image data is J-sized in order to obtain radiographic images that are not suitable for observation and interpretation.

Is it possible like this? As a method of grasping accumulated record information of radiation image information prior to outputting J2vA, Japanese Patent Application Laid-Open No. 1983-
A method disclosed in No. 50180 is known.

This method states that when the stimulable phosphor sheet is irradiated with radiation, the amount of instantaneous light emitted from the stimulable phosphor sheet is proportional to the amount of energy accumulated and recorded in the stimulable phosphor sheet. Based on the knowledge, by detecting this instantaneous emitted light, the accumulated recorded information of radiation image information is grasped, and based on this information, appropriate signal processing is performed, and 1! The aim is to obtain radiographic images with excellent suitability for image interpretation. According to this method, the reading gain is adjusted to an appropriate value,
Alternatively, since it is possible to appropriately select the recording scale factor or to not perform appropriate signal processing, it is possible to eliminate the influence of fluctuations in imaging conditions, or to obtain radio94-ray images that are highly suitable for observation and interpretation. However, since the image recording section and the image reading section are usually separated in position, a signal transmission system must be constructed between them, making the device complicated and increasing costs. The disadvantage is that it cannot be avoided.

Therefore, prior to the reading operation to obtain a visible image for observation and interpretation, the accumulated recorded information of radiation image information accumulated and recorded on the stimulable phosphor sheet is simply and accurately detected.
It is desired to reproduce radiographic images with excellent diagnostic performance based on this information.

Is this OK for observational interpretation? Reading operation to obtain J2 image (
Hereinafter, this will be referred to as "book reading." ), using excitation light with an energy lower than that of the excitation light to be irradiated in the above-mentioned main reading, grasp the accumulated record information of the radiation image information accumulated and recorded in advance on the stimulable phosphor sheet. A reading operation (hereinafter referred to as "pre-reading") is performed to grasp the accumulated recorded information of radiation image information, and then a main reading is performed to appropriately adjust the reading gain based on the pre-reading information. This can be achieved by applying appropriate signal processing.

A preferred embodiment of the present invention is characterized by comprising a means for pre-reading, and further comprising a control means for setting reading conditions and/or image processing conditions for main reading based on the accumulated record information obtained by pre-reading. It is something to do.

In the present invention, the energy of excitation light refers to the effective energy of excitation light received per unit area of the stimulable phosphor sheet.

In the present invention, it is sufficient that the energy of the excitation light to be applied to the stimulable phosphor sheet during pre-reading is lower than the energy of the excitation light during main reading. The closer the ratio of the excitation light energy of the pre-reading to that of the main reading is to 1, the smaller the amount of radiation energy remaining and accumulated during the main reading, but if this ratio is less than 1, the value of the reading gain should be adjusted appropriately. It has been shown that radiological images suitable for observation and interpretation can be obtained by adjusting the However, in order to obtain radiographic images that are suitable for observation and interpretation, the radiographic image information accumulated and recorded on the stimulable phosphor sheet by pre-reading is used to select reading conditions or optimal image processing conditions. In other words, as long as the stimulated luminescence emitted from the stimulable phosphor sheet can be sufficiently detected in the above sense,
The ratio of the energy of the excitation light for pre-reading and main reading is preferably as small as possible, and is desirably 50% or less, preferably 10% or less, and more preferably 3% or less. The lower limit of this ratio is determined by the accuracy of the pre-read stimulated luminescence light detection system.

As described below, in the present invention, it is preferable that the excitation light source and photoelectric reading means for pre-reading are shared with those for main reading, but in this case, the energy of the excitation light for pre-reading is lower than the energy for main reading. Methods for reducing the amount of light include reducing the output of the laser light source, increasing the beam diameter of the laser beam, increasing the scanning speed of the laser beam, and increasing the transport speed of the stimulable phosphor sheet. A known method such as a method can be used.

According to the preferred embodiment of the present invention, the recording state of radiation image information accumulated and recorded on the stimulable phosphor sheet can be known in advance, so that a reading system having an exceptionally wide dynamic range is used. Even if the imaging conditions are changed, it is possible to obtain radiographic images that are always suitable for observation and interpretation by appropriately adjusting the reading gain based on this recorded information.

In addition, since the recording pattern of radiation image information stored and recorded on the stimulable phosphor sheet can be known in advance, signal processing according to the recording pattern can be applied to the electrical signals after reading. Alternatively, by optimizing the recording scale factor, it is possible to obtain radiographic images with excellent observation and interpretation suitability.

Furthermore, since it is possible to know in advance the recording pattern of the radiation image information stored and recorded on the stimulable phosphor sheet, it is possible to omit the actual reading for parts where the recording pattern does not exist. It becomes possible to shorten the reading time.

Furthermore, in a preferred embodiment of the present invention, the excitation light source and photoelectric reading means for pre-reading are used in common with those for main reading, so that the energy of the excitation light during pre-reading is smaller than the energy of the excitation light during main reading. An adjustment means is provided to allow the sheet to pass through the same location twice, thereby performing pre-reading and main reading. As a result, even in devices that read ahead,
The overall size can be designed to be compact.

This shared method includes a method in which the sheet is passed twice in the same direction at the same place, without returning part of the sheet after the first pass, and a reciprocating method in which the sheet is read in advance during the forward movement and the actual reading is performed during the backward movement. Two methods are possible.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic diagram showing an actual mode in which a radiographic image information recording/reading device for photographing a radiographic image of a chest or the like while a subject is standing is mounted on a car.

Honji/if! The mobile examination rate 50 of the aspect is, for example, a radiographic image information recording/reading device 7, which will be described later, in a car 60 such as a bus.
0 and an image signal recording device a80.

The imaging unit (image recording unit) is located at the height of the chest of subject 1.
10 is installed, where the accumulation case 1 in the supply position is installed.
The stimulable phosphor sheets 2 are supplied one by one from 1 or 15'. The photographing section 10 is composed of a pair of endless belts 12A and 12B that hold the seat 2 from the front and back, and an auxiliary endless belt 13 that is located below and guides the seat 2 rearward. A conveyor belt 14 is disposed to convey the sheet 2 conveyed from the photographing section 10 further toward the image reading section 20 at the rear.

In the reading section 20, a first feed belt 22 driven by a motor 21 and a second feed belt 24 driven by a motor 23 are arranged in series to feed the sheet 2 in the sub-scanning direction at a constant speed. There is. Photographing section 10 and reading section 2
0, a shutter 3 that can be freely moved to grJ is provided to prevent light as a disturbance from entering from the photographing unit 10 side during reading. The reading section 20 includes the first and second belts 22.
．． A laser light source 25 is installed above the belt 22 and a mirror 26A for scanning the output laser light 25A onto the sheet 2 on the belt 22.

Galvanometer mirror 26B, mirror 26C, mirror 2
6D is provided, and the laser beam 25A is main-scanned on the sheet 2 by the reciprocating movement of the galvanometer mirror 2G8. (Travel of laser beam 25A on sheet 2)
A condensing reflection mirror 27 is arranged along the main scanning line at the scanning position, and the stimulated luminescence light emitted from the beam (26s) irradiated with the laser beam 25A is excited and the condensing reflection mirror 27 is disposed along the main scanning line. The stimulated luminescence light reflected by the mirror 27 enters the condensing optical element 28 from the incident end surface 28A of the condensing optical element 28, and is connected to the exit end surface 28B of this element 28 while being guided through the condensing optical element 28 by total reflection. The stimulated luminescent light is received by the photomultiplier 29 and read in a charging manner. The image signal read here is recorded in the image signal/recording device 80. Any known type of image signal recording device 80 can be used, and preferably one that digitizes the signal and records it on a high-density recording medium such as a magnetic tape, magnetic disk, or optical disk. The identification number of the subject is recorded in the recording medium of the image signal recording device 80 in association with the image signal, and the subject is brought to a medical institution such as a hospital at a mobile examination rate of 50. In this medical institution, the recording medium is loaded onto a playback device to obtain a playback image on a hard copy or CRT display. The specialist makes a diagnosis based on this reproduced image and notifies each subject of the findings.

As already mentioned, instead of the image signal recording 80, a transmission device for transmitting electrical image signals to a remote location by, for example, a telephone line or wirelessly is mounted on the automobile 60, and the transmission device is installed in a hospital or the like far from the radiation imaging site. record image signals,
Alternatively, a reproduced image may be immediately obtained from this image signal and the diagnosis result may be transmitted back to the mobile examination rate 50. Furthermore, a small reproducing device such as a CRT display device may be loaded onto the mobile medical examination rate 50 so that the reproduced image can be immediately observed at the radiography site.

A feed belt 32 driven by a motor 31 is disposed downstream of the reading unit 20, and further above (downstream) there are endless belt groups 33A to 33E that clamp the sheet 2. A pair of belts 34 for distributing 2 in two directions is provided so as to be swingable in a variable conveying direction. The rear end of the feed belt 32 and the belt group 33
A guide plate 4 for guiding the sheet 2 from the former to the latter is arranged between the lower ends of A to 33E.

An erasing section 40 consisting of a pair of erasing units 41.42 stacked one above the other is installed in front (downstream) of the pair of belts 34 for distributing the portion, and each erasing unit 41.4
A guide plate 5.6 is disposed between the entrance of the belt 2 and the belt pair 34. The erasing units 41 and 42 each consist of transparent endless belts 41A and 42A, and a large number of fluorescent lamp groups 41B and 423 arranged therein. In the erasing section 40, it takes a long time to erase, and in order to erase for a long time in a compact device, the speed of the feed belt must be set closer to the speed of the upstream feed belt. For this reason, in the erasing section 40, the pair of endless belts 41A and 42A are alternately switched and their respective feed speeds are significantly lowered to obtain a long erasing time with a short belt. At the exits of the erasing units 41, 42, there is a pair of accumulation (supply) cases 11.42 in which sheets 2 are carried out via guide plates 7A, 7B. A plate 17 and a guide plate 1G are arranged to sort the sheets 2 to be taken out from the erasing units 41 and 42.
We will take pictures separately for cases 11 and 15.

In the illustrated state, the plate 17 guides the sheet 2 to the lower stacking case 15, the lower stacking case 15 is stacking the sheets, and the other (upper) stacking case 11 is photographing the sheet 2. It is in a state where it is being supplied to the section 10.

These pair of accumulation cases 11 and 15 are adapted to repeat accumulation and supply alternately. That is, all the sheets 2 accumulated in the lower accumulation case 11 are
, the collection case 11 moves to the collection position indicated by the upper dashed line 11'. After that, the stacking case 15 in which the sheets 2 that were at the stacking position were stacked is moved to the upper chain line 15'.
The sheet 2 is moved to the supply position (not shown), and the sheet 2 is sent out to the photographing section 10 again from there.

In this way, the stacking cases 11 and 15 are configured to be movable between the stacking position and the supplying position of the sheets 2, respectively. When sheets 2 are being supplied from one stacking case, the other stacking case is configured to be able to stack sheets 2, and when one stacking case becomes empty, it is switched to the other stacking case where sheets 2 are stacked. An accumulation of “
- Sheet 2 can be supplied from the source.

Shutters 8A and 8B are arranged between the entrance of the erasing unit 41, 42 and the belt pair 34 to prevent light from the erasing unit 41, 42 from leaking outside.

In the above-mentioned actual mm, the path of the sheet 2 starts from the imaging section 10, passes through the reading section, the belt groups 33A to 33E1 and the erasing section 40 in this order, and returns to the accumulation cases ii and is. It is once accumulated in Is. This iWI is temporary, and an appropriate number of seeds 2
When the sheets 2 are accumulated, the sheets 2 are transferred to the supply position and sent to the photographing section again for reuse.

In addition, the above fruit/I! In this embodiment, the collecting case 11.15 is provided between the photographing unit 10 and the erasing unit 40, but the position is not limited to this. For example, reading section 2017
It may be provided before or after 1.

In the radiographic image information recording/reading device installed in the mobile medical examination type of the present invention, the sheet 2, which has once been used for imaging, is automatically conveyed to the imaging unit 10 again, circulated, and reused. Therefore, the sheet 2 can be used repeatedly, the device is designed to be compact as a whole, and the speed of photographing can be increased. Furthermore, since the entire device is integrated into one device, it is easy to install it in a medical examination type.

The device shown in FIG. 1 has the basic configuration shown in FIG. 1, and can be modified into various forms. For example, the above-mentioned pre-reading and main reading are performed in the reading section 20. First, the sheet 2 is sent by the belt 22.24 for sub-scanning.
4 in the opposite direction to return the sheet 2, and then feed the sheet in the same direction again for main reading. Alternatively, when the belts 22, 24 are rotated in the opposite direction to return the sheet 2, it is also possible to carry out the main reading and then feed the sheet 2 in the direction of the light for the next process.

Hereinafter, various other embodiments of the radiographic image information recording/reading device installed in the mobile medical examination type of the present invention will be explained with reference to the drawings.

Figure 2, like Figure 1, shows the shape f, which is suitable for photographing the chest of a human body.
An example of an f1 (chest type) device is shown.

Similar to the embodiment of FIG. 1, this Vf 1120 is mounted on a motor vehicle 130. As shown in the figure, this device 120 has an overall shape of a single character, in which a single character-shaped circulation passage 101 is formed, and four stimulable phosphor sheets 102
are circulated and conveyed on this circulation path 101 at appropriate intervals by conveyance means such as conveyance rollers and conveyance belts.

Image recording section <m-shaped section) 105 is located on the circulation passage 101.
, an image reading section 106 , and an erasing section 107 are sequentially arranged in the sheet traveling direction (in the direction of the arrow).

In the imaging unit 105, radiation emitted from a radiation source 110 passes through the subject 101 and enters the sheet 102, so that radiation image information of the subject is accumulated and recorded on the sheet 102. In this embodiment, the imaging unit 10
The position of 5 can be adjusted up and down.

The positive-shaped sheet is conveyed along the circulation path in the direction of the arrow by a circulation conveyance means 103 such as a drive roller or a conveyance belt, and enters the image reading section 106 .

The image reading unit 106 includes an excitation light source 162 that emits excitation light 161 such as a laser beam that scans the sheet 102, and a photomultiplier that reads stimulated luminescence light emitted from the sheet 102 by scanning the excitation light and obtains an electrical image signal. etc. light? 12 reading means 163. 164 is a galvanometer mirror. Since this image reading unit 106 reads the sheet 102 while advancing it at a constant speed, there is a space 165 for one sheet where the sheet 102 immediately before reading starts and a space 165 for one sheet where the sheet 102 immediately after reading is completed. It has a space 166.

The image signal read by the photoelectric reading means 163 is sent to an image processing circuit (not shown), subjected to necessary image processing, and then sent to a necessary image reproduction device.

As mentioned above, this playback device may be a display such as a CRT, or a recording f! that performs optical scanning recording on a photosensitive film. It may be placed. Alternatively, instead of the reproducing device, an image signal recording device such as a magnetic tape may be connected to the photoelectric reading means 163 as in embodiment #1 in FIG.

Gao, Yu (D@@ 1201C Oiko Ayo.r5V'1
6J' and "book reading" can be performed. That is, once the sheet 102 is sent by the endless belts 165 and 166 for sub-scanning and first read ahead, the endless belts 165 and 16G are reversed to return the sheet 102 to the reading position, and then the endless belts 165 and 166 are The main reading can be performed by rotating it in the normal direction.

The read sheet 102 is sent to the erasing section 101 by the circulating conveyance means 103.

The erasing section 107 includes a fluorescent lamp and a tungsten lamp.

A large number of erasing light sources 171 such as sodium lamps, xenon lamps, iodine lamps, etc. are arranged, and the sheet 102 is irradiated with visible light by the erasing light sources 171 to emit residual radiation energy on the sheet.

The erasing section sheet is transferred to the photographing section 1 again by the circulating conveyance means 103.
Sent to 05.

The erasing section 107 stores one sheet and performs the erasing process. After the sheet 102 is carried into this erasing section, it stops in the erasing section 101 and is exposed to light for the same time as the reading time. Then, the next sheet is carried into the erasing section and the same erasing process is repeated. In other words, the erasing processing conditions in this erasing section are such that the time interval at which the sheet is carried in from the erasing section matches the reading time, in other words, the light remains on the sheet by being irradiated with light for the same time as the reading time. Erasing processing conditions such as the amount of irradiated light per unit time are set so that a sufficient amount of light can be irradiated to emit the radiation energy.

Both of the above two embodiments have a chest-type photographing section (image recording section), but the next embodiment has a bed-type photographing section. , the aspect will be explained.

FIG. 3 shows an actual vehicle 200 equipped with a bed-type device 201 that captures and records radiographic images of the chest, abdomen, etc. while the subject is lying on his back. , which shows the aspect. Inside the device 201 are endless belts 202, 20.
3. 204. 205. 206. 207. 20
8. 209, 210. 211. 212. 21
3 and endless belt 203. 204.
207. 210. 211. 21
2. Guide roller 214 that rotates following rotation of 213.
215. 216. 217°? 18. 219. 2
20, and a guide plate 221. 222. 223°224
．． 225. 226, and a nip roller 227. 22
A sheet circulation conveyance system consisting of 8 and forming a circulation path is provided. In this sheet circulation conveyance system, for example, six stimulable phosphor sheets 230 are circulated and conveyed at appropriate intervals in the direction of the arrow in the figure.

Endless belt 2 arranged at the top of the circulation conveyance system
A photographing stand 241 is provided above 02, and the photographing position M on the endless belt 202 (in FIG. 3, the endless belt 102
A radiation source 242, such as an Xla source, is provided at a position opposite to the right side of
and radiation 1;t 242 constitute an image recording section 240.

During radiography of the subject 243, the sheet 230 used for radiography is placed at the radiography position on the endless belt 202 as shown in the figure, and the radiation source is placed while the subject 243 lies supine on the radiography table 241. 242 is driven to turn on. As a result, the transmitted radiation image of the patient 243 is projected onto the sheet 230, and the radiation image information of the patient 243 is projected onto the sheet 230.
It is accumulated and recorded in 30.

At the right end position in the figure of the sheet circulation conveyance system, there is an image reading unit 25.
0 is set. In this image*reading section 250,
A laser light source 251 is installed above the endless belt 208 that constitutes the reading section 250, and the output laser light 252 is transmitted to the sheet 230 on the endless belt 208.
mirror 253 for scanning in the width direction. Galvanometer mirror 254. A mirror 255 and a mirror 256 are provided, and by the reciprocating movement of the galvanometer mirror 254, the laser beam 252 is main-scanned over the sheet 230 on which the radiation image has been accumulated and recorded. Note that after the radiation image is recorded on the sheet 23G in the image recording section 240, the sheet 23G is transferred to the image reading section 2 by driving the sheet circulating conveyance system.
50. Also, the sheet of laser light 252
A condensing reflective mirror 257 is disposed along the main scanning line at a scanning position on 230, and stimulated luminescent light emitted from the sheet 230 by irradiation with the laser beam 252 is reflected directly or by the condensing reflective mirror 251. Condensing optical element 25
The light enters the condensing optical element 258 from the incident end surface 258A of the element 2, and is guided through the condensing optical element 258 by total reflection.
Photomultiple 259 connected to the injection end surface 258B of 58
The stimulated luminescence light is then read out photoelectrically. At the same time as the main reverse scanning of the laser beam 252 is performed as described above, the sheet 230 is conveyed by the endless belt 208 in the direction of the arrow in the figure (that is, the direction substantially perpendicular to the main scanning direction) and the sub-scanning is performed. The stored radiation image information is read over the entire surface of the sheet 230. The two-way signal read by the photomultiplier 259 is sent to an image processing circuit (not shown), subjected to necessary image processing, and then sent to a necessary image reproduction device. As mentioned above, this reproducing device may be a display such as a CRT, or a recording device that performs optical scanning recording on a photosensitive film. Alternatively, instead of the reproducing device, an image signal recording device such as a magnetic tape may be provided as in the actual IM mode shown in FIG.

Note that the time required to read the radiation image information from one sheet 230 is generally longer than the time required to record (photograph) the radiation image information on the sheet 230, but the recorded sheet 230 can be used, for example, on an endless belt. 207
．． 206. 205. 204. By leaving one sheet on each sheet 202, the six sheets 230 can be used one after another and recording can be completed within a short period of time. Furthermore, as mentioned above, prior to the above-mentioned reading operation (main reading) to obtain a visible image for observation and interpretation, excitation light with lower energy than the excitation light to be irradiated in the main reading is used. A reading operation (pre-reading) is performed to grasp the accumulated record information of the radiographic image information accumulated and recorded on the stimulable phosphor sheet, and the accumulated record information of the radiographic image information is grasped, and then the main reading is performed. By appropriately adjusting the reading gain or performing appropriate signal processing based on the IyJ pre-read information, it is possible to eliminate the influence of variations in profile conditions, or to obtain radiographic images with excellent aptitude for interpretation. However, in this apparatus as well, after reading the image, the sheet 230 sent onto the endless belt 209 is transferred to the endless belt 209J5 and the endless belt 207. By reversing 208 and returning it to the image reading position, the above-mentioned "pre-reading" and "main reading" can be performed.
can be done.

The sheet 230 whose image has been read is sent to the erasing section 270 by the endless belt 209. This erase section 2
70 consists of a box 211 and a large number of erasing light sources 272 such as fluorescent lamps, tungsten lamps, sodium lamps, xenon lamps, iodine lamps, etc. arranged inside this box 271; is conveyed by the endless belt 209 until its tip touches the nip roller 221. The sheet 230 is then sent into the box 271 by the rotating nip roller 227. When the sheet 230 is sent into the box 271, the shutter 213 is closed. The erasing light source 272 inside the box 271 mainly emits light in the excitation wavelength range of the stimulable phosphor of the sheet 230, and the radiation energy remaining in the sheet 230 after reading the image is transferred to the sheet 230. When such light is irradiated, it is emitted from the sheet 230. Note that since the shutter 273 is closed at this time, the erasing light does not leak and enter the image reading section 250 and generate noise in the read signal.

The sheet 230, on which the afterimage has been erased to such an extent that radiation image information can be recorded again, is discharged from the erasing section 270 by rotating the nip roller 228.

The discharged sheet 230 is placed on an endless belt 210°211, 212. 213, the image recording unit 24
However, if another sheet 230 is stuck first, the sheets are sequentially placed on the endless belts 213, 212, 211, and 210 and wait.

Further, when the image recording and reading operations are completed, the last sheet 230 undergoes afterimage erasure in the erasing section 270, and then is sent endlessly onto the sheet 209 by rotating the nip roller 227 in the opposite direction. and waits on the belt 209.

As explained above, the endless belts 202 to 213 that constitute the sheet circulation conveyance system and the nip
) roller 227. 228 is controlled in conjunction with the operations of the image recording section 24G, the image reading section 250, and the erasing section 270 (this can be done by employing a known sequence control), and conveys or places the sheet 230.

Next, FIGS. 4 to 6 show further different modifications of the radiographic image recording and reading apparatus mounted on an automobile. (A car is not shown in the following examples.) FIG. 4 shows a chest type similar to the examples of FIGS. 1 and 2. In this example, a stimulable phosphor sheet (not shown) on which a radiographic image of the subject has been stored and recorded in the imaging section 410 is conveyed upward by a conveyor belt 411 toward a reading section 420 . The reading section 420 is scanned with excitation light by a device d similar to the embodiment shown in FIG. 1, and stimulated luminescence light is read photoelectrically. In this reading unit 420, the sheet is reciprocated in the same manner as described above, and pre-reading is performed in the first forward movement, and the second
The main reading may be performed during the first forward movement, or the pre-reading may be performed during the first forward movement and the main reading may be performed during the next backward movement.

The sheet that has passed through the reading section 420 passes through a belt group 430 and then enters an erasing section 440, after which it is conveyed again to the photographing section 410 and is reused.

FIG. 5 shows an example of a bed type in which a play is performed while the subject is lying down, and the functions of each part are the same as in the two embodiments described above. The imaging unit 510 is positioned horizontally, and a bed (not shown) on which the subject lies is placed above it.

The photographed sheet is sent out to the right in the figure, and is sent to the reading section 520.
Pre-reading and main reading are performed by reciprocating motion. After reading, the sheet is sent to the erasing section 540 via the belt group 530, and then sent again to the photographing section 510, and the sheet is circulated.

The belt group 530 has four parts where seats are waiting.
), (B), (C), and (D), and the sheet that has passed through the reading section 520 enters the waiting zones (A) to (D>) into the manual erasing section 540.These four waiting zones <A )～(D
), four sheets that have been read after being photographed can be placed on standby, and are stored in the erasing section 540, the m-shaped section 510 . Reading section 5
Including around 20 sheets, a maximum of about 8 sheets can be reused. Note that in the above embodiment, the belt group 53
0 is provided between the reading section 52G and the erasing section 540.

It may be provided upstream or downstream of the imaging unit 510.

Figure 6 also shows an example of a bed-type device.
After the sheet is sent from the photographing section 610 to the reading section 620, the sheet is reciprocated in the reading section 620 by a reciprocating roller 620A to perform pre-reading (S) and main reading ()l).
Then, the sheet is sent through the shutter 630 to the erasing section 640, and then to the photographing section 610, where it is circulated.

In this embodiment, the sheet is (S
Pre-reading is performed while moving in the ) direction, main reading is performed while moving in the opposite direction (H), and the data is directly sent to the next erasing section 640.

As is clear from the description of the above-mentioned embodiments, the radiation image information recording/reading device installed in the mobile medical examination type of the present invention has a stimulable phosphor sheet that circulates through the photographing, reading, and erasing sections. Because of this, the sheet can be used repeatedly and the overall structure is compact, which is extremely advantageous in practice. It is especially suitable for cases where a large number of images must be taken in succession, such as in mass medical examinations.
It is particularly useful for putting this type of radiation imaging system into practical use and spreading it.

In each of the embodiments described above, it is preferable that reading is not performed at the timing when the sheet is fed into the erasing unit, so that strong light from a lamp such as a fluorescent lamp of the erasing unit does not enter the sensitive reading unit and cause noise. Also, at this time, it is desirable to turn off the power to the photomulti to prevent strong light from entering the photomulti.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are schematic diagrams showing various embodiments of mobile medical examination type IIA according to the present invention, and FIGS. 4 to 6!
FIG. 3 is a schematic diagram showing an example of a radiation image information recording/reading device installed in each of the other embodiments. □ 1...Test object 2...Storage phosphor sheet 3.8A, 88. 330...Shutter 4.5, 6.7A, 7B, 16, 18.19...
・Information board 10, 110. 210. 310... Jumping part (image recording part) 11, 15... Accumulation (supply) case 11... Distribution is on board 20, 120. 220. 320... Reading unit (image reading unit) 22, 24... Feeding belt 25...
Laser light source 28... Focusing optical element 29...
・Photomaru 34...Distribution is for belt pair 40, 140. 240. 340--Erase part 50--Mobile examination type 60--Automatic
Car 70... Radiation image information recording/reading device 80.
. . . Image signal recording device 101 . jI reading section 107... Erasing section 162... Excitation light @ 163... Photoelectric reading means 201... Radiation image information reading device 202-213... Endless belt 214-220
...Guide rollers 221 to 22G...Guide plates 227, 228...Nip rollers 230, 290...Stormative phosphor sheet 240.
...Image recording section 241...Photographing stand 242...
・Radiation source 243... Subject (subject) 250
...Image reading unit 252...Laser light 251...
- Laser light sources 253, 255. 256. 257...
...Mirror -254...Galvanometer mirror 258...Condensing optical element 259...Photomulti 2
7G... Erasing section 272... Erasing light source Figure 4 Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1) Circulating transport means for transporting at least one stimulable phosphor sheet capable of storing and recording radiographic images along a predetermined circulation path; an image recording section that accumulates and records a radiographic image of the subject on the sheet by irradiating radiation through the subject; an excitation that is located in the circulation path and scans the sheet on which the radiographic image has been accumulated and recorded in the image recording section; an image reading unit having an excitation light source that emits light; a photoelectric reading unit that reads stimulated luminescence light emitted from a sheet scanned by the excitation light to obtain an image signal; A radiation image information recording/reading device characterized by comprising an erasing section that releases residual radiation energy on a sheet after an image is read in a reading section and before an image is recorded on the sheet. A mobile medical examination vehicle mounted on a car. 2) The circulation conveyance means sequentially conveys a plurality of stimulable phosphor sheets to an image recording section, an image reading section, and an erasing section, and simultaneously delivers one sheet each to the image recording section and the image reading section. 2. The mobile medical examination vehicle according to claim 1, wherein the erasing section is configured to stop at least one sheet. 3) The mobile medical examination vehicle according to claim 1 or 2, wherein the circulating conveyance means is composed of a plurality of endless belts arranged in series. 4) Among the circulating conveyance means, at least one of the conveyance means provided between the image recording section and the image reading section, between the image reading section and the erasing section, or between the erasing section and the image recording section. The movement according to claim 1, 2 or 3, wherein the stimulable phosphor sheet has a sufficient length to keep at least one of the stimulable phosphor sheets on standby. Medical examination car. 5) Any one of claims 1 to 4, wherein the circulation conveyance means includes a portion for temporarily accumulating the sheets upstream or downstream of the image recording section. The mobile medical examination vehicle described in paragraph 1. 6) The mobile medical examination vehicle according to any one of claims 1 to 5, wherein the image reading section performs both pre-reading and actual reading of images. 7) The mobile medical examination vehicle according to claim 6, wherein the image reading unit performs pre-reading and main reading using separate excitation light sources and photoelectric reading means. 8) The mobile medical examination vehicle according to claim 6, wherein the image reading section performs pre-reading and main reading using the same excitation light source and photoelectric reading means. 9) The image reading section performs pre-reading while feeding the sheet in one direction using the same excitation light source and photoelectric reading section, then returns the sheet once in the opposite direction, and then feeds it in the same direction as the one direction. 9. The mobile medical examination vehicle according to claim 8, wherein the mobile medical examination vehicle is used for reading books while reading a book. 10) The image reading section is characterized in that the image reading section performs pre-reading while feeding the sheet in one direction using the same excitation light source and photoelectric reading means, and then performs the main reading while returning the sheet in the opposite direction. A mobile medical examination vehicle according to claim 8. 11) Circulating conveyance means for conveying at least one stimulable phosphor sheet capable of accumulating and recording a radiation image along a predetermined circulation path, which is located in the circulation path and irradiates the sheet with radiation through a subject. an image recording section that accumulates and records a radiographic image of the subject on the sheet; an excitation light source located in the circulation path that emits excitation light that scans the sheet on which the radiographic image is accumulated and recorded in the image recording section; , an image reading section having a photoelectric reading means for reading the stimulated luminescence light emitted from the sheet scanned by the excitation light to obtain an image signal; A radiation image information recording/reading device comprising: an erasing section that releases residual radiation energy on the sheet prior to image recording on the sheet after image recording; A mobile medical examination vehicle equipped with an image signal recording device that performs a medical examination. 12) Circulating conveyance means for conveying at least one stimulable phosphor sheet capable of accumulating and recording a radiation image along a predetermined circulation path, and irradiating the sheet with radiation through a subject in the circulation path; an image recording section that accumulates and records a radiographic image of the subject on the sheet; an excitation light source located in the circulation path that emits excitation light that scans the sheet on which the radiographic image is accumulated and recorded in the image recording section; , an image reading section having a photoelectric reading means for reading the stimulated luminescence light emitted from the sheet scanned by the excitation light to obtain an image signal; A radiation image information recording/reading device comprising: an erasing unit that releases residual radiation energy on the sheet prior to image recording on the sheet after image recording; A mobile medical examination vehicle equipped with a reproduction device for reproducing transparent images.