JPS59211264A - Radiation image detecting method - Google Patents

Abstract

PURPOSE:To eliminate a problem of adverse influence affected to the quality of a picture occurred in a mechanical carriage of a panel or a detector by photoelectrically reading out an intensity light via a photodetector, thereby shortening the detecting time in a radiation image converting method utilizing the intensity fluorescent unit, and simplifying the detection. CONSTITUTION:Radiation passed through an object is incident to a radiation image conversion panel. Then, the panel and a photodetector are superposed closely by disposing a protective film 1 of the panel and the insulating layer 4 of the photodetector inside. A photosensitive element is, for example, formed of a photodiode 5 of a photoreceptor provided on the layer 4, and an MOSFET6 of a transfer unit. When an electromagnetic wave of an exciting wavelength range of an intensity fluorescent unit is emitted from a support 3 side of the panel 3, the accumulated image of the radiation energy formed on a fluorescent layer 2 is radiated as fluorescent (intensity light emission). Only the emitted fluorescent light is passed through the layer 4 of the filter to be photosensed by the photodiode 5, thereby generating a signal charge in the photodiode 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radiation image detection method. More specifically, the present invention relates to a radiation image detection method that utilizes the combination of a radiation image conversion panel and a photosensitive element.

Traditionally, the so-called radiographic method, which combines a radiographic film with an emulsion layer made of a silver salt photosensitive material and an intensifying screen, has been used to detect a radiation image of a subject and obtain it as an image. has been done. As an alternative to the conventional radiographic method described above, for example, a stimulable phosphor as described in U.S. Pat. Radiographic image conversion methods utilized are known.

In this method, radiation transmitted through the subject or radiation emitted from the subject is absorbed into a stimulable phosphor, and then this phosphor is exposed to electromagnetic waves (excitation light) such as visible light and infrared rays in a time-series manner. By exciting the phosphor, the radiation energy accumulated in the phosphor is converted into fluorescence (1i[l!
The method consists of emitting the fluorescent light as (exhaustive luminescence) and detecting this fluorescence.

So far, in the radiation image conversion method, radiation image detection has been carried out using a radiation image conversion panel (stimulable phosphor sheet) containing a stimulable phosphor. It has been proposed to photoelectrically read out the energy image of the image using a radiation image reading device.

The radiation image conversion panel used in the radiation image conversion method described above has a basic structure consisting of a support and a phosphor layer provided on one side of the support. Note that the surface of this phosphor layer opposite to the support (the surface not facing the support) is generally transparent and protected from deterioration or physical impact.

In addition, in radiation image reading devices, usually
As disclosed in Publication No. 11395, etc., a photomultiplier tube is used as a photodetector, and the tip of the photomultiplier tube collects fluorescence emitted from the surface of the radiation image conversion panel. A light guide sheet is provided to guide light to a photodetector.

In other words, the radiation transmitted through the subject or the radiation emitted from the subject is absorbed by the phosphor layer of the radiation image conversion panel, and a radiation image of the subject or subject is formed on the panel as an image of accumulated radiation energy. Ru. Next, the accumulated image formed on this panel is excited by electromagnetic waves (excitation light) such as visible light and infrared rays in a radiation image reading device, and is emitted as stimulated luminescence (fluorescence). The emitted fluorescence is guided through a light-guiding sheet, then photoelectrically read by a photomultiplier tube and converted into an electrical signal.The obtained electrical signal is used to create a radiation image of the subject or subject. can do.

The radiation image conversion method has the advantage that it is possible to obtain a radiation image rich in information with a much lower exposure dose than when conventional radiography is used. Therefore, this radiation image conversion method has a very high utility value especially in direct medical radiography such as X-ray photography for the purpose of medical diagnosis.

However, the reading of the radiation image conversion panel is 1,
Conventionally, the panel was irradiated with light with a small beam diameter such as a laser beam in time series, that is, the laser beam was scanned (main scanning or sub-scanning), and the fluorescence emitted from the panel at this time was collected using a photomultiplier tube. This is done by detecting the information using a photodetector such as a photodetector and converting it into an electrical signal, and this reading operation requires a considerable amount of time (several tens of seconds).

In addition, when reading out a radiation image conversion panel, in order to detect the fluorescence emitted in time series from each phosphor particle group on the radiation image conversion panel irradiated with excitation light, it is usually The panel is being moved (sub-scan or main scan).

Therefore, the operation for detecting (reading) the radiation image stored in the radiation image conversion panel is complicated.

Furthermore, if a light-guiding sheet or the like is used in combination with a photomultiplier tube to efficiently detect fluorescence emitted from a radiation image conversion panel, the readout device becomes complicated and operational problems arise. is likely to occur.

Therefore, the main object of the present invention is to provide a radiation image detection method in which the above-mentioned problems in radiation image conversion methods using stimulable phosphors are solved or the drawbacks are reduced. It is something to do.

The above purpose is to absorb the radiation transmitted through the subject or emitted from the subject into a radiation image conversion panel having a phosphor layer containing a stimulable phosphor, and then to absorb the radiation transmitted through the subject or emitted from the subject. After superimposing a photodetector in which photosensitive elements are regularly arranged in two dimensions, the panel is irradiated with electromagnetic waves to release the radiation energy stored in the panel as photostimulated light, This can be achieved by the radiation image detection method of the present invention, which comprises photoelectrically reading this stimulated light using the photodetector.

That is, according to the study of the present inventor, after radiation such as X-rays transmitted through the subject or emitted from the subject is absorbed by the stimulable phosphor of the radiation image conversion panel, the radiation image conversion panel is superimposed on a photodetector consisting of a large number of photosensitive elements, and then the panel is irradiated with light in the excitation wavelength region of the photostimulable phosphor, so that the fluorescence emitted from the panel (IL141 emission) is detected by the photosensitive elements. It has been found that it is possible to receive light and convert it into an electrical signal, and to obtain image information regarding a radiation image of a subject or a subject directly as an electrical signal.

Therefore, according to the radiation image detection method of the present invention, compared to the radiation image readout methods proposed so far, since a photosensitive element is used as a photodetector, radiation image information is The electric signal can be obtained as an electric signal for each pixel of a large number of photosensitive elements, and the detection time of a radiation image can be significantly shortened.

In addition, the photodetector is made up of a large number of photosensitive elements and has the same size as the radiation image conversion panel, and during readout, the photodetector and the radiation image conversion panel are overlapped so as to be in close contact with each other. By operation, the fluorescence emitted from the panel surface under the irradiation of excitation light is detected in each pixel of a large number of photosensitive elements adjacent to this panel, so that the panel as in the readout operation of a conventional radiation image conversion panel This simplifies the radiographic image detection operation.

Furthermore, unlike conventional methods, there is no need to install a light-guiding sheet to collect the fluorescent light emitted from the panel surface, so the readout device can be downsized, making it possible to capture the radiation image as described above. In the reading operation of the conversion panel, it is possible to eliminate problems such as adverse effects on image quality caused by mechanical transportation of the panel or detector.

This also means that even when the intensity of the radiation transmitted through or emitted from the subject is weak, the radiation image can be detected with high sensitivity. It can also be used effectively in certain situations.

The present invention will be explained in detail below.

The photodetector used in the present invention has a large number of photosensitive elements regularly arranged two-dimensionally in the horizontal direction to form a plane. A photosensitive element used in a photodetector includes, for example, a light receiving part for receiving fluorescence emitted from a phosphor layer, and a time series output of electric charges obtained through photoelectric conversion in the light receiving part as an electric signal. A known solid-state image sensor using an amorphous semiconductor or the like can be used as the photosensitive element.

An example of such a solid-state image sensor is MOS (Met
al Oxide Sem1conductor)
, CCD (Chatted Coupled De
vice), BBD (Bucket Bri
gadeDevice ), CI D (Char
For example, sensors such as ge l5olated device) can be mentioned. Among these, particularly preferred is MO
It is S. In addition, photoconductive materials used in this solid-state image sensor include amol 77 silicon Ca-3i), Z
Examples include nO and CdS.

An insulating layer is provided on the side of the photodetector that is in contact with the radiation image conversion panel. Examples of the material for the insulating layer include light-transmitting and insulating materials such as glass and transparent polymer materials. This insulating layer has the function of a filter that transmits only light in the wavelength range of the stimulable phosphor included in the radiation image conversion panel and cuts light in the wavelength range of the excitation light. This is desirable. The function of such an insulating layer as an optical filter is, for example,
It can be provided by coloring the insulating layer with a colorant having selective light transmittance as described above.

Alternatively, a single layer of a filter having light transmittance as described above may be provided on the insulating layer.

Furthermore, the radiation image conversion panel used in the present invention basically consists of a support and a phosphor layer, but if the phosphor layer is self-supporting, it may be composed only of the phosphor layer. You can leave it there.

The support used is one that transmits at least excitation light, and can be suitably selected from various materials used as supports for intensifying screens in conventional radiography. Examples of such materials include films of plastic materials such as cellulose acetate, polyester, polyethylene terephthalate, and the like.

The phosphor layer is basically a layer consisting of a binder containing and supporting particles of stimulable phosphor in a dispersed state.

The stimulable phosphor used in the present invention is a phosphor that exhibits stimulated luminescence when irradiated with radiation and then with excitation light as described above, but from a practical point of view, the wavelength is 40.
300 to 5 by excitation light in the range of 0 to 800 nm.
It is desirable that the phosphor be a phosphor that exhibits stimulated luminescence in a wavelength range of 0.00 nm.

Examples of such stimulable phosphors include U.S. Pat.
Described in the specification of No. 859,527 Sm, Th02: E
r, and a phosphor represented by a composition formula such as La2O2S:Eu, Sm, etc., ZnS:Cu, Pb, which is described in JP-A-55-12142.
B 8LO11x A l 203 :Eu [However,
0.8≦X≦10], and M”0L1xS i02
: A [However, M is Mg, Ca, Sr, Zn,
Cd or Ba, A is Ce, Tb, Eu, Tm
, Pb, Tn, Bi, or Mn, and X is 0.5
≦X≦2.5] A phosphor represented by a composition formula such as
(B a H-) c -y, M g
X, Cay) FX:
aEu2+ [where X is at least one of CKL and Brcy), and X and y are O< X +
y≦0.6 and xysO, and a is 10-8≦a
A phosphor represented by the composition formula: ≦5×lO″4, LnO described in JP-A-55-12144
X: xA [where Ln is La, Y, Gd, and Lu
at least one of the following, X is at least one of C and Br, A is at least one of Ce and Tb, and X is O<x<0.1. The phosphor represented by
l-z, M”x) FX: yA [However, MIE is M
At least one of g, Ca, S r, Zn, and Cd, X is 0, Br, and at least one of I, A is Eu, Tb, Ce, "jm, Dy, Pr, H
at least one of o, Nd, Yb, and Er, and X is 0≦X≦0.6, and y is 0≦y≦0.2
A phosphor represented by the composition formula of
FX* xA: yLn [However, Mlf is Ba,
At least one of Ca, Sr, Mg, Zn, and Cd, A is Bed, MgO, CaO, SrO, B
ad, ZnOlAM, 03, Y2O3, La2O3, I
n203, S io2, TlO2, Z r02 ,
GeO2, SnOz, Nb2O5, Ta20
5, and at least one of The2, Ln is E
u, Tb, Ce, Tm, Dy, Pr, Ho, Nd
, Yb, Er, Sm, and Gd, X is at least one of cfL, Br, and I, and X and y are each 5×lO→≦X
≦0.5, and Okuy≦0.2.
e, s-x + MMx) F 2 conflict aB aX2
:yEu, zA [where MM 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, a,
X, y, and 2 are each 0.5≦a≦1.25.0
≦X≦1.10-s≦y≦2 X 10-', Oyobi O
A phosphor represented by the composition formula <z≦10-] is described in JP-A-57-23673 (B
as-x + M”x) F
2 @ aB aX 2 :yEu
, zB[However, MI[ is beryllium, magnesium,
at least one of calcium, strontium, zinc, and cadmium, X is at least one of chlorine, bromine, and iodine, and a, x, y, and 2 are each 0.5≦a≦1.25 , O≦X≦1.10
−6≦y≦2×10−1, and O<z≦2×10−′
A phosphor represented by the composition formula of
Bal-X, M”X) F2 * aBaX
2: yEu, zA [However, MM is beryllium, magnesium, calcium, strontium, zinc,
and at least one of cadmium, X is chlorine,
At least one of bromine and iodine, A is at least one of arsenic and silicon, a, x, y,
and 2 are respectively 0.5≦a≦1.25.0≦X≦1
．． 10-”≦y≦2×io-′, and 0<z≦5X1
A phosphor represented by the composition formula M"OX:xCe [where MII[
are Pr, Nd, Pm, Sm, Eu, Tb,
is at least one trivalent metal selected from the group consisting of Dy, Ho, Er, Tm, Yb, and Bi, and X is C
1 and/or Br, and X is O<x<O, 1]. Listed B EL l-x M x yx L x
/2 F X :yEu&[However, M is Li, Na
, represents at least one alkali metal selected from the group consisting of Rb and Cs; L is Sc, Y, L
a, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy
, Ho, Er, Tm, Yb, Lu, A sentence, Ga, In,
and TU; X represents at least one halogen selected from the group consisting of CI, Br, and ■; and X represents 10-2≦X≦0 .5, y is o<y≦o, i
A phosphor represented by the composition formula of "BaFX. is at least one kind of /\rogen selected from the group; A is a fired product of a tetrafluoroboric acid compound; X is 10-s≦
x<O, j, 1! is a phosphor represented by the composition formula: yEu", where X
is at least one halogen selected from the group consisting of C9, Br, and ■; A is a monovalent or divalent metal salt of hexafluorosilicic acid, hexafluorotitanic acid, and hexafluorozirconic acid; It is a fired product of at least one compound selected from the group of hexafluoro compounds; and X is 104≦X≦O0t
, y is o<y≦0.1], BaFX@xNaX':aEu2') [However, , X and X'' are each at least one of CfL, Br, and I, and X and a are respectively O<x≦2 and 0<a≦0.2]. Phosphor, described in Japanese Patent Application No. 57-166696 by the present applicant
' :yEu2+:zA [However, yllll is Ba,
is at least one kind of alkaline earth metal selected from the group consisting of Sr and Ca; X and X' are each at least one kind of halogen selected from the group consisting of Cl, Br, and ■; A is V , Cr, Mn, F
at least one transition metal selected from e, Co, and Ni; and X is 0<x≦2, and y is o<y≦
0.2, and Z is 0<z≦10-];'ebM'"X"
260M"X"' 3++ x A: y E u'
2+[However, MI[ is at least one kind of alkaline earth metal selected from the group consisting of Ba, Sr, and Ca; Ml is at least one kind selected from the group consisting of Li, Na, Rb, and C8. is an alkali metal; Ml1 is at least one divalent metal selected from the group consisting of Be and Mg; M■ is AM, Ga, In
, and Tl; A is a metal oxide; X is CI,
Br, and ■ are at least one kind of halogen selected from the group consisting of; xo, Xp, and X″° are F,
is at least one halogen selected from the group consisting of C1, Br, and ■; and a is O≦a≦2, b
is O≦b≦1O-2, C is 0≦C≦1O-2, and a+
b+c≧io−”; X is 0<x≦0.5, y is o
Examples include a phosphor represented by the composition formula <y≦0.2].

Note that the stimulable phosphor used in the present invention is not limited to the above-mentioned phosphors, but any phosphor that exhibits stimulated luminescence when irradiated with radiation and then irradiated with excitation light. There may be.

Examples of binders for the phosphor layer include proteins such as gelatin, polysaccharides such as dextran, or natural polymeric substances such as gum arabic; and polyvinyl butyral, polyvinyl acetate, nitrocellulose, ethylcellulose, and vinylidene chloride/chloride. Vinyl copolymer, polymethyl methacrylate, vinyl chloride/vinyl acetate copolymer, polyurethane, cellulose acetate butyrate,
Examples of binders include synthetic polymeric substances such as polyvinyl alcohol and linear polyester.

The phosphor τ' layer can be formed on the support, for example, by the following method.

First, the above-mentioned stimulable phosphor particles and binder are added to a suitable solvent (e.g., lower alcohol, ketone, ester, ether) and mixed thoroughly, so that the phosphor particles are dissolved in the binder solution. Prepare a uniformly dispersed coating solution.

The mixing ratio of the binder and stimulable phosphor particles in the coating solution varies depending on the characteristics of the intended radiation image conversion panel, the type of phosphor particles, etc., but in general, the mixing ratio of the binder and stimulable phosphor particles is in the range of 1:1 to 1:100 (weight ratio), and particularly preferably in the range of 1:8 to 1:40 (weight ratio).

The coating liquid contains a dispersant to improve the dispersibility of the phosphor particles in the coating liquid, and a dispersant to improve the bonding force between the binder and the phosphor particles in the phosphor layer after formation. Various additives, such as plasticizers, may be mixed to make the material more durable.

The coating solution containing the stimulable phosphor particles and binder prepared as described above is then uniformly applied to the surface of the support to form a coating film. This coating operation can be carried out using conventional coating means such as a doctor blade, roll coater, knife coater, etc. The formed coating film is then dried by gradually heating it.

The thickness of the phosphor layer varies depending on the characteristics of the intended radiation image conversion panel, the type of phosphor particles, the mixing ratio of the binder and the phosphor particles, and is usually 2071 m to 1 mm. However, the thickness of this layer is preferably 50 to 500 ILm.

Note that the phosphor layer does not necessarily need to be formed by directly applying a coating liquid onto the support as described above; for example, it is possible to form the phosphor layer by separately applying the coating liquid onto a sheet such as a glass plate, metal plate, plastic sheet, etc. After the phosphor layer is formed by drying, the phosphor layer may be pressed onto the support, or the support and the phosphor layer may be bonded together using an adhesive.

Preferably, a transparent protective film is provided on the phosphor layer to protect the phosphor layer from physical impact and chemical alteration. This protective film may be made of, for example, a cellulose derivative such as cellulose acetate or nitrocellulose; or polymethyl methacrylate, polyvinyl butyral, polyvinyl formal, polycarbonate,
Polyvinyl acetate, vinyl chloride-vinyl acetate copolymer,
It is formed from synthetic polymeric substances such as polyethylene terephthalate, polyethylene, vinylidene chloride, and polyamide. The thickness of the protective film is preferably about 3 to 20 pm.

However, in the radiation image conversion panel and photodetector used in the present invention, the wavelength range of stimulated luminescence of the stimulable phosphor contained in the panel is used in the light receiving part of the photosensitive element that is the photodetector. It is necessary to use them in combination so that they overlap with the light absorption wavelength range of the photoconductive material. That is, the stimulable phosphor and photoconductive material used in the present invention must be selected so that at least a part of the emission wavelength range of stimulated light overlaps at least a part of the light absorption wavelength range of the photoconductive material. Must be. For example, when α-3t is used as the photoconductive material, the stimulable phosphor is preferably a phosphor having a stimulated emission wavelength around 600 nm. In addition, as a stimulable phosphor, a divalent europium-activated alkaline earth metal fluoride halide phosphor (the peak wavelength of light emission is about 390 nm) has a stimulable emission wavelength in the near ultraviolet to visible range. When using a phosphor, the photoconductive material is Z
nS and CdS are preferred.

Next, regarding the radiation image detection method of the present invention, a partial sectional view of the radiation image conversion panel shown in FIG.
A detailed explanation will be given with reference to an example of a partial sectional view of the photodetector shown in the figure and a circuit diagram of the photodetector shown in FIG.

FIG. 1 shows protective film 1. 1 is a partial cross-sectional view of a radiation image storage panel composed of a phosphor layer 2 containing a ts-exhaustive phosphor and a support 3. FIG.

First, radiation that has passed through the subject (or, if the subject itself emits radiation, that is, the subject, the radiation emitted from the subject) is made incident on the radiation image conversion panel. Radiation having strengths and weaknesses corresponding to the radiographic image of the subject is absorbed by the phosphor layer 2, and an accumulated image of radiation energy (a kind of latent image) corresponding to the radiographic image of the subject is formed on the phosphor layer 2. It is formed.

Next, the radiation image conversion panel and the photodetector are stacked together so that they are in close contact with each other, with the protection layer 1 of the panel shown in FIG. 1 and the insulating layer 4 of the photodetector shown in FIG. 2 facing inside.

FIG. 2 is a longitudinal sectional view of one pixel of the photodetector. The photosensitive element includes a photodiode 5 which is a light receiving section provided on an insulating layer 4 and a MOS:F which is a transfer section.
E T (Metal Oxide Sem1cond
ucter: Field Effect Trans
istor ) 6. The insulating layer 4 has such a light transmittance that it transmits only light in the wavelength range of stimulated luminescence emitted from the radiation image conversion panel, and cuts light in the wavelength range of excitation light. The photodiode 5 includes, in order, a metal layer 7 such as aluminum which is ground, and a p-type α-3i layer:
H layer 8, i-type α-Si: H layer 9 and tin dioxide (
The transparent electrode layer 10 is made of S n O2). Also MOS
: The FET 5 includes metal layers 11 and 12 such as aluminum provided at both ends, an α-3i:8 layer 13 provided in this order inside these metal layers, an insulator layer 14 of silicon (S10□), and aluminum etc. transfer electrode 15. This metal layer 12 is a drain and is connected to the transfer register.

On the other hand, the transfer electrode 15 is a gate and is connected to a scanning pulse generator.

FIG. 3 is a schematic circuit diagram of a photodetector.

One pixel 16 corresponds to FIG. 2 and is composed of a light receiving section 17 and a transfer section 18. Each transfer section is connected to a scanning pulse generator 19 and a transfer register 20, respectively. The transfer register 20 is provided with an output terminal 21 .

Next, the support 3 of the radiation image conversion panel shown in FIG.
When electromagnetic waves in the excitation wavelength region of the stimulable phosphor are irradiated from the side, the accumulated radiation energy image formed on the phosphor layer 2 is emitted as fluorescence (stimulated luminescence). This fluorescence is proportional to the intensity of radiation energy absorbed by the phosphor layer 2. Only the emitted fluorescence passes through the insulating layer 4 which also serves as a filter of the photosensitive element shown in FIG. 2, and is received by the photodiode 5, where signal charges are generated. In this way, a signal charge is generated in each pixel of the photosensitive element in proportion to the luminance of fluorescence, that is, the intensity of the radiation incident on the phosphor layer of the radiation image conversion panel.

In the circuit diagram shown in FIG. 3, when the scanning pulse generator 19 sends a transfer pulse to each pixel in the two most rows, each transfer unit in the top row has one switch (in FIG. 2, the transfer electrode 15 A voltage is applied to the metal layers 11 and 12, and a current flows between the metal layers 11 and 12).

That is, the signal charges generated in the photodiode 5 in FIG. 2 are transferred through the MOS:FET 6. Therefore, the signal charges of each pixel in the top row are sent to the transfer register 20 simultaneously. From the output terminal 21 of the transfer register 20, electrical signals for each pixel are taken out in a temporal sequence.

In this way, from the top row to the bottom row in Figure 3,
A transfer pulse is sent from the scanning pulse generator 19 to each column,
Electrical signals from each pixel in each column having radiation image information are outputted in time series from the output terminal 21@).

The electrical signal output from the photodetector is amplified by an amplifier,
It is reproduced as an image by an image reproduction device. The electrical signal obtained here may be subjected to image processing such as spatial frequency processing, gradation processing, averaging processing, reduction processing, and enlargement processing, if desired. Then, the obtained image may be recorded on a recording medium or displayed on an image display device. As the recording medium, for example, one that records optically by scanning a photographic light-sensitive material with a laser beam or the like, and one that records on a heat-sensitive recording material using heat rays can be used. In addition, as an image display device, one that displays electronically on a CRT, etc.
Display devices based on various principles can be used, such as one in which a radiation image displayed on a T or the like is recorded on a video printer or the like. Further, this radiation image information of the subject may be recorded and stored on a magnetic tape or the like.

Note that, for example, one pixel of the photosensitive element of the photodetector used in the present invention is about 20011. A size of m×200 pm can be used. When the size of the radiation image conversion panel and the photodetector is, for example, about the same size as a conventional radiation intensifying screen (430 mm x 354 mm), the photodetector is composed of 2150 x 1750 pixels.

α-3t is preferable as a material for a uniform photosensitive element that forms such a large area, and it is desirable that the area of the light receiving portion be as large as possible. In a photodetector having the structure and size as described above, the pulse output from the scanning pulse generator of the photosensitive element is preferably about 3 kHz, for example.

However, the radiation image conversion panel, photodetector, and photosensitive element included therein used in the present invention are not limited to the above-mentioned size.

The radiation image conversion panel used in the present invention has a first
The configuration is not limited to the one illustrated in the figure, but as long as the radiation image of the subject or subject can be accumulated as an energy accumulation image and then emitted as photostimulated light.
Any configuration is possible. Furthermore, the photodetector consisting of a large number of photosensitive elements used in the present invention is not limited to the configuration illustrated in FIGS. It can take any form as long as the photostimulance can be read.

Furthermore, the radiation image detection method of the present invention is not limited to the method exemplified above. For example, the method of detecting a radiation image stored and recorded in the phosphor layer of a radiation image conversion panel may be Before the main operation, a preliminary operation by irradiating weak electromagnetic waves may be performed in order to measure the amount of photostimulated light, and based on the results of this preliminary operation, the amplification factor of the obtained electric signal can be set, and the reproduced image It is also possible to set processing conditions.

[Brief explanation of the drawing]

FIG. 1 is a schematic partial sectional view of a radiation image conversion panel used in the radiation image detection method of the present invention. 1: protective film, 2: phosphor layer, 3: support FIG. 2 is a schematic partial cross-sectional view of a photodetector used in the radiation image detection method of the present invention. 4: Insulating layer, 5: Photodiode, 6: MOS:
FET, 7: metal layer, 8: p-type α-5i: H layer, 9: i
Type α-Si: H layer, lO: transparent electrode layer, 11.12: metal layer, 13: α-3i: H layer, 14: insulator layer, 15
:Transfer electrode FIG. 3 is a schematic circuit diagram of a photodetector used in the radiation image detection method of the present invention. 16: - Pixel, 17: Light receiving section, 18: Transfer section 19: Scanning pulse generator, 20: Transfer register, 21': Output terminal Patent applicant Fuji Photo Film Co., Ltd. Agent Patent attorney Yasuo Yanagawa Figure 1

Claims (1)

[Claims] 1. Radiation transmitted through the subject or emitted from the subject is absorbed by a radiation image conversion panel having a phosphor layer containing a stimulable phosphor, and then the panel and ,
After superimposing a photodetector consisting of a large number of photosensitive elements regularly arranged in two dimensions, the panel is irradiated with electromagnetic waves, and the radiation energy accumulated in the panel is converted into photostimulated light. A radiation image detection method comprising emitting photostimulated light and photoelectrically reading the stimulated light using the photodetector. 2゜L The photosensitive element consists of a light receiving part and a transfer part, and the light receiving part is a photodiode, and the transfer part is a MOS)
2. The radiation image detection method according to claim 1, wherein the radiation image detection method is a radiator. 3. A patent characterized in that the above-mentioned radiation image storage panel has a support and a phosphor layer provided thereon, which is made of a binder containing and supporting a stimulable phosphor in a dispersed state. A radiation image detection method according to claim 1. 4. The method according to any one of claims 1 to 3, wherein the stimulable phosphor is a divalent europium-activated alkaline earth metal fluorohalide phosphor. Radiographic image detection method.