JPH02275586A - Method and device for reading radiation image information - Google Patents

Abstract

PURPOSE:To conversationally determine a proper radiation image information reading condition/image processing condition at the time of obtaining a visual image by displaying a radiation image charged by a monitor image signal on an image display means as a monitor image and executing the conversion processing of a monitor image signal. CONSTITUTION:The device is basically constituted of a radiation image photographing part 20, a reading part 30 for prereading, a reading part 40 for real reading, and an image reproducing part 50. In the case of determining the reading condition/image processing condition based upon data for determining the density/contrast of a monitor image, a control part 314 corrects the data so that the non-linear property of display density characteristic to an input signal to a monitor image display means 354 is corrected. Or, the data are corrected by the control part 314 for an image signal to be inputted to the image display means 354. When the display density/contrast of the monitor image is adjusted at its optimum, the radiation image to be reproduced can be reproduced with the same optimum density/contrast.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method for reading radiographic image information from a recording medium in which the image information is recorded as an electrical image signal, and more particularly, to converting the image signal into a visible image. Before the reproduction, a monitor image is displayed based on the monitor image signal indicating the radiation image information, and while observing the monitor image, the radiation image information reading conditions and/or image processing conditions are determined during visible image reproduction. The present invention relates to a radiation image information reading method that enables appropriate determination of information, and an apparatus for implementing the method.

(Prior art) When a certain type of phosphor is irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated in the phosphor, and this It is known that when a phosphor is irradiated with excitation light such as visible light, the phosphor exhibits stimulated luminescence depending on the accumulated energy, and phosphors that exhibit this property are called stimulable phosphors. .

Using this stimulable phosphor, radiation image information of the human body, etc. is temporarily recorded on a stimulable phosphor sheet, and this stimulable phosphor sheet is scanned with excitation light such as a laser beam to generate stimulated luminescence light. The resulting stimulated luminescent light is read photoelectrically to obtain an image signal, and based on this image signal, one radiation image is output as a visible image to a recording material such as a photographic light-sensitive material or a display device such as a CRT. A radiation image information recording and reproducing system has already been proposed by the present applicant (Japanese Unexamined Patent Publication No. 124-1989).
No. 92, No. 513-11395, etc.).

In the above system, in order to eliminate the influence of fluctuations in imaging conditions or to obtain radiation images that are suitable for observation and interpretation, it is necessary to change the recording state of the radiation image information accumulated and recorded on the stimulable phosphor sheet, as well as the chest and abdomen. Visual images for observation and interpretation of recorded patterns (hereinafter collectively referred to as "accumulated recorded information") determined by the body part of the subject, the imaging method such as plain radiography, contrast radiography, etc. The system determines the recording scale factor so that the resolution is optimized according to the contrast of the recording pattern, and the reading gain is adjusted to an appropriate value based on the acquired accumulated recording information. It is necessary.

A method disclosed in Japanese Patent Laid-Open No. 58-67240 is known as a method of grasping accumulated recorded information prior to outputting a visible image. This method uses excitation light of a lower level than the excitation light that should be irradiated during the reading operation (hereinafter referred to as "main reading") to obtain a visible image for observation and interpretation, and is accumulated in advance prior to the main reading. A reading operation (hereinafter referred to as "pre-reading") is performed to grasp the accumulated record information of one radiographic image accumulated and recorded on the phosphor sheet, thereby grasping an overview of the accumulated record of the radiographic image, and then the main reading. When performing this, the reading gain is appropriately adjusted, the recording scale factor is determined, or the signal processing conditions are determined based on this pre-read information.

According to the above method, the recording state and recording pattern of the radiation image information accumulated and recorded on the stimulable phosphor sheet can be known in advance before the actual reading, so the reading gain can be adjusted appropriately based on this recorded information. By adjusting the recording pattern, determining the recording scale factor, and applying signal processing to the electrical signals after reading according to this recording pattern, it becomes possible to obtain a radiographic image with excellent suitability for observation and interpretation.

Furthermore, in Japanese Patent Laid-Open No. 03-183434, for example, the applicant omitted the above-mentioned pre-reading and grasped the outline of accumulated recorded information from the image signal obtained in one reading process, and when reproducing a visible image, A method has also been proposed in which conditions for image processing to be applied to the image signal or conversion processing equivalent to changing reading conditions are determined based on accumulated record information ascertained as described above.

This method of determining conditions for image processing, etc. can also be used when obtaining electrical image signals by reading radiographic image information with a microphotometer etc. from conventionally used silver halide photographic film for X-ray photography. , is similarly applicable.

By the way, the reading conditions and/or image processing (including conversion processing equivalent to changing the reading conditions described above) of radiation image information is performed based on the above-mentioned pre-read image signal or the image signal used for reproducing a visible image. When determining the conditions for reading, if a special substance is imprinted in the radiation image, the determined reading conditions and image processing conditions may be
It is possible that it may not necessarily be the optimal one for observing the subject. As a method to deal with such problems, a radiation image is displayed in advance as a monitor image by inputting a pre-read image signal or an image signal used for visible image reproduction into an image display means such as a CRT. By converting the image signal used for monitor image display (this is called the monitor image signal),
The density and/or contrast of the monitor image can be adjusted, and the method for obtaining the visible image is based on data showing the characteristics of the conversion process when a monitor image with appropriate density and/or contrast is obtained. A possible method is to determine radiation image information reading conditions and/or image processing conditions (for example, Japanese Patent Application No. 83-21
No. 2231).

(Problem to be Solved by the Invention) According to the above method, the density and/or contrast of the monitor image can be freely set in an interactive manner by making adjustments while observing the monitor image. If there is a proper correspondence between the data that determines the conversion processing characteristics of the image signal and the reading conditions and/or image processing conditions for visible image reproduction, radiation of the same density and/or contrast as the monitor image will be produced. This means that the image can be reproduced as a visible image.

However, in reality, when comparing a monitor image and a visible image reproduced based on it, for example, the density in the low density area is the same in both images, but the density in the high density area is different in both images.
It was found that problems such as these were likely to occur.

Therefore, the present invention solves the above-mentioned problems and provides a radiation image information reading method that can interactively determine appropriate radiation image information reading conditions and/or image processing conditions when obtaining a visible image. , and an apparatus for implementing the method.

(Means and effects for solving the problem) The present invention provides CR
This was done based on the knowledge that in image display means such as T-types, the input signal versus display density characteristic is often not linear, and this is the cause of the above-mentioned problems. The first radiation image information reading method of the invention obtains an image signal by extracting radiation image information from a recording medium in which the radiation image information is recorded as described above, and converts this image signal into a linear input signal pair. When inputting the reproduction density characteristics to an image reproduction means and reproducing the radiation image as a visible image based on No. 15, a monitor image signal indicating the radiation image information is obtained, and this monitor image signal is The density and/or contrast of the monitor image can be adjusted by displaying the radiographic image on the image display means as a monitor image, and converting the monitor image signal, so that the monitor image has an appropriate density and/or contrast. The radiation image information reading conditions and/or image processing conditions for obtaining the visible image are determined based on the data indicating the characteristics of the conversion process when the visible image is obtained, and at that time, the data is displayed on the image display means. After correcting the non-linearity of the input signal versus display density characteristic of the monitor and converting it to obtain the above-mentioned visible image with approximately the same density and/or contrast as the monitor image, the reading conditions and/or image processing conditions are determined. It is characterized by its use.

Furthermore, in the second radiation image information reading method of the present invention, instead of correcting the data indicating the conversion processing characteristics in the first method, a monitor image signal input to the image display means is input to the image display means. This method is characterized by performing conversion processing to correct nonlinearity of signal versus display density characteristics.

The present invention also provides a radiographic image information reading device for carrying out the above-described method. , a main reading reading means for reading radiation image information from a recording medium on which the radiation image information is recorded to obtain an image signal, and a monitoring reading means for reading radiation image information from the recording medium to obtain a monitoring image signal. , storage means for storing the monitor image signal; image display means for receiving the monitor image signal read from the storage means and displaying the image carried by the signal as a monitor image; Signal converting means for converting the monitor image signal so as to change the contrast; input means for inputting data for determining conversion characteristics of the converting process to the signal converting means; and reading means for main reading. a condition determining means for determining radiation image information reading conditions and/or image processing conditions when reproducing the radiation image as a visible image based on the image signal obtained from the image, based on the data received from the input means; The above data inputted into this condition determining means,
It is characterized by being equipped with a data correction function that corrects the non-linearity of the input signal versus display density characteristic of the image display means and converts it so as to obtain the visible image with approximately the same density and/or contrast as the monitor image. That is.

Further, a second radiation image information reading device according to the present invention is for implementing the second method, and a data correction function is added to the condition determining means in the first radiation image information reading device described above. Instead, an image signal correction means is provided for converting the monitor image signal input to the image display means so as to correct the nonlinearity of the input signal versus display density characteristic of the image display means. It is something to do.

Further, the third radiographic image information reading device according to the present invention is also for implementing the second method, and includes adding a data correction function to the condition determining means in the first radiographic image information reading device described above. Instead, the conversion characteristic of the signal conversion means for converting the monitor image signal so as to change the density and/or contrast of the monitor image is adjusted to correct the nonlinearity of the input signal versus display density characteristic of the image display means. The present invention is characterized in that it is provided with conversion characteristic correction means for converting into.

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

FIG. 1 shows a radiation image information recording and reproducing system equipped with a radiation image information reading device according to a first embodiment of the present invention. This radiation image information recording and reproducing system basically includes a radiation image capturing section 20, a prefetch reading section 30,
The main reading reading section 40 and the image Ig! It is composed of a reproduction section 50. In the radiographic imaging unit 20, a subject (subject) 1 is emitted from a radiation source 100 such as an X-ray tube, for example.
Radiation 102 is irradiated toward 01. The position where the radiation 102 that has passed through the subject 101 is irradiated is as follows:
As described above, the stimulable phosphor sheet 103 that accumulates radiation energy is arranged, and the stimulable phosphor sheet 10
3, transmitted radiation image information of the subject 101 is stored and recorded.

The stimulable phosphor sheet 103 on which the radiation image information of the subject 101 has been recorded in this manner is sent to the pre-reading reading section 30 by sheet transport means 110 such as a transport roller. In the pre-reading reading section 30, the pre-reading laser light source 2
The laser beam 202 emitted from the laser beam 2
A filter 2 that cuts the wavelength range of stimulated luminescence light emitted from the stimulable phosphor sheet 103 by excitation of 02
03, the light is linearly deflected by a light deflector 204 such as a galvanometer mirror, and is incident on the stimulable phosphor sheet 103 via a flat reflecting mirror 205. Here, the laser light source 201 is selected so that the wavelength range of the laser light 202 as excitation light does not overlap with the wavelength range of the stimulated luminescence light emitted by the stimulable phosphor sheet 103. On the other hand, the phosphor sheet 103 is moved by a sheet transport means 21 such as a transport roller.
0, the phosphor sheet 103 is moved in the direction of the arrow 206 for sub-scanning, and as a result, the entire surface of the phosphor sheet 103 is irradiated with the laser light 202. Here, the emission intensity of the laser light source 201, the beam diameter of the laser light 202, the laser light 202
The scanning speed of the stimulable phosphor sheet 103 and the transport speed of the stimulable phosphor sheet 103 are as follows.
The energy of the excitation light (laser light 202) for pre-reading is selected to be smaller than that for main reading performed in the main reading reading unit 40, which will be described later.

When irradiated with the laser beam 202 as described above, the stimulable phosphor sheet 103 emits stimulated luminescent light with an amount corresponding to the radiation energy stored and recorded therein, and this luminescent light is transmitted to the pre-reading light guide 207. incident on . The stimulated luminescence light is guided through the light guide 207, exits from the exit surface, and is received by a photodetector 208 such as a photomultiplier. A filter is attached to the light-receiving surface of the photodetector 208, which transmits only light in the wavelength range of stimulated luminescence light and cuts light in the wavelength range of excitation light, and detects only stimulated luminescence light. It is now possible to do so. The detected stimulated luminescence light is converted into an electrical signal carrying accumulated recording information, and is sent to an amplifier 2.
09. The signal output from the amplifier 209 is digitized by the A/D converter 211 and sent to the control unit 314 of the main reading reading unit 40 as a pre-read image signal Sp.
is input. This control unit 314 controls the prefetch image signal S
Based on the accumulated record information indicated by p, read gain setting IS
k, determine the recording scale factor setting value Gp. In addition, these setting values S! <Determination of SGp will be described later.

The stimulable phosphor sheet 103 whose pre-reading has been completed as described above is transferred to the reading section 40 for main reading.

In the main reading reading section 40, the main reading laser beam 111X
A laser beam 302 emitted from a laser beam 301 passes through a filter 303 that cuts the wavelength range of stimulated luminescence light emitted from a stimulable phosphor sheet 103 by excitation of the laser beam 302, and then is expanded into a beam by a beam expander 304. The size of the diameter is strictly adjusted, and the light from a galvanometer mirror (- is linearly deflected by the internal device 305 and transmitted through the stimulable phosphor sheet 103 via the flat reflector 306.
incident on the top. An fθ lens 307 is disposed between the optical deflector 305 and the plane reflecting mirror 30B, so that the beam diameter of the laser beam 302 scanning the stimulable phosphor sheet 103 is made uniform. On the other hand, the stimulable phosphor sheet 10
3 is transported in the direction of arrow 308 by a sheet transport means 320 such as a transport roller to perform sub-scanning, and as a result,
``The entire surface of the stimulable phosphor sheet lO3 is irradiated with laser light. When irradiated with the laser beam 302 in this manner, the stimulable phosphor sheet 103 emits stimulated luminescence light with an amount corresponding to the radiation energy stored and recorded therein, and this luminescent light enters the main reading light guide 309. do.

Stimulated luminescent light guided through the main reading light guide 309 while undergoing repeated total reflection is emitted from its exit surface and is received by a photodetector 31O such as a photomultiplier.

A filter that selectively transmits only the wavelength range of the stimulated luminescence light is attached to the light receiving surface of the photodetector 310.
10 detects only stimulated luminescence light.

The output of the photodetector 31O, which photoelectrically detects the stimulated luminescent light representing the radiation image recorded on the stimulable phosphor sheet 103, has a read gain based on the read gain setting value Sk determined by the control section 314. The electric signal is amplified to an appropriate level by the amplifier 311 set to . The amplified electrical signal is input to the A/D converter 312, and based on the recording scale factor setting value Gp, it is converted into a digital signal with a recording scale factor suitable for the signal fluctuation width, and the digital signal is input to the signal processing circuit 313. . The digital signal is subjected to signal processing (image processing) in this signal processing circuit 313 so as to obtain a radiation image excellent in suitability for observation and interpretation.
and output.

The read image signal (actual read image signal) So output from the signal processing circuit 313 is transmitted to the optical modulator 401 of the image reproducing unit 50.
is input. In this image reproducing unit 50, a laser beam 403 from a recording laser light source 402 is transmitted to an optical modulator 40.
1, the main reading image signal Sol: inputted from the Z processing circuit 313 is modulated, deflected by the scanning mirror 404, and scanned on a photosensitive material 405 such as a photographic film.Then, the photosensitive material 405 is The radiation image is transferred in synchronization with the scanning in a direction perpendicular to the scanning direction (arrow 40G direction), and a radiation image based on the actual reading image signal So is output onto the photosensitive material 405.As a method for reproducing the radiation image, In addition to this method, various methods such as display using a CRT can be adopted.As in many image recording devices, the photosensitive material 40
The characteristic of the density of the radiation image recorded in 5 and the image signal So is linear.

Next, regarding the determination of the reading gain setting value Sk and recording scale factor setting value cp in the control unit 314,
The control section 314 will be explained in detail with reference to FIG. 2. The pre-read image signal Sp is stored in the memory 351 as a monitor image signal.

Pre-read image signal Sp read out from this memory 351
is passed through the table converter 352, where it undergoes conversion processing to be described later and is converted into an image signal Sc.

This image signal Sc is passed through a D/A converter 353 to be converted into an analog signal, and then sent to an image display means 35 such as a CRT.
4 is input. This image display means 354 displays the image carried by the image signal Sc, that is, the radiation image stored and recorded on the stimulable phosphor sheet 103.

The table converter 352 receives table data S from the input means 355, and the table converter 352 converts the pre-read image signal Sp as described above according to the conversion table formed based on the table data St. The characteristics of this conversion table are, for example, as shown in FIG. , and the center density (luminance) corresponds to the signal value at the center of the width W.The input child actor 355 stores data responsible for the basic characteristics as shown in the m5 diagram above. According to the basic data and the above-mentioned WSL value inputted by the operator, data St of the conversion table set in the table converter 352 is created and output.Therefore, the contrast of the monitor image displayed on the image display means 354 and The center density changes accordingly if the operator changes the values of W and L inputted into the input means 355. Therefore, the operator changes the values of W and L as appropriate without observing the monitor image. As a result, a radiation image with the most preferable contrast and density can finally be displayed on the image display means 354.The values of W and L used to obtain this most preferable radiation image can be transferred by the operator. According to the command, the information is transferred to the condition determining section 35B.

W and L input into the condition determination unit 356 as described above
, that is, the values of W and L when an image with optimal density and contrast is displayed on the image display means 354, read gain 5k-f (L), recording scale factor Gp = g (W) [f and g are linear functions for correcting the difference in density and contrast between the image display means 354 and the image reproduction/recording means 50, respectively] If so, originally, the image reproduction section 50 would use the photosensitive material 405.
The density and contrast of radiographic images reproduced and recorded should also be optimal. However, since the input signal versus display density characteristic of the image display means 354 such as a CRT is non-linear, this is not actually the case. That is, for example, it is assumed that the pre-read image signal Sp is converted into the signal Sc with the characteristic A shown in FIG. Assuming characteristic C, when the value of the pre-read image signal Sp is any N (that is, the signal Sc
When the value of So is 81, the display density is D], whereas when the image signal So is 81, the reproduced density on the photosensitive material 405 is D1. To deal with this, the condition determining unit 3
5B determines the signal value Sn for obtaining the reproduced density D1 based on the inverse function of the characteristic C given in advance and the characteristic B;
Find the point (N, Sn). In addition, the condition determination unit 35 [i similarly performs the same processing on another arbitrary pre-read image signal value M to obtain the point (M, Sm), and calculates these points (N, Sn) and (M, The characteristic represented by the line segment A' passing through Sm) is determined. Then, the condition determining unit 35G determines Slc -f based on the width W' of the linear portion in this characteristic A' and the central signal 1fi L' therein.
(L') and Gp=g (W'), the reading gain setting value S Ic and the recording scale factor setting value cp are determined. If the reading conditions are determined in this way, the nonlinear characteristics of the image display means 354 are corrected so that the displayed density thereof and the reproduced density on the photosensitive material 405 roughly match over almost the entire density range. Become.

Next, referring to FIG. 3, a second embodiment of the present invention will be described. This FIG. 3 shows a control section 314A used in the system of FIG. 1 instead of the control section 314 shown in FIG.
It shows. Note that in FIG. 3, elements equivalent to those shown in FIGS. 1 and 2 are given the same numbers, and explanations thereof will be omitted unless particularly necessary (the same applies hereinafter).

This 17! The condition determination unit 360 of the I control unit 314A is
Unlike the condition determination section 35G of the device shown in the figure, the image display means 3
It does not have a function to correct the nonlinearity of 54, but simply uses the table data St input to the table converter 352 to calculate the reading gain 5k-f (L) and the recording scale factor Gp-g (W). Find the setting value of the condition.

On the other hand, the image signal S after being converted by the table converter 352
c is calculated by another correction table converter 361,
The signal undergoes conversion processing to correct the nonlinearity of the image display means 354, and is input to the D/A converter 353 as a signal Sc'. The conversion characteristic of the correction table converter 361 is as shown by curve E in FIG. 7, that is, the reverse of the input signal versus display density characteristic B of the image display means 354. . When subjected to such conversion, the relationship between the pre-read image signal Sp and the display density becomes as shown by F in the figure, and the density characteristic of the pre-read image signal Sp versus the display density becomes linear. Therefore, the conversion characteristic A (i.e., the value of WI:!:L) when a monitor image is displayed with a certain density and contrast in the image display means 354
The reproduced radiation image obtained by determining the reading gain 5k-f (L) and recording scale factor Gp-g (W) based on the above has the same density and contrast as the monitor image. Therefore, when the density and contrast of the monitor image are optimal, the condition determining section 356 should determine the reading gain Sk and recording scale factor cp based on the obtained table data St (that is, @ of W and L). , the density and contrast of the reproduced radiation image are also optimized.

Note that the conversion characteristic E of the correction table converter 3GL is determined by the table data Sv input from the input means 362. Therefore, if the input signal versus display density characteristic of the image display means 354 changes, by re-inputting the table data Sv accordingly, the nonlinearity of the characteristic can always be corrected accurately.

Next, referring to FIG. 4, a third embodiment of the present invention will be described. This FIG. 4 also shows a control section 314B used in place of the control section 314 shown in FIG. Table data correction section 370 used in this control section 314B
converts the table data St sent from the input means 355 according to the table data Sv sent from the input means 362, and sends the converted table data to the table converter 352. That is, the characteristics of the conversion table set in this table converter 352 are a combination of characteristics A and E, if explained using diagram m7. By using such a conversion table, the same nonlinearity correction effect as in the second embodiment can be obtained in this embodiment as well.

The apparatus shown in FIG. 1 has separate reading sections for main reading and reading sections for pre-reading.
As shown in No. 07242, the reading system for main reading and the reading system for pre-reading are used together, and when the pre-reading is completed, the stimulable phosphor sheet is returned to the reading system by the sheet transport means and the main reading is performed. The excitation light energy may be adjusted by the light energy adjustment means so that it is smaller than that during main reading, and the method of the present invention is also applicable to the case where radiation image information is read by such an apparatus.

Furthermore, in the embodiments described above, the read condition for radiation image information is determined by displaying the monitor image using the pre-read image signal. Conditions and/or
Alternatively, it is of course possible to determine image processing conditions.

The present invention can also be applied to reading radiation image information recorded on silver salt photographic films for X-ray photography other than stimulable phosphor sheets.

In that case, the image signal obtained by reading the radiation image with a microphotometer etc. is displayed on a monitor image, and while observing the monitor image, appropriately determine the image processing conditions equivalent to changing the reading conditions, for example. I can do it.

(Effects of the Invention) As described in detail above, in the present invention, when determining reading conditions and/or image processing conditions based on data that determines the density and/or contrast of a monitor image, input to the monitor image display means is Since the above data is corrected to correct the non-linearity of the signal versus display density characteristic, or the image signal input to the image display means is corrected, the display density and/or contrast of the monitor image can be optimized. Once adjusted, the reproduced radiographic image will be reproduced with the same optimal density and/or contrast. Therefore, according to the present invention, it is possible to obtain radiographic images with high diagnostic performance through simple operations without requiring special skill.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing a radiographic image information reading device according to the first embodiment of the present invention, and Figs. 2.3 and 4 show the main parts of the apparatus according to the 1.2 and 3 embodiments of the present invention, respectively. A block diagram, FIG. 5 is a graph showing the characteristics of the conversion processing of a monitor image signal according to the present invention, FIG. 6 is an explanatory diagram explaining the first method of the present invention, and FIG. It is an explanatory diagram explaining a method. 20...Radiation image capturing unit 30...Reading unit for pre-reading 40...Reading unit for main reading 100...
Radiation source 101...Subject 102...
- Radiation 103...Stormable phosphor sheet 104...
Aperture 201... Laser light source for pre-reading 202... Laser light for pre-reading 204... Optical deflector for pre-reading 208... Photodetector for pre-reading 210... Sheet transport means for pre-reading 301... For main reading Laser light source 302...Laser light for main reading 305...Light deflector for main reading 310...Photodetector for main reading 311...Amplifier 3[2...A/D conversion 2''J 313...
Signal processing circuits 314, 314 A, 314 B...
Control unit 320... Main reading sheet transport means 351... Memory 352, 301... Table converter 353... D/A converter 354...
Image display means 355.3G2...Input means 35G, 300...Condition determination section 370...Table data correction section k...Reading gain setting value p...Recording scale factor setting value 0...Main reading Image signal Sp...Pre-read image signal tSSV...Table data c, Sc'...Converted pre-read image signal Relationship between radiographic image information reading method A3 and the case of the person who corrects the device

Claims (5)

[Claims] (1) Obtain an image signal by reading radiographic image information from a recording medium on which radiographic image information is recorded, input this image signal to an image reproducing means having a linear input signal versus reproduction density characteristic, and convert the image signal into When reproducing a radiographic image as a visible image based on the radiographic image information, a monitor image signal indicating the radiographic image information is obtained, a radiographic image carried by this monitor image signal is displayed as a monitor image on an image display means, and the monitor image signal is displayed as a monitor image on an image display means. By converting the image signal, the density and/or contrast of the monitor image can be adjusted, and the density and/or contrast is based on data indicating the characteristics of the conversion process when an appropriate monitor image is obtained. determining radiation image information reading conditions and/or image processing conditions for obtaining the visible image; at this time, correcting the data for non-linearity of the input signal versus display density characteristic of the image display means; A radiation image information reading method characterized in that the visible image is converted to obtain the visible image with substantially the same density and/or contrast as the monitor image, and then used for determining the reading conditions and/or image processing conditions. (2) Obtain an image signal by reading the radiographic image information from a recording medium on which the radiographic image information is recorded, input this image signal to an image reproducing means having a linear input signal versus reproduction density characteristic, and convert the image signal into When reproducing a radiographic image as a visible image based on the radiographic image information, a monitor image signal indicating the radiographic image information is obtained, a radiographic image carried by this monitor image signal is displayed as a monitor image on an image display means, and the monitor image signal is displayed as a monitor image on an image display means. By converting the image signal, the density and/or contrast of the monitor image can be adjusted, and the density and/or contrast is based on data indicating the characteristics of the conversion process when an appropriate monitor image is obtained. determining radiation image information reading conditions and/or image processing conditions when obtaining the visible image, and at that time, correcting the monitor image signal for nonlinearity in the input signal versus display density characteristic of the image display means. A radiation image information reading method characterized in that the radiation image information is inputted to the image display means after being converted so that the information is converted into the image. (3) reading means for reading the radiation image information from a recording medium on which the radiation image information is recorded to obtain an image signal; and reading means for reading the radiation image information from the recording medium to obtain an image signal for monitoring. a reading means, a storage means for storing the monitor image signal, and a monitor image signal read out from the storage means;
an image display means for displaying an image carried by the signal as a monitor image; a signal conversion means for converting the monitor image signal so as to change the density and/or contrast of the monitor image; an input means for inputting data that determines conversion characteristics of processing, and radiation image information reading conditions and/or image processing conditions when reproducing a radiation image as a visible image based on the image signal obtained by the main reading reading means. and condition determining means for determining the data based on the data received from the input means, and the condition determining means determines the data input thereto,
A data correction function is provided for correcting the non-linearity of the input signal versus display density characteristic of the image display means to obtain the visible image having approximately the same density and/or contrast as the monitor image. Characteristic radiation image information reading device. (4) reading means for reading the radiographic image information from a recording medium on which the radiographic image information is recorded to obtain an image signal; and a reading means for reading the radiographic image information from the recording medium to obtain an image signal for monitoring. a reading means, a storage means for storing the monitor image signal, and a monitor image signal read out from the storage means;
an image display means for displaying an image carried by the signal as a monitor image; a signal conversion means for converting the monitor image signal so as to change the density and/or contrast of the monitor image; an input means for inputting data that determines conversion characteristics of processing, and radiation image information reading conditions and/or image processing conditions when reproducing a radiation image as a visible image based on the image signal obtained by the main reading reading means. a condition determining means for determining the monitor image signal inputted to the image display means based on the data outputted by the input means; A radiation image information reading device comprising an image signal correction means for converting to correct it. (5) reading means for main reading that reads radiographic image information from a recording medium on which radiographic image information is recorded and obtains an image signal; and reading means for reading the radiographic image information from the recording medium and obtains an image signal for monitoring. a reading means, a storage means for storing the monitor image signal, and a monitor image signal read out from the storage means;
an image display means for displaying an image carried by the signal as a monitor image; a signal conversion means for converting the monitor image signal so as to change the density and/or contrast of the monitor image; an input means for inputting data that determines conversion characteristics of processing, and radiation image information reading conditions and/or image processing conditions when reproducing a radiation image as a visible image based on the image signal obtained by the main reading reading means. a condition determining means for determining the above data based on the data outputted by the input means; and converting the conversion characteristic of the signal converting means so as to correct the non-linearity of the input signal versus display density characteristic of the image display means. A radiation image information reading device comprising conversion characteristic correction means.