JP2023076350A - Reading device - Google Patents

Abstract

To provide a technique that makes it possible to properly evaluate the image quality of a radiological image read out from an imaging plate.SOLUTION: A reading device for reading a radiological image from an imaging plate includes a light source that irradiates an imaging plate with excitation light and a first detector that detects light emitted from the imaging plate by the excitation light and outputs a first image signal as a detection result of the emitted light. The light source irradiates an evaluation member having an evaluation pattern on the front surface based on the first image signal for evaluating the image quality of the detected radiological image. The reading device further includes a second detector that detects reflected light of the excitation light from the surface of the evaluation member and outputs a second image signal as a detection result of the reflected light.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to reading devices.

Patent Document 1 describes a technique for reading image information from a stimulable phosphor sheet.

JP-A-61-267451

The image quality of the radiation image read from the imaging plate may be evaluated.

Accordingly, an object of the present disclosure is to provide a technique capable of appropriately evaluating the image quality of a radiographic image read from an imaging plate.

A reading device according to a first aspect is a reading device for reading a radiation image from an imaging plate, comprising a light source for irradiating the imaging plate with excitation light, and detecting light emitted from the imaging plate by the excitation light, and a first detector that outputs a first image signal as a detection result of the emitted light, wherein the light source provides an evaluation pattern for image quality evaluation of the detected radiation image based on the first image signal. The evaluation member on the surface is irradiated with the excitation light, the reflected light of the excitation light from the surface of the evaluation member is detected, and a second image signal is output as a detection result of the reflected light. 2 detectors.

A reading device according to a second aspect is the reading device according to the first aspect, wherein the first detector functions as the second detector, and the first detector serves as the emitted light. and the reflected light.

A third aspect is the reading device according to the first or second aspect, wherein the evaluation pattern is printed on the surface of the evaluation member.

A fourth aspect is the reading device according to the third aspect, wherein the member for evaluation is printed paper.

A fifth aspect is the reading device according to any one of the first to fourth aspects, which displays a reflected light image based on the second image signal.

According to the first aspect, the image quality of the detected radiation image, that is, the radiation image read from the imaging plate is appropriately evaluated based on the image of the evaluation pattern included in the reflected light image based on the second image signal. be able to.

According to the second aspect, the configuration of the reader can be simplified because the first detector functions as the second detector.

According to the third aspect, since the evaluation pattern is created by printing, it is possible to obtain a highly accurate evaluation pattern. Therefore, image quality evaluation of the detected radiation image can be performed more appropriately.

According to the fourth aspect, since the evaluation member is printed paper, it is possible to evaluate the image quality of the detected radiation image using an inexpensive evaluation member.

According to the fifth aspect, the user can check the image of the evaluation pattern included in the reflected light image based on the second image signal to evaluate the image quality of the detected radiation image.

It is a schematic diagram showing an example of the appearance of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a block diagram which shows an example of a structure of a reading device. It is the schematic which shows an example of an IP existence area, an excitation light irradiation range, and a detection range. It is the schematic which shows an example of an IP existence area, an excitation light irradiation range, and a detection range. It is the schematic which shows an example of an IP existence area, an excitation light irradiation range, and a detection range. FIG. 4 is a schematic diagram showing an example of an acquisition overview; FIG. 4 is a schematic diagram showing an example of an acquisition overview; FIG. 4 is a schematic diagram showing an example of an acquisition overview; FIG. 4 is a schematic diagram showing an example of an acquisition overview; 4 is a flow chart showing an example of the operation of the reading device; FIG. 4 is a schematic diagram showing an example of how the imaging plate is tilted; FIG. 4 is a schematic diagram showing an example of an acquisition overview; It is a schematic diagram for explaining an example of inclination angle identification processing. It is a schematic diagram for explaining an example of inclination angle identification processing. It is a schematic diagram for explaining an example of size identification processing. It is a figure which shows an example of the size of an imaging plate, and an inclination angle. It is a figure which shows an example of the size of an imaging plate, and an inclination angle. FIG. 4 is a diagram showing an example of types of sizes of imaging plates; 4 is a flow chart showing an example of the operation of the reading device; 4 is a flow chart showing an example of the operation of the reading device; FIG. 4 is a schematic diagram showing an example of an acquisition overview; FIG. 4 is a schematic diagram showing a display example of an acquired overall image; FIG. 4 is a schematic diagram showing a display example of an acquired overall image; It is a figure which shows an example of the size of an imaging plate, and an inclination angle. FIG. 5 is a schematic diagram for explaining an example of tilt correction processing; FIG. 4 is a schematic diagram showing an example of an acquisition overview; It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram showing an example of a cut-out image. It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram showing an example of a cut-out image. FIG. 4 is a schematic diagram showing a display example of a cut-out image; It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram showing an example of a cut-out image. It is a schematic diagram showing an example of a cut-out image. It is a schematic diagram showing an example of a structure of a holding part. FIG. 4 is a schematic diagram showing an example of an acquisition overview; It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram showing an example of a cut-out image. FIG. 4 is a schematic diagram showing an example of an acquisition overview; It is a schematic diagram for explaining an example of a clipping process. It is a schematic diagram showing an example of a cut-out image. It is a schematic diagram showing an example of a cut-out image. FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; FIG. 11 is a schematic diagram showing a display example of non-exposure notification information; It is the schematic which shows an example of the member for evaluation. It is the schematic which shows an example of the member for evaluation. It is the schematic which shows an example of the member for evaluation. It is the schematic which shows an example of the member for evaluation. 4 is a flow chart showing an example of the operation of the reading device; It is a schematic diagram showing an example of an overview for evaluation. It is a schematic diagram showing an example of an overview for evaluation. It is a schematic diagram showing an example of an overview for evaluation. It is a schematic diagram showing an example of an overview for evaluation. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device. It is a schematic diagram showing an example of a configuration of a reading device.

FIG. 1 is a schematic diagram showing an example of the appearance of the reader 1. As shown in FIG. The reader 1 is a device that reads a radiographic image from an imaging plate 10 on which the radiographic image is recorded. It can also be said that the reader 1 is a device that detects a radiation image recorded on the imaging plate 10 .

The imaging plate 10 has a flat shape having a radiation image forming layer 11 and is a recording medium for recording radiation images. The imaging plate 10 has, for example, a substantially rectangular flat shape with rounded corners. The radiation image forming layer 11 is a layer that accumulates energy of irradiated radiation and emits light according to the accumulated energy. For example, the radiation image forming layer 11 is formed by applying a stimulable phosphor to one main surface of a film made of resin. As the radiation with which the radiation image forming layer 11 is irradiated, for example, X-rays are employed. When the X-rays from the X-ray generator pass through the object to be imaged and are irradiated onto the imaging plate 10 , energy corresponding to the intensity of the X-rays is accumulated in the radiation image forming layer 11 . Since the X-ray intensity is based on the distribution of the X-ray absorption regions in the object to be imaged, the distribution of the energy accumulated in the radiation image forming layer 11 is the radiographic image of the object to be imaged by X-rays. In this way, the imaging plate 10 records, for example, an X-ray radiation image as a latent image. The reader 1 reads a radiographic image from the radiographic image forming layer 11 and generates an image signal (also referred to as image data) representing the read radiographic image.

In this example, the imaging plate 10 is exposed to radiation while it is placed in, for example, a person's mouth. Therefore, the imaging plate 10 is sized to fit inside a person's mouth. For example, a radiographic image of teeth is recorded on the radiographic image forming layer 11 of the imaging plate 10 . Note that the application of the imaging plate 10 is not limited to this.

Hereinafter, in the imaging plate 10, the main surface on the side of the radiation image forming layer 11 may be referred to as the front surface. Also, in the imaging plate 10, the main surface opposite to the front surface may be called the back surface.

As shown in FIG. 1, the reading device 1 comprises a housing 2, for example. A structure for reading a radiographic image from the imaging plate 10 is accommodated in the housing 2 . The configuration will be described later.

The housing 2 is provided with an insertion port 2a and an extraction port 2b. The insertion port 2a is provided on the upper surface of the housing 2, for example. A user of the reader 1 can insert the imaging plate 10 into the housing 2 through the insertion port 2a. A radiation image is read from the imaging plate 10 within the housing 2 . The outlet 2b is provided, for example, in a lower portion of one side surface of the housing 2. As shown in FIG. The imaging plate 10 after the radiographic image has been read (also referred to as the read imaging plate 10) is ejected through the outlet 2b. A user of the reader 1 can collect the read imaging plate 10 through the outlet 2b.

In this example, the reader 1 can erase the radiographic image from the imaging plate 10 after reading the radiographic image from the imaging plate 10 . For example, the imaging plate 10 from which the radiographic image has been erased is discharged from the outlet 2b.

The housing 2 is provided with, for example, an operation unit 4 that receives operations from the user. The operation unit 4 includes, for example, a plurality of operation buttons 4a. Each operation button 4a is, for example, a hardware button. The plurality of operation buttons 4a include, for example, a power button and a start button for instructing the start of reading. The operation unit 4 may include a touch sensor that detects a user's touch operation.

The housing 2 is provided with, for example, a display section 3 . The display unit 3 is configured by, for example, a liquid crystal display panel or an organic EL (electro-luminescence) display panel. The display unit 3 can display various information such as characters, symbols, graphics, and images. The display unit 3 may display a radiographic image read from the imaging plate 10 (in other words, a detected radiographic image).

When the operation unit 4 includes a touch sensor, the touch sensor and the display unit 3 may constitute a touch panel display having a display function and a touch detection function. In this case, at least one of the plurality of operation buttons 4a may be replaced with a software button displayed on the touch panel display, and the operation section 4 may not include the plurality of operation buttons 4a. Further, the reading device 1 does not have to include the display section 3 .

The housing 2 is provided with plate housing cases 6 and 7 capable of housing the imaging plate 10, for example. The plate housing cases 6 and 7 are provided on the upper surface of the housing 2, for example. The plate storage case 6 is a case with a partition, and the plate storage case 7 is a case with a lid. At least one of the plate housing cases 6 and 7 does not have to be provided at the reading device 1 .

A cable 5 a of an AC adapter 5 extends outward from the housing 2 . Power is supplied from an AC adapter 5 to each component of the reading device 1 . The reader 1 may include not only the AC adapter 5 but also a battery that supplies power to each component of the reader 1 . Alternatively, the reader 1 may have a battery instead of the AC adapter 5 .

<About an example of the mechanism in the housing>
2 to 5 are schematic diagrams showing an example of the internal configuration of the housing 2. FIG. FIG. 3 is a schematic diagram showing an example of a cross-sectional structure taken along line AA in FIG. FIG. 4 is a schematic diagram showing an example of a cross-sectional structure taken along line BB in FIG. FIG. 6 is a block diagram mainly showing an example of the configuration of the control section 80 provided in the reading device 1. As shown in FIG. As will be described later, the holding section 20 that holds the imaging plate 10 can move in the housing 2 along the predetermined direction DR10. FIG. 3 shows how the imaging plate 10 and the holder 20 have moved from the state shown in FIG.

As shown in FIGS. 2 to 6, the reading device 1 includes, for example, a holding portion 20, a light source 30, a detector 40, a driving portion 50, a pair of guide portions 60, an erasing light source 70, a control portion 80, and an interface portion 95. Prepare. These components are provided within the housing 2 .

<About the control unit>
The control unit 80 can integrally manage the operation of the reading device 1, and can be said to be a control circuit. The control unit 80 can control the display unit 3, the holding unit 20, the light source 30, the detector 40, the driving unit 50, the erasing light source 70, and the interface unit 95, for example. Further, the control unit 80 can perform processing according to user operations received by the operation unit 4 .

The control unit 80 is configured by, for example, a computer device including at least one processor and a storage unit. At least one processor included in the control unit 80 may include a CPU (Central Processing Unit), or may include a processor other than the CPU. In the control unit 80, at least one processor executes a program in a storage unit (also referred to as a storage circuit) to implement various functions described below.

In the control unit 80, at least one processor executes a program in the storage unit, thereby forming functional blocks such as an image processing unit 81, a display control unit 82, a drive control unit 83, a holding control unit 84, and a detection control unit 85. , a light emission control section 86 and an erasing control section 87 are formed.

The image processor 81 can, for example, perform image processing on an image signal, which will be described later and is output from the detector 40 . The display control section 82 can control the display of the display section 3 . The drive control section 83 can control the drive section 50 . The holding control section 84 can control the holding section 20 . A detection control unit 85 can control the detector 40 . The light emission controller 86 can control the light source 30 . The erasing controller 87 can control the erasing light source 70 .

A part of the functions of the control unit 80 or all the functions of the control unit 80 may be implemented by a hardware circuit that does not require software (in other words, programs) to implement the functions. For example, part of the functions of the image processing unit 81 or all the functions of the image processing unit 81 may be implemented by hardware circuits that do not require software to implement the functions. The image processing unit 81 may be an image processing circuit independent of other components. A part of the functions of the display control unit 82 or all the functions of the display control unit 82 may be implemented by hardware circuits that do not require software to implement the functions. The display control section 82 may be a display control circuit independent of other components. A part of the functions of the drive control unit 83 or all the functions of the drive control unit 83 may be implemented by a hardware circuit that does not require software to implement the functions. The drive control section 83 may be a drive control circuit independent of other components. A part of the functions of the hold control unit 84 or all the functions of the hold control unit 84 may be implemented by hardware circuits that do not require software to implement the functions. The hold control section 84 may be a display control circuit independent of other components. A part of the functions of the detection control unit 85 or all the functions of the detection control unit 85 may be implemented by hardware circuits that do not require software to implement the functions. The detection control section 85 may be a detection control circuit independent of other components. Further, part of the functions of the light emission control section 86 or all the functions of the light emission control section 86 may be implemented by hardware circuits that do not require software to implement the functions. The light emission control section 86 may be a light emission control circuit independent of other components. Also, part of the functions of the erasure control unit 87 or all the functions of the erasure control unit 87 may be implemented by hardware circuits that do not require software to implement the functions. The erase control section 88 may be an erase control circuit independent of other components.

<About the interface part>
The interface section 95 can communicate with a device outside the housing 2 (hereinafter also referred to as an external device), and can be called an interface circuit, a communication circuit, or a communication section. The external device may include a personal computer, a mobile phone such as a smart phone, or other computer device. Further, the external device may include a data recording medium (for example, flash memory) that is removable from the reading device 1 . The interface unit 95 can receive a signal from an external device and input the received signal to the control unit 80 . Also, the interface unit 95 can transmit a signal from the control unit 80 to an external device. For example, the interface unit 95 can transmit an image signal image-processed by the image processing unit 81 of the control unit 80 to an external device. The interface unit 95 may perform wired communication with an external device, or may perform wireless communication. Communication between the interface unit 95 and the exterior device may conform to Ethernet, USB (Universal Serial Bus), WiFi, or other standards. You may

<Regarding the holding part>
The holding part 20 holds the imaging plate 10 inserted from the insertion opening 2 a of the housing 2 . The holding portion 20 includes, for example, a support plate 21 that supports the imaging plate 10 and a fixing portion 22 that fixes the position of the imaging plate 10 supported by the support plate 21 .

The support plate 21 includes a main surface 21a (also referred to as a support surface 21a) that supports the back surface of the imaging plate 10, and a main surface 21b (also referred to as a back surface 21b) opposite to the main surface 21a. The fixed part 22 has, for example, a plurality of fixed parts 22a that are close to the periphery of the imaging plate 10 . The fixing part 22 can also be said to be a fixing member. The plurality of fixed portions 22a approach the peripheral portion of the imaging plate 10 so as to surround the peripheral portion. Thereby, the position (that is, relative position) and posture (that is, relative posture) of imaging plate 10 with respect to support plate 21 are fixed. In this example, for example, two fixing portions 22a approach each of the long sides of the imaging plate 10, and one fixing portion 22a approaches each of both short sides of the imaging plate 10. FIG.

Each fixed portion 22a is controlled by the holding control unit 84 between an approach position approaching the imaging plate 10 supported by the support plate 21 and a separation position separating from the imaging plate 10 supported by the support plate 21. It is possible to move. The imaging plate 10 is inserted into the housing 2 through the insertion port 2a and supported by the support plate 21 with the fixing portions 22a positioned at the separated positions. Thereafter, the position and posture of the imaging plate 10 are fixed by the fixing portions 22 by moving the fixing portions 22a from the separated positions to the approached positions. Each fixed portion 22a is in contact with, for example, the peripheral portion of the imaging plate 10 when it is in the approached position.

Note that at least one of the plurality of fixed portions 22a does not have to come into contact with the peripheral portion of the imaging plate 10 when it exists at the approach position. Also, the configuration of the fixing portion 22 is not limited to the above. Also, the configuration of the holding portion 20 is not limited to the above.

<Regarding the driving part and the pair of guide parts>
Drive unit 50 can move holding unit 20 along predetermined direction DR<b>10 under the control of drive control unit 83 . Thereby, the imaging plate 10 held by the holding portion 20 can also be moved along the predetermined direction DR10. It can also be said that the drive unit 50 can move the imaging plate 10 along the predetermined direction DR10 through the holding unit 20 .

The pair of guide portions 60 extend along the predetermined direction DR10 with the holding portion 20 sandwiched therebetween. A groove extending along the predetermined direction DR10 is formed inside each guide portion 60 . A pair of side edges of the support plate 21 facing each other are fitted into grooves inside the pair of guide portions 60 . Thereby, the pair of guide portions 60 can guide the movement of the holding portion 20 along the predetermined direction DR10. Note that the configuration of the guide portion 60 is not limited to this.

The drive unit 50 is configured by, for example, a ball screw mechanism having a motor 51 , a screw shaft portion 52 and a nut portion 53 . The motor 51 is controlled by the drive control section 83 . The screw shaft portion 52 is a rod-shaped member with a thread groove formed around it. The screw shaft portion 52 extends along the predetermined direction DR<b>10 and is rotated by the motor 51 . The nut portion 53 is fixed to the holding portion 20 . The nut portion 53 is fixed to the back surface 21b of the support plate 21 of the holding portion 20, for example. The screw shaft portion 52 is screwed onto the nut portion 53 . As the motor 51 rotates forward or backward, the screw shaft portion 52 rotates forward or backward. Holding portion 20 moves to one side along predetermined direction DR10 in response to rotation of screw shaft portion 52 in the forward direction. At this time, the pair of guide portions 60 guide the movement of the holding portion 20 to one side. On the other hand, the holding portion 20 moves to the other side along the predetermined direction DR10 according to the rotation of the screw shaft portion 52 in the reverse direction. At this time, the pair of guide portions 60 guide the movement of the holding portion 20 to the other side. The configuration of the drive unit 50 is not limited to this.

The driving unit 50 can move the holding unit 20 holding the imaging plate 10 to a reading start position where reading of the radiation image from the imaging plate 10 is started. Further, when the reading of the radiographic image from the imaging plate 10 is completed, the drive unit 50 can move the holding unit 20 holding the imaging plate 10 to the erasing position where the radiographic image of the imaging plate 10 is erased. . 2 and 3 show how the radiation image is read from the imaging plate 10. FIG. FIGS. 4 and 5 show how the radiation image is erased from the imaging plate 10. FIG.

<About the light source and detector>
In this example, as shown in FIG. 6, the radiation image is read from the imaging plate 10 by the light source 30, the light emission controller 86 controlling it, the detector 40, and the detection controller 85 controlling it. An optical measuring device 90 is configured. The light source 30, the detector 40, the detection control section 85, and the light emission control section 86, which constitute the light measuring device 90, may be housed in one case and unitized, or may not be housed in one case. good.

The light source 30 can irradiate the imaging plate 10 held by the holding section 20 with excitation light L<b>1 for exciting the radiation image forming layer 11 . Light source 30 emits excitation light L<b>1 toward support surface 21 a of holding portion 20 . The light source 30 can scan the imaging plate 10 with the excitation light L1 in one direction (also referred to as the main scanning direction DRm). In this embodiment, the main scanning direction DRm is a direction perpendicular to the predetermined direction DR10. That is, the main scanning direction DRm is a direction perpendicular to the moving direction of the holding section 20 .

The excitation light L1 is, for example, visible laser light. The excitation light L1 may be, for example, red laser light or other color laser light. When the radiation image forming layer 11 is irradiated with the excitation light L1, the radiation image forming layer 11 emits light according to the distribution of the energy accumulated in the radiation image forming layer 11, and the radiation image forming layer 11 emits light L2. be done. The emitted light L2 is also called photostimulated light, and is blue visible light, for example. The detector 40 detects the emitted light L2 from the imaging plate 10 and outputs an electrical signal corresponding to the intensity of the detected emitted light L2.

The light source 30 has, for example, a laser generator that generates and outputs the excitation light L1 and a scanner that scans the imaging plate 10 with the excitation light L1 in the main scanning direction DRm. The laser generator is, for example, a semiconductor laser and is controlled by the light emission controller 86 . The laser generator may be a laser diode or another semiconductor laser. The scanning unit is, for example, a MEMS (Micro Electro Mechanical Systems) mirror that reflects the excitation light L1 from the laser generating unit toward the radiation image forming layer 11 of the imaging plate 10 . The MEMS mirror changes the reflection angle of the excitation light L1 under the control of the light emission control unit 86 so that the irradiation point of the excitation light L1 on the radiation image forming layer 11 moves in the main scanning direction DRm.

The detector 40 includes an optical filter 42 into which the emitted light L2 (see FIG. 3) from the imaging plate 10 is incident, and a sensor 41 that detects the emitted light L2 emitted from the optical filter 42 . The sensor 41 is controlled by the detection control section 85 . The optical filter 42 is arranged so as to face the detection surface of the emitted light L2 in the sensor 41 . The transmittance (also referred to as emitted light transmittance) of the optical filter 42 for the emitted light L2 is extremely high. Therefore, the optical filter 42 sufficiently transmits the emitted light L2 from the imaging plate 10 and emits it to the sensor 41 . On the other hand, the transmittance of the optical filter 42 for the excitation light L1 (also referred to as the excitation light transmittance) is lower than the emitted light transmittance. For example, the excitation light transmittance is about 10% of the emission light transmittance. Therefore, the optical filter 42 attenuates the reflected light of the excitation light L<b>1 from the imaging plate 10 toward the sensor 41 . In this disclosure, reflected light includes scattered light. Hereinafter, simply speaking of reflected light means the reflected light of the excitation light L1.

The sensor 41 can detect the emitted light L2 that has passed through the optical filter 42 and output an electrical signal corresponding to the intensity of the detected emitted light L2. The sensor 41 may be composed of, for example, a plurality of photodiodes or a photomultiplier tube.

When the reader 1 performs a process of reading a radiation image from the imaging plate 10 (also referred to as a reading process), the holding unit 20 holding the imaging plate 10 is conveyed to the reading start position by the driving unit 50 . Then, the light measuring device 90 starts the reading process. In the reading process, the light source 30 repeatedly performs a process of scanning the imaging plate 10 with the excitation light L1 in the main scanning direction DRm (also referred to as main scanning direction scanning) under the control of the light emission control unit 86 . On the other hand, in the reading process, the drive unit 50 moves the holding unit 20 holding the imaging plate 10 in one direction DRs (also called sub-scanning direction DRs) along the predetermined direction DR10. The sub-scanning direction DRs is a direction perpendicular to the main scanning direction DRm. While the holding unit 20 is moving in the sub-scanning direction DRs, scanning in the main scanning direction is repeatedly performed, whereby the radiation image forming layer 11 of the imaging plate 10 is raster-scanned with the excitation light L1. Thus, in the reading process, the entire area of the radiation image forming layer 11 is sequentially irradiated with the excitation light L1, and the entire area of the radiation image forming layer 11 is scanned with the excitation light L1. While the radiation image forming layer 11 is raster-scanned with the excitation light L1, the sensor 41 of the detector 40 detects the emitted light L2 sequentially emitted from the radiation image forming layer 11 according to the raster scanning, thereby forming a radiation image. A radiation image is read from the forming layer 11 . The sensor 41 outputs an image signal representing the read radiographic image (in other words, the detected radiographic image) to the detection control unit 85 as a detection result of the emitted light L2 during raster scanning of the excitation light L1. This image signal includes luminance values (in other words, pixel values) of a plurality of pixels representing the read radiation image. The sensor 41 outputs, for example, a grayscale image signal. Hereinafter, the radiographic image read by the detector 40 may be called a detected radiographic image.

Here, scanning in the present application will be described. In raster scanning, a two-dimensional object to be scanned is one-dimensionally scanned (scanned) at points to obtain lines (scan lines). It may refer to a method of obtaining a two-dimensional surface image by repeating one-dimensional scanning. If the purpose of obtaining an image of a two-dimensional surface can be achieved, the one-dimensional scanning does not have to be a straight line scanning and the shifting direction does not have to be perpendicular. Also, the unit scanning does not necessarily have to be in the same direction, and for example, may be repeated in opposite directions. In the present application, each of the scans gathered to form a two-dimensional surface image is defined as a unit scan, like the one-dimensional scan of the raster scan, and the scanning direction of the unit scan is defined as the main scanning direction. A direction that intersects the unit scan, such as the perpendicular direction, is defined as the unit scan cross direction, and repeating two-dimensional scanning while shifting the unit scan in the unit scan direction is referred to as unit scan repetitive scan. A scan in which the unit scan is moved in the direction crossing the unit scan in order to repeat the unit scan is referred to as a sub-scan, and a unit scan performed in the direction crossing the sub-scan is referred to as a main scan. The main scanning direction can be said to be the scanning direction of main scanning, and the sub-scanning direction can be said to be the scanning direction of sub-scanning. Scanning employed in the configuration of the present application may be repetitive unit-scanning, but in the description of the embodiments, scanning by raster scanning will be described as a representative of repetitive unit-scanning.

In this example, when the imaging plate 10 is properly held by the holding unit 20, the lateral direction of the imaging plate 10 is parallel to the main scanning direction DRm as shown in FIGS. The longitudinal direction of the plate 10 is parallel to the sub-scanning direction DRs. Here, the posture of the imaging plate 10 in a state in which the imaging plate 10 is appropriately held by the holding unit 20 is called a reference posture. , and the longitudinal direction of the imaging plate 10 is parallel to the sub-scanning direction DRs. Note that the reference posture is not limited to this.

The imaging plate 10 is basically held by the holding section 20 in a reference posture. However, if the holding section 20 does not properly hold the imaging plate 10 due to a defect of the fixing section 22 or the like, the imaging plate 10 may be held by the holding section 20 in a state inclined from the reference posture.

In this example, the sensor 41, for example, outputs a larger luminance value as the intensity of the detected light increases. In the radiation image forming layer 11 of the imaging plate 10, the intensity of the emitted light L2 from that portion increases as the irradiation intensity of the radiation increases and the accumulated energy increases. Therefore, the luminance value output by the sensor 41 for an image based on the detection of the emitted light L2 from the portion of the radiation image forming layer 11 having a large accumulated energy is increased.

For example, consider the case where a radiation image of teeth is recorded on the radiation image forming layer 11 . In this case, the intensity of the emitted light L2 from the portion where the radiation image of the tooth is recorded in the radiation image forming layer 11, that is, the portion irradiated with the radiation that has passed through the tooth is relatively small. Therefore, the luminance value from the sensor 41 for the portion of the detected radiation image where the tooth is reflected is relatively small. On the other hand, the intensity of the emitted light L2 from the portion directly irradiated with the radiation (also referred to as the directly irradiated portion) in the radiation image forming layer 11 is relatively high. Therefore, among the detected radiation images, the brightness value output from the sensor 41 for the image corresponding to the directly irradiated portion of the radiation image forming layer 11 is relatively large.

In this example, the optical filter 42 attenuates the excitation light L1, but transmits the excitation light L1 to some extent. Therefore, the sensor 41 detects not only the emitted light L2 emitted by the imaging plate 10 but also the reflected light of the excitation light L1 on the imaging plate 10 to some extent. Therefore, the luminance value of the detected radiation image output from the sensor 41 includes a luminance value corresponding to the detected intensity of the emitted light L2 (also referred to as a luminance value corresponding to the emitted light) and a luminance corresponding to the detected reflected light. values (also referred to as luminance values corresponding to reflected light). The luminance value corresponding to emitted light is, for example, a value that is ten times or more than the luminance value corresponding to reflected light. Therefore, the detected radiation image based on the image signal output from the detector 40 is not greatly affected by the reflected light, and appropriately represents the radiation image recorded on the imaging plate 10 .

In this example, the radiation image forming layer 11 of the imaging plate 10 may partially have an unexposed portion where the energy corresponding to the irradiation of the radiation is not accumulated. For example, when the imaging plate 10 is irradiated with radiation through an object to be photographed, the position of the light source that emits the radiation may shift, causing the portion of the radiation image forming layer 11 to be irradiated with the radiation to be exposed to the radiation. is not irradiated, and partially unexposed areas may occur. This partial unexposed portion is sometimes called a cone cut. In addition, in the radiation image forming layer 11, the radiation image may unintentionally disappear from the radiation-irradiated portions, resulting in partially unexposed portions. For example, the imaging plate 10 for recording a radiographic image is usually stored with a cover so that it is not exposed to ambient light. However, if the imaging plate 10 is not properly covered with a cover, ambient light will irradiate a portion of the radiation image forming layer 11 during storage of the imaging plate 10, causing the radiation recorded in that portion to be exposed to radiation. Images may be erased unintentionally. In this case also, the radiation image forming layer 11 will partially have unexposed areas.

Even if the unexposed portion of the imaging plate 10 is irradiated with the excitation light L1, the unexposed portion does not emit the emission light L2. Therefore, when the excitation light L1 is applied to the unexposed portion, the detector 40 detects the reflected light of the excitation light L1 at the unexposed portion without detecting the emitted light L2. Therefore, the image signal output by the detector 40 includes the luminance values of a plurality of pixels representing the reflected light image of the unexposed portion, that is, the reflected light image based on the detection of the reflected light of the excitation light L1 from the unexposed portion. may be included. The entire image based on the image signal output by the detector 40 as the detection result of the emitted light L2 and the reflected light includes not only the detected radiation image based on the detection of the emitted light L2 but also the reflected light image of the unexposed portion (unexposed image). Also called an area image) may also be included. The luminance value of the detected radiation image output by the detector 40 is, for example, ten times or more the luminance value of the unexposed area image output by the detector 40 .

In this example, in the reading process, not only the imaging plate 10 but also the portion of the holding unit 20 outside the imaging plate 10 is irradiated with the excitation light L1. Here, an object irradiated with the excitation light L1 in the reader 1 is called an irradiation object 1200 . In this example, the object to be irradiated 1200 is composed of the holding section 20 and the imaging plate 10 held by the holding section 20 . A main surface 1200a of the irradiation object 1200 on the support surface 21a side is called a support-side main surface 1200a. In this example, the main surface 1200a on the support side includes the surface of the radiation image forming layer 11 of the imaging plate 10, the surface of the fixed portion 22 of the holding portion 20, and the supporting surface 21a of the supporting plate 21 of the holding portion 20. The area not covered by the plate 10 and the fixed part 22 is included. A region R100 where the imaging plate 10 exists on the support-side main surface 1200a is called an IP existing region R100. Note that the main surface of the irradiation object 1200 on the side opposite to the support-side main surface 1200 a coincides with the back surface 21 b of the support plate 21 .

In this example, the irradiation range (also referred to as excitation light irradiation range) R120 of the excitation light L1 with respect to the support-side main surface 1200a in the reading process is a range that includes the IP existence region R100 and is larger than it. The excitation light irradiation range R120 can also be said to be the scanning range of the excitation light L1 in the reading process. Further, the detection range R110 on the support-side main surface 1200a of the detector 40 in the reading process is also a range that includes the IP existence region R100 and is larger than it.

FIG. 7 is a schematic diagram showing an example of an excitation light irradiation range R120, a detection range R110, and an IP existence region R100. The illustration of the imaging plate 10 is omitted in FIG. 7 and FIGS. 8 and 9 described later. As shown in FIG. 7, each of the excitation light irradiation range R120 and the detection range R110 includes the IP existence region R100 and is larger than the IP existence region R100. For example, the excitation light irradiation range R120 and the detection range R110 have the same size and are located at the same position. In addition, in FIG. 7, for convenience of explanation, the excitation light irradiation range R120 is shown slightly larger than the detection range R110.

In the reading process, the holding unit 20 holding the imaging plate 10 moves in the sub-scanning direction DRs while the light source 30 repeatedly scans in the main scanning direction. Scanned. Then, the sensor 41 sequentially outputs luminance values according to the irradiation position of the excitation light L1 in the detection range R110 according to the raster scan of the excitation light L1.

Here, on the support-side main surface 1200a, a region outside the IP existence region R100 and inside the excitation light irradiation range R120 and the detection range R110 is called an IP outside region R130. In this example, since the excitation light irradiation range R120 and the detection range R110 include the IP existence region R100 and are larger than the IP existence region R100, the sensor 41 detects the excitation light from the IP outer region R130. The reflected light of L1 is detected. The IP outer region R130 includes, for example, at least part of the surface of the fixing part 22 and at least part of the area of the support surface 21a of the support plate 21 that is not covered with the imaging plate 10 and the fixing part 22. . IP outer region R130 is included in the surface of holding portion 20, specifically, the main surface of holding portion 20 on the imaging plate 10 side.

Even if the IP outer region R130 is irradiated with the excitation light L1, the emission light L2 is not emitted from the IP outer region R130. Therefore, when the IP outer region R130 is irradiated with the excitation light L1, the detector 40 detects the reflected light of the excitation light L1 from the IP outer region R130 without detecting the emitted light L2. Therefore, in the reading process, the image signal output by the detector 40 as the detection result of the emitted light L2 and the reflected light includes the reflected light image of the IP outer region R130, that is, the reflected light of the excitation light L1 from the IP outer region R130. Intensity values of a plurality of pixels representing a reflected light image based on the detection of . In this example, the overall image based on the image signal output by the detector 40 (also referred to as an acquired overall image) includes not only the detected radiation image but also the reflected light image of the IP outer region R130. If the imaging plate 10 includes an unexposed portion, the acquired overall image includes the detected radiation image, the unexposed area image, and the reflected light image of the IP outer area R130. Hereinafter, the reflected light image of the IP outer region R130 may be referred to as an IP outer region image.

In this example, the IP outer region R130 is subjected to a process that makes it difficult for the excitation light L1 to be reflected. For example, the IP outer region R130 is subjected to black alumite treatment. This makes it more difficult for the detector 40 to detect the reflected light of the excitation light L1 on the IP outer region R130 than the reflected light of the excitation light L1 on the unexposed portion of the imaging plate 10 . In this example, due to the black alumite treatment, the IP outer region R130 hardly reflects the excitation light L1. The luminance value of the unexposed area image output by the detector 40 is, for example, three times or more the luminance value of the IP outer area image output by the detector 40 . Note that the black alumite treatment may also be performed on a region other than the IP outer region R130 on the surface of the holding portion 20 . For example, the black alumite treatment may be performed on the entire surface area of the holding portion 20 .

The relationship between the excitation light irradiation range R120, the detection range R110, and the IP existence region R100 is not limited to the above example. 8 and 9 are schematic diagrams showing other examples of the excitation light irradiation range R120, the detection range R110, and the IP existence region R100. In the example of FIG. 8, the excitation light irradiation range R120 includes the detection range R110 and the IP existence region R100, but is larger than the detection range R110 and the IP existence region R100. In the example of FIG. 9, the detection range R110 includes the excitation light irradiation range R120 and the IP existence region R100, but is larger than the excitation light irradiation range R120 and the IP existence region R100.

In the example of FIG. 9, the detection range R110 includes a region other than the excitation light irradiation range R120 (also referred to as a non-irradiation range region) on the support-side main surface 1200a. Therefore, although the image signal output by the detector 40 also includes the brightness value corresponding to the area outside the irradiation range, the brightness value is zero. In this case, the detector 40 may output an image signal that does not include the luminance value corresponding to the non-irradiation area.

<About light source for erasing>
In this example, as shown in FIG. 6, an erasing light source 70 and an erasing control part 87 for controlling the erasing light source 70 constitute an erasing part 91 that performs an erasing process for erasing a radiation image from the imaging plate 10 . . The erasing light source 70 and the erasing control section 87 that constitute the erasing section 91 may be housed in one case to form a unit, or may not be housed in one case. The erasing light source 70 can irradiate the imaging plate 10 with erasing light L3 for erasing the radiation image from the imaging plate 10 . The erasing light L3 is, for example, visible light. The erasing light L3 may be white light, red visible light, or other colors of visible light. The erasing light source 70 may be an LED (Light Emission Diode), a halogen lamp, or another light source.

As shown in FIGS. 4 and 5, the erasing light source 70 can irradiate the entire area of the radiation image forming layer 11 of the imaging plate 10 with the erasing light L3, for example, in one irradiation. In the erasing process, the radiation image is erased from the radiation image forming layer 11 by irradiating the radiation image forming layer 11 with the erasing light L3.

When the reading process by the optical measuring device 90 is completed, the driving section 50 moves the holding section 20 holding the imaging plate 10 to the erasing position. When the holding section 20 moves to the erasing position, the erasing section 91 performs erasing processing. In the erasing process, the erasing light source 70 irradiates the entire region of the radiation image forming layer 11 of the imaging plate 10 with the erasing light L3 under the control of the erasing controller 87 . As a result, the radiation image is erased from the imaging plate 10 .

When the radiation image is erased from the imaging plate 10, the driving section 50 moves the holding section 20 to the discharge position. When the holding portion 20 moves to the ejection position, each fixed portion 22a of the holding portion 20 moves from the approach position to the separation position. After that, the imaging plate 10 from which the radiation image has been erased is ejected to the outlet 2b. Hereinafter, the erased imaging plate 10 means the imaging plate 10 from which the radiation image has been erased.

<About the image processing unit>
An image processing unit 81 of the control unit 80 receives image signals output from the sensor 41 through the detection control unit 85 . The image processing unit 81 associates pixel position information with each of a plurality of luminance values included in the image signal from the sensor 41 . The pixel position information associated with a certain luminance value is information indicating the position (also referred to as pixel position) of a pixel having the certain luminance value in the acquired overall image.

Here, in the reading process, the driving unit 50 moves the holding unit 20 in the sub-scanning direction DRs in accordance with the repetition of scanning in the main scanning direction. Specifically, the driving unit 50 moves the holding unit 20 in the sub-scanning direction DRs so that the entire area of the excitation light irradiation range R120 is irradiated with the excitation light L1 while the scanning in the main scanning direction is performed a predetermined number of times. Moving. Then, the sensor 41 sequentially outputs luminance values according to the irradiation position of the excitation light L1 in the detection range R110 according to the raster scan of the excitation light L1. In the reading process, since the reading device 1 operates as described above, the excitation light irradiation range R120, the detection range R110, the time required for one scan in the main scanning direction, the repetition period of the scan in the main scanning direction, and the reading If the number of scans in the main scanning direction in the process is known, it is possible to know the luminance value of the pixel at which position in the acquired overall image the luminance value output by the sensor 41 at a certain timing. The image processing unit 81 stores the excitation light irradiation range R120, the detection range R110, the time required for one scan in the main scanning direction, the repetition period of the scan in the main scanning direction, and the number of times the scan in the main scanning direction is executed in the reading process. , the pixel position information is associated with each of the plurality of luminance values included in the image signal from the sensor 41 . Note that the detection control unit 85 may associate pixel position information with each of a plurality of luminance values included in the image signal from the sensor 41 .

Also, the image processing unit 81 performs image processing on the image signal from the sensor 41 . The image processing unit 81 outputs, for example, an image signal after image processing and pixel position information associated with each luminance value included in the image signal to the display control unit 82 . The display control unit 82 displays, on the display unit 3, the obtained whole image including the detected radiographic image, based on the image signal after the image processing and the pixel position information associated with each luminance value of the image signal, for example. Let

The image processing performed by the image processing unit 81 may include brightness inversion processing. The brightness reversal process is a process of converting each brightness value of the image signal before the brightness reversal process so that the larger the brightness value, the smaller the brightness value. Here, the maximum value of the possible range of luminance values is called the maximum luminance value. For example, a value obtained by subtracting a certain luminance value included in the image signal before luminance inversion processing from the maximum luminance value becomes the certain luminance value after conversion. By performing luminance inversion processing on the image signal, the image signal after image processing differs from the image signal before image processing based on the detection of emitted light L2 from a portion of the imaging plate 10 where the accumulated energy is small. The luminance value of the radiation image increases, and the luminance value of the radiation image based on the detection of the emitted light L2 from the portion of the imaging plate 10 where the accumulated energy is large decreases. Further, in the image signal after image processing, the luminance value of the unexposed area image and the luminance value of the IP outer area image are larger than the luminance value of the detected radiographic image.

Note that the image processing performed by the image processing unit 81 may not include the luminance inversion processing, or may include processing other than the luminance inversion processing. Image processing may include, for example, offset correction and logarithmic conversion as processing other than luminance inversion processing.

10 and 11 are schematic diagrams showing an example of an acquired global image (also referred to as a pre-reversal global image) 100a based on the image signal before luminance reversal processing is performed. 12 and 13 are schematic diagrams showing an example of an acquired overall image (also referred to as an inverted overall image) 100b based on the image signal after luminance inversion processing has been performed. In FIGS. 10-13, the pre-inverted global image 100a and the post-inverted global image 100b are shown in grayscale. In FIGS. 10 to 13, the image appears brighter (in other words, whiter) as the luminance value of the image increases, and the image appears darker (in other words, blacker) as the luminance value of the image decreases. The same applies to later-described figures showing images obtained by the reading device 1. FIG.

FIG. 10 shows a pre-inversion whole image 100a including a radiation image (in other words, a detection radiation image) 101a based on detection of the emitted light L2 and an IP outer region image 102a. FIG. 11 shows a pre-reversal overall image 100a including a radiation image 101a, an IP outer area image 102a, and an unexposed area image 103a. FIG. 12 shows an inverted overall image 100b including a radiation image 101b and an IP outer region image 102b. FIG. 13 shows an inverted overall image 100b including a radiation image 101b, an IP outer area image 102b, and an unexposed area image 103b. In this example, since the detection range R110 of the sensor 41 is rectangular, the shape of the obtained whole image is rectangular as shown in FIGS.

When the display control unit 82 causes the display unit 3 to display the post-reversal overall image 100b based on the image signal after the image processing, the display control unit 82 displays the post-reversal overall image 100b in grayscale as shown in FIGS. 12 and 13, for example. Display in part 3. 12 and 13 can also be said to be diagrams showing display examples of the post-reversal overall image 100b. Further, when the display control unit 82 causes the display unit 3 to display the pre-inversion whole image 100a based on the image signal before the luminance inversion processing is performed, the display control unit 82, for example, inverts the image in a gray scale as shown in FIGS. The front whole image 100a is displayed on the display unit 3. FIG. 10 and 11 can also be said to be diagrams showing display examples of the pre-reversal whole image 100a.

<Example of reading device operation>
FIG. 14 is a diagram showing a flowchart showing an example of the operation of the reading device 1. As shown in FIG. When the imaging plate 10 inserted from the insertion opening 2a of the housing 2 is held by the holding portion 20 and the start button included in the operation portion 4 is operated, step s1 in FIG. 14 is executed. It can be said that the operation of the start button is an instruction to start the series of processes shown in FIG.

At step s1, the driving unit 50 moves the holding unit 20 to the reading start position under the control of the driving control unit 83. FIG. Next, in step s2, the optical measuring device 90 performs reading processing for reading a radiation image from the imaging plate 10. FIG. Next, in step s3, the driving section 50 moves the holding section 20 to the erasing position under the control of the driving control section 83. FIG. Next, in step s4, the erasing light source 70 irradiates the imaging plate 10 with the erasing light L3 under the control of the erasing control unit 87, thereby performing erasing processing in which the radiation image is erased from the imaging plate 10. FIG. Next, in step s5, the driving section 50 moves the holding section 20 to the ejection position under the control of the driving control section 83. As shown in FIG. Next, in step s6, the imaging plate 10 is ejected to the outlet 2b of the housing 2. FIG. Then, in step s7, the display unit 3 displays the obtained overall image under the control of the display control unit 82. FIG. In step s7, the display unit 3 displays the reversed whole image in grayscale as shown in FIGS. 12 and 13, for example. Note that step s7 may be executed at any time after step s2. For example, step s7 may be performed between steps s3 and s4.

<Identification of the tilt angle of the imaging plate>
The image processing unit 81 may perform, for example, an inclination angle specifying process of specifying an inclination angle (also referred to as an IP inclination angle) from the reference orientation of the imaging plate 10 . In the tilt angle identification process, the image processing unit 81 identifies the IP tilt angle, for example, based on the image signal output by the detector 40 . The image processing unit 81 functions as a specifying unit that specifies the IP tilt angle. A specific example of the tilt angle specifying process will be described below, but the tilt angle specifying process is not limited to the example below.

As described above, the reference posture in this example is the posture of the imaging plate 10 in which the lateral direction and longitudinal direction of the imaging plate 10 are parallel to the main scanning direction DRm and the sub-scanning direction DRs, respectively. When the imaging plate 10 held by the holding part 20 is not properly held by the holding part 20, the imaging plate 10 held by the holding part 20 is viewed from the front side, as shown in FIG. (also referred to as the longitudinal direction) is tilted with respect to the sub-scanning direction DRs, and the imaging plate 10 may be tilted with respect to the reference posture. In other words, the lateral direction (also referred to as the IP lateral direction) of imaging plate 10 may be tilted with respect to main scanning direction DRm, and imaging plate 10 may be tilted with respect to the reference posture. In FIG. 15, the imaging plate 10 in the reference posture is indicated by broken lines.

In this example, the IP tilt angle, that is, the tilt angle of the imaging plate 10 from the reference orientation matches the tilt angle of the IP longitudinal direction with respect to the sub-scanning direction DRs. In other words, the IP tilt angle matches the tilt angle of the IP lateral direction with respect to the main scanning direction DRm.

On the other hand, the longitudinal direction of the detection range R110 (see FIG. 7 and the like) of the sensor 41 corresponds to the longitudinal direction of the overall image acquired based on the image signal from the sensor 41 . In this example, since the longitudinal direction of the detection range R110 is parallel to the sub-scanning direction DRs, it can be said that the longitudinal direction of the obtained whole image corresponds to the sub-scanning direction DRs. Therefore, when the posture of the imaging plate 10 is the reference posture, the longitudinal direction of the acquired entire image and the longitudinal direction of the portion corresponding to the imaging plate 10 (also referred to as the IP corresponding portion) of the acquired entire image match each other. do. On the other hand, when the imaging plate 10 is tilted with respect to the reference posture, the longitudinal direction of the IP-corresponding portion of the acquired overall image is tilted with respect to the longitudinal direction of the acquired overall image. In other words, when the imaging plate 10 is tilted with respect to the reference posture, the widthwise direction of the portion corresponding to the IP included in the acquired overall image is tilted with respect to the widthwise direction of the acquired overall image.

FIG. 16 is a diagram showing an example of a pre-inversion whole image 100a obtained when the imaging plate 10 is tilted with respect to the reference posture. In the example of FIG. 16, the longitudinal direction of the IP-corresponding portion 105a included in the pre-reversal whole image 100a is inclined with respect to the longitudinal direction of the pre-reversal whole image 100a. The tilt angle of the IP corresponding portion 105a in the longitudinal direction with respect to the longitudinal direction of the whole image 100a before reversal matches the IP tilt angle.

Thus, in this example, the tilt angle in the longitudinal direction of the portion corresponding to the IP with respect to the longitudinal direction of the obtained entire image matches the IP tilt angle. Therefore, based on the image signal from the sensor 41, the image processing unit 81 obtains the inclination angle of the portion corresponding to the IP in the longitudinal direction with respect to the longitudinal direction of the obtained entire image. Then, the image processing unit 81 sets the obtained tilt angle as the IP tilt angle. The operation of this image processing unit 81 will be described in detail below.

In the tilt angle specifying process, the image processing unit 81 binarizes the pre-inversion whole image based on the image signal before the luminance inversion process (also referred to as the image signal before inversion) to generate a binarized image. The image processing unit 81 first compares each luminance value of the pre-inversion whole image, which is included in the pre-inversion image signal, with a preset threshold value. Then, the image processing unit 81 replaces luminance values equal to or greater than the threshold value with "1" and substitutes luminance values less than the threshold value with "0" for each luminance value of the pre-reversal whole image. As a result, the whole image before reversal is binarized to obtain a binarized image.

The threshold value used in binarization is, for example, greater than the luminance value of the IP outer area image included in the image signal before inversion and more than the luminance value of the unexposed area image included in the image signal before inversion. is also set to a small value. For example, consider a case where the brightness value of the IP outer area image included in the image signal before inversion is 1000 and the brightness value of the unexposed area image included in the image signal before inversion is 3000. FIG. In this case, the threshold is set to 2000, for example. The threshold value is set based on, for example, an image signal before reversal obtained by the reading device 1 before actual operation, and is stored in advance in the image processing section 81 of the reading device 1 . Since the luminance value of the detected radiation image contained in the image signal before inversion is greater than the luminance value of the unexposed area image contained in the image signal before inversion (see FIG. 11), the threshold value is It is smaller than the luminance value of the detected radiation image included in the image signal before inversion.

By setting the threshold values as described above, each luminance value of the portion corresponding to the IP outer region becomes "0" in the binarized image. Further, regardless of whether or not the imaging plate 10 includes an unexposed portion, each luminance value of the portion corresponding to the imaging plate 10 is "1" in the binarized image.

FIG. 17 is a schematic diagram showing an example of a binarized image 500. As shown in FIG. FIG. 17 shows a binarized image 500 obtained by binarizing the pre-inversion whole image 100a shown in FIG. In FIG. 17, in a binarized image 500, an area 501 with a luminance value of "1" (also called a high luminance area) is shown in white, and an area 502 with a luminance value of "0" (also called a low luminance area) is shown in white. Shown in black. As can be understood from FIG. 17, in the binarized image 500, the high brightness area 501 corresponds to the imaging plate 10, and the low brightness area 502 corresponds to the IP outer area. The outer shape of the high-brightness region 501 has a shape corresponding to the outer shape of the imaging plate 10 .

Here, a high brightness area 501 included in the binarized image 500 corresponds to the IP equivalent portion 105a included in the pre-inversion whole image 100a. In the tilt angle specifying process, the image processing unit 81 performs principal component analysis on the positions of a plurality of pixels forming the high-brightness region 501 included in the generated binarized image 500 as data to be analyzed. Find the first principal component axis of

In the principal component analysis, the image processing unit 81 obtains the center of gravity 501a (see FIG. 17) of the high brightness area 501 included in the binarized image 500. FIG. Then, the image processing unit 81 sets an XY coordinate system with the center of gravity 501a as the origin for the binarized image 500, as shown in FIG. At this time, the X-axis is parallel to the longitudinal direction of the pre-reversal overall image 100a, and the Y-axis is parallel to the lateral direction of the pre-reversal overall image 100a. As will be described later, the image processing unit 81 rotates the XY coordinate system around the center of gravity 501a. In this example, the clockwise rotation angle of the XY coordinate system is positive, and the counterclockwise rotation angle of the XY coordinate system is negative. The orientation of the XY coordinate system in which the X axis is parallel to the longitudinal direction of the pre-reversal overall image 100a and the Y axis is parallel to the lateral direction of the pre-reversal overall image 100a is called an initial posture.

When the image processing unit 81 sets the XY coordinate system of the initial posture for the binarized image 500, for each of the plurality of pixels forming the high-brightness region 501, a vertical line drawn from the pixel position 510 to the Y axis Find the length L of Next, the image processing unit 81 obtains the variance of the plurality of lengths L obtained for the plurality of pixels forming the high-brightness region 501 . This variance is called the variance in the initial posture.

The image processing unit 81 rotates the XY coordinate system about the center of gravity 501a clockwise 520R from the initial posture by 0.1 degrees, for example, and similarly rotates the XY coordinate system by 0.1 degrees. A clockwise process is performed to find the variance of L. In the clockwise processing, the image processing unit 81 finally rotates the XY coordinate system clockwise 520R, for example, by 90 degrees. Further, the image processing unit 81 rotates the XY coordinate system about the center of gravity 501a from the initial posture counterclockwise 520L, for example, by 0.1 degrees each time the XY coordinate system is rotated by 0.1 degrees. Perform counterclockwise processing to find the variance of length L of . In the counterclockwise process, the image processing unit 81 finally rotates the XY coordinate system counterclockwise 520L by, for example, 90 degrees.

After executing the clockwise and counterclockwise processing, the image processing unit 81 specifies the minimum value among the plurality of variances obtained in the clockwise and counterclockwise processing and the variance in the initial posture. Then, the image processing unit 81 sets the Y axis of the XY coordinate system when the specified minimum value is obtained as the first principal component axis. The first principal component axis can be said to be the axis that minimizes the variance of the lengths of perpendicular lines drawn from the positions of the plurality of pixels forming the high-brightness region 501 . Hereinafter, an axis that is perpendicular to the first principal component axis and that passes through the center of gravity 501a may be referred to as a second principal component axis. Also, the XY coordinate system in which the minimum value among the multiple variances obtained in the clockwise and counterclockwise processing and the variance in the initial posture is obtained is sometimes called the XY coordinate system of the minimum variance posture. .

FIG. 18 is a schematic diagram showing the first principal component axis 551 obtained from the binarized image 500 shown in FIG. In FIG. 18, the Y-axis of the XY coordinate system in the initial posture is indicated by a dashed line. As shown in FIG. 18 , the first principal component axis 551 coincides with the longitudinal direction of the high brightness region 501 . After obtaining the first principal component axis 551, the image processing unit 81 obtains the rotation angle α Ask for Then, the image processing unit 81 sets the obtained rotation angle α to the longitudinal direction inclination angle α of the portion corresponding to the IP with respect to the longitudinal direction of the obtained entire image. The Y axis of the XY coordinate system of the initial posture corresponds to the longitudinal direction of the acquired whole image, and the first principal component axis 551 (in other words, the Y axis of the XY coordinate system of the minimum variance posture) corresponds to the IP included in the acquired whole image. Corresponds to the longitudinal direction of the part. Therefore, it can be said that the rotation angle α is the inclination angle of the portion corresponding to the IP in the longitudinal direction with respect to the longitudinal direction of the acquired entire image. When the XY coordinate system of the minimum variance attitude is obtained in clockwise processing, the rotation angle α indicates a positive value, and when the XY coordinate system of the minimum variance attitude is obtained in counterclockwise processing, the rotation angle α is Indicates a negative value. Then, when the XY coordinate system of the minimum variance attitude matches the XY coordinate system of the initial attitude, the rotation angle α becomes zero.

When the image processing unit 81 obtains the tilt angle α in the longitudinal direction of the portion corresponding to the IP with respect to the longitudinal direction of the obtained whole image from the binarized image 500 of the obtained whole image as described above, the image processing unit 81 converts the obtained tilt angle α to the IP Let the tilt angle be α. When the imaging plate 10 is viewed from the front side, the imaging plate 10 tilts clockwise with respect to the reference posture when the IP tilt angle α is positive, and the imaging plate 10 tilts clockwise when the IP tilt angle α is negative. is inclined counterclockwise with respect to the reference posture. Hereinafter, with respect to the tilt of the imaging plate 10, the term "clockwise rotation" means the clockwise rotation when the imaging plate 10 is viewed from its front side, and the term "counterclockwise rotation" simply refers to the clockwise rotation when the imaging plate 10 is viewed from its front side. means counterclockwise rotation when

The tilt angle specifying process as described above may be executed during the series of processes shown in FIG. 14 described above, or may be executed at a timing different from the process shown in FIG. Also, the IP tilt angle obtained by the image processing unit 81 may be displayed on the display unit 3 . At this time, the display unit 3 may display the IP tilt angle at the same time as the obtained overall image in step s7 described above, or may display the obtained overall image when not displaying the obtained overall image.

As described above, in this example, the image processing unit 81 identifies the IP tilt angle based on the image signal as the detection result of the emitted light L2 and the reflected light from the imaging plate 10. Therefore, the IP tilt angle is can be properly identified.

For example, consider the case where the sensor 41 cannot detect reflected light and the imaging plate 10 includes an unexposed portion. In this case, the brightness values of the unexposed area image and the IP outer area image included in the pre-reversal whole image based on the image signal from the sensor 41 are zero. Therefore, in the binarized image 500 obtained by binarizing the whole image before reversal, the luminance values of the portions corresponding to the unexposed area image and the IP outside area image are all "0", and the unexposed area image and the IP outside area image are all "0". All the portions corresponding to the area image become the low luminance area 502 . Therefore, when the imaging plate 10 includes an unexposed portion, the high-brightness region 501 of the binarized image 500 does not include the portion corresponding to the unexposed portion, and the high-brightness region 501 is the whole image before inversion. It no longer corresponds to the included IP equivalent part. In other words, if the imaging plate 10 includes an unexposed portion, the outer shape of the high-brightness region 501 does not conform to the outer shape of the imaging plate 10 . Therefore, when the principal component analysis is performed on the high luminance region 501, the image processing unit 81 cannot obtain the first principal component axis corresponding to the longitudinal direction of the imaging plate 10. There is a possibility that the tilt angle in the longitudinal direction of the IP-corresponding portion cannot be obtained appropriately.

On the other hand, in this example, the sensor 41 can detect the reflected light to some extent, and the image processing unit 81 detects the emitted light L2 from the imaging plate 10 and the image signal as the detection result of the reflected light. A binarized image 500 is generated by binarizing the entire image. Therefore, in the binarized image 500, even if the imaging plate 10 includes an unexposed portion, as shown in FIGS. It comes to correspond to the IP equivalent part. That is, the outer shape of the high-brightness region 501 has a shape corresponding to the outer shape of the imaging plate 10 . As a result, the image processing unit 81 can obtain the first principal component axis corresponding to the longitudinal direction of the imaging plate 10 when principal component analysis is performed on the high luminance region 501, and the IP The inclination angle of the corresponding portion in the longitudinal direction can be obtained appropriately. Therefore, the image processing unit 81 can appropriately specify the IP tilt angle.

<Specifying the size of the imaging plate>
The image processing unit 81 may perform, for example, size identification processing for identifying the size (also referred to as IP size) of the imaging plate 10 . In the size identification process, the image processing unit 81 identifies the IP size, for example, based on the image signal output by the detector 40 . The image processing unit 81 functions as a specifying unit that specifies the IP size. A specific example of the size identification process will be described below, but the size identification process is not limited to the following example.

For example, the image processing unit 81 binarizes the pre-inversion whole image based on the pre-inversion image signal to generate the binarized image 500 in the same manner as described above. The image processing unit 81 then identifies the IP size based on the generated binarized image 500 . For example, the image processing unit 81 numerically specifies the size of the imaging plate 10 in the longitudinal direction (also referred to as the longitudinal size) and the size of the imaging plate 10 in the lateral direction (also referred to as the lateral size).

When specifying the IP size, the image processing unit 81 performs principal component analysis on the positions of the plurality of pixels forming the high-brightness region 501 included in the binarized image 500 as data to be analyzed in the same manner as described above. , the first principal component axis 551 for the data to be analyzed is determined. Then, the image processing unit 81 obtains a second principal component axis 552 that is perpendicular to the first principal component axis 551 and passes through the center of gravity 501a.

FIG. 19 is a schematic diagram showing an example of the first principal component axis 551 and the second principal component axis 552. FIG. FIG. 19 shows a binarized image 500 obtained by binarizing the whole image 100a before reversal shown in FIG. and a second principal component axis 552 are shown. The first principal component axis 551 is parallel to the longitudinal direction of the high luminance region 501 corresponding to the imaging plate 10 . Also, the second principal component axis 552 is parallel to the short direction of the high luminance region 501 .

As shown in FIG. 19, the image processing unit 81 obtains the number of pixels (also referred to as the number of pixels in the longitudinal direction) N1 along the first principal component axis 551 of the high luminance region 501 . The image processing unit 81 also obtains the number of pixels along the second principal component axis 552 (also referred to as the number of pixels in the lateral direction) N2 of the high luminance area 501 . Then, the image processing unit 81 obtains the longitudinal size of the imaging plate 10 based on the number N1 of pixels in the longitudinal direction, and obtains the lateral size of the imaging plate 10 based on the number N2 of pixels in the lateral direction.

Here, in this example, a square region with a side of M mm in the detection range R110 of the sensor 41 corresponds to one pixel of the acquired whole image and the binarized image 500 . Mmm is, for example, about 0.03 mm. The image processing unit 81 sets the length obtained by multiplying M mm by the number of pixels N1 in the longitudinal direction as the longitudinal size of the imaging plate 10 . In addition, the image processing unit 81 sets the length obtained by multiplying M mm by the number of pixels N2 in the short side direction as the short side size of the imaging plate 10 . Hereinafter, the lengthwise size and the widthwise size obtained by the image processing unit 81 for the imaging plate 10 may be referred to as the specific lengthwise size and the widthwise size, respectively.

In the size identification process, the image processing section 81 may numerically identify the area of the main surface of the imaging plate 10 (also referred to as the main surface area). In this case, the image processing unit 81 may set the principal surface area of the imaging plate 10 to a value obtained by multiplying the total number of pixels forming the high-brightness region 501 by the square of Mmm. The principal surface area can be said to be the area of the front surface of the imaging plate 10 or the area of the rear surface of the imaging plate 10 . Hereinafter, the main surface area obtained by the image processing unit 81 for the imaging plate 10 may be referred to as a specific main surface area or a specific area.

20 and 21 are diagrams showing examples of the specific longitudinal size, the specific lateral size, and the specific main surface area. FIG. 20 shows the lengthwise size, widthwise size, and main surface area specified based on the binarized image 500 of the pre-reversal whole image 100a shown in FIG. 10 described above. FIG. 21 shows the lengthwise size, widthwise size, and main surface area specified based on the binarized image 500 of the pre-reversal whole image 100a shown in FIG. 11 described above.

Here, FIGS. 10 and 11 show a pre-reversal whole image 100a obtained by irradiating the imaging plate 10 slightly tilted from the reference posture with the excitation light L1. FIG. 20 also shows the IP tilt angle specified from the binarized image 500 of the pre-reversal whole image 100a shown in FIG. 10, and FIG. The IP tilt angle identified from the binarized image 500 is also shown.

As can be understood from FIGS. 20 and 21, when the unexposed area image 103a is not included in the pre-reversal overall image 100a, the specific longitudinal size, the specific lateral size, and the specific main surface area, and the pre-reversal overall image 100a are unexposed. When the area image 103a is included, the specific longitudinal size, the specific lateral size, and the specific main surface area are substantially the same. The image processing unit 81 can appropriately specify the longitudinal size, the lateral size, and the main surface area of the imaging plate 10 regardless of whether the unexposed area image 103a is included in the pre-reversal whole image 100a. .

The image processing unit 81 may specify the type of size of the imaging plate 10 in the size specifying process. In this example, a plurality of sizes are prepared as the size of the imaging plate 10 . In the reading device 1, the holding section 20 can hold each of the imaging plates 10 of different sizes. The reading device 1 can read radiation images from each of the imaging plates 10 of a plurality of sizes.

FIG. 22 is a diagram showing an example of types of sizes of the imaging plate 10 (also referred to as types of IP sizes). As types of IP size, for example, four types of size 0, size 1, size 2, and size 3 are prepared. Here, the short side size and the long side size of the imaging plate 10 in each kind of size are called the nominal short side size and the nominal long side size, respectively.

The nominal short side size and nominal long side size of size 0 are 22 mm and 31 mm, respectively. The nominal short side size and nominal long side size of size 1 are 24 mm and 40 mm, respectively. The nominal short side size and nominal long side size of size 2 are 31 mm and 41 mm, respectively. The nominal hand size and nominal longitudinal size of size 3 are 27 mm and 54 mm, respectively. A value obtained by multiplying the nominal width size and the nominal length size is called a nominal main surface area or a nominal area.

The image processing unit 81 identifies the type of size of the imaging plate 10 based on, for example, the specific lateral size, the specific longitudinal size, and the specific main surface area of the imaging plate 10 . For example, if the specific width size is close to the nominal width size of size 0, the specific length size is close to the nominal length size of size 0, and the specific area is close to the nominal size of size 0, the image processing unit 81 determines that the IP size type is size 0.

For example, the image processing unit 81 uses a first threshold that is slightly smaller than the nominal short length size of size 0 and a second threshold that is slightly larger than the nominal short length size of size 0 to determine the specific short length. Determine whether the size is close to the nominal short side size of size 0. For example, when the specific short length size is larger than the first threshold value and smaller than the second threshold value, the image processing unit 81 determines that the specific short length size is close to the nominal short length size of size 0. .

Further, the image processing unit 81 uses, for example, a third threshold that is slightly smaller than the nominal longitudinal size of size 0 and a fourth threshold that is slightly larger than the nominal longitudinal size of size 0, to determine the specified longitudinal size. is close to the nominal longitudinal size of size 0. For example, when the specific longitudinal size is larger than the third threshold value and smaller than the fourth threshold value, the image processing unit 81 determines that the specific longitudinal size is close to the nominal longitudinal size of size 0.

Further, the image processing unit 81 uses, for example, a fifth threshold that is slightly smaller than the nominal area of size 0 and a sixth threshold that is slightly larger than the nominal area of size 0, to determine whether the specific area is size 0. is close to the nominal area of For example, when the specific area is larger than the fifth threshold and smaller than the sixth threshold, the image processing section 81 determines that the specific area is close to the nominal area of size 0.

Similarly, the image processing unit 81 determines, for example, that the specific transverse size is close to the nominal transverse size of size 1, the specific longitudinal size is close to the nominal longitudinal size of size 1, and the specific principal surface area is the nominal principal surface of size 1. If it is close to the area, it is determined that the type of IP size is size 1.

Similarly, the image processing unit 81 determines, for example, that the specific transverse size is close to the nominal transverse size of size 2, the specific longitudinal size is close to the nominal longitudinal size of size 2, and the specific principal surface area is the nominal principal surface of size 2. If it is close to the area, it is determined that the type of IP size is size 2.

Similarly, the image processing unit 81 determines, for example, that the specific transverse size is close to the nominal transverse size of size 3, the specific longitudinal size is close to the nominal longitudinal size of size 3, and the specific principal surface area is the nominal principal surface of size 3. If it is close to the area, it is determined that the type of IP size is size 3.

10 and 11 show a pre-inversion whole image 100a obtained by irradiating the size 2 imaging plate 10 with the excitation light L1. Therefore, the specific short side size and specific long side size shown in FIGS. 21 and 22 are close to the nominal short side size and nominal long side size of the size 2 imaging plate 10, respectively. Therefore, when the type of IP size is specified based on the pre-reversal whole image 100a shown in FIGS. 10 and 11, size 3 is specified.

The size specifying process as described above may be executed during the series of processes shown in FIG. 14 described above, or may be executed at a timing different from the process shown in FIG. In addition, the display unit 3 may display at least one of the short size, the long size, the main surface area, and the IP size specified by the image processing unit 81, for example. In this case, the display unit 3 may display at least one of the width size, length size, main surface area, and IP size at the same time as the acquired overall image in step s7 described above. may be displayed when is not displayed. In addition, the display unit 3 may display at least one of the width size, length size, main surface area, and IP size at the same time as the IP tilt angle, or may display it when the IP tilt angle is not displayed. may Moreover, the display unit 3 may simultaneously display at least two of the width size, length size, main surface area, and IP size.

Thus, in this example, the image processing unit 81 identifies the IP size based on the image signal as the detection result of the emitted light L2 from the imaging plate 10 and the reflected light, and thus identifies the IP tilt angle. IP size can be appropriately specified as well. As described above, even if the imaging plate 10 includes an unexposed portion, the high-brightness region 501 of the binarized image 500 corresponds to the portion corresponding to the IP of the entire image before reversal. 81 can appropriately specify the width size, length size, main surface area, and type of IP size of the imaging plate 10 .

FIG. 23 is a flowchart showing an example of a series of operations of the image processing section 81 when the image processing section 81 specifies the IP tilt angle and the IP size. The series of processes shown in FIG. 23 may be executed during the series of processes shown in FIG. 14 described above, or may be executed at a different timing than the processes shown in FIG.

As shown in FIG. 23, in step s11, the image processing section 81 binarizes the pre-inversion whole image based on the pre-inversion image signal to generate a binarized image 500. As shown in FIG. Next, in step s12, the image processing section 81 identifies the main surface area of the imaging plate 10 based on the binarized image 500 as described above. Next, in step s13, the image processing unit 81 performs principal component analysis using the positions of a plurality of pixels forming the high-brightness region 501 included in the binarized image 500 as data to be analyzed. A first principal component axis and a second principal component axis are obtained.

Next, in step s14, the image processing unit 81 calculates the IP tilt angle and the width size of the imaging plate 10 based on the binarized image 500, the first principal component axis, and the second principal component axis, as described above. and specify the longitudinal size. Next, in step s15, the image processing unit 81 determines whether or not the type of IP size is size 3 based on the specific width size, the specific length size, and the specific area. In step s15, for example, the image processing unit 81 determines that the specific width size is close to the nominal width size of size 3, the specific length size is close to the nominal length size of size 3, and the specific area is size 3 If it is close to the nominal area of , it is determined that the type of IP size is size 3.

If the determination in step s15 is YES, the process shown in FIG. 23 ends. On the other hand, if NO is determined in step s15, step s16 is executed. In step s16, the image processing unit 81 determines whether the type of IP size is size 2 based on the specific width size, the specific length size, and the specific area. In step s16, the image processing unit 81, for example, as described above, determines that the specified lateral size is close to the nominal lateral size of size 2, the specified longitudinal size is close to the nominal longitudinal size of size 2, and the specified area is close to the nominal longitudinal size of size 2. If it is close to the nominal area of , it is determined that the type of IP size is size 2.

If YES is determined in step s16, the process shown in FIG. 23 ends. On the other hand, if NO is determined in step s16, step s17 is executed. In step s17, the image processing unit 81 determines whether the type of IP size is size 1 based on the specific width size, the specific length size, and the specific area. In step s17, the image processing unit 81, for example, as described above, determines that the specified lateral size is close to the nominal lateral size of size 1, the specified longitudinal size is close to the nominal longitudinal size of size 1, and the specified area is size 1. If it is close to the nominal area of , it is determined that the type of IP size is size 1.

If YES is determined in step s17, the process shown in FIG. 23 is terminated. On the other hand, if NO is determined in step s17, step s18 is executed. In step s18, the image processing unit 81 determines that the type of IP size is size 0. After execution of step s18, the process shown in FIG. 23 ends. In step s18, the image processing unit 81 determines whether the type of IP size is size 0 based on the specific width size, length size, and area, as in steps s15 to s17. may

In the above example, the image processing unit 81 identifies the type of IP size based on the specific width size, the specific length size, and the specific area. Based on one, it is also possible to specify the type of IP size. As shown in FIG. 22, in this example, the nominal width sizes are different from each other, and the nominal length sizes are also different from each other among a plurality of types of sizes. Also, the nominal areas are different between the plural kinds of sizes. The image processing unit 81 may set the size type of the imaging plate 10 to the type having the nominal short side size closest to the specific short side size among the sizes 0 to 3. FIG. Further, the image processing unit 81 may set the type of the imaging plate 10 having the nominal longitudinal size closest to the specific longitudinal size among sizes 0 to 3 as the size type of the imaging plate 10 . Further, the image processing unit 81 may set the type of the imaging plate 10 having a nominal area closest to the specific area among sizes 0 to 3 as the size type of the imaging plate 10 .

Also, the image processing unit 81 may specify the type of IP size based on any two of the specified widthwise size, the specified lengthwise size, and the specified area. For example, when the specific width size is close to the nominal width size of size 1 and the specific length size is close to the nominal length size of size 1, the image processing unit 81 determines that the type of IP size is size 1. good too.

In the size specifying process, the longitudinal size of the imaging plate 10 may not be specified, the lateral size of the imaging plate 10 may not be specified, and the main surface area of the imaging plate 10 may not be specified. good too. Also, in the size identification process, the type of size of the imaging plate 10 may not be identified.

<Irradiation of Excitation Light to Erased Imaging Plate>
In the reader 1, the light source 30 irradiates the erased imaging plate 10 with the excitation light L1, the detector 40 detects the reflected light of the excitation light L1 from the erased imaging plate 10, and the imaging plate 10 is A reflected light image may be acquired. In this case, in this example, the detector 40 also detects reflected light of the excitation light L1 from the IP outer region R130. In this example, the detector 40 detects reflected light of the excitation light L1 from the erased imaging plate 10 and the IP outer region R130, and outputs an image signal as the detection result. An example of the operation of the reading device 1 for irradiating the erased imaging plate 10 with the excitation light L1 will be described below.

Hereinafter, an image signal obtained by detecting the emitted light L2 and the reflected light when the imaging plate 10 for recording a radiation image is held will be referred to as an image signal during emission, like the image signal described above. Further, like the acquired whole image described so far, the whole image including the radiographic image, that is, the whole image based on the image signal at the time of light emission is called the whole image at the time of light emission. In addition, the above-described pre-inversion whole image and post-inversion whole image are referred to as a pre-inversion luminous whole image and post-inversion luminous whole image, respectively.

Further, an image signal as a detection result of reflected light when the erased imaging plate 10 is held is called an erased image signal. Further, the entire image based on the erased image signal is referred to as an erased entire image. In this example, the entire image at the time of erasing includes not only the reflected light image of the imaging plate 10, that is, the reflected light image based on the detection of the reflected light of the excitation light L1 on the imaging plate 10, but also the IP outer area image, Radiographic images are not included. It can also be said that the erasing overall image is a reflected light image of the detection range R110 of the sensor 41 . A reflected light image of the imaging plate 10 is sometimes called an IP reflected light image. Further, hereinafter, the reader 1 will be described with the entire image based on the image signal output by the detector 40 as the light detection result being the acquired overall image. In the following description, the acquired overall image is a concept including the illuminated overall image and the erased overall image.

FIG. 24 is a flow chart showing an example of the operation of the reader 1 of this example. When the start button included in the operation unit 4 is operated, the reader 1 executes the above steps s1 to s4 as shown in FIG. In the reading process of step s2, the detector 40 outputs a light emission image signal as a detection result of the light emission light L2 and the reflected light.

After the erasing process in step s4, in step s21, the driving section 50 moves the holding section 20 holding the erased imaging plate 10 to the reading start position. Then step s22 is executed. In step s22, light source 30 irradiates excitation light L1 to the front surface and IP outer region of erased imaging plate 10. FIG. Then, the detector 40 detects the reflected light of the excitation light L1 from the front surface and IP outer region of the erased imaging plate 10, and outputs an erasing image signal as the detection result. The erasure image signal is, for example, a grayscale image signal similar to the light emission image signal.

After step s22, steps s5 and s6 described above are performed to eject the erased imaging plate 10 to the outlet 2b of the housing 2. FIG. Next, in step s27, the display control unit 82 causes the display unit to display the entire image during light emission based on the image signal during light emission obtained in step s2 and the entire image during erasure based on the image signal during erasure obtained in step s22. 3 simultaneously and separately. In step s27, the image processing unit 81 displays, for example, a grayscale display of the whole image at the time of light emission and the whole image at the time of erasing.

Note that step s27 may be executed at any time after step s22. For example, step s27 may be performed between steps s22 and s5. Further, the entire image during light emission and the entire image during erasing do not have to be displayed at the same time. Also, in step s27, the entire image during light emission may not be displayed. At least one of the size identification process and the inclination angle identification process described above may be executed during the series of processes in FIG. 24, or may be executed at a different timing than the process in FIG.

The erased image signal output by the detector 40 includes the luminance values of a plurality of pixels forming the IP reflected light image and the luminance values of a plurality of pixels forming the IP outer region image. The luminance value included in the erased image signal indicates a larger value as the intensity of the reflected light detected by the detector 40 increases. Therefore, for example, when the intensity of the reflected light in a certain area of the erased imaging plate 10 is high, the brightness of the reflected light image of the certain area included in the erased image signal is high.

FIG. 25 is a schematic diagram showing an example of an erasing overall image 200. As shown in FIG. As shown in FIG. 25 , the erased whole image 200 includes an IP reflected light image 201 and an IP outer area image 202 . In the example of FIG. 25 , the IP reflected light image 201 shows the front surface of the imaging plate 10 . Since the IP reflected light image 201 is a portion corresponding to the imaging plate 10 in the erased entire image 200, the IP reflected light image is also called an IP corresponding portion.

The image processing unit 81 performs image processing on the erasing image signal. In this example, in the image processing for the erasure image signal, unlike the image processing for the light emission image signal, for example, luminance inversion processing is not performed. Therefore, in the erasing image signal after image processing, similarly to the erasing image signal before image processing, if the intensity of the reflected light in a certain area of the imaging plate 10 is high, the luminance value of the reflected light image in the certain area is becomes larger. On the other hand, when the intensity of the reflected light in a certain area of the imaging plate 10 is low, the luminance value of the reflected light image in the certain area is small. Hereinafter, the erased whole image 200 based on the erased image signal that has been subjected to image processing that does not include the luminance inversion process may be referred to as the erased whole image 200 before inversion.

In step s27, the display control unit 82 may cause the display unit 3 to display, for example, the post-reversal light emission entire image 100b and the pre-reversal erasing entire image 200 in grayscale. In this case, the display unit 3 displays the post-reversal light emitting overall image 100b in grayscale as shown in FIGS. Image 200 may be displayed.

FIGS. 26 and 27 are schematic diagrams showing an example of how the post-reversal luminous image 100b and the pre-reversal erasing image 200 are displayed on the display surface 3a of the display unit 3. FIG. FIG. 26 shows an entire image 100b during light emission after reversal and an entire image 200 during erasure before reversal when the imaging plate 10 does not include an unexposed portion. FIG. 27 shows an entire image 100b during light emission after reversal and an entire image 200 during erasing before reversal when the imaging plate 10 includes an unexposed portion.

As shown in FIGS. 26 and 27 , the display unit 3 may display the after-reversal luminescence entire image 100b and the pre-reversal erasing overall image 200 in the same size, for example, or may display them side by side. good too. In this example, the display unit 3 displays the image brighter as the luminance value of the image increases. Therefore, in the whole image 100b at the time of light emission after reversal, for example, the portion where the teeth appear and the unexposed area image 103b are displayed brightly. be done. In addition, in the pre-reversal erasing entire image 200, the portion where the imaging plate 10 is shown is displayed brightly.

Also, as shown in FIGS. 26 and 27, an entire image 200 upon erasing before reversal when the imaging plate 10 includes an unexposed portion, and an erased before reversing image 200 when the imaging plate 10 does not include an unexposed portion. The overall image 200 is the same. The user can confirm the appearance of the imaging plate 10 from the pre-reversal erasing whole image 200 (in other words, the erasing whole image) displayed on the display unit 3 . It should be noted that the method of displaying the post-reversal luminous image 100b and the pre-reversal erasing entire image 200 is not limited to the examples of FIGS.

In the example of FIG. 24 described above, the detector 40 detects the emitted light L2 from the imaging plate 10 excited by the excitation light L1 from the light source 30, and outputs an image signal during emission as the detection result. After that, after the radiation image is erased from the imaging plate 10, the erased imaging plate 10 is irradiated with the excitation light L1 from the light source 30, and the detector 40 detects the reflected light of the excitation light L1 from the imaging plate 10. do. Accordingly, the reader 1 can easily obtain both the radiation image recorded on the imaging plate 10 and the reflected light image of the imaging plate 10 using the same light source 30 and the same detector 40 .

26 and 27, when the entire image at the time of lighting and the whole image at the time of erasing are displayed simultaneously and separately, the user can easily compare the whole image at the time of lighting and the whole image at the time of erasing. Become. In other words, the user can easily compare the radiation image read from the imaging plate 10 and the appearance of the imaging plate 10 . Thereby, for example, the user can easily specify that the imaging plate 10 includes an unexposed portion. This point will be explained below.

If the imaging plate 10 includes an unexposed portion, there is no radiation image in the region corresponding to the unexposed portion in the entire image during light emission. However, the user may suspect that a radiographic image originally exists in the area and that the radiographic image does not exist in the area due to a malfunction of the reading device 1 or that the imaging plate 10 includes an unexposed portion. It is difficult to determine whether or not there is a radiographic image in the region only by displaying the entire image during light emission. On the other hand, as in the example of FIG. 27, when the luminous whole image and the erased holistic image are displayed simultaneously and separately, the user can read from the imaging plate 10 from the display of the luminous whole image. By confirming the radiation image obtained, confirming the appearance of the imaging plate 10 from the display of the entire image at the time of erasing, and comparing the two, it is possible to easily specify that the imaging plate 10 includes an unexposed portion. can. Also, the user can easily specify the range of the unexposed portion on the imaging plate 10 .

In the above example, the image processing unit 81 specifies the IP tilt angle based on the entire image at the time of light emission. A tilt angle may be specified. Similarly, the image processing unit 81 may specify the IP size based on the erasing overall image.

The image processing unit 81 can specify the IP tilt angle and the IP size based on the erasing overall image in the same manner as the IP tilt angle and the IP size based on the emitting overall image. Specifically, the image processing unit 81 binarizes the pre-reversal erasing entire image 200 to generate a binarized image. This binarized image is sometimes called a second binarized image. The threshold value for binarizing the pre-reversal erased entire image 200 is, for example, greater than the luminance value of the IP outer region image 202 included in the pre-inverted erased entire image 200, and the pre-inverted erased entire image. 200 is set to be smaller than the luminance value of the IP reflected light image 201 included in 200 . As a result, the second binarized image becomes the same as the binarized image of the entire image during light emission before inversion, and in the second binarized image, the region corresponding to the IP outer region becomes a low luminance region, and imaging A region corresponding to the plate 10 becomes a high brightness region. The outline of the high-brightness region of the second binarized image has a shape corresponding to the outline of the imaging plate 10 even if the imaging plate 10 includes an unexposed portion. Based on the second binarized image, the image processing unit 81 determines the IP tilt angle, the widthwise size, the lengthwise size, the main surface area of the imaging plate 10, and the type of the IP size in the same manner as described above. can be specified.

FIG. 28 shows the lateral size, longitudinal size, and main surface area of the imaging plate 10 specified based on the second binarized image obtained by binarizing the pre-reversal erasing entire image 200 shown in FIG. and an IP tilt angle. A pre-reversal erasing overall image 200 shown in FIG. 25 is an erasing overall image obtained when the imaging plate 10 of size 2 is irradiated with the excitation light L1. As shown in FIG. 28, the short size and long size specified from the pre-reversal erasing entire image 200 shown in FIG. 25 are close to the nominal short size and long size of the size 2 imaging plate 10, respectively. value.

As described above, even when the erasing image signal representing the reflected light image of the imaging plate 10 is used to specify the IP tilt angle, the IP tilt angle can be properly identified. Also, even when the erasure image signal is used to identify the IP size, the IP size can be appropriately identified in the same manner as when the light emission image signal is used.

<Correction of inclination of IP equivalent part>
When the imaging plate 10 is tilted from the reference posture, as shown in FIG. 16 and the like, the portion corresponding to the IP is tilted in the acquired overall image. Specifically, when the imaging plate 10 is tilted clockwise from the reference posture, the longitudinal direction of the portion corresponding to the IP is the direction corresponding to the sub-scanning direction DRs in the acquired whole image (the longitudinal direction of the whole image 100a before reversal in FIG. direction). On the other hand, when the imaging plate 10 is tilted counterclockwise from the reference posture, the longitudinal direction of the portion corresponding to IP is tilted counterclockwise with respect to the direction corresponding to the sub-scanning direction DRs in the acquired whole image. If the entire acquired image is displayed with the IP equivalent portion tilted, the user may find it difficult to see the tilted IP equivalent portion.

Therefore, the image processing unit 81 may perform tilt correction processing for correcting the tilt of the portion corresponding to the IP on the obtained entire image based on the IP tilt angle α. When the acquired entire image to be corrected is the emitted entire image based on the detection of the emitted light L2, the tilt correction process corrects the tilt of the portion corresponding to the IP, thereby correcting the tilt of the portion corresponding to the IP. Tilt is corrected. On the other hand, when the acquired whole image to be corrected is the erased whole image based on the detection of the reflected light, the tilt correction process corrects the tilt of the IP reflected light image showing the imaging plate 10 . The image processing unit 81 may perform tilt correction processing on the acquired whole image based on the image signal before the brightness reversal processing is performed, or the acquired whole image based on the image signal after the brightness reversal processing is performed. may be subjected to tilt correction processing. The display unit 3 may display the acquired whole image after the tilt correction process. The tilt correction process may be performed during the series of processes in FIG. 14, or may be performed at a different timing from the process in FIG. Also, the tilt correction process may be executed during the series of processes in FIG. 24, or may be executed at a different timing from the process in FIG. The tilt correction process can be said to be a process of correcting the tilt of the portion corresponding to the IP in the entire image during light emission according to the tilt of the imaging plate 10 from the reference posture.

FIG. 29 is a schematic diagram for explaining an example of tilt correction processing. In FIG. 29, the acquired whole image 250 before the tilt correction process is shown on the upper side, and the acquired whole image 250 after the tilt correction process is shown on the lower side. An acquired whole image 250 to be corrected includes an IP equivalent portion 251 and an IP outer area image 252 . In FIG. 29 , the longitudinal direction DR1 of the IP-corresponding portion 251 is indicated by a dashed line, and the direction DR2 corresponding to the sub-scanning direction DRs in the obtained overall image 250 is indicated by a dashed line.

In the tilt correction process, the image processing unit 81 obtains the center of gravity 251a of the IP equivalent portion 251 included in the acquired entire image 250 to be corrected. Here, the center of gravity 251 a of the IP-corresponding portion 251 coincides with the center of gravity of the high-brightness region of the binarized image of the acquired overall image 250 . The image processing unit 81 generates a binarized image of the obtained overall image 250, and obtains the centroid 251a of the IP-corresponding portion 251 of the obtained overall image 250 by obtaining the centroid of the high luminance area of the generated binarized image. be able to. Next, the image processing unit 81 rotates the obtained entire image 250 by the IP tilt angle α around the obtained center of gravity 251a. At this time, if the IP tilt angle α is positive, the image processing unit 81 rotates the obtained entire image 250 counterclockwise 255L by the IP tilt angle α, as shown in FIG. On the other hand, when the IP tilt angle α is negative, the image processing unit 81 rotates the obtained whole image 250 clockwise by the IP tilt angle α. As a result, the inclination of the IP-corresponding portion 251 is corrected, and the longitudinal direction DR1 of the IP-corresponding portion 251 becomes parallel to the direction DR2 corresponding to the sub-scanning direction DRs in the acquired whole image 250 .

FIG. 30 is a schematic diagram showing an example of a state in which the tilt correction process is performed on the entire image 100a during light emission before reversal shown in FIG. 16 described above. As can be understood by comparing FIG. 16 and FIG. 30, the inclination of the radiation image 101a included in the IP-corresponding portion 105a is appropriately corrected by the inclination correction processing for the whole image 100a during light emission before reversal. The orientation of the IP-corresponding portion 105a in the entire image 100a during light emission before reversal in which the tilt correction processing is performed is the portion corresponding to the IP in the entire image 100a during light emission before reversal obtained when the orientation of the imaging plate 10 is the reference posture. It becomes the same as the posture of 105a. The display unit 3 may display the pre-reversal luminous whole image 100a after the tilt correction process, for example, in a gray scale as shown in FIG. Henceforth, the display of the acquired whole image includes the display of the acquired whole image after the tilt correction processing.

In this manner, the image processing unit 81 corrects the tilt of the IP-corresponding portion of the obtained entire image based on the IP tilt angle, thereby obtaining the IP-corresponding portion whose tilt is appropriately corrected. For example, when tilt correction processing is performed on the entire image during light emission, it is possible to obtain a radiographic image whose tilt is appropriately corrected. Further, when tilt correction processing is performed on the entire image at erasing, it is possible to obtain an IP reflected light image whose tilt is appropriately corrected.

<Regarding extraction processing for the acquired entire image>
The image processing unit 81 determines, based on the IP tilt angle and the IP size, a cutout image to be cut out from the whole image during luminescence including the radiographic image, and cuts out the determined cutout image from the whole image during luminescence. processing may be performed. By this clipping process, a desired clipped image corresponding to the IP tilt angle and IP size can be obtained from the entire image during light emission. The image processing unit 81 functions as a clipping unit that performs clipping processing. The extraction process may be performed during the series of processes in FIG. 14, or may be performed at a different timing from the process in FIG. Also, the extraction process may be executed during the series of processes in FIG. 24, or may be executed at a different timing from the process in FIG.

In the clipping process, for example, a portion corresponding to the IP of the entire image during light emission may be determined as the clipped image. In this case, the image processing unit 81 determines, as a cutout image, the portion corresponding to the IP of the whole image when the light is emitted, based on the type of IP size and the IP tilt angle, for example. An example of the operation of the image processing unit 81 when the image processing unit 81 determines the portion corresponding to the IP of the whole image when the light is emitted as the cutout image will be described below. Hereinafter, the type of IP size specified by the image processing unit 81 may be referred to as a specified size Z. In this example, Z is one of the values 0, 1, 2 and 3.

In the clipping process, the image processing unit 81 sets a clipping frame for the entire image during light emission based on, for example, the type of IP size and the IP tilt angle. Then, the image processing unit 81 determines the portion within the cut-out frame in the whole image when the light is emitted as the cut-out image.

The shape of the cutting frame is similar to the nominal outer shape of the imaging plate 10 of the specific size Z. FIG. In this example, since the outer shape of the imaging plate 10 is a rectangle with rounded corners, the shape of the cutting frame is also a rectangle with rounded corners. The size of the cutting frame in the transverse direction is a value corresponding to the nominal transverse size of the imaging plate 10 of the specific size Z (also referred to as the nominal transverse size of the specific size Z). The size is a value corresponding to the nominal longitudinal size of the imaging plate 10 of the specific size Z (also referred to as the nominal longitudinal size of the specific size Z).

Here, for each type of IP size, the image processing unit 81 grasps in advance how many pixels each of the nominal short side size and the nominal long side size corresponds to in the obtained whole image. When P1 pixels correspond to the nominal short side size of the specific size Z and P2 pixels correspond to the nominal longitudinal size of the specific size Z, the image processing unit 81 adjusts the width of the clipping frame in the width direction. The size is set to the length of P1 pixels, and the size in the longitudinal direction of the clipping frame is set to the length of P2 pixels. For example, when P1=800 and P2=1100, the size of the clipping frame in the short direction is set to the length of 800 pixels, and the size of the clipping frame in the longitudinal direction is set to the length of 1100 pixels. set.

When the image processing unit 81 determines the outer shape and size of the clipping frame, the center of the clipping frame coincides with the center of gravity of the portion corresponding to the IP of the entire image during light emission, and the longitudinal direction and the width direction of the clipping frame are illuminated. The cut-out frame is arranged on the whole image when emitting light so as to be parallel to the longitudinal direction and the width direction of the whole image when emitting light. As described above, the center of gravity of the IP-corresponding portion of the whole image during light emission coincides with the center of gravity of the high luminance area of the binarized image of the whole image during light emission.

Next, the image processing unit 81 rotates the clipping frame arranged on the entire image during light emission by the IP tilt angle around the center of gravity of the IP corresponding portion. At this time, the image processing unit 81 rotates the clipping frame clockwise when the IP tilt angle is positive, and rotates the clipping frame counterclockwise when the IP tilt angle is negative. As a result, the portion within the cut-out frame of the entire image at the time of light emission matches the portion corresponding to the IP. The image processing unit 81 determines, as a cut-out image, a portion within the cut-out frame rotated by the IP tilt angle in the entire image during light emission. After that, the image processing unit 81 cuts out the determined cutout image from the whole image at the time of light emission. As a result, the portion corresponding to the IP is cut out from the entire image during light emission, and an image of only the portion corresponding to the imaging plate 10 can be obtained. The cropping process may be performed on the whole image when the light is emitted before reversal, or may be performed on the whole image when the light is emitted after the reversal.

FIG. 31 is a schematic diagram showing an example of how the cutout frame 150 is set for the whole image 100b at the time of light emission after reversal shown in FIG. 12 described above. FIG. 32 is a schematic diagram showing an example of how a clipped image 151 in the clipping frame 150 in the whole image 100b when emitting light after reversal is clipped from the whole image 100b when emitting light after reversal in the example of FIG. be. As shown in FIG. 32, the IP-corresponding portion 105b is appropriately cut out from the whole image 100b at the time of light emission after reversal. The cut-out image 151 includes a radiographic image 151a that is the same as the radiographic image 101b included in the post-reversal light emission entire image 100b.

FIG. 33 is a schematic diagram showing an example of how the cutout frame 150 is set for the whole image 100b at the time of light emission after reversal shown in FIG. 13 described above. FIG. 34 is a schematic diagram showing an example of how a cut-out image 151 in the cut-out frame 150 in the whole image 100b during light emission after reversal is cut out from the whole image 100b during light emission after reversal in the example of FIG. . As shown in FIG. 34, even when the post-reversal luminescence entire image 100b includes the unexposed area image 103b, the IP corresponding portion 105b is appropriately cut out from the post-reversal luminescence overall image 100b. The cut-out image 151 includes the same radiation image 151a as the radiation image 101b included in the post-reversal light emission entire image 100b, and the same unexposed area as the unexposed area image 103b included in the post-reversal light emission overall image 100b. Image 151b is included.

When the clipping process is performed, the display unit 3 may display a clipped image 151 clipped from the entire image during light emission. In this case, the display unit 3 may display the clipped image 151 in grayscale as shown in FIGS. It can also be said that FIGS. 32 and 34 are schematic diagrams showing display examples of the cut-out image 151. FIG. When the clipped image 151 is displayed, the user can confirm only a necessary image of the whole image during flash. As in this example, when the portion corresponding to the IP is cut out from the whole image when the light is emitted and displayed as the clipped image 151, the user can confirm only the necessary portion corresponding to the IP in the whole image when the light is emitted. . Thereby, the user can easily specify that the imaging plate 10 includes an unexposed portion by checking the display of the cutout image 151 as shown in FIG. 34, for example. Also, the user can easily specify the range of the unexposed portion on the imaging plate 10 .

The display unit 3 may simultaneously and separately display the clipped image 151 clipped from the entire image at the time of light emission and the overall image 200 at the time of erasure. FIG. 35 is a schematic diagram showing an example of a state in which the clipped image 151 and the erased whole image 200 are displayed in gray scale on the display surface 3a of the display section 3. As shown in FIG. FIG. 35 shows a cutout image 151 including an unexposed area image 151b. As shown in FIG. 35, the display unit 3 displays a cutout image 151 and an erased whole image 200, for example, an IP reflected light image (IP corresponding portion) 201 of the cutout image 151 and an erased whole image 200. You may display so that it may become the same size. Further, the display unit 3 may display the cut-out image 151 and the erased whole image 200 side by side, for example. The user can easily compare the cutout image 151 and the erased whole image 200 by simultaneously and separately displaying the cutout image 151 and the erased whole image 200 on the display unit 3 . Thereby, for example, the user can compare the IP reflected light image 201 and the clipped image 151 included in the entire image 200 at the time of erasing to determine whether or not the portion corresponding to the IP has been appropriately extracted from the overall image at the time of emission. can be easily identified.

The image processing unit 81 may correct the tilt of the cutout image 151 cut out from the entire image during light emission based on the IP tilt angle, in the same manner as in the tilt correction processing described above. As a result, for example, when the corrected cut-out image 151 is displayed, the user can easily see the cut-out image 151 . Hereinafter, it is assumed that the tilt correction processing also includes correcting the tilt of the cut-out image 151 .

The image processing unit 81 corrects the tilt of the cut-out image 151 in the same manner as the above-described tilt correction processing for the entire image during light emission, for example. Specifically, the image processing unit 81 first obtains the center of gravity of the cutout image 151 . The center of gravity of the clipped image 151 coincides with the center of gravity of the high-brightness region of the binarized image of the entire image during illumination. Therefore, the image processing unit 81 can obtain the center of gravity of the clipped image 151 by obtaining the center of gravity of the high-luminance region of the binarized image of the whole image when the light is emitted. Next, the image processing unit 81 rotates the cutout image 151 by the IP tilt angle around the obtained center of gravity. At this time, if the IP tilt angle is positive, the image processing unit 81 rotates the cutout image 151 counterclockwise by the IP tilt angle. On the other hand, when the IP tilt angle is negative, the image processing unit 81 rotates the cutout image 151 clockwise by the IP tilt angle. As a result, the tilt of the cutout image 151 is corrected. Therefore, the tilt of the radiographic image based on the image signal at the time of light emission, which is included in the cutout image 151, is corrected.

FIGS. 36 to 38 are schematic diagrams showing an example of how the clipping process is performed on the whole image when the light is emitted, and then the tilt correction process is performed on the clipped image 151. FIG. In the examples of FIGS. 36 to 38, the cropping process is performed on the whole image 100a at the time of light emission before reversal shown in FIG. 16 described above. As shown in FIG. 36, the image processing unit 81 sets the clipping frame 150 to the whole image 100a during light emission before reversal as described above. Next, the image processing unit 81 cuts out a cutout image 151 within the cutout frame 150 in the whole image 100a during light emission before reversal, as shown in FIG. Thereafter, as shown in FIG. 38, the image processing unit 81 corrects the tilt of the clipped image 151 based on the IP tilt angle. As a result, the tilt of the cutout image 151 corresponding to the tilt of the imaging plate 10 from the reference posture is appropriately corrected. The orientation of the cut-out image 151 whose tilt has been corrected is the same as the orientation of the cut-out image 151 obtained when the orientation of the imaging plate 10 is the reference orientation.

In the above example, the image processing unit 81 uses the portion corresponding to the IP of the whole image when the light is emitted as the clipped image 151 . An example of the operation of the image processing section 81 in this case will be described below.

FIG. 39 is a schematic diagram showing another example of the holding section 20 that holds the imaging plate 10. As shown in FIG. FIG. 39 shows that each fixing portion 22a of the fixing portion 22 of the holding portion 20 exists at the approach position. In the holding portion 20 (also referred to as holding portion 20A) shown in FIG. 39, the holding portion 22 has an overlapping portion 220 that covers the peripheral portion 10a of the imaging plate 10 when each fixing portion 22a is in the approached position. Each fixed portion 22a has an overlapping portion 220a that covers the peripheral edge 10a of the imaging plate 10 when in the approximated position. The overlapping portion 220 of the fixing portion 22 is composed of overlapping portions 220a of a plurality of fixing portions 22a.

When the imaging plate 10 is held by the holding portion 20A, the peripheral edge portion 10a of the imaging plate 10 is covered with the overlapping portion 220 of the fixing portion 22. Therefore, in the reading device 1, the entire image in which the overlapping portion 220 is reflected is captured. can get.

FIG. 40 is a schematic diagram showing an example of an entire image 100a during light emission before reversal obtained when the imaging plate 10 is held by the holding portion 20A. An image 120 of the overlapping portion 220 of the fixing portion 22 (also referred to as an overlapping partial image 120) is included in the whole image 100a at the time of light emission before reversal shown in FIG. The overlapping partial image 120 is an image based on detection of the reflected light of the excitation light L<b>1 from the overlapping portion 220 . The overlapping partial image 120 is composed of images 120a (also referred to as overlapping partial images 120a) of overlapping portions 220a of a plurality of fixed portions 22a. In this example, the surface of each fixing portion 220a is subjected to black alumite treatment, for example. Therefore, the luminance value of the overlapping partial image 120 included in the whole image 100a during light emission before inversion is reduced.

When the overlapping partial image 120 is included in the luminous whole image, the image processing unit 81 controls the cutout image 151 not to include the overlapping partial image 120 (in other words, a plurality of overlapping partial images 120a) in the luminous whole image. , a portion corresponding to IP may be determined as the cutout image 151 . In this case, the image processing unit 81, for example, similarly to the above, sets the clipping frame 150 to the entire image during light emission based on the type of IP size and the IP tilt angle. Since the outer shape of the clipping frame 150 set as described above forms a shape corresponding to the outer shape of the imaging plate 10, the overlapping partial image 120 is included in the clipping frame 150 at this point. FIG. 41 is a schematic diagram showing an example of how the cutout frame 150 is set as described above with respect to the whole image 100a at the time of light emission before reversal shown in FIG. A plurality of overlapping partial images 120a forming an overlapping partial image 120 are included in the cutout frame 150 set in the whole image 100a during light emission before reversal.

After setting the clipping frame 150 to the entire image during light emission as described above, the image processing unit 81 sets the clipping frame 150 to, for example, a similar shape so that the overlapping partial image 120 is not included in the clipping frame 150 . to zoom out. At this time, the image processing unit 81 reduces the clipping frame 150 in a similar shape so that the overlapping partial image 120 is not included in the clipping frame 150 and the clipping frame 150 after reduction is as large as possible. do. For example, the image processing unit 81 can specify the position and range of each overlapping partial image 120a in the luminous overall image based on the binarized image of the luminous overall image. Then, based on the position and range specified for each overlapping partial image 120a, the image processing unit 81 prevents the overlapped partial image 120 from being included in the clipping frame 150 and reduces the clipping frame 150 after reduction as much as possible. The clipping frame 150 is reduced in a similar shape so as to become larger. Then, the image processing unit 81 determines a portion within the reduced cutout frame 150 as the cutout image 151 in the entire image during light emission. As a result, a cutout image 151 that does not include the overlapping partial image 120 and includes most of the IP corresponding portion 105a is obtained. FIG. 42 is a schematic diagram showing an example of how the clipping frame 150 shown in FIG. 41 is reduced. As shown in FIG. 42 , the image processing unit 81 determines a portion within the reduced cutout frame 150 as the cutout image 151 in the entire image 100a during light emission before reversal.

After determining the cut-out image 151, the image processing unit 81 cuts out the cut-out image 151 from the whole image at the time of light emission. FIG. 43 is a schematic diagram showing an example of how the clipped image 151 shown in FIG. 42 is clipped from the pre-reversal whole image 100a.

In this way, when the image processing unit 81 determines a portion of the IP equivalent portion as the clipped image 151 so that the clipped image 151 does not include the overlapping partial image 120, the overlapping portion 220 of the fixing unit 22 is A clipped image 151 that is not captured can be obtained. Thereby, for example, when the clipped image 151 is displayed, the user can confirm only the portion corresponding to the imaging plate 10 .

Note that even when the image processing unit 81 cuts out the clipped image 151 in which the overlapping portion 220 does not appear from the entire image during light emission, the tilt of the clipped image 151 is adjusted to the IP tilt angle as described above. can be corrected based on In this case, the display control unit 82 may cause the display unit 3 to display the cropped image 151 whose tilt has been corrected.

FIG. 44 is a schematic diagram showing another example of the whole image 100a at the time of light emission before reversal obtained when the imaging plate 10 is held by the holding portion 20A. FIGS. 45 to 47 are schematic diagrams showing an example of how the pre-reversal luminous whole image 100a shown in FIG. is. Image processing unit 81 sets clipping frame 150 in whole image 100a during light emission before reversal as described above, and then, as shown in FIG. The clipping frame 150 is reduced in a similar shape so that the clipping frame 150 after reduction is as large as possible. Next, the image processing unit 81 cuts out a clipped image 151 within the clipping frame 150 in the whole image 100a during light emission before reversal, as shown in FIG. Thereafter, as shown in FIG. 47, the image processing unit 81 corrects the tilt of the clipped image 151 based on the IP tilt angle. As a result, the tilt of the cutout image 151 corresponding to the tilt of the imaging plate 10 from the reference posture is appropriately corrected.

In this way, the image processing unit 81 determines at least a portion of the portion corresponding to the IP of the entire image at the time of light emission as the cropped image based on the IP size and the IP tilt angle. It can be appropriately cut out from the whole image at the time of light emission.

Even if the overlapped partial image 120 is not included in the whole image when the light is emitted, the image processing unit 81 reduces the cutout frame 150 set in the whole image when the light is emitted to a similar shape, for example, and reduces the whole image when the light is emitted. A later portion within the cutout frame 150 may be determined as the cutout image 151 . Even in this case, a portion of the portion corresponding to the IP in the entire image during light emission is determined as the cutout image 151 . In addition, the image processing unit 81 enlarges the cropped frame 150 set in the entire image during lighting to a similar shape, for example, and determines a portion within the enlarged cropped frame 150 in the total image during lighting as the cropped image 151 . may In this case, the portion corresponding to the IP and its surrounding portion (for example, a portion of the IP outer region image or at least a portion of the overlapping partial image 120) are determined as the cutout image 151 in the entire image during light emission.

In the clipping process, the image processing unit 81 determines a clipped image (also referred to as a second clipped image) to be clipped from the whole image at erasure including the IP reflected light image based on the IP tilt angle and the IP size, The determined second cropped image may be cropped from the erased whole image. In this case, the image processing unit 81 may determine at least a portion of the IP-corresponding portion (in other words, IP reflected light image) of the erased entire image as the second cut-out image. Further, when the image of the overlapping portion 220 is included in the erased whole image, the image processing section 81 determines the second cut-out image so that the image of the overlapping portion 220 is not included in the second cut-out image. good too. Further, the display control unit 82 may cause the display unit 3 to display a second clipped image clipped from the entire image at the time of erasure. In this case, the display unit 3 may simultaneously and separately display the second cut-out image and the cut-out image (also referred to as the first cut-out image) 151 cut out from the whole image at the time of light emission. Further, the image processing unit 81 may correct the tilt of the second cropped image based on the IP tilt angle. Further, the display control unit 82 may cause the display unit 3 to display the second cropped image whose tilt has been corrected. In this case, the display unit 3 may display the tilt-corrected second cut-out image and the tilt-corrected first cut-out image simultaneously and separately.

Note that when the imaging plate 10 hardly tilts from the reference posture, the image processing unit 81 determines the first cutout image and the second cutout image based on the IP size without using the IP tilt angle. You may In this case, in the clipping process, the process of rotating the clipping frame according to the IP tilt angle is not required. Henceforth, displaying a cut-out image also includes displaying a cut-out image whose tilt has been corrected.

<Specification of unexposed area image>
The image processing unit 81 may perform an unexposed identification process of identifying an unexposed area image in the first cut-out image 151 or an unexposed area image in the entire image during light emission. The unexposed identification process may be executed during the series of processes in FIG. 14, or may be executed at a timing different from the process in FIG. Also, the unexposed identification process may be executed during the series of processes in FIG. 24, or may be executed at a timing different from the process in FIG. The image processing unit 81 functions as a specifying unit that specifies an unexposed area image.

When at least part of the IP corresponding portion is set to the first cut-out image 151 as in the examples of FIGS. is binarized to generate a binarized image. Here, as shown in FIGS. 32 and 34, the first cut-out image 151 cut out from the whole image 100b at the time of light emission after reversal is referred to as the first cut-out image 151 after reversal. 43 and 46, the first cutout image 151 cut out from the whole image 100a during light emission before reversal is referred to as the first cutout image 151 before reversal.

The threshold used in the binarization of the pre-inversion first cutout image 151 is, for example, smaller than the minimum luminance value of the radiation image included in the pre-inversion first cutout image 151 and It is set to a value greater than the luminance value of the unexposed area image included in the image 151 . For example, consider a case where the minimum luminance value of the radiation image included in the first cutout image 151 before inversion is 10000 and the luminance value of the unexposed area image included in the first cutout image 151 before inversion is 3000. FIG. In this case, the threshold is set to 5000, for example. As a result, in the binarized image of the pre-reversal first cutout image 151, which is at least a part of the IP corresponding portion, the portion corresponding to the unexposed area image becomes a low-luminance region, and the portion corresponding to the radiation image becomes a high-luminance region. area. The image processing unit 81 appropriately specifies the unexposed area image in the first cut-out image 151 before inversion by specifying the low-luminance region in the binarized image of the first cut-out image 151 before inversion. can be done. Note that when the imaging plate 10 does not include an unexposed portion, the binarized image of the pre-inversion first cutout image 151 does not include a low luminance region.

In addition, the threshold value used in the binarization of the post-reversal first cut-out image 151 is, for example, greater than the maximum luminance value of the radiation image included in the post-reversal first cut-out image 151 and It is set to a value smaller than the luminance value of the unexposed area image included in the cutout image 151 . As a result, in the binarized image of the post-reversal first cutout image 151, which is at least part of the IP-corresponding portion, the portion corresponding to the unexposed area image becomes a high-brightness region, and the portion corresponding to the radiation image becomes a low-brightness region. area. The image processing unit 81 appropriately specifies the unexposed area image in the post-inversion first cut-out image 151 by specifying the high-brightness region in the binarized image of the post-inversion first cut-out image 151. can be done.

In this way, when the image processing unit 81 cuts out at least part of the IP-corresponding portion as the first cut-out image 151 from the entire image during light emission, the image processing unit 81 appropriately specifies the unexposed area image in the first cut-out image 151. can do.

In the unexposed identification process, the image processing section 81 may identify an unexposed area image in the first cut-out image 151 including at least one of the IP outer area image and the overlapping partial image 120 . In this case, the image processing unit 81 ternarizes the first cut-out image 151 to generate a ternarized image. Hereinafter, when there is no particular need to distinguish between the IP outer area image and the overlapping partial image 120, they may be referred to as low-reflection area images.

The image processing unit 81 first compares the luminance value of each of the plurality of pixels forming the first cut-out image 151 with preset lower and upper threshold values. The upper threshold is a value greater than the lower threshold. The image processing unit 81 replaces the luminance values of each of the plurality of pixels forming the first cut-out image 151 with the first value if the luminance values are less than the lower threshold value, and increases the luminance values above the lower threshold value. Luminance values below the threshold are replaced with a second value, and luminance values above the upper threshold are replaced with a third value. Here, the third value is greater than the second value, and the second value is greater than the first value. As a result, the first cut-out image 151 is ternarized to obtain a ternarized image. Hereinafter, in a ternary image, an area having a luminance value of the third value will be referred to as a high luminance area, an area having a luminance value of the second value will be referred to as an intermediate luminance area, and an area having a luminance value of the first value will be referred to as a medium luminance area. A certain area is sometimes called a low luminance area.

The lower first threshold value used in the ternarization of the pre-inversion first cutout image 151 is, for example, greater than the luminance value of the low-reflection area image included in the pre-inversion first cutout image 151, and It is set to a value smaller than the luminance value of the unexposed area image included in the first cut-out image 151 before inversion. The upper threshold value used in the ternarization of the pre-inversion first cut-out image 151 is, for example, greater than the luminance value of the unexposed area image included in the pre-inversion first cut-out image 151 and It is set to a value smaller than the minimum luminance value of the radiographic image included in one cut-out image 151 . For example, the minimum luminance value of the radiation image included in the first cut-out image before reversal 151 is 10000, the luminance value of the unexposed area image included in the first cut-out image before reversal 151 is 3000, and the first cut-out image before reversal is 10000. Consider a case where the luminance value of the low-reflection area image included in 151 is 1000. FIG. In this case, the lower threshold is set to 2000, for example, and the upper threshold is set to 5000, for example. As a result, in the ternary image of the first cut-out image 151 before reversal, the portion corresponding to the low-reflection area image becomes a low-luminance area, and the portion corresponding to the unexposed area image becomes a medium-luminance area, which corresponds to a radiation image. The area where the brightness is high is the high brightness area. The image processing unit 81 appropriately specifies an unexposed area image in the first cut-out image 151 before inversion by specifying a medium luminance region in the ternary image of the first cut-out image 151 before inversion. can be done. Note that when the imaging plate 10 does not include an unexposed portion, the ternary image of the first cut-out image 151 before inversion does not include the intermediate luminance region.

The lower limit threshold used in the ternarization of the post-reversal first cutout image 151 is, for example, greater than the maximum luminance value of the radiation image included in the post-reversal first cutout image 151 and It is set to a value smaller than the luminance value of the unexposed area image included in the cutout image 151 . The upper threshold value used in the ternarization of the post-reversal first cut-out image 151 is, for example, greater than the luminance value of the unexposed area image included in the post-reversal first cut-out image 151, It is set to a value smaller than the brightness value of the low-reflection area image included in one cut-out image 151 . As a result, in the ternary image of the first cut-out image 151 after reversal, the portion corresponding to the low-reflection area image becomes a high-brightness area, and the portion corresponding to the unexposed area image becomes a medium-brightness area, which corresponds to a radiation image. The area where the The image processing unit 81 appropriately specifies an unexposed area image in the post-inversion first cut-out image 151 by specifying a medium luminance region in the ternary image of the post-inversion first cut-out image 151. can be done.

In this manner, the image processing section 81 can appropriately identify the unexposed area image in the first cut-out image 151 including the low-reflection area image.

In the unexposed identification process, the image processing section 81 may identify an unexposed area image in the entire image during light emission. In this case, the image processing unit 81 ternarizes the entire image during light emission to produce a ternarized image in the same manner as when specifying the unexposed area image in the first cut-out image 151 including the low-reflection area image. Generate. The lower threshold value and upper threshold value used in the ternarization of the pre-reversal luminous whole image 100a are the same as the lower threshold value and the upper threshold value used in the ternarization of the pre-reversal first cropped image 151. It is set in the same way as the value. The image processing unit 81 can appropriately specify an unexposed area image in the whole image 100a when emitting light before inversion by specifying a medium luminance area in the ternary image of the whole image 100a when emitting light before inversion. . In addition, the lower limit threshold and upper limit threshold used for ternarizing the post-reversal light emission entire image 100b are the same as the lower limit threshold and upper limit threshold used for ternarizing the post-reversal first cropped image 151. It is set similarly to the threshold. The image processing unit 81 can appropriately specify the unexposed area image in the post-reversal light emission overall image 100b by specifying the intermediate luminance region in the ternary image of the post-reversal light emission overall image 100b. .

When the image processing unit 81 specifies an unexposed area image in the first cut-out image 151 or the whole image when emitting light, the display control unit 82 determines whether the unexposed area image is in the first cut-out image 151 or the whole image when emitting light. The display unit 3 may display the non-exposed notification information 161 for notifying the presence. This allows the user to easily recognize that there is an unexposed area image in the first cut-out image 151 or the whole image at the time of emission. Therefore, the user can easily recognize that the imaging plate 10 includes an unexposed portion.

48 and 49 are schematic diagrams showing display examples of the non-exposure notification information 161. FIG. In the example of FIG. 48 , a first cut-out image 151 including a radiation image 151 a and an unexposed area image 151 b and unexposed notification information 161 are displayed on the display surface 3 a of the display section 3 . In the example of FIG. 49, the entire image 100b at the time of light emission after reversal and the non-exposure notification information 161 are displayed on the display surface 3a. In the example of FIG. 48, a border line 1510 bordering the range of the unexposed area image 151b is displayed as the unexposed notification information 161 for notifying that the unexposed area image 151b exists in the first cut-out image 151. . Similarly, in the example of FIG. 49, the border line 1030 bordering the range of the unexposed area image 103b is used as the unexposed notification information 161 for notifying that the unexposed area image 103b exists in the post-reversal light emission entire image 100b. is displayed. Border lines 1510 and 1030 may be colored in at least one color.

The non-exposure notification information 161 is not limited to the examples in FIGS. For example, hatching such as oblique lines attached to the unexposed area image may be displayed as the unexposed notification information 161 . Further, the unexposed notification information 161 may be displayed by displaying the unexposed area image in at least one color.

Further, as shown in FIG. 50 , a frame-shaped figure 1511 surrounding the first cut-out image 151 may be displayed as the non-exposure notification information 161 . In the example of FIG. 50, the frame-shaped figure 1511 is hatched for convenience of explanation, but the frame-shaped figure 1511 may not be hatched or may be hatched. Also, the frame-shaped figure 1511 may be displayed in at least one color. Similarly, when an unexposed area image is identified in the entire image during light emission, a frame-shaped figure surrounding the overall image during light emission may be displayed as the unexposed notification information 161 . Also, the non-exposure notification information 161 may be displayed in at least one of characters and symbols.

If the first cut-out image 151 or the entire image during emission does not include the unexposed area image, that is, the image processing unit 81 specifies the unexposed area image in the first cut-out image 151 or the entire image during emission. If not, the display control unit 82 may cause the display unit 3 to display notification information 162 that notifies that there is no unexposed area image in the first cut-out image 151 or the whole image at the time of emission. Thereby, the user can easily recognize that the imaging plate 10 does not include an unexposed portion.

FIG. 51 is a schematic diagram showing a display example of the notification information 162. As shown in FIG. FIG. 51 shows a display example of notification information 162 that notifies that there is no unexposed area image in the first cut-out image 151 . In the example of FIG. 51 , a frame-shaped figure 1512 surrounding the first cut-out image 151 that does not include the unexposed area image is displayed as the notification information 162 . In the example of FIG. 51, the frame-shaped figure 1512 is hatched for convenience of explanation, but the frame-shaped figure 1512 may not be hatched or may be hatched. Also, the frame-shaped figure 1512 may be displayed in at least one color. When the frame-shaped figure 1511 of FIG. 50 is displayed as the unexposed notification information 161, the frame-shaped figure 1511 as the unexposed notification information 161 and the frame-shaped figure 1512 as the notification information 162 are different from each other. Is displayed. At this time, the frame-shaped figure 1511 and the frame-shaped figure 1512 may be displayed in different colors. In addition, the frame-shaped figure 1511 and the frame-shaped figure 1512 may have different hatching. Similarly, when an unexposed area image does not exist in the whole image when the light is emitted, a frame-shaped figure surrounding the whole image when the light is emitted may be displayed as the notification information 162 . Also, the notification information 162 may be displayed using at least one of characters and symbols.

As shown in FIG. 35, the display control unit 82 causes the display unit 3 to simultaneously and separately display the first cut-out image 151 and the erased whole image 200. In this case, the first cut-out image When the unexposed area image is included in 151, the unexposed notification information 161 may also be displayed on the display unit 3 as shown in FIG. At this time, the second cropped image may be displayed instead of the erased whole image 200 . Further, as shown in FIG. 27 described above, the display control unit 82 causes the display unit 3 to simultaneously and separately display the whole image at the time of light emission and the whole image at the time of erasure 200. When an unexposed area image is included, unexposed notification information 161 may be displayed together on the display unit 3 as shown in FIG. At this time, the second cropped image may be displayed instead of the erased whole image 200 .

In addition, when the display control unit 82 causes the display unit 3 to simultaneously and separately display the first cut-out image 151 not including the unexposed area image and the erased whole image 200, the notification information 162 is also displayed together. You may make it display on part 3. At this time, the second cropped image may be displayed instead of the erased whole image 200 . Similarly, when the display control unit 82 causes the display unit 3 to simultaneously and separately display the whole image at the time of emission and the whole image at the time of erasure 200, which do not include the unexposed area image, the notification information 162 is also displayed on the display unit. 3 may be displayed. At this time, the second cropped image may be displayed instead of the erased whole image 200 .

As described above, the detector 40 according to this example can detect not only the emitted light L2 from the imaging plate 10 but also the reflected light of the excitation light L1 from the imaging plate 10 to some extent. Therefore, the reader 1 can obtain a radiation image based on detection of the emitted light L2 and a reflected light image (for example, an unexposed area image) based on detection of reflected light. Therefore, the convenience of the reading device 1 is improved.

For example, the reader 1 reads the above-described whole image at the time of emission including a radiographic image based on detection of the emitted light L2 from the imaging plate 10 and a reflected light image based on detection of the reflected light from the imaging plate 10. , the IP size can be appropriately specified, and the IP tilt angle can be specified appropriately.

Further, for example, as shown in FIGS. By simultaneously and separately displaying the reflected light image based on the detection of , the user can easily compare the radiation image read from the imaging plate 10 and the appearance of the imaging plate 10 . Thereby, the user can easily specify, for example, that the imaging plate 10 includes an unexposed portion.

In the above example, the object irradiated with the excitation light L1 was the imaging plate 10, but it may be other than the imaging plate 10. FIG. The object irradiated with the excitation light L1 may be, for example, an evaluation member having on its surface an evaluation pattern for image quality evaluation of a radiation image read from the imaging plate 10 by the reader 1 .

The member for evaluation has, for example, the same size and shape as the imaging plate 10 and is inserted into the reader 1 through the insertion port 2a of the reader 1 . The evaluation member placed in the reading device 1 is held by the holding section 20 in the same manner as the imaging plate 10 . The radiation image forming layer 11 was not formed on the member for evaluation. Therefore, even if the evaluation member is irradiated with the excitation light L1, the evaluation member does not emit the emission light L2.

When the holding unit 20 holds the evaluation member, the above-described irradiation object 1200 is composed of the holding unit 20 and the evaluation member held by the holding unit 20 . Hereinafter, the region where the evaluation member exists on the support-side main surface 1200a of the irradiation object 1200 is called an evaluation member existence region. On the supporting side main surface 1200a, a region outside the evaluation member existing region and inside the excitation light irradiation range R120 and the detection range R110 is called an evaluation member outer region or simply an outer region. The evaluation member existence region corresponds to the IP existence region R100, and the evaluation member outer region (in other words, the outer region) corresponds to the IP outer region R130.

54 to 57 are schematic diagrams showing an example of the evaluation member 900. FIG. FIG. 54 shows an evaluation member 900 (also referred to as resolution evaluation member 900A) for evaluating the resolution of detected radiation images. FIG. 55 shows an evaluation member 900 (also referred to as a geometric accuracy evaluation member 900B) for evaluating the geometric accuracy of a detected radiation image. FIG. 56 shows an evaluation member 900 (also referred to as a contrast evaluation member 900C) for evaluating the contrast of detected radiation images. FIG. 57 shows an evaluation member 900 (also referred to as an artifact evaluation member 900D) for evaluating artifacts in detected radiation images.

As shown in FIG. 54, a resolution evaluation pattern 902a for evaluating the resolution of the detected radiation image is shown on the front surface 901a of the resolution evaluation member 900A. A line pair chart, for example, is employed as the resolution evaluation pattern 902a.

As shown in FIG. 55, a geometric accuracy evaluation pattern 902b for evaluating the geometric accuracy of the detected radiation image is shown on the front surface 901b of the geometric accuracy evaluation member 900B. As the geometric accuracy evaluation pattern 902b, for example, a pattern in which a plurality of small dots are arranged in a lattice is adopted.

As shown in FIG. 56, a contrast evaluation pattern 902c for evaluating the contrast of the detected radiation image is shown on the front surface 901c of the contrast evaluation member 900C. As the contrast evaluation pattern 902c, for example, a pattern in which a plurality of square patterns expressed in grayscale and having different brightness (in other words, shading) are arranged is adopted.

As shown in FIG. 57, the front surface 901d of the artifact evaluation member 900D shows an artifact evaluation pattern 902d for evaluating the artifact of the detected radiation image. As the artifact evaluation pattern 902d, for example, a monochromatic uniform pattern is employed. For example, a pure white pattern may be employed as the artifact evaluation pattern 902d.

In the reading device 1 , the evaluation member 900 is held by the holding section 20 so that the evaluation pattern faces the light source 30 side. In other words, the evaluation member 900 is held by the holding section 20 so that its front surface faces the light source 30 side. Thus, the evaluation pattern of the evaluation member 900 is irradiated with the excitation light L1. Then, the detector 40 detects the reflected light of the excitation light L1 from the front surface of the evaluation member 900 and the outer region of the evaluation member, and outputs an image signal as the detection result.

Hereinafter, an image signal obtained as a detection result of reflected light when the evaluation member 900 is held by the holding unit 20 will be referred to as an evaluation image signal. A whole image based on the evaluation image signal is called an evaluation whole image. The whole evaluation image shows the evaluation pattern, and includes a reflected light image of the evaluation pattern (hereinafter also referred to as an evaluation pattern image). The evaluation global view does not include radiographic images. The whole image for evaluation consists only of reflected light images.

FIG. 58 is a flow chart showing an example of the operation of the reading device 1 when the reading device 1 acquires the evaluation whole image including the evaluation pattern. When the evaluation member 900 inserted from the insertion opening 2a of the housing 2 is held by the holding section 20 and the operation section 4 receives a predetermined operation from the user, step s51 is executed as shown in FIG. be. At step s<b>51 , the driving section 50 moves the holding section 20 to the reading start position under the control of the drive control section 83 . After step s51, step s52 is executed.

In step s52, the light source 30 irradiates the front surface and outer region of the evaluation member 900 with the excitation light L1. Then, the detector 40 detects the reflected light of the excitation light L1 at the front surface and outer region of the evaluation member 900, and outputs an evaluation image signal as the detection result. The evaluation image signal is a grayscale image signal.

After step s52, in step s53, the driving section 50 moves the holding section 20 to the discharge position under the control of the drive control section 83. FIG. Next, in step s54, the evaluation member 900 is discharged to the outlet 2b of the housing 2. FIG. Then, in step s55, the display control unit 82 causes the display unit 3 to display, for example, a grayscale image for evaluation based on the image signal for evaluation. When the resolution evaluation member 900A is put into the reading device 1, in step s55, an evaluation whole image including the image of the resolution evaluation pattern 902a is displayed. When the geometrical accuracy evaluation member 900B is inserted into the reading device 1, in step s55, an overall evaluation image including the image of the geometrical accuracy evaluation pattern 902b is displayed. When the contrast evaluation member 900C is placed in the reading device 1, in step s55, an entire evaluation image including the image of the contrast evaluation pattern 902c is displayed. When the artifact evaluation member 900D is placed in the reader 1, in step s55, an overall evaluation image including the image of the artifact evaluation pattern 902d is displayed. Note that step s55 may be executed at any time after step s52.

FIG. 59 is a schematic diagram showing an example of an overall evaluation image including an image of the resolution evaluation pattern 902a. FIG. 60 is a schematic diagram showing an example of an overall evaluation image including an image of the geometric accuracy evaluation pattern 902b. FIG. 61 is a schematic diagram showing an example of an overall evaluation image including an image of the contrast evaluation pattern 902c. FIG. 62 is a schematic diagram showing an example of an overall evaluation image including an image of the artifact evaluation pattern 902d. In step s55, the display unit 3 displays the overall image for evaluation in gray scales as shown in FIGS. 59 to 62, for example.

The user can evaluate the image quality of the detected radiation image based on the evaluation pattern image included in the overall evaluation image displayed on the display unit 3 . That is, the user can evaluate the image quality of the detected radiation image based on the evaluation pattern image displayed on the display unit 3 . For example, the user evaluates the resolution of the detected radiation image based on the image of the resolution evaluation pattern 902a displayed on the display unit 3. FIG. Further, the user evaluates the geometric accuracy of the detected radiation image based on the image of the geometric accuracy evaluation pattern 902b displayed on the display unit 3. FIG. Also, the user evaluates the contrast of the detected radiation image based on the image of the contrast evaluation pattern 902 c displayed on the display unit 3 . Further, the user evaluates artifacts in the detected radiation image based on the image of the artifact evaluation pattern 902 d displayed on the display unit 3 .

Thus, in this example, the light source 30 and the detector 40 for obtaining the detection radiation image are used, and the image signal for evaluation as a detection result of the reflected light of the excitation light L1 from the front surface of the member for evaluation 900 is obtained. have been obtained. Therefore, the image quality of the detected radiation image can be appropriately evaluated based on the evaluation pattern image included in the reflected light image based on the evaluation image signal. Therefore, the image quality of the detected radiation image can be properly evaluated without using an expensive evaluation phantom for recording the image of the evaluation pattern on the radiation image forming layer 11 of the imaging plate 10 .

The evaluation member 900 may be made of paper, resin, or metal, for example. Also, the evaluation pattern may be formed by being printed on the front surface of the evaluation member 900 . Also, at least one of the resolution evaluation pattern 902 a and the geometric accuracy evaluation pattern 902 b may be configured with unevenness on the front surface of the evaluation member 900 . When the evaluation pattern is printed on the front surface of the evaluation member 900, a highly accurate evaluation pattern can be obtained by printing technology. Therefore, image quality evaluation of the detected radiation image can be performed more appropriately. Also, the evaluation member 900 may be made of printed paper on which an evaluation pattern is printed. In this case, the image quality of the detected radiation image can be evaluated using the inexpensive evaluation member 900 . The evaluation member 900 may be constructed of cardboard.

According to this embodiment, the light source 30 irradiates the imaging plate 10 with the excitation light L1. The detector 40 functions as a first detector that detects the emitted light L2 from the imaging plate 10 due to the excitation light L1 and outputs a first image signal as the detection result of the emitted light L2. The light source 30 irradiates the evaluation member 900 having an evaluation pattern for image quality evaluation of the detected radiation image based on the first image signal on its surface with the excitation light L1. The detector 40 functions as a second detector that detects reflected light of the excitation light L1 from the surface of the evaluation member 900 and outputs a second image signal as a result of detection of the reflected light.

In this embodiment, the detector 40 is configured to serve as both the first detector and the second detector. A first detector may detect emitted light and a second detector may detect reflected light.

<Another configuration example of the reader>
Although the holding part 20 is moved in the above example, the holding part 20 does not have to be moved. In this case, by moving the light source 30, the detector 40, and the erasing light source 70 while the holding unit 20 is stopped, the reader 1 realizes the same processing as described above. Further, the light source 30, the detector 40, the erasing light source 70, and the holding section 20 may move.

Moreover, the reading device 1 may include a plurality of light sources. FIG. 63 is a schematic diagram showing a configuration example of a reading device 1 (also referred to as reading device 1A) provided with two light sources.

As shown in FIG. 63, the reading device 1A includes the light source 30 described above and a light source 130 separate therefrom. The light source 130 can irradiate the imaging plate 10 or the evaluation member 900 held by the holding section 20 with the irradiation light L11. The light source 130 has, for example, the same configuration as the light source 30, and can scan the irradiation light L11 in the main scanning direction DRm. The irradiation light L11 is, for example, visible laser light. The wavelength of the irradiation light L11 may be the same as or different from the wavelength of the excitation light L1. Light source 130 is controlled by light emission controller 86 in the same manner as light source 30 .

Light source 130 may be used, for example, in step s22 of FIG. 24 above. In this case, in step s22, the light source 130, not the light source 30, irradiates the front surface and the IP outer region of the erased imaging plate 10 with the illumination light L11. In step s22, similarly to the light source 30, the light source 130 repeats the process of scanning the imaging plate 10 and the IP outer region with the irradiation light L11 in the main scanning direction DRm under the control of the light emission control unit 86. On the other hand, in step s22, the driving section 50 moves the holding section 20 holding the imaging plate 10 in the sub-scanning direction DRs, as in the reading process described above. While the holding unit 20 is moving in the sub-scanning direction DRs, the process of scanning the irradiation light L11 in the main scanning direction DRm is repeatedly executed, so that the irradiation light L11 reaches the imaging plate 10 in the same manner as the excitation light L1. and IP outer regions. In step s22, while the imaging plate 10 is being raster-scanned with the irradiation light L11, the detector 40 detects the reflected light of the irradiation light L11 from the imaging plate 10, and outputs the erasing image signal as the detection result. Output. The erasing overall image based on the erasing image signal includes the IP reflected light image and the IP outer region image, and does not include the radiation image, similar to the above-described erasing overall image based on the detection of the reflected light of the excitation light L1. . At step s27 in FIG. 24, the entire image at the time of erasing is displayed based on the detection of the reflected light of the irradiation light L11. The reading device 1A can use the erasing overall image based on the detection of the reflected light of the irradiation light L11 as well as the erasing overall image based on the detection of the reflected light of the excitation light L1. For example, the reading device 1A may specify the IP tilt angle or the IP size based on the erasing overall image based on the detection of the reflected light of the irradiation light L11.

Light source 130 may also be used, for example, in step s52 of FIG. 58 above. In this case, in the reading device 1A, the light source 130, not the light source 30, irradiates the front surface and the outer region of the evaluation member 900 with the irradiation light L11 in step s52. The operation of the reading device 1A in step s52 is the same as the operation of the reading device 1A in step s22 described above. In step s52, while the evaluation member 900 and the outer region are being raster-scanned with the irradiation light L11, the detector 40 detects the reflected light of the irradiation light L11 from the evaluation member 900 and the outer region. An evaluation image signal is output as a result. The overall evaluation image based on this evaluation image signal includes the evaluation pattern image and does not include the radiation image, like the above-described evaluation overall image based on the detection of the reflected light of the excitation light L1. At step s55 in FIG. 58, the evaluation whole image based on the detection of the reflected light of the irradiation light L11 is displayed on the display unit 3 based on the evaluation image signal obtained at step s52. The user can evaluate the image quality of the detected radiation image based on the evaluation pattern image included in the overall evaluation image displayed on the display unit 3 of the reading device 1A.

The reader 1 may comprise multiple detectors. FIG. 64 is a schematic diagram showing a configuration example of a reading device 1 (also referred to as reading device 1B) having two detectors and one light source.

As shown in FIG. 64, the reader 1B includes the detector 40 described above and a detector 140 different from the detector 40 . Further, the reading device 1B has the light source 30 and does not have the light source 130 . Detector 140 has, for example, the same configuration as detector 40 . Detector 140 can detect emitted light L2 from imaging plate 10 in the same manner as detector 40 . Further, the detector 140, like the detector 40, the reflected light of the excitation light L1 from the imaging plate 10 or the evaluation member 900, and the reflected light of the excitation light L1 from the IP outer region or the evaluation member outer region can be detected.

Detector 140 may, for example, be used in step s22 of FIG. 24 above. In this case, in the reader 1B, in step s22, while the light source 30 is raster scanning over the front surface and the IP outer region of the erased imaging plate 10, the detector 140 scans from the imaging plate 10 and the IP outer region. The reflected light of the excitation light L1 is detected, and an erasing image signal is output as the detection result. The erased whole image based on the erased image signal includes the IP reflected light image and the IP outer region image, but does not contain the radiation image, like the erased whole image described so far. The reading device 1B can perform various processes such as identification of the IP tilt angle based on the erased whole image acquired in step s22.

Detector 140 may also be used, for example, in step s52 of FIG. 72 above. In this case, in the reader 1B, in step s52, while the light source 30 is raster scanning with respect to the front and outer regions of the evaluation member 900, the detector 140 detects excitation from the evaluation member 900 and the outer region. The reflected light of the light L1 is detected, and an evaluation image signal is output as the detection result. The overall evaluation image based on this evaluation image signal includes the evaluation pattern image and does not include the radiation image, like the evaluation overall image described above.

The reader 1 may comprise multiple detectors and multiple light sources. FIG. 65 is a schematic diagram showing a configuration example of a reading device 1 (also referred to as reading device 1C) including detectors 40 and 140 and light sources 30 and 130. As shown in FIG.

The reader 1C may use the detector 140 and the light source 130, for example, in step s22 of FIG. 24 described above. In this case, in the reader 1C, in step s22, while the light source 130 is raster scanning over the front surface and IP outer region of the erased imaging plate 10, the detector 140 scans from the imaging plate 10 and the IP outer region. The reflected light of the excitation light L1 is detected, and an erasing image signal is output as the detection result. The erased whole image based on the erased image signal includes the IP reflected light image and the IP outer region image, but does not contain the radiation image, like the erased whole image described so far.

Also, the reading device 1C may use the detector 140 and the light source 130, for example, in step s52 of FIG. 72 described above. In this case, in the reader 1C, in step s52, while the light source 130 is raster-scanning the front and outer regions of the evaluation member 900, the detector 140 detects excitation from the evaluation member 900 and the outer region. The reflected light of the light L1 is detected, and an evaluation image signal is output as the detection result. The overall evaluation image based on this evaluation image signal includes the evaluation pattern image and does not include the radiation image, like the evaluation overall image described above.

In the readers 1A and 1C, the light source 130 may output light other than visible light as the irradiation light L11. For example, the irradiation light L11 may be infrared rays or ultraviolet rays. In this case, a detector capable of detecting infrared rays or ultraviolet rays is employed as the detector 40 and the detector 140 .

Moreover, in the reading devices 1B and 1C, the detector 140 that detects the reflected light of the irradiation light L11 may include, for example, a CCD sensor or a CMOS sensor used in cameras. CCD is an abbreviation for Charge Coupled Device, and CMOS is an abbreviation for Complementary Metal Oxide Semiconductor.

Further, in the reading device 1C, the light source 130 does not scan the irradiation light L11, but like the erasing light source 70, irradiates the entire range of the imaging plate 10 or the evaluation member 900 with the irradiation light L11 in one irradiation. You can irradiate. In this case, detector 140 may comprise, for example, a CCD sensor or a CMOS sensor used in cameras.

Further, in the readers 1B and 1C, the detector 40 may not be able to detect the reflected light of the excitation light L1. In this case, the optical filter 42 of the detector 40 does not have to transmit the excitation light L1. Further, in the reading device 1C, the detector 40 may not be able to detect the reflected light of the irradiation light L11. In this case, the optical filter 42 of the detector 40 does not have to transmit the irradiation light L11.

In the whole image during light emission acquired when the detector 40 does not detect the reflected light of the excitation light L1, when the imaging plate 10 includes an unexposed portion, the luminance value of the unexposed area image and the IP outer area image It becomes a value similar to the brightness value. Therefore, when the imaging plate 10 includes an unexposed portion, the image processing unit 81, in the method using the binarized image as described above, specifies the IP tilt angle and the IP size based on the entire image during light emission. becomes difficult. However, even if the imaging plate 10 includes an unexposed portion, the image processing unit 81 calculates the IP tilt angle and the IP size based on the erased whole image based on the erased image signal output by the detector 140. can be adequately identified as described above.

Further, in the readers 1B and 1C, the detector 140 does not have to be able to detect the emitted light L2. In this case, the readers 1B and 1C can obtain the IP reflected light image without erasing the radiation image from the imaging plate 10. FIG. For example, the reading device 1B may simultaneously operate the detectors 40 and 140 in the reading process of step s2 described above. In this case, the detection of the emitted light L2 by the detector 40 and the detection of the reflected light of the excitation light L1 from the imaging plate 10 by the detector 14 are performed in parallel. The overall image based on the image signal output by the detector 140 is the same image as the erasing overall image, and includes the IP reflected light image and the IP outer area image, but does not include the radiation image. Further, the reading device 1C may simultaneously operate the light sources 30 and 130 and simultaneously operate the detectors 40 and 140 in the reading process of step s2 described above. In this case, the detection of the emitted light L2 by the detector 40 and the detection of the reflected light of the irradiation light L11 from the imaging plate 10 by the detector 140 are performed in parallel. Also in this case, the overall image based on the image signal output by the detector 140 is the same image as the erasing overall image, and includes the IP reflected light image and the IP outer region image, but does not include the radiation image. In this manner, in the reading process, not only the radiation image based on the detection of the emitted light L2 but also the reflected light image based on the detection of the reflected light of the excitation light L1 or the irradiation light L11 is obtained. and the processing of s22 becomes unnecessary. That is, in the series of processes shown in FIG. 14 described above, it is possible to obtain a radiographic image based on the detection of the emitted light L2 and a reflected light image based on the detection of the reflected light of the excitation light L1 or the irradiation light L11. Therefore, the operation of the reading device 1 can be simplified.

In the reading device 1 of the above example, a plurality of components other than the AC adapter 5 are integrated in the housing 2, but they do not have to be integrated. For example, the reading device 1 may include a display section 13 positioned outside the housing 2 separately from the display section 3 provided in the housing 2 or instead of the display section 3 . FIG. 66 is a schematic diagram showing an example of a configuration of a reading device 1 (also referred to as a reading device 1D) having a display section 13 outside the display surface of the housing 2. As shown in FIG. The display unit 13 can also be called the display device 13 .

The display unit 13 is, for example, a liquid crystal display device or an organic EL display device, and is capable of displaying various information such as characters, symbols, graphics, and images. The display unit 13 is controlled by a display control unit 82 of a control unit 80 inside the housing 2 . The display control unit 82 can control the display unit 13 through the interface unit 95 inside the housing 2, for example. Communication between the interface unit 95 and the display unit 13 may conform to USB, DisplayPort, or HDMI (High-Definition Multimedia Interface) (registered trademark). . Further, the interface unit 95 may be wired or wirelessly connected to the display unit 13 . The display unit 13 may display an acquired whole image or may display a clipped image. In addition, in the example of FIG. 76, the display unit 3 is provided in the housing 2 of the reading device 1D, but the display unit 3 may not be provided. Further, the reading device 1D may include a plurality of light sources or a plurality of detectors, as shown in FIGS. 63-65.

67 and 68 are schematic diagrams showing another example of the configuration of the reading device 1. FIG. In the reader 1 (also referred to as reader 1E) shown in FIGS. 67 and 68, a computer device 950 having part of the functions of the reader 1E is provided outside the housing 2 . As shown in FIG. 68, the computer device 950 includes, for example, the display section 3, the image processing section 81, and the display control section 82 described above. Computing device 950 may be, for example, a personal computer (also called a general purpose computer). In this case, the computer device 950 may be of a notebook type or a desktop type. Hereinafter, in the reading device 1E, the housing 2, a plurality of components integrated by the housing 2, and the AC adapter 5 may be collectively referred to as a reading device main body 9. FIG.

The computer device 950 can communicate with the reader main body 9 . The computer device 950 includes, for example, a control section 951 having an image processing section 81 and a display control section 82 and an interface section 952 communicating with the reading device main body 9 . The computer device 950 also includes an operation unit 953 that receives operations from the user.

The control unit 951 can integrally manage the operation of the computer device 950, and can be called a control circuit. The control unit 951 can control the display unit 3 and the interface unit 952, for example. Further, the control unit 951 can perform processing according to user operations received by the operation unit 953 .

The control unit 951 can be said to be a kind of computer device including, for example, at least one processor and a storage unit. At least one processor included in the control unit 951 may include a CPU, or may include a processor other than the CPU. In the control portion 951, various functions are realized by at least one processor executing a program in a storage portion (also referred to as a storage circuit). In the control unit 951, the image processing unit 81 and the display control unit 82 described above are formed as functional blocks by at least one processor executing a program in the storage unit.

The operation unit 953 has, for example, a keyboard and a mouse. The operation unit 953 may include a touch sensor that detects a user's touch operation. When the operation unit 953 includes a touch sensor, the touch sensor and the display unit 3 may constitute a touch panel display having a display function and a touch detection function.

The interface section 952 can communicate with the interface section 95 of the reader body 9 . Communication between the interface unit 952 and the interface unit 95 of the reader body 9 may conform to Ethernet, USB, WiFi, or other standards. May comply. The interface unit 952 may perform wired communication with the interface unit 95, or may perform wireless communication. The interface unit 952 can be called an interface circuit, a communication unit, or a communication circuit. The control section 951 of the computer device 950 and the control section 80 of the reading device main body 9 can exchange information with each other through the interface section 952 and the interface section 95 .

In the reader 1E, the control section 951 of the computer device 950 and the control section 80 of the reading device main body 9 work together to execute the above-described various processes that were performed by the control section 80 . In the reading device 1</b>E, the detection control section 85 outputs the image signal output by the detector 40 to the interface section 95 . The interface section 95 outputs the input image signal to the interface section 952 . The interface unit 952 inputs the input image signal to the control unit 951 . The image processing unit 81 performs the image processing described above on the image signal input to the control unit 951 . Then, the image processing unit 81 executes the above-described tilt angle specifying process, size specifying process, and clipping process based on the image signal after the image processing. Further, the display control unit 82 causes the display unit 3 to display, for example, an acquired overall image based on the image signal after image processing.

The operation unit 953 of the computer device 950 may receive at least some of the user operations received by the operation unit 4 of the reader main body 9 . For example, the operation unit 953 may accept a user operation instructing the start of the series of processes in FIG. 14, may accept a user operation instructing the start of the series of processes in FIG. A user operation instructing the start of a series of processes may be accepted, or a user operation instructing the start of the series of processes in FIG. 58 may be accepted. In this case, the control unit 951 notifies the reader main body 9 of the user operation received by the operation unit 953 through the interface unit 952 . In the reading device main body 9 , the control unit 80 receives the notification from the control unit 951 through the interface unit 95 and executes processing according to the user's operation received by the operation unit 953 .

Further, the operation unit 953 may accept user operations that the operation unit 4 does not accept, and the operation unit 4 may accept user operations that the operation unit 953 does not accept. Further, when the user operation received by the operation unit 953 conflicts with the user operation received by the operation unit 4, in the reading device 1E, for example, processing according to the user operation received by the reading device main body 9 is preferentially executed. may be

Note that the reading device 1E may include a display section provided in the housing 2, as shown in FIG. 1 and the like described above. Further, the reading device 1E may be provided with a plurality of light sources or a plurality of detectors, as shown in FIGS. 63-65. Further, the reading device 1E does not have to include either one of the operation units 4 and 953 . Further, in the reading device 1E, the control section 80 of the reading device main body 9 may instead execute some of the processes performed by the image processing section 81 of the computer device 950 . For example, the control unit 80 may perform image processing on the image signal from the detector 40 and the image signal after image processing may be input to the image processing unit 81 .

Although the reader 1 has been described in detail as above, the above description is illustrative in all aspects, and the present disclosure is not limited thereto. Moreover, the various modifications described above can be applied in combination as long as they do not contradict each other. And it is understood that numerous variations not illustrated can be envisioned without departing from the scope of this disclosure.

1, 1A, 1B, 1C, 1D, 1E Reader 10 Imaging plate 30, 130 Light source 40, 140 Detector 81 Image processing unit 900, 900A, 900B, 900C, 900D Evaluation members 902a, 902b, 902c, 902d For evaluation Pattern L1 Excitation light L2 Emission light L11 Irradiation light

Claims (5)

A reading device for reading a radiographic image from an imaging plate,
a light source that irradiates the imaging plate with excitation light;
A first detector that detects emitted light from the imaging plate due to the excitation light and outputs a first image signal as a detection result of the emitted light,
The light source irradiates the excitation light to an evaluation member having an evaluation pattern for image quality evaluation of the detected radiation image based on the first image signal on its surface,
The reading device further comprises a second detector that detects the reflected light of the excitation light from the surface of the evaluation member and outputs a second image signal as a detection result of the reflected light. The reader according to claim 1, wherein
the first detector functions as the second detector;
The reading device, wherein the first detector detects the emitted light and the reflected light. The reader according to claim 1 or claim 2,
The reading device, wherein the evaluation pattern is printed on the surface of the evaluation member. A reader according to claim 3, wherein
The reading device, wherein the member for evaluation is printed paper. The reader according to any one of claims 1 to 4,
A reader that displays a reflected light image based on the second image signal.

Images