Reading device

Abstract

To improve convenience of a reading device which reads a radiological image from an imaging plate.SOLUTION: The reading device which reads a radiological image from an imaging plate comprises: a support face which supports the imaging plate and more hardly reflects light than the imaging plate; a light source which irradiates the imaging plate and the support face with excitation light; and a detector which detects stimulable light coming from the imaging plate by the excitation light and reflected light of the excitation light coming from the imaging plate and the support face.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a reading device. [Background technology]

[0002] Patent Document 1 describes a technique for reading image information from a storage phosphor sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-267451 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to improve the convenience of a reader that reads a radiation image from an imaging plate.

[0005] Therefore, an object of the present disclosure is to provide a technique capable of improving the convenience of a reading device that reads a radiation image from an imaging plate. [Means for solving the problem]

[0006] In one embodiment, a reading device for reading a radiation image from an imaging plate includes a support surface for supporting the imaging plate and reflecting light less easily than the imaging plate, a light source for irradiating the imaging plate and the support surface with excitation light, and a detector for detecting photostimulated luminescence from the imaging plate due to the excitation light and reflected light of the excitation light from the imaging plate and the support surface. Effect of the Invention

[0007] The convenience of the reading device is improved. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a schematic diagram showing an example of the appearance of a reading device. [Diagram 2] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Diagram 3] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 4] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Diagram 5] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 6] FIG. 2 is a block diagram showing an example of a configuration of a reading device. [Figure 7] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 8] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 9] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 10] 3 is a schematic diagram showing an example of an IP image region, an excitation light irradiation range, and a detection range. FIG. [Figure 11] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 12] 3 is a schematic diagram showing an example of an IP image region, an excitation light irradiation range, and a detection range. FIG. [Figure 13] 3 is a schematic diagram showing an example of an IP image region, an excitation light irradiation range, and a detection range. FIG. [Figure 14] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 15] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 16] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 17] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 18] 10 is a flowchart showing an example of the operation of the reading device. [Figure 19] 10A and 10B are schematic diagrams showing an example of how an imaging plate is tilted. [Figure 20] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 21]10A and 10B are schematic diagrams for explaining an example of a tilt angle identification process. [Figure 22] 10A and 10B are schematic diagrams for explaining an example of a tilt angle identification process. [Figure 23] FIG. 11 is a schematic diagram for explaining an example of a size specification process. [Figure 24] FIG. 4 is a diagram showing an example of different sizes of imaging plates. [Diagram 25] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 26] 10 is a flowchart showing an example of the operation of the reading device. [Figure 27] 10 is a flowchart showing an example of the operation of the reading device. [Figure 28] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 29] FIG. 13 is a schematic diagram showing a display example of an acquired overall image. [Diagram 30] FIG. 13 is a schematic diagram showing a display example of an acquired overall image. [Diagram 31] FIG. 11 is a schematic diagram for explaining an example of a tilt correction process. [Diagram 32] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Diagram 33] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Diagram 34] FIG. 13 is a schematic diagram showing an example of an extracted image. [Diagram 35] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Diagram 36] FIG. 13 is a schematic diagram showing an example of an extracted image. [Figure 37] 11 is a schematic diagram showing a display example of an extracted image. FIG. [Figure 38] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Figure 39] FIG. 13 is a schematic diagram showing an example of an extracted image. [Diagram 40] FIG. 13 is a schematic diagram showing an example of an extracted image. [Diagram 41] FIG. 4 is a schematic diagram showing an example of a configuration of a holding portion. [Diagram 42]FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Diagram 43] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Diagram 44] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Diagram 45] FIG. 13 is a schematic diagram showing an example of an extracted image. [Diagram 46] FIG. 1 is a schematic diagram showing an example of an acquired overall image. [Figure 47] FIG. 11 is a schematic diagram for explaining an example of a cutout process. [Figure 48] FIG. 13 is a schematic diagram showing an example of an extracted image. [Figure 49] FIG. 13 is a schematic diagram showing an example of an extracted image. [Figure 50] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Figure 51] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Figure 52] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Diagram 53] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Figure 54] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Figure 55] 13 is a schematic diagram showing an example of a display of unexposed notification information. FIG. [Figure 56] FIG. 2 is a schematic diagram showing an example of a radiation image included in an acquired overall image. [Figure 57] FIG. 1 is a schematic diagram showing an example of an IP total reflected light image included in an acquired total image. [Figure 58] 11 is a schematic diagram showing a display example of an extracted image. FIG. [Figure 59] 11 is a schematic diagram showing a display example of an extracted image. FIG. [Figure 60] FIG. 1 is a schematic diagram showing an example of an IP total reflected light image included in an acquired total image. [Figure 61] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 62] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 63]FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 64] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 65] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 66] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 67] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 68] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 69] FIG. 2 is a schematic diagram illustrating an example of an imaging plate. [Figure 70] FIG. 2 is a schematic diagram illustrating an example of an evaluation member. [Figure 71] FIG. 2 is a schematic diagram illustrating an example of an evaluation member. [Figure 72] FIG. 2 is a schematic diagram illustrating an example of an evaluation member. [Figure 73] FIG. 2 is a schematic diagram illustrating an example of an evaluation member. [Figure 74] 10 is a flowchart showing an example of the operation of the reading device. [Figure 75] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 76] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 77] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 78] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 79] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. [Figure 80] FIG. 2 is a schematic diagram showing an example of the configuration of a reading device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1 is a schematic diagram showing an example of the appearance of a reading device 1. The reading device 1 is a device that reads a radiation image from an imaging plate 10 on which the radiation image is recorded. The reading device 1 can also be said to be a device that detects the radiation image recorded on the imaging plate 10.

[0010] The imaging plate 10 has a flat shape and a radiation image forming layer 11, and is a recording medium for recording a radiation image. The imaging plate 10 has, for example, a generally rectangular flat shape with rounded corners. The radiation image forming layer 11 is a layer that accumulates the energy of irradiated radiation and emits photostimulable light according to the accumulated energy. For example, the radiation image forming layer 11 is formed by coating one main surface of a film made of resin with a photostimulable phosphor. X-rays, for example, are used as the radiation irradiated to the radiation image forming layer 11. When X-rays from an X-ray generator penetrate the object to be photographed and irradiate the imaging plate 10, energy according to the intensity of the X-rays is accumulated in the radiation image forming layer 11. Since the intensity of the X-rays is based on the distribution of X-ray absorbing regions in the object to be photographed, the distribution of the energy accumulated in the radiation image forming layer 11 is a radiation image of the object to be photographed by X-rays. In this way, the imaging plate 10 records a radiation image by, for example, X-rays as a latent image. The reader 1 reads the radiation image from the radiation image forming layer 11 and generates an image signal (also called image data) representing the read radiation image.

[0011] In this example, the imaging plate 10 is irradiated with radiation while being placed in, for example, a person's mouth. Therefore, the imaging plate 10 is sized to fit inside a person's mouth. A radiation image of, for example, teeth is recorded on the radiation image forming layer 11 of the imaging plate 10. However, the use of the imaging plate 10 is not limited to this.

[0012] Hereinafter, the main surface of the imaging plate 10 facing the radiation image forming layer 11 may be referred to as the front surface, and the main surface of the imaging plate 10 opposite the front surface may be referred to as the back surface.

[0013] 1, the reading device 1 includes, for example, a housing 2. The housing 2 contains a configuration for reading a radiation image from an imaging plate 10. This configuration will be described later.

[0014] The housing 2 is provided with an insertion opening 2a and an ejection opening 2b. The insertion opening 2a is provided, for example, on the top surface of the housing 2. A user of the reading device 1 can insert an imaging plate 10 into the housing 2 through the insertion opening 2a. A radiation image of the imaging plate 10 is read inside the housing 2. The ejection opening 2b is provided, for example, on a lower portion of one side surface of the housing 2. The imaging plate 10 after the radiation image has been read (also referred to as the read imaging plate 10) is ejected through the ejection opening 2b. A user of the reading device 1 can collect the read imaging plate 10 through the ejection opening 2b.

[0015] In this example, the reader 1 can erase the radiation image from the imaging plate 10 after reading out the radiation image from the imaging plate 10. For example, the imaging plate 10 from which the radiation image has been erased is discharged from the outlet 2b.

[0016] The housing 2 is provided with, for example, an operation unit 4 that accepts operations from a 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 touch operation by the user.

[0017] The housing 2 is provided with, for example, a display unit 3. The display unit 3 is configured with, for example, a liquid crystal display panel or an organic EL (electro-luminescence) display panel. The display unit 3 is capable of displaying various types of information, for example, characters, symbols, figures, and images. The display unit 3 may display a radiation image read from the imaging plate 10 (in other words, a detected radiation image).

[0018] When the operation unit 4 includes a touch sensor, the touch sensor and the display unit 3 may form a touch panel display having a display function and a touch detection function. In this case, at least one of the multiple operation buttons 4a may be replaced with a software button displayed on the touch panel display, and the operation unit 4 may not include the multiple operation buttons 4a. In addition, the reading device 1 may not include the display unit 3.

[0019] The housing 2 is provided with plate storage cases 6 and 7 capable of storing, for example, an imaging plate 10. The plate storage cases 6 and 7 are provided, for example, on the upper surface of the housing 2. The plate storage case 6 is a case with a partition, and the plate storage case 7 is a case with a lid. The reading device 1 does not necessarily have to include at least one of the plate storage cases 6 and 7.

[0020] A cable 5a of an AC adapter 5 extends outward from the housing 2. Power is supplied to each component of the reading device 1 from the AC adapter 5. The reading device 1 may include not only the AC adapter 5 but also a battery that supplies power to each component of the reading device 1. Alternatively, the reading device 1 may include a battery instead of the AC adapter 5.

[0021] <An example of the mechanism inside the housing> 2 to 5 are schematic diagrams showing an example of the configuration inside the housing 2. FIG. 3 is a schematic diagram showing an example of the cross-sectional structure along the arrow AA in FIG. 2. FIG. 5 is a schematic diagram showing an example of the cross-sectional structure along the arrow BB in FIG. 4. FIG. 6 is a block diagram mainly showing an example of the configuration of a control unit 80 provided in the reading device 1. As will be described later, the holding unit 20 that holds the imaging plate 10 is capable of moving along a predetermined direction DR10 within the housing 2. FIG. 4 shows the imaging plate 10 and the holding unit 20 having moved from the state shown in FIG. 2.

[0022] 2 to 6, the reading device 1 includes, for example, a holding unit 20, a light source 30, a detector 40, a driving unit 50, a pair of guide units 60, an erasing light source 70, a control unit 80, and an interface unit 95. These components are provided within a housing 2.

[0023] <About the control unit> The control unit 80 can comprehensively manage the operation of the reading device 1 and can also be called a control circuit. The control unit 80 can control, for example, 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. The control unit 80 can also perform processing in response to a user operation received by the operation unit 4.

[0024] The control unit 80 is configured by, for example, a computer device including at least one processor and a storage unit. The at least one processor included in the control unit 80 may include a CPU (Central Processing Unit) or a processor other than the CPU. In the control unit 80, the at least one processor executes a program in the storage unit (also called a storage circuit), thereby realizing various functions described below.

[0025] In the control unit 80, at least one processor executes a program in the memory unit to form functional blocks such as an image processing unit 81, a display control unit 82, a drive control unit 83, a retention control unit 84, a detection control unit 85, a light emission control unit 86, and an erasure control unit 87.

[0026] The image processing unit 81 can perform image processing on, for example, an image signal (described later) output from the detector 40. The display control unit 82 can control the display of the display unit 3. The drive control unit 83 can control the drive unit 50. The retention control unit 84 can control the retention unit 20. The detection control unit 85 can control the detector 40. The light emission control unit 86 can control the light source 30. The erasure control unit 87 can control the erasure light source 70.

[0027] Note that some of the functions of the control unit 80 or all of the functions of the control unit 80 may be realized by a hardware circuit that does not require software (in other words, a program) to realize the functions. For example, some of the functions of the image processing unit 81 or all of the functions of the image processing unit 81 may be realized by a hardware circuit that does not require software to realize the functions. The image processing unit 81 may be an image processing circuit independent of other configurations. Also, some of the functions of the display control unit 82 or all of the functions of the display control unit 82 may be realized by a hardware circuit that does not require software to realize the functions. The display control unit 82 may be a display control circuit independent of other configurations. Also, some of the functions of the drive control unit 83 or all of the functions of the drive control unit 83 may be realized by a hardware circuit that does not require software to realize the functions. The drive control unit 83 may be a drive control circuit independent of other configurations. Also, some of the functions of the retention control unit 84 or all of the functions of the retention control unit 84 may be realized by a hardware circuit that does not require software to realize the functions. The retention control unit 84 may be a retention control circuit independent of other configurations. Also, some of the functions of the detection control unit 85 or all of the functions of the detection control unit 85 may be realized by a hardware circuit that does not require software to realize the functions. The detection control unit 85 may be a detection control circuit independent of other components. Also, some functions of the light emission control unit 86 or all of the functions of the light emission control unit 86 may be realized by a hardware circuit that does not require software to realize the functions. The light emission control unit 86 may be a light emission control circuit independent of other components. Also, some functions of the erase control unit 87 or all of the functions of the erase control unit 87 may be realized by a hardware circuit that does not require software to realize the functions. The erase control unit 88 may be a erase control circuit independent of other components.

[0028] <Interface section> The interface unit 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 unit. The external device may include a personal computer, a mobile phone such as a smartphone, or other computer devices. The external device may also include a data recording medium (for example, a flash memory) that is detachable from the reading device 1. The interface unit 95 can receive a signal from the external device and input the received signal to the control unit 80. The interface unit 95 can also transmit a signal from the control unit 80 to the external device. For example, the interface unit 95 can transmit an image signal that has been image-processed in the image processing unit 81 of the control unit 80 to the external device. The interface unit 95 may perform wired communication with the external device, or may perform wireless communication. The communication between the interface unit 95 and the external device may be compliant with Ethernet, USB (Universal Serial Bus), WiFi, or other standards.

[0029] <About the holding part> The holding unit 20 holds the imaging plate 10 inserted through the insertion opening 2a of the housing 2. The holding unit 20 includes, for example, a support plate 21 that supports the imaging plate 10, and a fixing unit 22 that fixes the position of the imaging plate 10 supported by the support plate 21.

[0030] The support plate 21 has 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 fixing portion 22 has, for example, a plurality of fixing portions 22a that approach the peripheral portion of the imaging plate 10. The fixing portion 22 can also be called a fixing member. The plurality of fixing portions 22a approach the peripheral portion of the imaging plate 10 so as to surround the peripheral portion. This fixes the position (i.e., relative position) and attitude (i.e., relative attitude) of the imaging plate 10 with respect to the support plate 21. In this example, for example, two fixing portions 22a approach each of both long sides of the imaging plate 10, and one fixing portion 22a approaches each of both short sides of the imaging plate 10.

[0031] Each fixed portion 22a can be moved between a close position where it approaches the imaging plate 10 supported by the support plate 21 and a separated position where it is separated from the imaging plate 10 supported by the support plate 21 under the control of the holding control unit 84. With each fixed portion 22a in the separated position, the imaging plate 10 is inserted into the housing 2 through the insertion opening 2a and supported by the support plate 21. Thereafter, each fixed portion 22a moves from the separated position to the close position, whereby the position and attitude of the imaging plate 10 are fixed by the fixing portion 22. When each fixed portion 22a is in the close position, it is in contact with, for example, a peripheral portion of the imaging plate 10.

[0032] When at least one of the multiple fixing portions 22a is in the close position, it does not have to be in contact with the peripheral portion of the imaging plate 10. The configuration of the fixing portion 22 is not limited to the above. The configuration of the holding portion 20 is not limited to the above.

[0033] <About the drive unit and pair of guide units> The drive unit 50 is capable of moving the holder 20 along the predetermined direction DR10 under the control of the drive control unit 83. This allows the imaging plate 10 held by the holder 20 to also move along the predetermined direction DR10. It can also be said that the drive unit 50 is capable of moving the imaging plate 10 along the predetermined direction DR10 via the holder 20.

[0034] The pair of guide parts 60 extend along the predetermined direction DR10 with the holding part 20 sandwiched therebetween. A groove extending along the predetermined direction DR10 is formed on the inner side of each guide part 60. A pair of opposing side edges of the support plate 21 are fitted into the inner grooves of the pair of guide parts 60, respectively. This allows the pair of guide parts 60 to guide the movement of the holding part 20 along the predetermined direction DR10. However, the configuration of the guide parts 60 is not limited to this.

[0035] The driving unit 50 is configured, for example, by a ball screw mechanism having a motor 51, a screw shaft portion 52, and a nut portion 53. The motor 51 is controlled by a driving control unit 83. The screw shaft portion 52 is a rod-shaped member having a screw groove formed around its periphery. The screw shaft portion 52 extends along a predetermined direction DR10 and is rotated by the motor 51. The nut portion 53 is fixed to the holding unit 20. The nut portion 53 is fixed, for example, to the back surface 21b of the support plate 21 of the holding unit 20. The screw shaft portion 52 is screwed into the nut portion 53. The screw shaft portion 52 rotates in a forward direction or a reverse direction according to the rotation of the motor 51 in the forward direction or the reverse direction. The holding unit 20 moves to one side along the predetermined direction DR10 according to the rotation of the screw shaft portion 52 in the forward direction. At this time, the pair of guide portions 60 guide the movement of the holding unit 20 to one side. On the other hand, the holding portion 20 moves to the other side along the predetermined direction DR10 in response 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 driving portion 50 is not limited to this.

[0036] The drive unit 50 can move the holder 20 holding the imaging plate 10 to a reading start position where reading of the radiation image from the imaging plate 10 starts. Furthermore, when reading of the radiation image from the imaging plate 10 is completed, the drive unit 50 can move the holder 20 holding the imaging plate 10 to an erasing position where the radiation image on the imaging plate 10 is erased. Figures 2 and 3 show how the radiation image is read from the imaging plate 10. Figures 4 and 5 show how the radiation image is erased from the imaging plate 10.

[0037] <Light source and detector> 6, a light source 30, a light emission control unit 86 that controls the light source 30, a detector 40, and a detection control unit 85 that controls the detector 40 constitute a light measurement instrument 90 that reads a radiation image from the front surface of the imaging plate 10. The light source 30, detector 40, detection control unit 85, and light emission control unit 86 that constitute the light measurement instrument 90 may be housed in a single case and formed as a unit, or they may not be housed in a single case.

[0038] The light source 30 can irradiate the imaging plate 10 held by the holder 20 with excitation light L10 for exciting the radiation image forming layer 11. The target of irradiation with the excitation light L10 is, for example, the imaging plate 10 serving as a photoreceptor for radiography of a living body. The light source 30 emits the excitation light L10 toward the support surface 21a of the holder 20. The light source 30 can scan the imaging plate 10 with the excitation light L10 in one direction (also called the main scanning direction DRm). The main scanning direction DRm is a direction perpendicular to the predetermined direction DR10. In other words, the main scanning direction DRm is a direction perpendicular to the moving direction of the holder 20. The light source 30 can also irradiate the excitation light L10 not only to the imaging plate 10 but also to the surrounding area of ​​the imaging plate 10.

[0039] In this disclosure, light that acts on an object is called action light L1. And light that is generated by the action of action light L1 on an object is called acted-on light L2. Excitation light L10 is an example of action light L1. Light that does not have the exciting power to generate stimulated emission but generates reflected light on an object is another example of action light L1. Action light L1 can also be said to be light that is composed of at least one of excitation light and action light that is not excitation light. Acted-on light L2 is light that is emitted from an object as a result of the action of action light L1.

[0040] The excitation light L10 is, for example, a visible laser light. The excitation light L10 may be, for example, a red laser light or a laser light of another color. The detector 40 detects, for example, the acted light L2 from the imaging plate 10 generated by irradiation with the excitation light L10, which is the acted light L1, and outputs an electrical signal according to the intensity of the detected acted light L2. The detector 40 also detects the acted light L2 from outside the imaging plate 10 generated by irradiation with the excitation light L10, and outputs an electrical signal according to the intensity of the detected acted light L2.

[0041] The light source 30 includes, for example, a laser generating unit that generates and outputs the excitation light L10, and a scanning unit that scans the imaging plate 10 with the excitation light L10 in the main scanning direction DRm. The laser generating unit includes, for example, a semiconductor laser oscillator, and is controlled by the light emission control unit 86. The laser generating unit may include a laser diode or another semiconductor laser. The scanning unit includes, for example, a MEMS (Micro Electro Mechanical Systems) mirror that reflects the excitation light L10 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 L10 under the control of the light emission control unit 86 so that the irradiation point of the excitation light L10 on the radiation image forming layer 11 moves in the main scanning direction DRm. The scanning unit may include another mirror, such as a galvanometer mirror, instead of the MEMS mirror.

[0042] The detector 40 detects the acted light L2 from the position irradiated with the excitation light L10. The detector 40 includes, for example, an optical filter 42 into which the acted light L2 (see FIG. 3) from the position irradiated with the excitation light L10 is incident, and a sensor 41 that detects the acted light L2 emitted from the optical filter 42. The sensor 41 is controlled by a detection control unit 85. The optical filter 42 is disposed so as to face the detection surface of the acted light L2 in the sensor 41 and to be located between the main surface 21a of the support plate 21 and the detection surface. That is, the optical filter 42 is disposed between the position irradiated with the excitation light L10 and the detection surface. The acted light L2 from the position irradiated with the excitation light L10 first enters the optical filter 42, and the acted light L2 that has been filtered leaves the optical filter 42 and enters the detection surface of the sensor 41.

[0043] The region of the radiation image forming layer 11 that is irradiated with radiation and accumulates radiation energy is excited by the excitation light L10. Therefore, the region of the radiation image forming layer 11 where radiation energy has accumulated and is within the range irradiated by the excitation light L10 can be said to be an excited region that is excited by the excitation light L10. Since a radiation image is recorded as a latent image in the excited region, the excited region can also be said to be a radiation image region, a latent image region, or an image recording region.

[0044] Fig. 7 is an enlarged schematic diagram of the photodetector 40 and its periphery in Fig. 3. When the excited region of the radiation image forming layer 11 is irradiated with excitation light L10, the excited region emits light in accordance with the distribution of energy stored in the excited region, and stimulated light L5 is emitted from the excited region. The stimulated light L5 is, for example, blue visible light. When the excited region of the radiation image forming layer 11 is irradiated with excitation light L10, reflected light of the excitation light L10 at the excited region (hereinafter also referred to as reflected light L4) is generated. The reflected light L4 may be called excited region reflected light L4. Luminescent light L2, which will be described later and is an example of interacted light L2, may be considered to be light whose emission origin is the imaging plate 10, not due to reflection. The stimulated light L5 is a specific example of the luminescent light L2.

[0045] The light from the excited region (hereinafter, also referred to as excited region light L20) includes stimulated light L5 emitted by the excited region and reflected light L4 from the excited region. The excited region light L20 can also be called radiation image region light, latent image region light, or image recording region light. The excited region light L20 is light that includes at least stimulated light L5. When the excited region is a latent image region in the irradiated range of the exciting light L10 that is excited when irradiated with the exciting light L10, specifically, a region that is excited and emits stimulated light L5, the excited region light L20 is light that includes at least stimulated light L5 from the excited region. In the above example, the excited region light L20 is light that includes stimulated light L5 and reflected light L4, but as described later, the excited region light L20 may be composed of only stimulated light L5.

[0046] The acted light L2 incident on the optical filter 42 includes the excited region light L20. The excited region light L20 is filtered by the optical filter 42 and then incident on the sensor 41. In this example, the transmittance (also called the stimulated light transmittance) of the optical filter 42 for the stimulated light L5 is very high. Therefore, the optical filter 42 transmits the stimulated light L5 from the excited region of the imaging plate 10 sufficiently and outputs it to the sensor 41. On the other hand, the transmittance (also called the excitation light transmittance) of the optical filter 42 for the excitation light L10 is lower than the stimulated light transmittance. For example, an optical filter 42 with an excitation light transmittance of about 10% of the stimulated light transmittance may be used. The optical filter 42 attenuates the reflected light L4 of the excitation light L10 at the excited region of the imaging plate 10, which is directed toward the sensor 41. The optical filter 42 attenuates the excitation light L10, but transmits the excitation light L10 to a certain extent. Therefore, in this example, the sensor 41 detects not only the stimulated light L5 but also the reflected light L4 of the excitation light L10 at the excited region to some extent. Therefore, the excited region light L20 emitted from the optical filter 42 contains the stimulated light L5 and the reflected light L4.

[0047] The sensor 41 detects the excited region light L20 transmitted through the optical filter 42 and can output an electrical signal according to the intensity of the detected excited region light L20. The sensor 41 may be composed of, for example, a plurality of photodiodes or a photomultiplier tube. In this example, the acted light L2 detected by the sensor 41 (in other words, the acted light L2 detected by the detector 40) includes, for example, stimulated emission L5 and reflected light L4.

[0048] 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 holder 20 holding the imaging plate 10 is transported to a reading start position by the drive unit 50. Then, the light measurement device 90 starts the reading process. In the reading process, the light source 30 repeatedly executes a process of scanning the imaging plate 10 in a main scanning direction DRm with the excitation light L10 under the control of the light emission control unit 86 (also referred to as a main scanning direction scan). Meanwhile, in the reading process, the drive unit 50 moves the holder 20 holding the imaging plate 10 in one direction DRs (also referred to as a 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 holder 20 is moving in the sub-scanning direction DRs, the main scanning direction scan is repeatedly executed, whereby the excitation light L10 is irradiated to the radiation image forming layer 11 of the imaging plate 10 with a two-dimensional spread, and the radiation image forming layer 11 is raster scanned. As a result, in the reading process, the stimulating light L10 is sequentially irradiated over the entire area of ​​the radiation image forming layer 11, and the entire area of ​​the radiation image forming layer 11 is scanned with the stimulating light L10. While the radiation image forming layer 11 is raster scanned with the stimulating light L10, the sensor 41 of the detector 40 detects the excited area light L20 (i.e., light including stimulated emission L5) arriving sequentially from the radiation image forming layer 11 in response to the raster scan, thereby reading out a radiation image from the radiation image forming layer 11. The sensor 41 outputs an image signal representing the read out radiation image (in other words, the detected radiation image) to the detection control unit 85 as a detection result of the excited area light L20 during the raster scan of the stimulating light L10. This image signal includes brightness values ​​(in other words, pixel values) of a plurality of pixels representing the read out radiation image. The sensor 41 outputs, for example, a grayscale image signal. Hereinafter, the radiation image read by the detector 40 may be referred to as a detected radiation image.

[0049] The scanning of the excitation light L10 may be performed two-dimensionally by determining the coordinates over the entire detection range of the imaging plate 10, and the main scanning direction DRm and the sub-scanning direction DRs may not be perpendicular to each other. For example, the main scanning direction DRm and the sub-scanning direction DRs may intersect at an angle other than perpendicular. In addition, one or both of the main scanning direction DRm and the sub-scanning direction DRs may be set to a curved direction.

[0050] 2 and 4, when the imaging plate 10 is appropriately held by the holder 20, the short side direction of the imaging plate 10 is parallel to the main scanning direction DRm, and the long side direction of the imaging plate 10 is parallel to the sub-scanning direction DRs. Here, the posture of the imaging plate 10 when the imaging plate 10 is appropriately held by the holder 20 is called the reference posture. In this example, the reference posture is a posture of the imaging plate 10 in which the short side direction of the imaging plate 10 is parallel to the main scanning direction DRm, and the long side direction of the imaging plate 10 is parallel to the sub-scanning direction DRs. Note that the reference posture is not limited to this.

[0051] The imaging plate 10 is basically held in the reference position by the holding part 20. However, if the holding part 20 does not hold the imaging plate 10 properly due to a malfunction of the fixing part 22 or the like, the imaging plate 10 may be held by the holding part 20 in a state tilted from the reference position.

[0052] In this example, the sensor 41 outputs a larger luminance value, for example, as the intensity of the detected light increases. In the radiation image forming layer 11 of the imaging plate 10, the intensity of stimulated emission L5 from a portion where the radiation irradiation intensity is higher and the stored energy is greater is higher. On the other hand, the intensity of reflected light L4 from the excited region is almost constant regardless of the stored energy, so long as the intensity of excitation light L10 is constant. Therefore, the luminance value output by the sensor 41 for an image based on detection of excited region light L20 from a portion of the excited region of the radiation image forming layer 11 where the stored energy is large becomes larger.

[0053] For example, consider a case where a radiation image of teeth is recorded in the radiation image forming layer 11. In this case, the intensity of the excited region light L20 from the part of the excited region of the radiation image forming layer 11 where the radiation image of the teeth is recorded, i.e., the part irradiated with radiation that has passed through the teeth, is relatively low. Therefore, the luminance value output by the sensor 41 for the part of the detected radiation image where the teeth are shown is relatively low. On the other hand, the intensity of the excited region light L20 from the part of the excited region of the radiation image forming layer 11 that is directly irradiated with radiation (also referred to as the directly irradiated part) is relatively high. Therefore, the luminance value output by the sensor 41 for the image of the detected radiation image that corresponds to the directly irradiated part of the radiation image forming layer 11 is relatively high.

[0054] As described above, in this example, the sensor 41 detects not only the stimulated light L5 emitted by the excited region of the imaging plate 10, but also to a certain extent the reflected light L4 from the excited region of the imaging plate 10. Therefore, the luminance value of the detected radiation image output from the sensor 41 includes a luminance value corresponding to the intensity of the detected stimulated light L5 (also referred to as a luminance value corresponding to stimulated light) and a luminance value corresponding to the detected reflected light L4 (also referred to as a luminance value corresponding to reflected light).

[0055] The stimulated light-corresponding luminance value is, for example, 10 times or more the reflected light-corresponding luminance value under standard dose and distance (SID: Source Image Distance) conditions. Therefore, the detected radiation image based on the image signal output from the detector 40 is not significantly affected by the reflected light L4, and the reflected light L4 is unlikely to interfere with the reading of the radiation image recorded on the imaging plate 10 and its subsequent processing. In the excited region light L20 detected by the sensor 41, the stimulated light L5 has a higher luminance intensity ratio than the reflected light L4, so the reflected light L4 has little effect. Therefore, the detector 40 outputs an electrical signal corresponding to the intensity of the stimulated light L5 by outputting an electrical signal corresponding to the intensity of the detected excited region light L20.

[0056] In this example, the radiation image forming layer 11 of the imaging plate 10 may have unexposed portions where energy corresponding to the irradiation of radiation has not been accumulated. For example, when the imaging plate 10 is irradiated with radiation through an object to be photographed, the radiation image forming layer 11 may have unexposed portions where the radiation should not be irradiated due to a misalignment of the light source emitting the radiation. These unexposed portions are sometimes called cone cuts. In this example, the imaging plate 10 is placed in the mouth to receive radiation. Therefore, since the imaging plate 10 is entirely or partially hidden in the mouth, even if the operator intends to appropriately position the light source emitting the radiation, the irradiation range of the radiation may deviate from the entirety or part of the imaging plate 10. In such a case, a cone cut occurs. In addition, the radiation image may unintentionally disappear from the portion of the radiation image forming layer 11 irradiated with radiation, resulting in partial unexposed portions. For example, the imaging plate 10 for recording radiation images is usually stored covered with a cover to prevent it from being exposed to ambient light. However, if the imaging plate 10 is not properly covered, a part of the radiation image forming layer 11 may be exposed to ambient light during storage of the imaging plate 10, and the radiation image recorded in that part may be unintentionally erased. In this case, too, the radiation image forming layer 11 will have a partially unexposed portion (here, a portion that was once exposed but has returned to an unexposed state by erasure).

[0057] Since no radiation energy is accumulated in the unexposed portion of the imaging plate 10, the unexposed portion is not excited even if the unexposed portion is irradiated with the excitation light L10. Therefore, the unexposed portion is not an excited region, that is, a non-excited region. Even if the unexposed portion (in other words, the non-excited region) of the imaging plate 10 is irradiated with the excitation light L10, the unexposed portion does not emit stimulated light L5. Therefore, when the excitation light L10 is irradiated to the unexposed portion, as shown in FIG. 8, the detector 40 detects the reflected light of the excitation light L10 from the unexposed portion without detecting the stimulated light L5. Therefore, the image signal output by the detector 40 may include the luminance values ​​of a plurality of pixels representing an image of the unexposed portion, that is, an image based on the detection of the reflected light of the excitation light L1 from the unexposed portion. Hereinafter, the reflected light of the excitation light L10 from a region of the imaging plate 10 where no radiation energy is accumulated, such as the unexposed region, is called the reflected light L40.

[0058] The reflected light L40 from the unexposed portion passes through an optical filter 42 and enters the sensor 41. The entire image based on the image signal output by the detector 40 as a detection result of the excited region light L20 and the reflected light L40 may include not only a detected radiation image based on the detection of the excited region light L20 but also an image of the unexposed portion (also called an unexposed region image). The luminance value of the detected radiation image output by the detector 40 is, for example, 10 times or more the luminance value of the unexposed region image output by the detector 40 under standard dose and distance (SID) conditions. The reflected light L40 from the unexposed portion, i.e., the non-excited region, may also be called non-excited region light. The reflected light L40 may also be called non-excited region reflected light L40. The interacted light L2 detected by the detector 40 also includes the reflected light L40.

[0059] When no radiation image is recorded on the imaging plate 10, the sensor 41 does not detect the excited region light L20, but detects reflected light L40 from the position irradiated with the excitation light L10. The reflected light of the excitation light L10 on the imaging plate 10, such as the reflected light L40 from the non-excited region and the reflected light L4 from the excited region, may be expressed as non-stimulated reflected light in contrast to the stimulated light L5. Furthermore, regardless of whether the excitation light L10 is reflected on the imaging plate 10 or outside the imaging plate 10, the reflected light of the excitation light L10 may be simply called reflected light.

[0060] In the present disclosure, the name of the light from the imaging plate 10 or the name of the light irradiated to the imaging plate 10 may be given IP, which represents the imaging plate 10. For example, the excited region light L20 may be called IP excited region light L20. The non-excited region light may be called IP non-excited region light. The stimulated light L5 may be called IP stimulated light L5. The reflected light L4 may be called IP reflected light L4 (also called IP excited region reflected light L4), and the reflected light L40 may be called IP reflected light L40 (also called IP non-excited region reflected light L40). The non-stimulated reflected light may be called IP non-stimulated reflected light. The action light L1 may be called IP action light L1, and the acted light L2 may be called IP acted light L2. The IP acted light L2 may simply be called IP light L2. The excitation light L10 may be called IP excitation light L10. Hereinafter, when there is no need to particularly distinguish between the reflected lights L4 and L40, each of them or a combination of both will be referred to as IP reflected light.

[0061] The excitation light L10 has a component that generates stimulated light L5. The excitation light L10 also has a component that generates IP reflected light. The light source 30 is also a stimulated light generating light source that serves as a source of light that has a component that generates stimulated light L5. The light source 30 is also a reflected light generating light source that serves as a source of light that has a component that generates IP reflected light. For example, the light source 30 as a stimulated light generating light source is a first light source, and the light source 30 as a reflected light generating light source is a second light source. The stimulated light generating light source and the reflected light generating light source do not need to be the same body, and may be provided separately. The reflected light generating light source is not limited to the excitation light L10, and may be any light source that can irradiate light that generates reflected light from an object.

[0062] The sensor 41 is a photo-stimulated light detector that detects the photo-stimulated light L5, and is also a reflected light detector that detects the IP reflected light. For example, the sensor 41 as a photo-stimulated light detector that detects the photo-stimulated light is a first detector, and the sensor 41 as a reflected light detector that detects the reflected light is a second detector. The sensor 41 is a detector that detects the excited region light L20. Since the excited region light L20 is light that contains at least the photo-stimulated light L5, at least the photo-stimulated light L5 is detected by detecting the excited region light L20. In that sense, the sensor 41 is a photo-stimulated light detector. The sensor 41 as the first detector may be considered as an excited region light detector. Since the excited region light is IP acted upon light, the first detector may be considered as an IP excited region light detector that detects the IP excited region light L20. The second detector may be considered as a non-excited region light detector that detects the non-excited region light. When the non-excited region light is IP acted upon light, the second detector may be considered as an IP non-excited region light detector that detects the IP non-excited region light. The photostimulated light detector and the reflected light detector do not have to be integrated, and may be provided separately.

[0063] In addition, in the present disclosure, an image formed by a certain light, that is, an image based on the detection of a certain light, may be called an image with the name of the certain light. For example, an image formed by the excited region light L20, that is, an image based on the detection of the excited region light L20, may be called an excited region light image. The above-mentioned detected radiation image obtained by the detector 40 is an excited region light image. Also, an image formed by reflected light, that is, an image based on the detection of the reflected light, may be called a reflected light image. The reflected light image formed by the reflected light L40 from the unexposed part is the above-mentioned unexposed region image obtained by the detector 40. An image formed by non-stimulated reflected light may be called a non-stimulated reflected light image, and an image formed by the acted light L2 may be called an acted light image. Therefore, there may be a stimulated light image, a reflected light image, an excited region reflected light image, a non-excited region light image, a non-excited region reflected light image, and so on.

[0064] In addition, in the present disclosure, the name of an image related to the imaging plate 10 may be given with IP, which represents the imaging plate 10. For example, the excited region light image may be called the IP excited region light image, the image formed by the IP reflected light (in other words, an image based on the detection of the IP reflected light or an image obtained by the detection of the IP reflected light) may be called the IP reflected light image, the non-photostimulable reflected light image may be called the IP non-photostimulable reflected light image, and the acted light image may be called the IP acted light image. Similarly, there may be an IP photostimulated light image, an IP excited region reflected light image, an IP non-excited region light image, an IP non-excited region reflected light image, and so on. The IP acted light image may also be simply called the IP image. Furthermore, an IP acted light image that has been processed may also be called the IP acted light image (in other words, an IP image).

[0065] In addition, in the present disclosure, an image signal obtained as a result of detecting a certain light may be called an image signal with the name of the certain light. For example, an image signal obtained as a result of detecting excited region light L20 may be called an excited region light image signal. An image signal obtained as a result of detecting reflected light may be called a reflected light image signal. An image signal obtained as a result of detecting a non-stimulated reflected light image may be called a non-stimulated reflected light image signal. An image signal obtained as a result of detecting acted light L2 may be called an acted light image signal. Similarly, there may be a stimulated light image signal, an excited region reflected light image signal, a non-excited region light image signal, a non-excited region reflected light image signal, etc.

[0066] In addition, in the present disclosure, the name of the image signal related to the imaging plate 10 may be given IP, which represents the imaging plate 10. For example, the excited region light image signal may be called IP excited region light image signal, the image signal obtained as the detection result of the reflected light may be called IP reflected light image signal, the non-stimulated reflected light image signal may be called IP non-stimulated reflected light image signal, and the acted light image signal may be called IP acted light image signal. Also, the IP acted light image signal may simply be called IP image signal. Similarly, there may be IP stimulated light image signal, IP excited region reflected light image signal, IP non-excited region light image signal, IP non-excited region reflected light image signal, etc.

[0067] If the optical filter 42 completely blocks the reflected light L4 and transmits only the stimulated light L5 as shown in Fig. 9, the acted light L2 detected by the sensor 41, in other words, the excited region light L20 detected by the sensor 41, will be the stimulated light L5. Therefore, the luminance value corresponding to the intensity of the acted light L2 (in other words, the excited region light L20) output from the sensor 41 will be the luminance value corresponding to the intensity of the stimulated light L5. In the example of Fig. 9, the image based on the stimulated light L5 detected by the detector 40 may be called a stimulated light image or an IP stimulated light image. Moreover, the image signal output by the detector 40 as the detection result of the stimulated light L5 may be called a stimulated light image signal or an IP stimulated light image signal.

[0068] In this example, in the reading process, the excitation light L10 is irradiated not only to the imaging plate 10 but also to a portion of the holder 20 outside the imaging plate 10. Here, the object irradiated with the excitation light L10 in the reading device 1 is called an irradiation object 1200. In this example, the irradiation object 1200 is composed of the holder 20 and the imaging plate 10 held by the holder 20. In addition, the main surface 1200a of the irradiation object 1200 on the support surface 21a side is called the support-side main surface 1200a. In this example, the support-side main surface 1200a includes the surface of the radiation image forming layer 11 of the imaging plate 10, the surface of the fixing portion 22 of the holder 20, and an area of ​​the support surface 21a of the support plate 21 of the holder 20 that is not covered by the imaging plate 10 and the fixing portion 22. In addition, the area of ​​the support-side main surface 1200a where the image formed by the acted light L2 therefrom is an IP image is called an IP image area R100. The IP image region R100 can be said to be an IP presence region where the imaging plate 10 is present on the support-side principal surface 1200a. The principal surface of the irradiation target 1200 opposite to the support-side principal surface 1200a coincides with the rear surface 21b of the support plate 21.

[0069] The light from the IP image region R100 may be called IP image region light. The image formed by the IP image region light may be called IP image region light image. The image signal output as the detection result of the IP image region light may be called IP image region light image signal. The IP image region light may consist of only excited region reflected light L4, only non-excited region reflected light L40, or both excited region reflected light L4 and non-excited region reflected light L40.

[0070] In this example, the irradiation range R120 of the excitation light L10 on the support-side principal surface 1200a in the reading process (also referred to as the excitation light irradiation range) includes the IP image region R100 but is larger than it. The excitation light irradiation range R120 can also be said to be the scanning range of the excitation light L10 in the reading process. In addition, the detection range R110 of the detector 40 on the support-side principal surface 1200a in the reading process also includes the IP image region R100 but is larger than it.

[0071] FIG. 10 is a schematic diagram showing an example of an excitation light irradiation range R120, a detection range R110, and an IP image region R100. In FIG. 10 and in FIGS. 12 and 13 described later, the imaging plate 10 is omitted. As shown in FIG. 10, the excitation light irradiation range R120 and the detection range R110 each include the IP image region R100 and are larger than the IP image region R100. The excitation light irradiation range R120 and the detection range R110 are, for example, the same size as each other and exist at the same position as each other. Note that, for convenience of explanation, in FIG. 10, the excitation light irradiation range R120 is shown slightly larger than the detection range R110.

[0072] In this way, the excitation light irradiation range R120 and the detection range R110 may be set to be the same range. The configuration in which only the interacted light L2 from the excitation light irradiation range R120 is the detection target is an example of a configuration in which the excitation light irradiation range R120 and the detection range R110 are set to be the same range.

[0073] In the reading process, the light source 30 repeatedly executes scanning in the main scanning direction while the holder 20 holding the imaging plate 10 moves in the sub-scanning direction DRs, thereby performing raster scanning with the excitation light L10 in the excitation light irradiation range R120. The sensor 41 sequentially outputs luminance values ​​according to the irradiation position of the excitation light L10 in the detection range R110 in response to the raster scanning of the excitation light L10.

[0074] Here, the region on the support side main surface 1200a that is outside the IP image region R100 and inside the excitation light irradiation range R120 and the detection range R110 is called the IP outer region R130. In this example, the excitation light irradiation range R120 and the detection range R110 include the IP image region R100 but are larger than the IP image region R100, so the sensor 41 detects the reflected light L400 of the excitation light L10 from the IP outer region R130. The IP outer region R130 includes, for example, at least a part of the surface of the fixing portion 22 and at least a part of the region of the support surface 21a of the support plate 21 that is not covered by the imaging plate 10 and the fixing portion 22. The IP outer region R130 is included in the surface of the holding portion 20, specifically, in the main surface of the holding portion 20 on the imaging plate 10 side. FIG. 11 is a schematic diagram showing an example of how the sensor 41 detects the reflected light L400. The acted light L2 detected by the sensor 41 also includes reflected light L400.

[0075] Even if the IP outer region R130 is irradiated with the excitation light L10, the IP outer region R130 does not emit the stimulated emission L5. Therefore, when the IP outer region R130 is irradiated with the excitation light L10, the detector 40 does not detect the stimulated emission L5, but detects the reflected light L400 of the excitation light L10 from the IP outer region R130. Therefore, in the reading process, the image signal output by the detector 40 as the detection result of the stimulated emission L5 and the reflected light includes the luminance values ​​of a plurality of pixels representing the reflected light image of the IP outer region R130, that is, the reflected light image based on the detection of the reflected light L400 of the excitation light L10 from the IP outer region R130. In this example, the overall image based on the image signal output by the detector 40 (also referred to as the acquired overall image) includes not only the detected radiation image but also the reflected light image of the IP outer region R130. When the imaging plate 10 includes an unexposed portion, the acquired overall image includes the detected radiation image, the unexposed region image, and the reflected light image of the IP outer region R130. Hereinafter, the reflected light image of the IP outer region R130 may be referred to as an IP outer region image.

[0076] In the detection range R110, the area excluding the IP image area R100 may be called the IP image area outside area. The image of the IP image area outside area may be called the IP image area outside area image. The detection range R110 is set to include at least the IP image area R100. When the detection range R110 is set to include the IP image area R100 but is wider than the IP image area R100, the detection range R110 is composed of the IP image area R100 and the IP image area outside area. The IP image area R100 is an area in the imaging plate 10 that receives the excitation light L1, and therefore may be called the IP light receiving area. In the detection range R110, the area excluding the IP light receiving area is the IP image area outside area, and therefore the IP image area outside area may be called the IP light receiving area.

[0077] In this example, the IP outer region R130 is subjected to a process that makes the excitation light L10 less likely to be reflected. For example, the IP outer region R130 is subjected to a black anodizing process. This makes it more difficult for the detector 40 to detect the reflected light L400 of the excitation light L10 in the IP outer region R130 than the reflected light L40 of the excitation light L10 in the unexposed portion of the imaging plate 10. In this example, the IP outer region R130 is hardly reflected with the black anodizing process. The brightness value of the unexposed region image output by the detector 40 is, for example, three times or more the brightness value of the IP outer region image output by the detector 40. The black anodizing process may also be performed on regions of the surface of the holder 20 other than the IP outer region R130. For example, the black anodizing process may be performed on the entire surface of the holder 20. Furthermore, for example, a treatment may be performed on at least a range within the detection range R110 of the support surface 21a and the fixing portion 22 of the holding portion 20 that is irradiated with the excitation light L1, so as to make the excitation light L10 less likely to be reflected. When there is a range within the detection range R110 of the support surface 21a and the fixing portion 22 of the holding portion 20 that is not irradiated with the excitation light L10, this range may also be treated to make the light less likely to be reflected.

[0078] The relationship between the excitation light irradiation range R120, the detection range R110, and the IP image region R100 is not limited to the above example. Figures 12 and 13 are schematic diagrams showing other examples of the excitation light irradiation range R120, the detection range R110, and the IP image region R100. In the example of Figure 12, the excitation light irradiation range R120 includes the detection range R110 and the IP image region R100, and is larger than the detection range R110 and the IP image region R100. In the example of Figure 12, the IP image region outside region in the detection range R110 is contained in the excitation light irradiation range R120. The region within the detection range R110, within the excitation light irradiation range R120, and outside the IP image region R100 may be called the IP image region outside region within the irradiation range. The IP image region outside region within the irradiation range coincides with the above-mentioned IP outer region R130. In the example of Figure 12, the IP image region outside region is composed of the IP image region outside region within the irradiation range. Hereinafter, the IP outer region R130 may be referred to as the region R130 outside the IP image region within the irradiation range.

[0079] In the example of FIG. 13, the detection range R110 includes the excitation light irradiation range R120 and the IP image region R100, and is larger than the excitation light irradiation range R120 and the IP image region R100.

[0080] 10, 12, and 13, the excitation light irradiation range R120 and the detection range R110 may be the same, or one of the excitation light irradiation range R120 and the detection range R110 may be larger than the other of the excitation light irradiation range R120 and the detection range R110.

[0081] In the example of Fig. 13, the detection range R110 includes a region other than the excitation light irradiation range R120 (also referred to as an outside-irradiation range region) on the support-side main surface 1200a. In addition, in the example of Fig. 13, the outside-IP-image-region region in the detection range R110 includes a region in the excitation light irradiation range R120 excluding the IP image region R100 and a region in the detection range R110 excluding the excitation light irradiation range R120. A region outside the excitation light irradiation range R120 in the detection range R110 may be referred to as an outside-IP-image-region region outside the irradiation range. In the example of Fig. 13, the outside-IP-image-region region in the detection range R110 is composed of an inside-irradiation-range IP-image-region region outside the irradiation range and an outside-IP-image-region region outside the irradiation range.

[0082] The excitation light irradiation range R120 of the support-side main surface 1200a may be treated to make the excitation light L1 less likely to be reflected, and the region outside the irradiation range IP image region may also be treated to make the light less likely to be reflected. The light condition of the region outside the irradiation range IP image region may be called the light condition of the region outside the irradiation range IP image region.

[0083] In the reading process, an outside-illumination-range detection process is performed for the outside-illumination-range IP image area region. As the outside-illumination-range detection process, the detector 40 may detect the brightness of the outside-illumination-range IP image area region light situation. Since it is known that the brightness of the outside-illumination-range IP image area region light situation is low, for the sake of efficiency, for example, the brightness values ​​of the outside-illumination-range IP image area region light situation may be set to a predetermined value all at once, and the brightness of the outside-illumination-range IP image area region light situation may be detected. The predetermined value is a brightness value lower than the brightness value of the IP image. The image signal output by the detector 40 also includes the brightness value of the outside-illumination-range IP image area region light situation.

[0084] In this way, even if light does not come out of the IP image area outside the irradiation range, an image of the IP image area outside the irradiation range can be obtained in the reading process. A process may be performed to make the excitation light L1 less likely to be reflected by the IP image area outside the irradiation range. In this case, a process may be performed to make the excitation light L1 less likely to be reflected by at least the IP image area outside the irradiation range.

[0085] An image signal obtained as a result of detecting the acted-on light L2 from the detection range R110 may be called a detection range image signal. An image based on the detection range image signal may be called a detection range image. The detection range image is the above-mentioned acquired overall image.

[0086] The image of the area outside the IP image area may be called the IP image area outside area image. The image of the area outside the IP image area within the irradiation range may be called the IP image area outside area image within the irradiation range. The image of the area outside the IP image area outside the irradiation range may be called the IP image area outside area image outside the irradiation range. In the case of FIG. 12, the image of the IP image area outside area within the irradiation range constitutes the IP image area outside area image. In the case of FIG. 13, the image of the IP image area outside area within the irradiation range and the image of the IP image area outside area outside the irradiation range constitute the IP image area outside area image.

[0087] When the excitation light L1 is irradiated onto the IP image area outside region R130 within the irradiation range (i.e., the IP outside region R130), a reflected light L400 is generated, although the reflected light L400 has low luminance, and when this reflected light L400 is detected by the detector 40, the image of the IP image area outside region within the irradiation range (i.e., the IP outside region image) is a reflected light image. The image of the IP image area outside region outside the irradiation range is a dark image due to the dark current of the pixels on the detection surface of the sensor 41, or is a dark image generated by being given an artificially low value. The image of the IP image area outside region is an image consisting of a reflected light image of the IP image area outside region within the irradiation range, or an image consisting of a reflected light image of the IP image area outside region within the irradiation range and a dark image of the IP image area outside region outside the irradiation range.

[0088] <About the erasing light source> In this embodiment, as shown in FIG. 6, an erasing unit 91 that performs an erasing process for erasing a radiation image from an imaging plate 10 is constituted by an erasing light source 70 and an erasing control unit 87 that controls the erasing light source 70. The erasing light source 70 and the erasing control unit 87 that constitute the erasing unit 91 may be housed in one case and unitized, or may not be housed in one case. The erasing light source 70 is capable of irradiating the imaging plate 10 with erasing light L3 for erasing a 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 visible light of another color. The erasing light source 70 may be an LED (Light Emission Diode), a halogen lamp, or another light source.

[0089] 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 forming layer 11 is irradiated with the erasing light L3, whereby the radiation image is erased from the radiation image forming layer 11.

[0090] When the reading process is completed, the drive unit 50 moves the holder 20 holding the imaging plate 10 to the erasing position. When the holder 20 moves to the erasing position, the erasing unit 91 performs the erasing process. In the erasing process, the erasing light source 70, under the control of the erasing control unit 87, irradiates the entire area of ​​the radiation image forming layer 11 of the imaging plate 10 with the erasing light L3. This erases the radiation image from the imaging plate 10.

[0091] When the radiation image is erased from the imaging plate 10, the drive unit 50 moves the holding unit 20 to the ejection position. When the holding unit 20 moves to the ejection position, each fixed portion 22a of the holding unit 20 moves from the approach position to the separate position. Thereafter, the imaging plate 10 from which the radiation image has been erased is ejected to the outlet 2b. Hereinafter, the term "erased imaging plate 10" refers to the imaging plate 10 from which the radiation image has been erased.

[0092] <About the image processing unit> The image processing unit 81 of the control unit 80 associates the luminance value contained in the image signal from the sensor 41 with each pixel position in the captured overall image.

[0093] 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 the main scanning direction scan. Specifically, while the main scanning direction scan is performed a predetermined number of times, 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 L10. Then, the sensor 41 sequentially outputs a luminance value according to the irradiation position of the excitation light L10 in the detection range R110 in accordance with the raster scan of the excitation light L10. Since the reading device 1 operates in this manner in the reading process, if the excitation light irradiation range R120, the detection range R110, the time required for one main scanning direction scan, the repetition period of the main scanning direction scan, and the number of times the main scanning direction scan is performed in the reading process are known, it is possible to know at what position in the entire acquired image the luminance value output by the sensor 41 at a certain timing corresponds to the luminance value of the pixel. The image processing unit 81 associates a plurality of luminance values ​​included in the image signal from the sensor 41 with a plurality of pixel positions based on the excitation light irradiation range R120, the detection range R110, the time required for one main scanning scan, the repetition period of the main scanning scan, and the number of times the main scanning scan is performed in the reading process. Note that the detection control unit 85 may associate a plurality of luminance values ​​included in the image signal from the sensor 41 with a plurality of pixel positions.

[0094] Furthermore, the image processing unit 81 performs image processing on the image signal from the sensor 41. The image processing unit 81 processes the image signals (detected image signals) from the sensors 41 which are the first and second detectors. The image processing unit 81 outputs image information in which a plurality of luminance values ​​of the image signal after image processing are associated with a plurality of pixel positions in the acquired overall image to the display control unit 82. The display control unit 82 causes the display unit 3 to display the acquired overall image including the detected radiation image, for example, based on the image information.

[0095] The image processing performed by the image processor 81 may include a luminance inversion process. The luminance inversion process is a process in which each luminance value of the image signal before the luminance inversion process is converted so that the luminance value becomes smaller as the luminance value becomes larger. Here, the maximum value of the range in which the luminance value can be taken is called the maximum luminance value. For example, a value obtained by subtracting a certain luminance value contained in the image signal before the luminance inversion process from the maximum luminance value becomes the certain luminance value after conversion. By performing the luminance inversion process on the image signal, the luminance value of the radiation image based on the detection of the excited region light L20 from a portion of the imaging plate 10 with a small amount of accumulated energy becomes larger in the image signal after the image processing, unlike the image signal before the image processing, and the luminance value of the radiation image based on the detection of the excited region light L20 from a portion of the imaging plate 10 with a large amount of accumulated energy becomes smaller. Furthermore, in the image signal after the image processing, the luminance value of the unexposed region image and the luminance value of the IP outer region image become larger than the luminance value of the detected radiation image.

[0096] 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. The image processing may include, for example, offset correction and logarithmic conversion as processing other than the luminance inversion processing.

[0097] 14 and 15 are schematic diagrams showing an example of an acquired overall image (also called pre-inversion overall image) 100a based on an image signal before brightness inversion processing is performed. FIGS. 16 and 17 are schematic diagrams showing an example of an acquired overall image (also called post-inversion overall image) 100b based on an image signal after brightness inversion processing is performed. In FIGS. 14 to 17, the pre-inversion overall image 100a and the post-inversion overall image 100b are shown in grayscale. In FIGS. 14 to 17, the higher the brightness value of an image, the brighter the image is shown (in other words, whiter), and the lower the brightness value of an image, the darker the image is shown (in other words, blacker). The same applies to the figures shown below showing images obtained by the reading device 1.

[0098] An image obtained by scanning an imaging plate 10 used as a photoreceptor for radiography of a living body with actinic light L1 for the purpose of reading a radiographic image of living tissue, as shown in the acquired overall image 100a of Fig. 14, is referred to as a living body radiography image. Scanning may be performed with excitation light L10 as the actinic light L1. As shown in the radiography image 101a of Fig. 14, an image formed by IP actinic light L2 in the living body radiography image (in other words, an image based on detection of IP actinic light L2) is referred to as an IP living body radiography image. Both the living body radiography image and the IP living body radiography image are images obtained by radiography of a living body, and are acquired images obtained from living body radiography.

[0099] FIG. 14 shows a pre-inversion overall image 100a including a radiation image (in other words, a detected radiation image or an IP excited region light image) 101a based on detection of the excited region light L20 and an IP image region outside region image 102a. In the example of FIG. 14, the radiation image 101a constitutes an IP image. FIG. 15 shows a pre-inversion overall image 100a including a radiation image (in other words, an IP excited region light image) 101a, an IP image region outside region image 102a, and an unexposed region image (in other words, an IP reflected light image or an IP non-photostimulable reflected light image) 103a. In the example of FIG. 15, the radiation image 101a and the unexposed region image 103a constitute an IP image. FIG. 16 shows a post-inversion overall image 100b including a radiation image (in other words, an IP excited region light image) 101b and an IP image region outside region image 102b. In the example of FIG. 16, the radiation image 101b constitutes an IP image. Fig. 17 shows an inverted overall image 100b including a radiation image (in other words, an IP excited region light image) 101b, an IP image region outside image 102b, and an unexposed region image (in other words, an IP reflected light image or an IP non-stimulable reflected light image) 103b. In the example of Fig. 17, the radiation image 101b and the unexposed region image 103b constitute an IP image. In this example, since the detection range R110 of the sensor 41 is rectangular, the shape of the obtained overall image is rectangular as shown in Figs. 14 to 17.

[0100] When the display control unit 82 causes the display unit 3 to display the inverted overall image 100b based on the image signal after image processing, the display control unit 82 causes the display unit 3 to display the inverted overall image 100b in a grayscale as shown in Figs. 16 and 17, for example. Figs. 16 and 17 can also be said to be diagrams showing a display example of the inverted overall image 100b. When the display control unit 82 causes the display unit 3 to display the pre-inversion overall image 100a based on the image signal before the luminance inversion process, the display control unit 82 causes the display unit 3 to display the pre-inversion overall image 100a in a grayscale as shown in Figs. 14 and 15, for example. Figs. 14 and 15 can also be said to be diagrams showing a display example of the pre-inversion overall image 100a.

[0101] <An example of the operation of the reading device> Fig. 18 is a diagram showing a flowchart illustrating an example of the operation of the reading device 1. When the imaging plate 10 inserted through the insertion opening 2a of the housing 2 is held by the holding unit 20 and the start button included in the operation unit 4 is operated, step s1 in Fig. 14 is executed. The operation of the start button can also be said to be an operation to instruct the start of the series of processes shown in Fig. 14.

[0102] In step s1, the drive unit 50 moves the holder 20 to a reading start position under the control of the drive control unit 83. Next, in step s2, a reading process is performed in which a radiation image is read from the imaging plate 10. Next, in step s3, the drive unit 50 moves the holder 20 to an erasing position under the control of the drive control unit 83. Next, in step s4, the erasing light source 70 irradiates the imaging plate 10 with erasing light L3 under the control of the erasing control unit 87, thereby performing an erasing process in which the radiation image is erased from the imaging plate 10. Next, in step s5, the drive unit 50 moves the holder 20 to an ejection position under the control of the drive control unit 83. Next, in step s6, the imaging plate 10 is ejected to the ejection port 2b of the housing 2. Then, in step s7, the display unit 3 displays the acquired overall image under the control of the display control unit 82. In step s7, the display unit 3 displays the inverted overall image in grayscale, for example, as shown in Figs. 16 and 17. Note that step s7 may be performed at any time after step s2, for example, step s7 may be performed between steps s3 and s4.

[0103] <Identifying the tilt angle of the imaging plate> The image processing unit 81 may perform, for example, a tilt angle identification process for identifying the tilt angle (also referred to as IP tilt angle) of the imaging plate 10 from the reference posture. In the tilt angle identification process, the image processing unit 81 identifies the IP tilt angle based on, for example, the image signal output by the detector 40, specifically, the IP acted-on light image signal. The image processing unit 81 functions as an identification unit (also referred to as tilt angle identification unit) for identifying the IP tilt angle. In this example, the rotation angle from the reference posture can be detected by performing principal component analysis by regarding the existence area of ​​the imaging plate 10 as a two-dimensional feature vector set. A specific example of the tilt angle identification process will be described below, but the tilt angle identification process is not limited to the following example.

[0104] As described above, the reference posture in this example is a posture of the imaging plate 10 in which the short side direction and the long side direction of the imaging plate 10 are parallel to the main scanning direction DRm and the sub-scanning direction DRs, respectively. In other words, the reference posture is, for example, a posture of the imaging plate 10 in which the short side direction of the imaging plate 10 is parallel to the main scanning direction DRm and the long side direction of the imaging plate 10 is parallel to the sub-scanning direction DRs. If the holding unit 20 does not hold the imaging plate 10 appropriately, when the imaging plate 10 held by the holding unit 20 is viewed from its front side, as shown in FIG. 19, the long side direction (also called IP long side direction) of the imaging plate 10 may be inclined with respect to the sub-scanning direction DRs, and the imaging plate 10 may be inclined with respect to the reference posture. In other words, the short side direction (also called IP short side direction) of the imaging plate 10 may be inclined with respect to the main scanning direction DRm, and the imaging plate 10 may be inclined with respect to the reference posture. In FIG. 19, the imaging plate 10 in the reference posture is indicated by a dashed line.

[0105] In this example, the IP inclination angle, i.e., the inclination angle of the imaging plate 10 from the reference posture, is equal to the inclination angle of the IP long side direction with respect to the sub-scanning direction DRs, or in other words, the IP inclination angle is equal to the inclination angle of the IP short side direction with respect to the main scanning direction DRm.

[0106] On the other hand, the longitudinal direction of the detection range R110 (see FIG. 10, etc.) of the sensor 41 corresponds to the longitudinal direction of the acquired overall image 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 acquired overall 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 overall image and the longitudinal direction of the portion of the acquired overall image corresponding to the imaging plate 10 (also called the IP-equivalent portion) coincide with each other. On the other hand, when the imaging plate 10 is tilted with respect to the reference posture, the longitudinal direction of the IP-equivalent 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 short-side direction of the IP-equivalent portion included in the acquired overall image is tilted with respect to the short-side direction of the acquired overall image.

[0107] Fig. 20 is a diagram showing an example of a pre-inversion overall image 100a obtained when the imaging plate 10 is tilted with respect to the reference posture. The pre-inversion overall image 100a shown in Fig. 20 includes a tilted IP-equivalent portion 105a.

[0108] In this example, the tilt angle of the IP-corresponding portion (in other words, the IP image) in the longitudinal direction with respect to the longitudinal direction of the acquired overall image coincides with the IP tilt angle. Therefore, the image processing unit 81 obtains the tilt angle of the IP-corresponding portion in the longitudinal direction with respect to the longitudinal direction of the acquired overall image based on the image signal from the sensor 41. 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.

[0109] In the tilt angle identification process, the image processing unit 81 binarizes the entire pre-inversion image based on the image signal before the luminance inversion process (also referred to as the pre-inversion image signal) to generate a binarized image. First, the image processing unit 81 compares each luminance value of the entire pre-inversion image included in the pre-inversion image signal with a preset threshold value. Then, for each luminance value of the entire pre-inversion image, the image processing unit 81 replaces the luminance value equal to or greater than the threshold value with "1" and replaces the luminance value less than the threshold value with "0". As a result, the entire pre-inversion image is binarized to obtain a binarized image.

[0110] The threshold value used for binarization is set to a value that is, for example, greater than the luminance value of the out-of-IP-image region image included in the pre-inversion image signal and less than the luminance value of the unexposed region image included in the pre-inversion image signal. For example, consider a case where the luminance value of the out-of-IP-image region image included in the pre-inversion image signal is IL1 and the luminance value of the unexposed region image included in the pre-inversion image signal is IL2. Given that IL1 < IL2, in this case, the threshold value is set to IL3 such that IL1 < IL3 < IL2. The threshold value is set, for example, based on the pre-inversion image signal obtained by the reading device 1 before actual operation and is pre-stored in the image processing unit 81 of the reading device 1. Note that since the luminance value of the detected radiation image included in the pre-inversion image signal is greater than the luminance value of the unexposed region image included in the pre-inversion image signal (see FIG. 15), the threshold value is less than the luminance value of the detected radiation image included in the pre-inversion image signal.

[0111] By setting the threshold value as described above, in the binarized image, each luminance value of the portion corresponding to the out-of-IP-image region is "0". Also, regardless of whether the imaging plate 10 includes an unexposed portion, in the binarized image, each luminance value of the portion corresponding to the imaging plate 10 is "1".

[0112] FIG. 21 is a schematic diagram showing an example of a binarized image 500. FIG. 21 shows a binarized image 500 obtained by binarizing the pre-inversion overall image 100a shown in FIG. 20. In FIG. 21, in the binarized image 500, an area (also called a high brightness area) 501 having a brightness value of "1" is shown in white, and an area (also called a low brightness area) 502 having a brightness value of "0" is shown in black. As can be seen from FIG. 21, 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 area outside the IP image area. The outer shape of the high brightness area 501 corresponds to the outer shape of the imaging plate 10. The image of the high brightness area 501 (also called a high brightness area image) is also an IP image, and the image of the low brightness area 502 (also called a low brightness area image) is also an image of the area outside the IP image area.

[0113] The shape of the imaging plate 10 is referred to as the imaging plate shape, and data relating to the imaging plate shape (in other words, data representing the imaging plate shape) is referred to as the imaging plate shape data. The imaging plate shape data may include at least one of the size, shape, and inclination of the imaging plate 10. Furthermore, the process of extracting the imaging plate shape may be referred to as the imaging plate shape extraction process. The imaging plate shape data can be obtained from the imaging plate shape extraction process. Furthermore, an image obtained by photographing the imaging plate 10, such as the pre-inversion overall image 100a in FIG. 20, is referred to as the imaging plate photographed image.

[0114] An image representing the imaging plate shape obtained by processing an image obtained as a result of detecting the acted light generated by irradiating the imaging plate 10 with light, such as the binary image 500 in Fig. 21, is referred to as an imaging plate shape image. An image formed by processing the IP acted light and extracting the imaging plate shape, such as the image of the high luminance region 501 in Fig. 21, is referred to as an IP imaging plate shape image. Both the imaging plate shape image and the IP imaging plate shape image are composed of images representing the imaging plate shape extracted by processing the IP acted light image signal, and therefore may be referred to as imaging plate shape extraction images.

[0115] Here, the high brightness region 501 included in the binarized image 500 corresponds to the IP-corresponding portion 105a included in the pre-inversion overall image 100a. In the tilt angle identification process, the image processing unit 81 performs principal component analysis using the positions of multiple pixels that constitute the high brightness region 501 included in the generated binarized image 500 as analysis target data, and obtains a first principal component axis for the analysis target data.

[0116] In the principal component analysis, the image processing unit 81 obtains the center of gravity 501a (see FIG. 21) of the high brightness region 501 included in the binarized image 500. Then, as shown in FIG. 21, the image processing unit 81 sets an XY coordinate system with the center of gravity 501a as the origin for the binarized image 500. At this time, the X axis is parallel to the longitudinal direction of the pre-inversion overall image 100a, and the Y axis is parallel to the lateral direction of the pre-inversion 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-inversion overall image 100a and the Y axis is parallel to the lateral direction of the pre-inversion overall image 100a is called the initial orientation.

[0117] When the image processing unit 81 sets the XY coordinate system of the initial posture for the binarized image 500, it calculates the length L of the perpendicular line dropped from the position 510 of each pixel constituting the high-luminance region 501 to the Y-axis. Next, the image processing unit 81 calculates the variance of the multiple lengths L calculated for each of the multiple pixels constituting the high-luminance region 501. This variance is called the variance at the initial posture.

[0118] The image processing unit 81 performs a right-handed process in which the XY coordinate system is rotated from the initial posture to the clockwise 520R by, for example, 0.1 degrees around the center of gravity 501a, and the variance of the multiple lengths L is obtained in the same manner every time the XY coordinate system is rotated by 0.1 degrees. In the right-handed process, the image processing unit 81 finally rotates the XY coordinate system to the clockwise 520R by, for example, 90 degrees. In addition, the image processing unit 81 performs a left-handed process in which the XY coordinate system is rotated from the initial posture to the counterclockwise 520L by, for example, 0.1 degrees around the center of gravity 501a, and the variance of the multiple lengths L is obtained in the same manner every time the XY coordinate system is rotated by 0.1 degrees. In the left-handed process, the image processing unit 81 finally rotates the XY coordinate system to the counterclockwise 520L by, for example, 90 degrees.

[0119] When the image processing unit 81 executes the clockwise and counterclockwise processes, it identifies the minimum value among the multiple variances obtained in the clockwise and counterclockwise processes and the variance at the initial posture. Then, the image processing unit 81 sets the Y axis of the XY coordinate system when the identified minimum value is obtained as the first principal component axis. It can be said that the first principal component axis is an axis that minimizes the variance of the length of the perpendicular line drawn from the positions of the multiple pixels constituting the high brightness region 501 to it. Hereinafter, an axis that is perpendicular to the first principal component axis and passes through the center of gravity 501a may be referred to as the second principal component axis. In addition, the XY coordinate system when the minimum value is obtained among the multiple variances obtained in the clockwise and counterclockwise processes and the variance at the initial posture may be referred to as the XY coordinate system of the minimum variance posture.

[0120] FIG. 22 is a schematic diagram showing the first principal component axis 551 obtained from the binarized image 500 shown in FIG. 21. In FIG. 22, the Y axis of the XY coordinate system of the initial posture is shown by a dashed line. As shown in FIG. 22, the first principal component axis 551 coincides with the longitudinal direction of the high brightness region 501. When the image processing unit 81 obtains the first principal component axis 551, the image processing unit 81 obtains a rotation angle α from the initial posture for an XY coordinate system having a Y axis that coincides with the first principal component axis 551, that is, the XY coordinate system of the minimum variance posture. Then, the image processing unit 81 sets the obtained rotation angle α as the inclination angle α of the longitudinal direction of the IP-corresponding part with respect to the longitudinal direction of the acquired overall image. The Y axis of the XY coordinate system of the initial posture corresponds to the longitudinal direction of the acquired overall 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 longitudinal direction of the IP-corresponding part included in the acquired overall image. Therefore, the rotation angle α can be said to be the inclination angle of the longitudinal direction of the IP-corresponding portion with respect to the longitudinal direction of the acquired overall image. When the XY coordinate system of the minimum variance orientation is obtained by clockwise processing, the rotation angle α indicates a positive value, and when the XY coordinate system of the minimum variance orientation is obtained by counterclockwise processing, the rotation angle α indicates a negative value. When the XY coordinate system of the minimum variance orientation coincides with the XY coordinate system of the initial orientation, the rotation angle α is zero.

[0121] When the image processing unit 81 determines the inclination angle α of the longitudinal direction of the IP-corresponding portion with respect to the longitudinal direction of the acquired overall image from the binarized image 500 of the acquired overall image as described above, the determined inclination angle α is set as the IP inclination angle α. When the imaging plate 10 is viewed in plan from its front side, if the IP inclination angle α is positive, the imaging plate 10 is inclined clockwise with respect to the reference posture, and if the IP inclination angle α is negative, the imaging plate 10 is inclined counterclockwise with respect to the reference posture. Hereinafter, when referring to the inclination of the imaging plate 10, simply "clockwise" means clockwise when the imaging plate 10 is viewed from its front side, and simply "counterclockwise" means counterclockwise when the imaging plate 10 is viewed from its front side.

[0122] The inclination angle specification process as described above may be executed in the series of processes shown in Fig. 18 described above, or may be executed at a timing different from the process shown in Fig. 18. Furthermore, the IP inclination angle determined 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 inclination angle simultaneously with the acquired overall image in, for example, the above-mentioned step s7, or may display the IP inclination angle when the acquired overall image is not displayed.

[0123] Incidentally, instead of performing the above variance calculation every time, a covariance σXY may be calculated in addition to the variances σX2, σY2 in the initial attitude, and used to calculate the variance after rotation.

[0124] Thus, in this example, the image processing unit 81 determines the IP tilt angle based on the image signal as the detection result of the emitted light L2 and reflected light from the imaging plate 10, and therefore can appropriately determine the IP tilt angle.

[0125] For example, consider a case where the sensor 41 cannot detect reflected light and the imaging plate 10 includes an unexposed portion. In this case, the luminance values ​​of the unexposed area image and the IP image outside area image included in the pre-inversion overall image based on the image signal from the sensor 41 are zero. Therefore, in the binarized image 500 obtained by binarizing the pre-inversion overall image, the luminance values ​​of the parts corresponding to the unexposed area image and the IP image outside area image are all "0", and the parts corresponding to the unexposed area image and the IP image outside area image are all low-luminance areas 502. Therefore, when the imaging plate 10 includes an unexposed portion, the high-luminance area 501 of the binarized image 500 does not include a part corresponding to the unexposed portion, and the high-luminance area 501 does not correspond to the IP-corresponding part included in the pre-inversion overall image. In other words, when the imaging plate 10 includes an unexposed portion, the outer shape of the high-luminance area 501 does not correspond to the outer shape of the imaging plate 10. For this reason, when the image processing unit 81 performs principal component analysis on the high-brightness region 501, it may not be able to determine the first principal component axis corresponding to the longitudinal direction of the imaging plate 10, and may not be able to properly determine the inclination angle of the longitudinal direction of the IP-equivalent part relative to the longitudinal direction of the acquired overall image.

[0126] In contrast, in this embodiment, the sensor 41 can detect the reflected light to a certain extent, and the image processor 81 binarizes the pre-inversion overall image based on the image signal as the detection result of the stimulated emission L5 from the imaging plate 10 and the reflected light to generate the binarized image 500. Therefore, in the binarized image 500, even if the imaging plate 10 includes an unexposed portion, the high-luminance region 501 corresponds to the IP-equivalent portion (in other words, the IP image) included in the pre-inversion overall image as shown in Figs. 21 and 22. That is, the outer shape of the high-luminance region 501 corresponds to the outer shape of the imaging plate 10. For example, even from a pre-inversion overall image 100a including an unexposed region image 103a as shown in Fig. 15, a binarized image including the unexposed region in the IP image region can be obtained by binarization processing as shown in Figs. 21 and 22. As a result, when the image processing unit 81 performs a principal component analysis on the high brightness region 501, it can determine the first principal component axis corresponding to the longitudinal direction of the imaging plate 10, and can appropriately determine the inclination angle of the longitudinal direction of the IP corresponding part with respect to the longitudinal direction of the acquired overall image. Therefore, the image processing unit 81 can appropriately specify the IP inclination angle. Note that an image obtained by binarizing an IP image such as the image of the high brightness region 501 may be called an IP binarized image.

[0127] <Identifying the size of the imaging plate> The image processing unit 81 may perform, for example, a size specification process for specifying the size (also referred to as IP size) of the imaging plate 10. In the size specification process, the image processing unit 81 specifies the IP size based on, for example, an image signal output by the detector 40. The image processing unit 81 functions as a specification unit (also referred to as a size specification unit) that specifies the IP size. A specific example of the size specification process will be described below, but the size specification process is not limited to the following example.

[0128] The image processing unit 81, for example, in the same manner as described above, binarizes the pre-inversion overall image based on the pre-inversion image signal to generate a binary image 500. Then, the image processing unit 81 specifies the IP size based on the generated binary image 500. For example, the image processing unit 81 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) numerically.

[0129] When identifying the IP size, the image processing unit 81 performs principal component analysis using the positions of multiple pixels constituting the high brightness region 501 included in the binarized image 500 as analysis target data in the same manner as described above, and obtains a first principal component axis 551 for the analysis target data. 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.

[0130] Fig. 23 is a schematic diagram showing an example of a first principal component axis 551 and a second principal component axis 552. Fig. 23 shows a binarized image 500 obtained by binarizing the pre-inversion overall image 100a shown in Fig. 14 described above, and a first principal component axis 551 and a second principal component axis 552 obtained based on the binarized image 500. The first principal component axis 551 is parallel to the longitudinal direction of a high-luminance region 501 corresponding to the imaging plate 10. The second principal component axis 552 is parallel to the lateral direction of the high-luminance region 501.

[0131] 23, 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 (also referred to as the number of pixels in the transverse direction) N2 along the second principal component axis 552 of the high luminance region 501. Then, the image processing unit 81 obtains the longitudinal size of the imaging plate 10 based on the longitudinal pixel number N1, and obtains the transverse size of the imaging plate 10 based on the transverse pixel number N2.

[0132] Here, in this example, a square area with one side of M mm in the detection range R110 of the sensor 41 corresponds to one pixel of the acquired overall image and the binary image 500. M mm is, for example, about 0.03 mm. The image processing unit 81 determines 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. The image processing unit 81 also determines the length obtained by multiplying M mm by the number of pixels N2 in the lateral direction as the lateral size of the imaging plate 10. Hereinafter, the longitudinal size and lateral size of the imaging plate 10 determined by the image processing unit 81 may be referred to as the specific longitudinal size and the specific lateral size, respectively.

[0133] In the size specification process, the image processing unit 81 may numerically specify 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 determine the value obtained by multiplying the total number of pixels constituting the high luminance region 501 by the square of Mmm as the main surface area of ​​the imaging plate 10. The main surface area may be said to be the area of ​​the front surface of the imaging plate 10, or the area of ​​the back surface of the imaging plate 10. Hereinafter, the main surface area of ​​the imaging plate 10 determined by the image processing unit 81 may be referred to as the specific main surface area or the specific area.

[0134] In the size identification process, the image processing unit 81 may identify the type of size of the imaging plate 10. In this example, a plurality of different sizes are prepared as the size of the imaging plate 10. In the reading device 1, the holding unit 20 is capable of holding each of the imaging plates 10 of the plurality of different sizes. Then, the reading device 1 can read radiation images from each of the imaging plates 10 of the plurality of different sizes.

[0135] 24 is a diagram showing an example of different sizes (also called IP size types) of the imaging plate 10. For example, four types of IP sizes are available: size 0, size 1, size 2, and size 3. Here, the short side size and long side size of the imaging plate 10 for each size type are called the nominal short side size and nominal long side size, respectively. A size commonly adopted by many manufacturers and / or a size determined by a public standard may be adopted as the nominal short side size and nominal long side size.

[0136] For example, according to the ISO (International Organization for Standardization) standard, the nominal short side and long side dimensions of size 0 are 22 mm and 31 mm, respectively. The nominal short side and long side dimensions of size 0 are also 21 mm and 35 mm, respectively. The nominal short side and long side dimensions of size 1 are 24 mm and 40 mm, respectively. The nominal short side and long side dimensions of size 2 are 31 mm and 41 mm, respectively. And the nominal short side and long side dimensions of size 3 are 27 mm and 54 mm, respectively. The value obtained by multiplying the nominal short side and the nominal long side dimensions is called the nominal main surface area or nominal area.

[0137] The image processing unit 81 identifies the size type of the imaging plate 10 based on, for example, the specific short-side size, the specific long-side size, and the specific main surface area of ​​the imaging plate 10. For example, when the specific short-side size is close to the nominal short-side size of size 0, the specific long-side size is close to the nominal long-side size of size 0, and the specific area is close to the nominal area of ​​size 0, the image processing unit 81 determines that the IP size type is size 0.

[0138] The image processing unit 81 determines whether the specific short-side size is close to the nominal short-side size of size 0, for example, using a first threshold value slightly smaller than the nominal short-side size of size 0 and a second threshold value slightly larger than the nominal short-side size of size 0. For example, when the specific short-side 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-side size is close to the nominal short-side size of size 0.

[0139] Furthermore, the image processing unit 81 determines whether or not the specific longitudinal size is close to the nominal longitudinal size of size 0, for example, using a third threshold value that is slightly smaller than the nominal longitudinal size of size 0 and a fourth threshold value that is slightly larger than 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.

[0140] Furthermore, the image processing unit 81 determines whether or not the specific area is close to the nominal area of ​​size 0, for example, using a fifth threshold value slightly smaller than the nominal area of ​​size 0 and a sixth threshold value slightly larger than the nominal area of ​​size 0. For example, when the specific area is larger than the fifth threshold value and smaller than the sixth threshold value, the image processing unit 81 determines that the specific area is close to the nominal area of ​​size 0.

[0141] Similarly, the image processing unit 81 determines that the IP size type is size 1, for example, if the specific short side size is close to the nominal short side size of size 1, the specific long side size is close to the nominal long side size of size 1, and the specific main surface area is close to the nominal main surface area of ​​size 1.

[0142] Similarly, the image processing unit 81 determines that the IP size type is size 2, for example, if the specific short side size is close to the nominal short side size of size 2, the specific long side size is close to the nominal long side size of size 2, and the specific main surface area is close to the nominal main surface area of ​​size 2.

[0143] Similarly, the image processing unit 81 determines that the IP size type is size 3, for example, if the specific short side size is close to the nominal short side size of size 3, the specific long side size is close to the nominal long side size of size 3, and the specific main surface area is close to the nominal main surface area of ​​size 3.

[0144] The size specification process as described above may be executed in the series of processes shown in FIG. 18, or may be executed at a timing different from the process shown in FIG. 18. The display unit 3 may display, for example, at least one of the types of short side size, long side size, main surface area, and IP size specified by the image processing unit 81. In this case, the display unit 3 may display at least one of the types of short side size, long side size, main surface area, and IP size simultaneously with the acquired overall image in, for example, the above-mentioned step s7, or may display them when the acquired overall image is not displayed. The display unit 3 may display at least one of the types of short side size, long side size, main surface area, and IP size simultaneously with the IP inclination angle, or may display them when the IP inclination angle is not displayed. The display unit 3 may display at least two of the types of short side size, long side size, main surface area, and IP size simultaneously.

[0145] Thus, in this example, the image processing unit 81 specifies the IP size based on the image signal as the detection result of the emitted light L2 and reflected light from the imaging plate 10, and therefore can appropriately specify the IP size, similar to the case of specifying the IP inclination angle. As described above, even if the imaging plate 10 includes an unexposed portion, the high-luminance region 501 of the binarized image 500 corresponds to the IP-equivalent portion of the pre-inversion overall image, and therefore the image processing unit 81 can appropriately specify the short-side size, long-side size, and main surface area of ​​the imaging plate 10, and the type of IP size.

[0146] In relation to the explanation of the nominal short side size and the nominal long side size, a setting example of the excitation light irradiation range R120 will be explained. FIG. 25 is a diagram showing each imaging plate 10 of sizes 0 to 3. Here, the positions of the four sides of the imaging plate 10 when the imaging plate 10 is viewed in a plan view are represented by top, bottom, left and right. The holding unit 20 is used commonly for imaging plates 10 of a plurality of sizes, for example. The holding unit 20 holds the imaging plate 10 such that, for example, as shown in FIG. 25, one of the two left and right sides of the imaging plate 10 is located on the same line among the plurality of sizes, and one of the two top and bottom sides of the imaging plate 10 is located on the same line among the plurality of sizes.

[0147] The longitudinal size of the imaging plate 10 of size 3 is larger than the longitudinal size of the imaging plate 10 of size 2, but the transverse size of the imaging plate 10 of size 3 is smaller than the transverse size of the imaging plate 10 of size 2. In order to be compatible with any of the imaging plates 10 of multiple sizes, for example, the excitation light irradiation range R120 is set so that the longitudinal size of the excitation light irradiation range R120 is equal to or larger than the maximum longitudinal size of the multiple IP sizes, and the transverse size of the excitation light irradiation range R120 is equal to or larger than the maximum transverse size of the multiple IP sizes. The excitation light irradiation range R120 set in this manner may be used for any imaging plate 10 of multiple IP sizes, regardless of the IP size of the imaging plate 10.

[0148] Also, the excitation light irradiation range R120 may be changed for each imaging plate 10. In this case, the excitation light irradiation range R120 may be set so that at least the longitudinal size of the excitation light irradiation range R120 is equal to or larger than the maximum longitudinal size of the plurality of IP sizes, and the transverse size of the excitation light irradiation range R120 is equal to or larger than the maximum transverse size of the plurality of IP sizes.

[0149] Fig. 26 is a flowchart showing an example of a series of operations of the image processing unit 81 when the image processing unit 81 specifies the IP inclination angle and the IP size. The series of processes shown in Fig. 26 may be executed in the series of processes shown in Fig. 18 described above, or may be executed at a timing different from the process shown in Fig. 18.

[0150] 26, in step s11, the image processing unit 81 binarizes the pre-inversion overall image based on the pre-inversion image signal to generate a binarized image 500. Next, in step s12, the image processing unit 81 specifies 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 multiple pixels constituting a high brightness region 501 included in the binarized image 500 as analysis target data, and determines a first principal component axis and a second principal component axis for the analysis target data.

[0151] Next, in step s14, the image processing unit 81 identifies the IP tilt angle and the short-side size and long-side 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. Next, in step s15, the image processing unit 81 determines whether the type of IP size is size 3 or not based on the specific short-side size, the specific long-side size, and the specific area. In step s15, the image processing unit 81 determines that the type of IP size is size 3, for example, as described above, when the specific short-side size is close to the nominal short-side size of size 3, the specific long-side size is close to the nominal long-side size of size 3, and the specific area is close to the nominal area of ​​size 3.

[0152] If the determination in step s15 is YES, the process shown in Fig. 26 ends. On the other hand, if the determination in step s15 is NO, 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 short-side size, the specific long-side size, and the specific area. In step s16, the image processing unit 81 determines that the type of IP size is size 2, for example, as described above, when the specific short-side size is close to the nominal short-side size of size 2, the specific long-side size is close to the nominal long-side size of size 2, and the specific area is close to the nominal area of ​​size 2.

[0153] If the determination in step s16 is YES, the process shown in Fig. 26 ends. On the other hand, if the determination in step s16 is NO, 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 short-side size, the specific long-side size, and the specific area. In step s17, the image processing unit 81 determines that the type of IP size is size 1, for example, as described above, if the specific short-side size is close to the nominal short-side size of size 1, the specific long-side size is close to the nominal long-side size of size 1, and the specific area is close to the nominal area of ​​size 1.

[0154] If the determination in step s17 is YES, the process shown in Fig. 26 ends. On the other hand, if the determination in step s17 is NO, step s18 is executed. In step s18, the image processing unit 81 determines that the IP size type is size 0. After execution of step s18, the process shown in Fig. 26 ends. Note that in step s18, the image processing unit 81 may determine whether the IP size type is size 0 or not based on the specific short side size, the specific long side size, and the specific area, similarly to steps s15 to s17.

[0155] In the above example, the image processing unit 81 specifies the type of IP size based on the specific short-side size, the specific long-side size, and the specific area, but it is also possible to specify the type of IP size based on any one of the specific short-side size, the specific long-side size, and the specific area. As shown in FIG. 24, in this example, the nominal short-side size and the nominal long-side size are different from each other among the multiple sizes. Furthermore, the nominal areas are also different from each other among the multiple sizes. The image processing unit 81 may determine the type having the nominal short-side size closest to the specific short-side size among the sizes 0 to 3 as the size type of the imaging plate 10. Furthermore, the image processing unit 81 may determine the type having the nominal long-side size closest to the specific long-side size among the sizes 0 to 3 as the size type of the imaging plate 10. Furthermore, the image processing unit 81 may determine the type having the nominal area closest to the specific area among the sizes 0 to 3 as the size type of the imaging plate 10.

[0156] The image processor 81 may also determine the type of IP size based on any two of the specific short-side size, the specific long-side size, and the specific area. For example, when the specific short-side size is close to the nominal short-side size of size 1 and the specific long-side size is close to the nominal long-side size of size 1, the image processor 81 may determine that the type of IP size is size 1.

[0157] In the size specification process, the longitudinal size of imaging plate 10 does not have to be specified, the lateral size of imaging plate 10 does not have to be specified, and the main surface area of ​​imaging plate 10 does not have to be specified. In addition, in the size specification process, the type of size of imaging plate 10 does not have to be specified.

[0158] The reading device 1 may have a configuration in which the image processing unit 81 specifies the IP size, or instead of the configuration, in which the user can select and specify the IP size. The reading device 1 may also be configured to be able to switch between a configuration in which the image processing unit 81 specifies the IP size and a configuration in which the user selects and specifies the IP size. In this case, for example, a branch is inserted between steps s13 and s14 as to whether or not to accept the user's selection, and if YES, the user's selection is accepted, and then the image processing unit 81 specifies the IP inclination angle but does not specify the IP size.

[0159] <Irradiation of an erased imaging plate with excitation light> In the reading device 1, the light source 30 may irradiate the erased imaging plate 10 with excitation light L10, and the detector 40 may detect reflected light L40 from the erased imaging plate 10 to obtain a reflected light image of the imaging plate 10. In this case, in this example, the detector 40 also detects reflected light L400 from the region R130 outside the IP image region within the irradiation range. In this example, the detector 40 detects the reflected light of the excitation light L10 from the erased imaging plate 10 and the region R130 outside the IP image region within the irradiation range, and outputs an image signal as the detection result. An example of the operation of the reading device 1 that irradiates the erased imaging plate 10 with excitation light L10 will be described below.

[0160] Hereinafter, like the image signals explained so far, an image signal obtained as a result of detection of the stimulated light L5 or the stimulated light L5 and the reflected light (excited region light L20) when the imaging plate 10 for recording a radiation image is held will be referred to as an image signal at the time of emission. Also, like the acquired overall images explained so far, an overall image including a radiation image, that is, an overall image based on an image signal at the time of emission, will be referred to as an overall image at the time of emission. The overall image at the time of emission is an example of an image obtained by radiation imaging in a living body. Also, the above-mentioned overall image before inversion and overall image after inversion will be referred to as an overall image at the time of emission before inversion and an overall image at the time of emission after inversion, respectively.

[0161] In the image signal at light emission, the overall image at light emission, the overall image at light emission before inversion, and the overall image at light emission after inversion, the parts showing the image of the imaging plate 10, i.e., the IP image, may be called the IP image signal at light emission, the IP image at light emission, the IP image at light emission before inversion, and the IP image at light emission after inversion, respectively. The IP image at light emission is an example of an IP biological radiography image. When the imaging plate 10 includes a cone cut, the IP image at light emission is composed of an IP excited region light image and an IP reflected light image (in other words, an IP non-stimulable reflected light image). As in the case of performing step s2, the image signal at light emission may be defined as an image signal as a detection result (biological radiography image acquisition) when the imaging plate 10 held for the purpose of reading a radiation image is irradiated with excitation light L1, i.e., in a reading mode for reading a radiation image. In this case, when the cone cut covers the entire area of ​​the imaging plate 10, the IP image at light emission (IP biological radiography image) is composed of only an IP reflected light image (in other words, an IP non-stimulable reflected light image).

[0162] In addition, an image signal obtained as a result of detection of reflected light of light when the erased imaging plate 10 is held is called an erased image signal. In addition, an entire image based on the erased image signal is called an erased entire image. In this example, the erased entire image includes not only the reflected light image of the imaging plate 10, that is, the reflected light image based on detection of the reflected light L40 of the excitation light L10 at the imaging plate 10, but also the image of the region outside the IP image region, and does not include a radiation image. The erased entire image can also be said to be a reflected light image of the detection range R110 of the sensor 41. The reflected light image of the erased imaging plate 10, that is, the IP reflected light image showing the image of the entire imaging plate 10, may be particularly called an IP entire reflected light image. In addition, hereinafter, the reading device 1 will be described with the entire image based on the image signal output by the detector 40 as a result of light detection as the acquired entire image. In the following description, the acquired entire image is a concept including the light-emitting entire image and the erased entire image.

[0163] Fig. 27 is a flow chart showing an example of the operation of the reading device 1 of this embodiment. When the start button included in the operation unit 4 is operated, the reading device 1 executes the above-mentioned steps s1 to s4, as shown in Fig. 27. In the reading process of step s2, the detector 40 outputs an emitted light image signal as a detection result of the emitted light L2 and the reflected light.

[0164] After the erasure process in step s4, in step s21, the drive unit 50 moves the holder 20 holding the erased imaging plate 10 to the reading start position. Next, step s22 is executed. In step s22, the light source 30 irradiates the front surface of the erased imaging plate 10 and the area outside the IP image area with excitation light L10. Then, the detector 40 detects the reflected light of the excitation light L10 from the front surface of the erased imaging plate 10 and the area outside the IP image area, and outputs an erased image signal as the detection result. The erased image signal is, for example, a grayscale image signal similar to the light-emitted image signal.

[0165] After step s22, the above-mentioned steps s5 and s6 are executed, and the erased imaging plate 10 is discharged to the outlet 2b of the housing 2. Next, in step s27, the display control unit 82 causes the display unit 3 to simultaneously and separately display the entire image at light emission based on the image signal at light emission obtained in step s2, and the entire image at erasure based on the image signal at erasure obtained in step s22. In step s27, the image processing unit 81 displays the entire image at light emission and the entire image at erasure in, for example, grayscale.

[0166] Note that step s27 may be executed any time after step s22. For example, step s27 may be executed between step s22 and step s5. Furthermore, the entire image when light is emitted and the entire image when it is erased do not have to be displayed at the same time. Furthermore, in step s27, the entire image when light is emitted does not have to be displayed. At least one of the size specification process and the tilt angle specification process described above may be executed in the series of processes in FIG. 27, or may be executed at a timing different from the processes in FIG. 27.

[0167] The image signal when erased output by the detector 40 includes the luminance values ​​of a plurality of pixels constituting the IP total reflected light image (in other words, the IP image) and the luminance values ​​of a plurality of pixels constituting the image of the area outside the IP image area. The luminance value included in the image signal when erased 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 luminance of the reflected light image of that certain area included in the image signal when erased increases.

[0168] Fig. 28 is a schematic diagram showing an example of the overall image 200 at the time of erasure. As shown in Fig. 28, the overall image 200 at the time of erasure includes an IP total reflected light image 201 and an IP image area outside area image 202. In the example of Fig. 28, the IP total reflected light image 201 shows the front surface of the imaging plate 10. Since the IP total reflected light image 201 is a portion corresponding to the imaging plate 10 in the overall image 200 at the time of erasure, the IP total reflected light image is also called an IP corresponding portion. The IP total reflected light image 201 is both an IP image and an IP non-photostimulable reflected light image.

[0169] The image processing unit 81 performs image processing on the erasing image signal. In this example, the image processing on the erasing image signal is different from the image processing on the light-emitting image signal, and for example, luminance inversion processing is not performed. Therefore, in the erasing image signal after image processing, similar to the erasing image signal before image processing, when the intensity of reflected light in a certain area of ​​the imaging plate 10 is high, the luminance value of the reflected light image of the certain area becomes large. On the other hand, when the intensity of reflected light in a certain area of ​​the imaging plate 10 is low, the luminance value of the reflected light image of the certain area becomes small. Hereinafter, the erasing overall image 200 based on the erasing image signal subjected to image processing that does not include luminance inversion processing may be referred to as the erasing overall image 200 before inversion.

[0170] In addition, brightness inversion processing may be performed in the image processing for the erased image signal. In this case, the erased overall image based on the erased image signal subjected to image processing including brightness inversion processing may be called the inverted erased overall image. The erased overall image may include both the pre-inverted erased overall image and the post-inverted erased overall image. The post-inverted erased overall image may be used instead of the pre-inverted erased overall image 200.

[0171] The portions showing the image of the imaging plate 10 in the image signal at erasure, the overall image at erasure, the overall image at erasure before inversion, and the overall image at erasure after inversion may be referred to as the IP image signal at erasure, the IP image at erasure, the IP image at erasure before inversion, and the IP image at erasure after inversion, respectively.

[0172] In step s27, the display control unit 82 may, for example, cause the post-inversion light-emission overall image 100b and the pre-inversion erased overall image 200 to be displayed in grayscale on the display unit 3. In this case, the display unit 3 may display the post-inversion light-emission overall image 100b in grayscale as shown in the above-mentioned Figs. 16 and 17, and may display the pre-inversion erased overall image 200 in grayscale as shown in the above-mentioned Fig. 28.

[0173] 29 and 30 are schematic diagrams showing an example of how a post-inversion light-emission overall image 100b and a pre-inversion erase overall image 200 are displayed on the display surface 3a of the display unit 3. Fig. 29 shows the post-inversion light-emission overall image 100b and the pre-inversion erase overall image 200 in the case where the imaging plate 10 does not include an unexposed portion. Fig. 30 shows the post-inversion light-emission overall image 100b and the pre-inversion erase overall image 200 in the case where the imaging plate 10 includes an unexposed portion.

[0174] 29 and 30, the display unit 3 may display the post-inversion light-emission overall image 100b and the pre-inversion erase overall image 200, for example, at the same size or side-by-side. In this example, the display unit 3 displays an image brighter as the luminance value of the image increases, so that in the post-inversion light-emission overall image 100b, for example, the portion in which the teeth are reflected (i.e., the IP excited region light image) and the unexposed region image (in other words, the IP reflected light image or the IP non-stimulable reflected light image) 103b are displayed brightly. Also, in the pre-inversion erase overall image 200, the portion in which the imaging plate 10 is reflected is displayed brightly.

[0175] Preferably, in the display, the position of the outer edge of the radiation image 101b relative to the outer edge of the overall image 100b at the time of inversion light emission corresponds to the position of the outer edge of the IP total reflected light image 201 relative to the outer edge of the overall image 200 at the time of pre-inversion erasure. In this way, the position of the outer edge of the living body radiographic image relative to the outer edge of the living body radiographic image may correspond to the position of the outer edge of the IP imaging plate shape image relative to the outer edge of the imaging plate shape image. By matching the photographing position of the living body radiographic image with the photographing position of the imaging plate shape image, it is easy to arrange them in correspondence in image processing. Even if there is a difference between the two photographing positions, it is possible to arrange them in correspondence in image processing by grasping and calculating the difference.

[0176] In addition, instead of the overall image 200 at pre-inversion erasure displayed alongside the overall image 100b at post-inversion light emission, an image formed by extracting only the IP total reflected light image 201, i.e., an IP imaging plate shape image, may be displayed alongside each other.

[0177] 29 and 30, the pre-inversion erased overall image 200 when the imaging plate 10 includes an unexposed portion is the same as the pre-inversion erased overall image 200 when the imaging plate 10 does not include an unexposed portion. The user can check the appearance of the imaging plate 10 from the pre-inversion erased overall image 200 (in other words, the erased overall image) displayed on the display unit 3. Note that the display method of the post-inversion light-emission overall image 100b and the pre-inversion erased overall image 200 is not limited to the examples shown in FIGS.

[0178] 27, the detector 40 detects excited region light L20 from the imaging plate 10 excited by excitation light L10 from the light source 30, and outputs an image signal at the time of emission as the detection result. Thereafter, after the radiation image is erased from the imaging plate 10, the excitation light L10 is irradiated from the light source 30 onto the erased imaging plate 10, and the detector 40 detects the reflected light of the excitation light L10 from the imaging plate 10. In this way, the reading device 1 can easily obtain both the radiation image recorded on the imaging plate 10 and the reflected light image of the imaging plate 10 by using the same light source 30 and the same detector 40.

[0179] 29 and 30, when the entire image when light is emitted and the entire image when erased are displayed simultaneously and separately, the user can easily compare the entire image when light is emitted with the entire image when erased. In other words, the user can easily compare the radiation image read from the imaging plate 10 with the external appearance of the imaging plate 10. This allows the user to easily identify, for example, that the imaging plate 10 includes an unexposed portion. This point will be described below.

[0180] When the imaging plate 10 includes an unexposed portion, no radiation image is present in the region of the overall image at the time of emission that corresponds to the unexposed portion. However, it is difficult for the user to determine from only the display of the overall image at the time of emission whether a radiation image is originally present in the region and no radiation image is present in the region due to a malfunction of the reading device 1, or whether a radiation image is not present in the region because the imaging plate 10 includes an unexposed portion. In contrast, as in the example of FIG. 30, when the overall image at the time of emission and the overall image at the time of erasure are displayed simultaneously and separately, the user can check the radiation image read from the imaging plate 10 from the display of the overall image at the time of emission, check the appearance of the imaging plate 10 from the display of the overall image at the time of erasure, and compare the two to easily determine that the imaging plate 10 includes an unexposed portion. The user can also easily determine the range of the unexposed portion on the imaging plate 10.

[0181] In the above example, the image processor 81 specifies the IP inclination angle based on the overall image at the time of light emission, but the IP inclination angle may be specified based on the overall image at the time of erasure (in other words, the reflected light image based on the image signal at the time of erasure). Similarly, the image processor 81 may specify the IP size based on the overall image at the time of erasure.

[0182] In addition, the example configuration in which the overall image when light is emitted and the overall image when erased, as in the examples of Figures 29 and 30, are displayed simultaneously and separately, may be modified so that the overall image when erased is replaced with an image such as binary image 500 in Figure 21, and a configuration in which the overall image when light is emitted and an image obtained by binarizing the overall image when light is emitted are displayed simultaneously and separately.

[0183] The image processing unit 81 can identify the IP tilt angle and the IP size based on the entire image at the time of erasure in the same manner as when identifying the IP tilt angle and the IP size based on the entire image at the time of emission. Specifically, for example, the image processing unit 81 binarizes the entire pre-inversion erasure image 200 to generate a binarized image. This binarized image may be referred to as the second binarized image. The binarized image obtained by binarizing the entire pre-inversion erasure image 200 is also an example of the imaging plate-shaped radiation image. The threshold value for binarizing the entire pre-inversion erasure image 200 is set to be larger than the luminance value of the out-of-IP-image region image 202 included in the entire pre-inversion erasure image 200 and smaller than the luminance value of the IP entire reflected light image 201, which is the IP image included in the entire pre-inversion erasure image 200. As a result, the second binarized image becomes the same as the binarized image of the entire pre-inversion emission image. In the second binarized image, the region corresponding to the out-of-IP-image region becomes a low-luminance region, and the region corresponding to the imaging plate 10 becomes a high-luminance region. The outer shape of the high-luminance region of the second binarized image has a shape corresponding to the outer shape of the imaging plate 10 regardless of the exposed / unexposed state of the imaging plate 10 before erasure. Based on the second binarized image, the image processing unit 81 can identify the IP tilt angle, the short-side size, the long-side size, and the main surface area of the imaging plate 10, and the type of the IP size in the same manner as described above. The identification of the IP tilt angle and the IP size is performed by the image processing unit 81 as a specific unit. As a process, after step S27, the same processes as steps S11 to S18 may be performed.

[0184] Thus, even when the erasure-time image signal representing the reflected light image of the imaging plate 10 is used for identifying the IP tilt angle, the IP tilt angle can be appropriately identified in the same manner as when the emission-time image signal is used. Also, even when the erasure-time image signal is used for identifying the IP size, the IP size can be appropriately identified in the same manner as when the emission-time image signal is used.

[0185] <Regarding correction of the tilt of the IP-equivalent portion> When the imaging plate 10 tilts from the reference posture, the IP-equivalent portion (in other words, the IP image) tilts in the acquired overall image, as shown in Fig. 20 and the like. In detail, when the imaging plate 10 tilts clockwise from the reference posture, the longitudinal direction of the IP-equivalent portion tilts clockwise with respect to the direction corresponding to the sub-scanning direction DRs in the acquired overall image (the longitudinal direction of the pre-inversion overall image 100a in Fig. 20). On the other hand, when the imaging plate 10 tilts counterclockwise from the reference posture, the longitudinal direction of the IP-equivalent portion tilts counterclockwise with respect to the direction corresponding to the sub-scanning direction DRs in the acquired overall image. If the acquired overall image is displayed with the IP-equivalent portion tilted, the user may have difficulty viewing the tilted IP-equivalent portion.

[0186] Therefore, the image processing unit 81 may perform a tilt correction process for correcting the tilt of the IP-equivalent portion of the acquired overall image based on the IP tilt angle α determined based on the light-emission overall image or the erased overall image. When the acquired overall image to be corrected is the light-emission overall image based on the detection of the emitted light L2, the tilt correction process corrects the tilt of the IP-equivalent portion, thereby correcting the tilt of the radiation image included in the IP-equivalent portion. On the other hand, when the acquired overall image to be corrected is the erased overall image based on the detection of the reflected light, the tilt correction process corrects the tilt of the IP overall reflected light image in which the imaging plate 10 is reflected. The image processing unit 81 may perform the tilt correction process on the acquired overall image based on the image signal before the luminance inversion process is performed, or may perform the tilt correction process on the acquired overall image based on the image signal after the luminance inversion process is performed. The display unit 3 may display the acquired overall image after the tilt correction process. The tilt correction process may be performed in the series of processes in FIG. 18, or may be performed at a timing different from the process in FIG. 18. The tilt correction process may be executed in the series of processes in Fig. 27, or may be executed at a timing different from the process in Fig. 27. The tilt correction process can be said to be a process for correcting the tilt of the IP-equivalent portion in the acquired overall image (in other words, the IP image) in accordance with the tilt of imaging plate 10 from the reference attitude.

[0187] Fig. 31 is a schematic diagram for explaining an example of the tilt correction process. In Fig. 29, an acquired overall image 250 before the tilt correction process is performed is shown on the upper side, and an acquired overall image 250 after the tilt correction process is performed is shown on the lower side. The acquired overall image 250 to be corrected includes an IP-equivalent portion (in other words, an IP image) 251 and an image of an area outside the IP image area 252. In Fig. 31, the longitudinal direction DR1 of the IP-equivalent portion 251 is shown by a dashed line, and a direction DR2 corresponding to the sub-scanning direction DRs in the acquired overall image 250 is shown by a dashed line.

[0188] In the tilt correction process, the image processing unit 81 obtains the center of gravity 251a of the IP-corresponding portion 251 included in the acquired overall image 250 to be corrected. Here, the center of gravity 251a of the IP-corresponding portion 251 coincides with the center of gravity of the high-luminance region of the binarized image of the acquired overall image 250. The image processing unit 81 generates a binarized image of the acquired overall image 250 and obtains the center of gravity of the high-luminance region of the generated binarized image, thereby making it possible to obtain the center of gravity 251a of the IP-corresponding portion 251 of the acquired overall image 250. Next, the image processing unit 81 rotates the acquired overall image 250 by the IP tilt angle α around the obtained center of gravity 251a. At this time, when the IP tilt angle α is positive, the image processing unit 81 rotates the acquired overall image 250 counterclockwise 255L by the IP tilt angle α, as shown in FIG. 29. On the other hand, when the IP tilt angle α is negative, the image processor 81 rotates the acquired overall image 250 clockwise by the IP tilt angle α. This corrects the tilt of the IP-corresponding portion 251, 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 overall image 250.

[0189] FIG. 32 is a schematic diagram showing an example of a state in which the inclination correction process is performed on the pre-inversion light-emission overall image 100a shown in FIG. 20 described above. As can be understood by comparing FIG. 20 with FIG. 32, the inclination of the radiation image 101a included in the IP-equivalent portion (in other words, IP image) 105a is appropriately corrected by the inclination correction process on the pre-inversion light-emission overall image 100a. The attitude of the IP-equivalent portion 105a in the pre-inversion light-emission overall image 100a after the inclination correction process is the same as the attitude of the IP-equivalent portion 105a in the pre-inversion light-emission overall image 100a obtained when the attitude of the imaging plate 10 is the reference attitude. The display unit 3 may display the pre-inversion light-emission overall image 100a after the inclination correction process in a gray scale as shown in FIG. 32, for example. Hereinafter, displaying the acquired overall image includes displaying the acquired overall image after the inclination correction process.

[0190] In this way, the image processing unit 81 corrects the tilt of the IP-corresponding portion of the acquired overall image based on the IP tilt angle, thereby making it possible to obtain an IP-corresponding portion whose tilt has been appropriately corrected. In this case, the image processing unit 81 functions as a correction processing unit that corrects the tilt of the image of the imaging plate 10 (IP acted light image). For example, when tilt correction processing is performed on the overall image at the time of emission, a radiation image whose tilt has been appropriately corrected can be obtained. Also, when tilt correction processing is performed on the overall image at the time of erasure, an IP total reflected light image whose tilt has been appropriately corrected can be obtained.

[0191] <About the extraction process for the entire captured image> The image processing unit 81 may perform a cutting process in which an image to be cut out from the entire image at the time of light emission including a radiation image is determined based on the IP inclination angle and IP size, and the determined cut out image is cut out from the entire image at the time of light emission. This cutting process makes it possible to obtain a desired cut out image according to the IP inclination angle and IP size from the entire image at the time of light emission. The image processing unit 81 functions as a cutting unit that performs a cutting process. The cutting process may be performed in the series of processes in FIG. 18, or may be performed at a timing different from the processing in FIG. 18. Moreover, the cutting process may be performed in the series of processes in FIG. 27, or may be performed at a timing different from the processing in FIG. 27.

[0192] In the cutout process, for example, an IP-equivalent portion of the entire image when light is emitted (in other words, an IP image) may be determined as the cutout image. In this case, the image processing unit 81 determines the IP-equivalent portion of the entire image when light is emitted as the cutout image based on, for example, the type of IP size and the IP inclination angle specified based on the entire image when light is emitted or the entire image when erased. An example of the operation of the image processing unit 81 when the image processing unit 81 determines the IP-equivalent portion of the entire image when 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 specific size Z. In this example, Z is any one of the values ​​0, 1, 2, and 3.

[0193] In the cut-out process, the image processing unit 81 sets a cut-out frame for the entire image at the time of flashing, for example, based on the type of IP size and the IP tilt angle. Then, the image processing unit 81 determines the part within the cut-out frame in the entire image at the time of flashing as the cut-out image.

[0194] The shape of the cut-out frame is similar to the nominal outer shape of the imaging plate 10 of the specific size Z. In this example, since the outer shape of the imaging plate 10 is a rectangle with rounded corners, the shape of the cut-out frame is also a rectangle with rounded corners. The size of the short side of the cut-out frame corresponds to the nominal short side size of the imaging plate 10 of the specific size Z (also referred to as the nominal short side size of the specific size Z), and the size of the long side of the cut-out frame corresponds to the nominal long side size of the imaging plate 10 of the specific size Z (also referred to as the nominal long side size of the specific size Z).

[0195] Here, the image processing unit 81 knows in advance how many pixels each of the nominal short-side size and the nominal long-side size corresponds to in the acquired overall image for each type of IP size. When P1 pixels correspond to the nominal short-side size of a specific size Z and P2 pixels correspond to the nominal long-side size of a specific size Z, the image processing unit 81 sets the short-side size of the cropping frame to the length of P1 pixels and sets the long-side size of the cropping frame to the length of P2 pixels. For example, when P1=800 and P2=1100, the short-side size of the cropping frame is set to the length of 800 pixels and the long-side size of the cropping frame is set to the length of 1100 pixels.

[0196] When the image processing unit 81 determines the outer shape and size of the cropping frame, it places the cropping frame on the overall image at the time of flashing so that the center of the cropping frame coincides with the center of gravity of the IP-equivalent part of the overall image at the time of flashing and the longitudinal and lateral directions of the cropping frame are parallel to the longitudinal and lateral directions of the overall image at the time of flashing, respectively. Note that, as described above, the center of gravity of the IP-equivalent part of the overall image at the time of flashing coincides with the center of gravity of the high-luminance region of the binarized image of the overall image at the time of flashing.

[0197] Next, the image processing unit 81 rotates the cropping frame arranged on the overall image at the time of light emission by the IP tilt angle around the center of gravity of the IP equivalent part. At this time, the image processing unit 81 rotates the cropping frame clockwise when the IP tilt angle is positive, and rotates the cropping frame counterclockwise when the IP tilt angle is negative. As a result, the part of the overall image at the time of light emission within the cropping frame coincides with the IP equivalent part. The image processing unit 81 determines the part of the overall image at the time of light emission within the cropping frame rotated by the IP tilt angle as the cropped image. Thereafter, the image processing unit 81 crops the determined cropped image from the overall image at the time of light emission. As a result, the IP equivalent part is cropped from the overall image at the time of light emission, and an image of only the part corresponding to the imaging plate 10 can be obtained. The cropping process may be performed on the overall image at the time of light emission before inversion, or may be performed on the overall image at the time of light emission after inversion. In addition, from the purpose of determining the cropping range, it is not necessarily required to apply it to the nominal size, and the imaging plate range obtained as a result of binarization may be applied to the cropping frame.

[0198] FIG. 33 is a schematic diagram showing an example of a state in which a cropping frame 150 is set for the overall image 100b at the time of inversion and light emission shown in FIG. 16 described above. The biological body radiographic image such as the overall image 100b at the time of inversion and light emission to be cropped includes an IP image area and an image of a region outside the IP image area. FIG. 34 is a schematic diagram showing an example of a cropped image 151 within the cropping frame 150 in the overall image 100b at the time of inversion and light emission in the example of FIG. 33, cropped from the overall image 100b at the time of inversion and light emission. As shown in FIG. 34, the IP-equivalent portion 105b is appropriately cropped from the overall image 100b at the time of inversion and light emission. The cropped image 151 includes a radiation image 151a that is the same as the radiation image (in other words, the excited region light image) 101b included in the overall image 100b at the time of inversion and light emission.

[0199] Applying the imaging plate shape data to the radiographic image of the living body so as to cut out the IP-corresponding portion 105b from the post-inversion light-emission overall image 100b is referred to as imaging plate shape application processing. The imaging plate shape application processing includes positioning the imaging plate shape for cutting out the radiographic image of the living body, setting a cutting frame, and extracting the radiographic image of the living body as a cut-out image from the radiographic image of the living body as a result of the cutting out.

[0200] Fig. 35 is a schematic diagram showing an example of how the cutout frame 150 is set for the overall image 100b at the time of inversion and emission shown in Fig. 17 described above. Fig. 36 is a schematic diagram showing an example of how the cutout image 151 within the cutout frame 150 in the overall image 100b at the time of inversion and emission is cut out from the overall image 100b at the time of inversion and emission in the example of Fig. 35. As shown in Fig. 36, even if the overall image 100b at the time of inversion and emission contains an unexposed region image 103b, the IP-corresponding portion 105b is appropriately cut out from the overall image 100b at the time of inversion and emission. The cutout image 151 contains a radiation image 151a that is the same as the radiation image 101b contained in the overall image 100b at the time of inversion and emission, and also contains an unexposed region image 151b that is the same as the unexposed region image (in other words, an IP reflected light image or an IP non-photostimulable reflected light image) 103b contained in the overall image 100b at the time of inversion and emission.

[0201] When the cutout process is performed, the display unit 3 may display the cutout image 151 cut out from the entire image at the time of light emission under the control of the display control unit 82. In this case, the display unit 3 may display the cutout image 151 in gray scale as shown in Figs. 34 and 36. Figs. 34 and 36 can be said to be schematic diagrams showing display examples of the cutout image 151. When the cutout image 151 is displayed, the user can check only the necessary image of the entire image at the time of light emission. When the IP-equivalent part is cut out and displayed as the cutout image 151 from the entire image at the time of light emission as in this example, the user can check only the necessary IP-equivalent part of the entire image at the time of light emission. This allows the user to easily identify that the imaging plate 10 includes an unexposed part by checking the display of the cutout image 151 as shown in Fig. 36, for example. The user can also easily identify the range of the unexposed part on the imaging plate 10.

[0202] The display unit 3 may simultaneously and separately display the cut-out image 151 cut out from the overall image at light emission and the overall image at erasure 200 under the control of the display control unit 82. FIG. 37 is a schematic diagram showing an example of a state in which the cut-out image 151 and the overall image at erasure 200 are displayed in grayscale on the display surface 3a of the display unit 3. FIG. 37 shows the cut-out image 151 including the unexposed region image 151b. As shown in FIG. 37, the display unit 3 may display the cut-out image 151 and the overall image at erasure 200, for example, so that the cut-out image 151 and the IP total reflected light image (in other words, the IP equivalent portion or IP image) 201 of the overall image at erasure 200 are the same size. The display unit 3 may also display the cut-out image 151 and the overall image at erasure 200, for example, side by side. The display unit 3 simultaneously and separately displays the cut-out image 151 and the erased overall image 200, so that the user can easily compare the cut-out image 151 with the erased overall image 200. This allows the user to easily determine whether the IP-corresponding portion has been appropriately cut out from the light-emission overall image by, for example, comparing the IP overall reflected light image 201 included in the erased overall image 200 with the cut-out image 151.

[0203] The cut-out frame 150, i.e., the cut-out range, may be determined based on the erasing overall image 200. In this case, for example, the range of the IP non-stimulable reflected light image (in other words, the IP total reflected light image) in the erasing overall image 200 may be specified by image processing such as boundary processing to determine the cut-out range, and the determined cut-out range may be set in the light-emission overall image to generate the cut-out image 151. At this time, the image processing for the boundary processing may utilize the acquisition of the IP binary image. Positional applications are possible by holding the imaging plate 10 by the holding unit 20 in the same orientation during light emission and erasure.

[0204] The example of the configuration in which an excerpt image and the entire image at the time of erasure, as in the example of Figure 37, are displayed simultaneously and separately, may be modified so that the entire image at the time of erasure is replaced with an image such as binary image 500 in Figure 21, and the excerpt image and an image obtained by binarizing the entire image at the time of light emission are displayed simultaneously and separately.

[0205] Similar to the above-described tilt correction process, the image processing unit 81 may correct the tilt of the cut-out image 151 cut out from the entire image when light is emitted, based on the IP tilt angle specified based on the entire image when light is emitted or the entire image when erased. This makes it easier for the user to see the cut-out image 151 when the corrected cut-out image 151 is displayed, for example. Hereinafter, the tilt correction process is assumed to include correcting the tilt of the cut-out image 151.

[0206] The image processing unit 81 corrects the inclination of the cut-out image 151 in the same manner as the above-mentioned inclination correction process for the entire image at the time of light emission. The image processing unit 81 also functions as a correction processing unit that corrects the inclination of the image of the imaging plate 10 (IP acted light image). Specifically, the image processing unit 81 first obtains the center of gravity of the cut-out image 151. The center of gravity of the cut-out image 151 coincides with the center of gravity of the high brightness area of ​​the binarized image of the entire image at the time of light emission. Therefore, the image processing unit 81 can obtain the center of gravity of the cut-out image 151 by obtaining the center of gravity of the high brightness area of ​​the binarized image of the entire image at the time of light emission. Next, the image processing unit 81 rotates the cut-out image 151 by the IP inclination angle around the obtained center of gravity. At this time, if the IP inclination angle is positive, the image processing unit 81 rotates the cut-out image 151 counterclockwise by the IP inclination angle. On the other hand, when the IP tilt angle is negative, the image processing unit 81 rotates the clipped image 151 clockwise by the IP tilt angle, thereby correcting the tilt of the clipped image 151. Therefore, the tilt of the radiation image based on the light emission image signal and included in the clipped image 151 is corrected.

[0207] 38 to 40 are schematic diagrams showing an example of a state in which the cutting process is performed on the overall image at the time of light emission, and then the inclination correction process is performed on the cut-out image 151. In the example of FIGS. 38 to 40, the cutting process is performed on the overall image at the time of light emission before inversion 100a shown in FIG. 20 described above. As shown in FIG. 38, the image processing unit 81 sets the cutting frame 150 on the overall image at the time of light emission before inversion 100a as described above. Next, the image processing unit 81 cuts out the cut-out image 151 within the cutting frame 150 in the overall image at the time of light emission before inversion 100a from the overall image at the time of light emission before inversion 100a as shown in FIG. 39. Thereafter, as shown in FIG. 40, the image processing unit 81 corrects the inclination of the cut-out image 151 based on the IP inclination angle. Thereby, the inclination of the cut-out image 151 according to the inclination from the reference attitude of the imaging plate 10 is appropriately corrected. The orientation of the cropped image 151 after the tilt has been corrected is the same as the orientation of the cropped image 151 obtained when the orientation of the imaging plate 10 is the reference orientation.

[0208] In the above example, the image processing unit 81 sets the IP-equivalent portion of the entire image at the time of light emission as the cut-out image 151, but it may set a part of the IP-equivalent portion as the cut-out image 151. An example of the operation of the image processing unit 81 in this case will be described below.

[0209] Fig. 41 is a schematic diagram showing another example of the holding unit 20 that holds the imaging plate 10. Fig. 41 shows a state in which each fixing portion 22a of the fixing unit 22 of the holding unit 20 is in the approaching position. In the holding unit 20 (also called holding unit 20A) shown in Fig. 41, when each fixing portion 22a is in the approaching position, the fixing unit 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 approaching position, each fixing portion 22a has an overlapping portion 220a that covers the peripheral portion 10a of the imaging plate 10. The overlapping portion 220 of the fixing unit 22 is composed of the overlapping portions 220a of a plurality of fixing portions 22a.

[0210] When the imaging plate 10 is held by the holding portion 20A, the peripheral portion 10a of the imaging plate 10 is covered by the overlapping portion 220 of the fixing portion 22, and therefore the reader 1 can obtain an entire image at the time of emission that includes the overlapping portion 220. The overlapping portion 220 of the imaging plate 10 may be considered as a gripped portion from the imaging plate 10's perspective.

[0211] FIG. 42 is a schematic diagram showing an example of a pre-inversion light emission overall image 100a obtained when the imaging plate 10 is held by the holding part 20A. The pre-inversion light emission overall image 100a shown in FIG. 42 includes an image 120 (also called an overlapping partial image 120) of the overlapping part 220 of the fixing part 22. The overlapping partial image 120 is an image based on detection of reflected light of the excitation light L10 from the overlapping part 220. The overlapping partial image 120 is composed of an image 120a (also called an overlapping partial image 120a) of the overlapping part 220a of a plurality of fixing parts (also called gripping parts) 22a. In this example, the surface of each fixing part 220a is subjected to, for example, black alumite treatment. Therefore, the luminance value of the overlapping partial image 120 included in the pre-inversion light emission overall image 100a is small. The overlapping partial image 120a is included in the IP image area outside image 102a, and is not included in the radiation image 101a constituting the IP image (IP image area light image).

[0212] When the overlapping partial image 120 is included in the overall image at the time of light emission, the image processing unit 81 may determine a part of the IP-corresponding portion as the cut-out image 151 so that the cut-out image 151 does not include the overlapping partial image 120 (in other words, the multiple overlapping partial images 120a) in the overall image at the time of light emission. In this case, the image processing unit 81 sets the cut-out frame 150 in the overall image at the time of light emission based on the type of IP size and the IP inclination angle, for example, in the same manner as described above. Since the outer shape of the cut-out frame 150 set as described above forms a shape corresponding to the outer shape of the imaging plate 10 (in other words, the outline of the imaging plate 10), at this point in time, the overlapping partial image 120 is included within the cut-out frame 150. FIG. 43 is a schematic diagram showing an example of a state in which the cut-out frame 150 is set as described above for the overall image at the time of light emission 100a before inversion shown in FIG. 42. A plurality of overlapping partial images 120a constituting the overlapping partial image 120 are included within a cropping frame 150 set for the pre-inversion flash overall image 100a.

[0213] The overall image 100a at the time of light emission before inversion shown in FIG. 42 includes an IP image in a state where the fixed portion 22a overlaps the imaging plate 10 (that is, an IP image with a part missing compared to FIG. 32), but the cutout frame 150 according to the outer shape of the imaging plate 10 can be set, for example, as follows. For example, the first principal component axis and the second principal component axis are determined by a method similar to the method described in FIGS. 21 to 23. Although the overlapping partial image 120a is reflected in the IP image, the amount of this reflection is not so large that it interferes with the calculation, so the first principal component axis and the second principal component axis can be determined in the same manner as above. The maximum value of the longitudinal width of the high-luminance region 501 and the maximum value of the lateral width of the high-luminance region 501 are obtained in each of the directions along the first principal component axis and the second principal component axis. Then, the maximum value of the longitudinal width of high-luminance region 501 is set as the longitudinal width of cut-out frame 150, and the maximum value of the lateral width of high-luminance region 501 is set as the lateral width of cut-out frame 150. Alternatively, as described above, when the lateral sizes and longitudinal sizes of imaging plate 10 of a plurality of sizes are stored as nominal lateral sizes and nominal longitudinal sizes, the shape of imaging plate 10 for each size may also be stored, and a cut-out frame may be set according to the shape of imaging plate 10 for each size by checking which size each of the determined maximum values ​​matches.

[0214] After setting the cropping frame 150 to the entire image at the time of emission as described above, the image processing unit 81 reduces the cropping frame 150, for example, in a similar shape so that the overlapping partial images 120 are not included in the cropping frame 150. At this time, the image processing unit 81 reduces the cropping frame 150 in a similar shape so that the overlapping partial images 120 are not included in the cropping frame 150 and the cropping frame 150 after the reduction is as large as possible. The image processing unit 81 can specify the position and range of each overlapping partial image 120a in the entire image at the time of emission, for example, based on the binarized image of the entire image at the time of emission. Then, the image processing unit 81 reduces the cropping frame 150 in a similar shape so that the overlapping partial images 120 are not included in the cropping frame 150 and the cropping frame 150 after the reduction is as large as possible, based on the position and range specified for each overlapping partial image 120a. Then, the image processing unit 81 determines the portion within the reduced cropping frame 150 in the overall image at the time of light emission as the cropped image 151. This results in a cropped image 151 that does not include the overlapping partial image 120 and includes most of the IP corresponding portion 105a. Fig. 44 is a schematic diagram showing an example of a state in which the cropping frame 150 shown in Fig. 43 has been reduced. As shown in Fig. 44, the image processing unit 81 determines the portion within the reduced cropping frame 150 in the pre-inversion flash overall image 100a as the cropped image 151.

[0215] When the image processing unit 81 determines the cut-out image 151, the image processing unit 81 cuts out the cut-out image 151 from the entire image at the time of light emission. Fig. 45 is a schematic diagram showing an example of the state in which the cut-out image 151 shown in Fig. 44 is cut out from the pre-inversion entire image 100a.

[0216] In this way, when the image processing unit 81 determines a part of the IP equivalent part as the cut-out image 151 so that the cut-out image 151 does not include the overlapping partial image 120, it is possible to obtain a cut-out image 151 that does not include the overlapping part 220 of the fixed part 22. As a result, for example, when the cut-out image 151 is displayed, the user is not distracted by the image of the overlapping part 220, and can confirm only the part that leaves as wide an image useful for diagnosis as possible.

[0217] When the surface of the imaging plate 10 facing the radiation image forming layer 11 is viewed in plan, the edges of the surface may be regarded as non-effective areas, and most of the central area of ​​the surface may be regarded as the effective area. For example, in Fig. 44, the area inside the boundary indicated by the cut-out frame 150 may be regarded as the effective area, and the area outside the boundary as the non-effective area. This is because pressure may be applied to the edges (non-effective areas) of the imaging plate 10 during the manufacturing process, and in such cases, it may not be possible to ensure that a good radiation image will be accumulated in the non-effective area. It is also possible to confirm only the image of the effective area by displaying a cut-out image 151 that does not include the overlapping portions 220 of the fixing parts 22.

[0218] Even when the image processor 81 cuts out the cut-out image 151 that does not include the overlapping portion 220 from the entire image at the time of light emission, the image processor 81 may correct the inclination of the cut-out image 151 based on the IP inclination angle as described above. In this case, the display controller 82 may cause the display unit 3 to display the cut-out image 151 whose inclination has been corrected.

[0219] FIG. 46 is a schematic diagram showing another example of the pre-inversion light-emission overall image 100a obtained when the imaging plate 10 is held by the holding unit 20A. FIGS. 47 to 49 are schematic diagrams showing an example of a state in which the pre-inversion light-emission overall image 100a shown in FIG. 46 is subjected to a cutting process, and then a tilt correction process is performed on the cut-out image 151. The image processing unit 81 sets the cutting frame 150 on the pre-inversion light-emission overall image 100a as described above, and then, as shown in FIG. 46, reduces the cutting frame 150 in a similar shape so that the overlapping partial image 120 is not included in the cutting frame 150 and the cut-out frame 150 after reduction is as large as possible. Next, the image processing unit 81 cuts out the cut-out image 151 within the cutting frame 150 in the pre-inversion light-emission overall image 100a from the pre-inversion light-emission overall image 100a as shown in FIG. 48. 49, the image processor 81 corrects the inclination of the extracted image 151 based on the IP inclination angle. This allows the inclination of the extracted image 151 according to the inclination of the imaging plate 10 from the reference posture to be appropriately corrected.

[0220] In this way, the image processor 81 determines at least a part of the IP-equivalent portion of the entire image at the time of light emission as the cut-out image based on the IP size and the IP inclination angle, so that at least a part of the IP-equivalent portion can be appropriately cut out from the entire image at the time of light emission. Note that since the fixed portion 22a is a portion that contacts the edge of the imaging plate 10 in order to fix the imaging plate 10, the overlapping partial image 120 usually exists only at the edge of the entire image. Therefore, the cut-out image may be determined to be an image of the central region with the edge including the overlapping partial image 120 removed.

[0221] Even if the overlapping partial image 120 is not included in the overall image at the time of light emission, the image processing unit 81 may reduce the cropping frame 150 set in the overall image at the time of light emission to, for example, a similar shape, and determine the part within the cropping frame 150 after the reduction in the overall image at the time of light emission as the cropped image 151. Even in this case, a part of the IP-equivalent part (in other words, the IP image) in the overall image at the time of light emission is determined as the cropped image 151. Also, the image processing unit 81 may enlarge the cropping frame 150 set in the overall image at the time of light emission to, for example, a similar shape, and determine the part within the cropping frame 150 after the enlargement in the overall image at the time of light emission as the cropped image 151. In this case, the IP-equivalent part and its surrounding parts (for example, a part of the image of the area outside the IP image area or at least a part of the overlapping partial image 120) are determined as the cropped image 151 in the overall image at the time of light emission.

[0222] In the cutout process, the image processing unit 81 may determine a cutout image (also called a second cutout image) to be cut out in the erased overall image including the IP total reflection light image based on the IP tilt angle and the IP size, and cut out the determined second cutout image from the erased overall image. In this case, the image processing unit 81 may determine at least a part of the IP-equivalent part (in other words, the IP total reflection light image) of the erased overall image as the second cutout image. In addition, when the erased overall image includes an image of the overlapping part 220, the image processing unit 81 may determine the second cutout image so that the second cutout image does not include the image of the overlapping part 220. In addition, the display control unit 82 may display the second cutout image cut out from the erased overall image on the display unit 3. In this case, the display unit 3 may simultaneously and separately display the second cutout image and the cutout image (also called a first cutout image) 151 cut out from the light-emitting overall image. Furthermore, the image processing unit 81 may correct the tilt of the extracted second clipped image based on the IP tilt angle. Furthermore, the display control unit 82 may cause the display unit 3 to display the second clipped image whose tilt has been corrected. In this case, the display unit 3 may simultaneously and separately display the second clipped image whose tilt has been corrected and the first clipped image whose tilt has been corrected.

[0223] In addition, when the imaging plate 10 is hardly tilted from the reference posture, the image processing unit 81 may determine the first and second cropped images based on the IP size without using the IP tilt angle. In this case, the cropping process does not require a process of rotating the cropping frame according to the IP tilt angle. Hereinafter, displaying a cropped image includes displaying a cropped image whose tilt has been corrected.

[0224] As described above, the image processor 81 sets a cutout range for cutting out the IP living body radiographic image, which is an image based on the detection of the IP interacted light, from the living body radiographic image. This makes it possible to appropriately cut out the image of the portion of the living body radiographic image that corresponds to the imaging plate.

[0225] <Identification of unexposed area images> The image processing unit 81 may perform an unexposed region identification process for identifying an unexposed region image in the first cut-out image 151 or an unexposed region image in the entire image at the time of light emission. The unexposed region identification process may be executed in the series of processes in FIG. 18, or may be executed at a timing different from the processes in FIG. 18. The unexposed region identification process may be executed in the series of processes in FIG. 27, or may be executed at a timing different from the processes in FIG. 27. The image processing unit 81 functions as an identification unit (also called an unexposed region image identification unit) that identifies an unexposed region image. Identification of the unexposed region image makes it easy to identify how much of a living body image region is present in an acquired image obtained by radiography of a living body.

[0226] When the image processing unit 81 sets at least a part of the IP corresponding portion to the first cropped image 151 as in the examples of Figures 39 and 45, for example, in the unexposed identification process, it generates a binary image obtained by binarizing the first cropped image 151. Here, as in the above-mentioned Figures 34 and 36, the first cropped image 151 cropped from the post-inversion light-emission overall image 100b is called the post-inversion first cropped image 151. Also, as in the above-mentioned Figures 45 and 48, the first cropped image 151 cropped from the pre-inversion light-emission overall image 100a is called the pre-inversion first cropped image 151.

[0227] The threshold value used for binarizing the first cut-out image 151 before inversion is set to a value that is, for example, smaller than the minimum luminance value of the radiation image included in the first cut-out image 151 before inversion and larger than the luminance value of the unexposed area image included in the first cut-out image 151 before inversion. For example, consider a case where the minimum luminance value of the radiation image included in the first cut-out image 151 before inversion is IL4 and the luminance value of the unexposed area image included in the first cut-out image 151 before inversion is IL2. Since IL2 < IL4. In this case, the threshold value is set to IL50 such that, for example, IL2 < IL5 < IL4. As a result, in the binarized image of the first cut-out image 151 which is at least a part of the IP equivalent part, the part corresponding to the unexposed area image becomes a low luminance area and the part corresponding to the radiation image becomes a high luminance area. The image processing unit 81 can appropriately identify the unexposed area image in the first cut-out image 151 by identifying the low luminance area in the binarized image of the first cut-out image 151. Note that when the imaging plate 10 does not include an unexposed portion, the binarized image of the first cut-out image 151 does not include a low luminance area.

[0228] Also, the threshold value used for binarizing the first cut-out image 151 after inversion is set to a value that is, for example, larger than the maximum luminance value of the radiation image included in the first cut-out image 151 after inversion and smaller than the luminance value of the unexposed area image included in the first cut-out image 151 after inversion. As a result, in the binarized image of the first cut-out image 151 which is at least a part of the IP equivalent part, the part corresponding to the unexposed area image becomes a high luminance area and the part corresponding to the radiation image becomes a low luminance area. The image processing unit 81 can appropriately identify the unexposed area image in the first cut-out image 151 after inversion by identifying the high luminance area in the binarized image of the first cut-out image 151 after inversion.

[0229] In this way, when the image processing unit 81 cuts out at least a part of the IP equivalent part from the entire image during emission as the first cut-out image 151, the image processing unit 81 can appropriately identify the unexposed area image in the first cut-out image 151.

[0230] In the unexposed region identification process, the image processing unit 81 may identify an unexposed region image in the first clipped image 151 including the IP image region outside region image. In this case, the image processing unit 81 may identify an unexposed region image in the first clipped image 151 including the first clipped image 151 included in the IP image region outside region image. When identifying an unexposed region image in the first clipped image 151 including the IP image region outside region image, the image processing unit 81 ternarizes the first clipped image 151 to generate a ternarized image.

[0231] The image processing unit 81 first compares the luminance values ​​of each of the pixels constituting the first cut-out image 151 with a lower threshold value and an upper threshold value that are set in advance. The upper threshold value is a value larger than the lower threshold value. The image processing unit 81 replaces the luminance values ​​of each of the pixels constituting the first cut-out image 151 that are less than the lower threshold value with a first value, replaces the luminance values ​​that are equal to or greater than the lower threshold value and less than the upper threshold value with a second value, and replaces the luminance values ​​that are equal to or greater than the upper threshold value with a third value. Here, the third value is larger than the second value, and the second value is larger than the first value. This results in the first cut-out image 151 being ternarized to obtain a ternarized image. Hereinafter, in the ternarized image, a region where the luminance value is the third value may be referred to as a high luminance region, a region where the luminance value is the second value may be referred to as a medium luminance region, and a region where the luminance value is the first value may be referred to as a low luminance region.

[0232] A lower threshold value (also referred to as a first threshold value) used in the ternary conversion of the first pre-inversion cropped image 151 is set to, for example, a value greater than the luminance value of the IP image area outside region image included in the first pre-inversion cropped image 151 and less than the luminance value of the unexposed region image included in the first pre-inversion cropped image 151. An upper threshold value (also referred to as a second threshold value) used in the ternary conversion of the first pre-inversion cropped image 151 is set to, for example, a value greater than the luminance value of the unexposed region image included in the first pre-inversion cropped image 151 and less than the minimum luminance value of the radiation image included in the first pre-inversion cropped image 151. For example, consider a case where the minimum luminance value of the radiation image included in the first pre-inversion cropped image 151 is 10,000, the luminance value of the unexposed region image included in the first pre-inversion cropped image 151 is 3,000, and the luminance value of the IP image area outside region image included in the first pre-inversion cropped image 151 is 1,000. In this case, the lower threshold is set to, for example, 2000, and the upper threshold is set to, for example, 5000. As a result, in the ternary image of the first pre-inversion cut-out image 151, the portion corresponding to the IP image outside region image becomes a low-luminance region, the portion corresponding to the unexposed region image becomes a medium-luminance region, and the portion corresponding to the radiation image becomes a high-luminance region. The image processing unit 81 can appropriately specify the unexposed region image in the first pre-inversion cut-out image 151 by specifying the medium-luminance region in the ternary image of the first pre-inversion cut-out image 151. Note that if the imaging plate 10 does not include an unexposed portion, the ternary image of the first pre-inversion cut-out image 151 does not include a medium-luminance region.

[0233] A lower threshold value (also referred to as a first threshold value) used in the ternary conversion of the inverted first cut-out image 151 is set to, for example, a value greater than the maximum luminance value of the radiation image contained in the inverted first cut-out image 151 and less than the luminance value of the unexposed region image contained in the inverted first cut-out image 151. An upper threshold value (also referred to as a second threshold value) used in the ternary conversion of the inverted first cut-out image 151 is set to, for example, a value greater than the luminance value of the unexposed region image contained in the inverted first cut-out image 151 and less than the luminance value of the IP image region outside region image contained in the inverted first cut-out image 151. As a result, in the ternary conversion image of the inverted first cut-out image 151, a portion corresponding to the IP image region outside region image becomes a high luminance region, a portion corresponding to the unexposed region image becomes a medium luminance region, and a portion corresponding to the radiation image becomes a low luminance region. The image processing unit 81 can appropriately specify the unexposed region image in the inverted first clipped image 151 by specifying the medium luminance region in the ternary image of the inverted first clipped image 151 .

[0234] In this way, the image processing unit 81 can appropriately identify the unexposed area image in the first clipped image 151 including the IP image area outside area image.

[0235] In the unexposed area specification process, the image processing unit 81 may specify an unexposed area image in the overall image at the time of light emission. In this case, the image processing unit 81 ternarizes the overall image at the time of light emission to generate a ternarized image in the same manner as in the case of specifying an unexposed area image in the first cut-out image 151 including an area image outside the IP image area. The lower threshold value and the upper threshold value used in the ternarization of the overall image at the time of light emission before inversion 100a are set in the same manner as the lower threshold value and the upper threshold value used in the ternarization of the first cut-out image 151 before inversion. The image processing unit 81 can appropriately specify an unexposed area image in the overall image at the time of light emission before inversion 100a by specifying a medium luminance area in the ternarized image of the overall image at the time of light emission before inversion 100a. In addition, the lower threshold value and the upper threshold value used in the ternarization of the overall image at the time of light emission after inversion 100b are set in the same manner as the lower threshold value and the upper threshold value used in the ternarization of the first cut-out image 151 after inversion. The image processing unit 81 can appropriately specify the unexposed region image in the post-inversion flash overall image 100b by specifying the medium luminance region in the ternary image of the post-inversion flash overall image 100b.

[0236] When the image processing unit 81 identifies an unexposed region image in the first clipped image 151 or the overall image at the time of light emission, the display control unit 82 may cause the display unit 3 to display unexposed notification information 161 notifying that an unexposed region image exists in the first clipped image 151 or the overall image at the time of light emission. This allows the user to easily recognize that an unexposed region image exists in the first clipped image 151 or the overall image at the time of light emission. Therefore, the user can easily recognize that the imaging plate 10 includes an unexposed portion.

[0237] 50 and 51 are schematic diagrams showing display examples of the unexposed notification information 161. In the example of FIG. 50, the first cut-out image 151 including the radiation image 151a and the unexposed region image 151b and the unexposed notification information 161 are displayed on the display surface 3a of the display unit 3. In the example of FIG. 51, the whole image 100b at the time of inversion and the unexposed notification information 161 are displayed on the display surface 3a. In the example of FIG. 50, a border line 1510 bordering the range of the unexposed region image 151b is displayed as the unexposed notification information 161 notifying that the unexposed region image 151b exists in the first cut-out image 151. Similarly, in the example of FIG. 51, a border line 1030 bordering the range of the unexposed region image 103b is displayed as the unexposed notification information 161 notifying that the unexposed region image 103b exists in the whole image 100b at the time of inversion and the light emission. The borders 1510 and 1030 may be displayed in at least one color.

[0238] The unexposed notification information 161 is not limited to the examples in Figures 50 and 51. For example, hatching such as diagonal lines applied to the unexposed area image may be displayed as the unexposed notification information 161. Furthermore, the unexposed area image may be displayed in at least one color to display the unexposed notification information 161.

[0239] Also, as shown in FIG. 52, a frame-shaped figure 1511 surrounding the first cut-out image 151 may be displayed as the unexposed notification information 161. In the example of FIG. 52, for convenience of explanation, hatching is shown in the frame-shaped figure 1511, but the frame-shaped figure 1511 may not be hatched or may be hatched. Also, the frame-shaped figure 1511 may be displayed in color with at least one color. Similarly, when an unexposed region image is specified in the overall image at the time of flashing, a frame-shaped figure surrounding the overall image at the time of flashing may be displayed as the unexposed notification information 161. Also, the unexposed notification information 161 may be displayed as at least one of a character and a symbol.

[0240] If the first cropped image 151 or the overall image at the time of light emission does not include an unexposed region image, that is, if the image processing unit 81 does not identify an unexposed region image in the first cropped image 151 or the overall image at the time of light emission, the display control unit 82 may cause the display unit 3 to display notification information 162 notifying that an unexposed region image does not exist in the first cropped image 151 or the overall image at the time of light emission. This allows the user to easily recognize that the imaging plate 10 does not include an unexposed portion.

[0241] FIG. 53 is a schematic diagram showing a display example of the notification information 162. FIG. 53 shows a display example of the notification information 162 notifying that the first cut-out image 151 does not include an unexposed region image. In the example of FIG. 53, a frame-shaped figure 1512 surrounding the first cut-out image 151 not including an unexposed region image is displayed as the notification information 162. In the example of FIG. 53, hatching is shown on the frame-shaped figure 1512 for convenience of explanation, but hatching may not be shown on the frame-shaped figure 1512 or may be shown on the frame-shaped figure 1512. In addition, the frame-shaped figure 1512 may be displayed in at least one color. When the frame-shaped figure 1511 of FIG. 52 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 displayed in different modes from each other. At this time, the frame-shaped figure 1511 and the frame-shaped figure 1512 may be displayed in different colors from each other. Also, the frame-shaped graphic 1511 and the frame-shaped graphic 1512 may be shown with different hatching. Similarly, when an unexposed region image does not exist in the overall image at the time of flashing, a frame-shaped graphic surrounding the overall image at the time of flashing may be displayed as notification information 162. Also, the notification information 162 may be displayed as at least one of characters and symbols. Note that if an unexposed region image exists, the presence of the unexposed region image is notified in a display mode different from that of the frame-shaped graphic 1512, so it can be said that the absence of an unexposed region image is notified by notifying the presence of the unexposed region image.

[0242] As shown in FIG. 37, when the display control unit 82 simultaneously and separately displays the first cut-out image 151 and the entire image at erasure 200 on the display unit 3, and when the first cut-out image 151 includes an unexposed region image, the display control unit 82 may also display the unexposed notification information 161 on the display unit 3 as shown in FIG. 54. At this time, the second cut-out image may be displayed instead of the entire image at erasure 200. Also, as shown in FIG. 30, when the display control unit 82 simultaneously and separately displays the entire image at light emission and the entire image at erasure 200 on the display unit 3, and when the entire image at light emission includes an unexposed region image, the display control unit 82 may also display the unexposed notification information 161 on the display unit 3 as shown in FIG. 55. At this time, the second cut-out image may be displayed instead of the entire image at erasure 200.

[0243] Furthermore, when the display control unit 82 causes the display unit 3 to simultaneously and separately display the first cut-out image 151 not including an unexposed region image and the overall image at erasure 200, the display control unit 82 may also cause the display unit 3 to display the notification information 162 together. At this time, the second cut-out image may be displayed instead of the overall image at erasure 200. Similarly, when the display control unit 82 causes the display unit 3 to simultaneously and separately display the overall image at light emission not including an unexposed region image and the overall image at erasure 200, the display control unit 82 may also cause the display unit 3 to display the notification information 162 together. At this time, the second cut-out image may be displayed instead of the overall image at erasure 200.

[0244] 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 L10 from the imaging plate 10 to a certain extent. Therefore, the reading device 1 can obtain a radiation image based on the detection of the emitted light L2, and a reflected light image (such as an image of an unexposed area) based on the detection of the reflected light. This improves the convenience of the reading device 1.

[0245] For example, the reading device 1 can appropriately determine the IP size and the IP inclination angle as described above based on the overall image at the time of emission, which includes a radiation 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.

[0246] 29, 30, 37, 54, 55, etc., the reading device 1 simultaneously and separately displays a radiation image based on detection of emitted light L2 from the imaging plate 10 and a reflected light image based on detection of reflected light from the imaging plate 10, thereby allowing the user to easily compare the radiation image read from the imaging plate 10 with the appearance of the imaging plate 10. This allows the user to easily identify, for example, that the imaging plate 10 includes an unexposed portion.

[0247] 28 to 30, 54, 55, etc., when an IP total reflected light image, which is a reflected light image based on detection of reflected light from the imaging plate 10, is displayed, the user can easily identify, for example, whether or not an abnormality has occurred on the surface of the imaging plate 10. Abnormalities on the surface of the imaging plate 10 include, for example, scratches, dents, chips, dirt, and the attachment of foreign matter.

[0248] 56 and 57 are schematic diagrams showing an example of a radiation image 101b included in the post-inversion light emission overall image 100b acquired by the reader 1 when an abnormality occurs on the front surface of the imaging plate 10, and an example of an IP total reflection light image 201 included in the pre-inversion erase overall image 200 acquired by the reader 1, respectively. In the illustrated example, the pre-inversion erase overall image 200 is used as the erase overall image. FIG. 56 also shows an enlarged view 1010L of an abnormal area image 1010 in which an abnormality on the surface of the imaging plate 10 is reflected in the radiation image 101b. FIG. 57 also shows an enlarged view 2010L of an abnormal area image 2010 in which an abnormality on the surface of the imaging plate 10 is reflected in the IP total reflection light image 201. FIGS. 56 and 57 show the radiation image 101b and the IP total reflection light image 201, respectively, when a scratch occurs on the front surface of the imaging plate 10.

[0249] As shown in Figures 56 and 57, in the radiation image 101b and the IP total reflected light image 201, the luminance value of the abnormal area image 1010 showing an abnormality on the surface of the imaging plate 10 may differ from the luminance value of its surroundings. On the other hand, even if a lesion such as caries occurs in the tooth being imaged, the luminance value of the area showing the lesion site on the tooth in the radiation image 101b may differ from the luminance value of its surroundings. Furthermore, unlike the example of Figure 56, in the radiation image 101b, the luminance value of the abnormal area image 1010 may be close to the luminance value of the area showing the tooth. In view of these points, it is not easy for a user to identify an abnormality on the surface of the imaging plate 10 based on the radiation image 101b displayed on the display unit 3.

[0250] In contrast, teeth are not reflected in the IP total reflected light image 201 of the imaging plate 10 that does not accumulate a radiation image as a latent image. Therefore, the user can easily identify an abnormality on the surface of the imaging plate 10 based on the IP total reflected light image 201 displayed on the display unit 3. That is, the user can easily identify an abnormality on the surface of the imaging plate 10 by recognizing the abnormal area image 1010 included in the IP total reflected light image 201 displayed on the display unit 3. The user may identify an abnormality on the surface of the imaging plate 10 based on the erased overall image 200 including the IP total reflected light image 201 displayed on the display unit 3. The user may also identify an abnormality on the surface of the imaging plate 10 based on a second cut-out image including at least a part of the IP total reflected light image 201 displayed on the display unit 3.

[0251] When the display unit 3 simultaneously and separately displays the radiation image and the IP total reflected light image, the user can easily identify an area in the radiation image that corresponds to an abnormality on the surface of the imaging plate 10. Therefore, for example, if the user is a dentist, the dentist can easily exclude an area in the radiation image that corresponds to an abnormality on the surface of the imaging plate 10 from information for diagnosis.

[0252] FIG. 58 is a schematic diagram showing a display example of the first cut-out image 151 and the second cut-out image 152 acquired for the imaging plate 10 having an abnormality on the front surface. In the example of FIG. 58, the IP-corresponding portion 105b of the post-inversion light emission overall image 100b is set as the first cut-out image 151, and the erased IP reflected light image (i.e., the IP-corresponding portion) 201 of the pre-inversion erased overall image 200 is set as the second cut-out image 152. The second cut-out image 152 has an abnormal area image 2010 in which an abnormality on the surface of the imaging plate 10 is captured. When the display as shown in FIG. 58 is performed, the user specifies the abnormal area image 2010 in the erased IP reflected light image 201 included in the displayed second cut-out image 152, for example. Then, the user specifies an area corresponding to the abnormality of the imaging plate 10 in the radiation image 101b included in the first cut-out image 151 based on the abnormal area image 2010 specified in the erased IP reflected light image 201.

[0253] The display control unit 82 may simultaneously and separately display the IP total reflection light images of the multiple imaging plates 10 on the display unit 3. FIG. 59 is a schematic diagram showing an example of such a display. In the example of FIG. 59, multiple second cut-out images 152, each of which shows the front surface of the multiple imaging plates 10, are displayed on the display surface 3a. In the example of FIG. 59, the IP total reflection light image 201 of the pre-reversal erasure overall image 200 is set as the second cut-out image 152. As shown in FIG. 59, multiple IP total reflection light images 201, each of which shows the front surface of the multiple imaging plates 10, are simultaneously and separately displayed, so that the user can easily identify, for example, an imaging plate 10 in which an abnormality occurs over a relatively wide range among the multiple imaging plates 10. The user may, for example, discard the imaging plate 10 in which an abnormality occurs over a wide range. In addition, multiple erasure overall images, each of which shows the front surface of the multiple imaging plates 10, may be simultaneously and separately displayed on the display unit 3.

[0254] When the operation unit 4 accepts a predetermined operation from the user, the display control unit 82 may display a plurality of IP total reflection light images 201 acquired in the past on the display unit 3 as shown in FIG. 59. When the operation unit 4 accepts a predetermined operation from the user, the reading device 1 may set the operation mode of the reading device 1 to a quality confirmation mode for confirming the quality of the imaging plate 10, and in this quality confirmation mode, a plurality of IP total reflection light images 201 each showing a plurality of imaging plates 10 may be acquired and displayed as shown in FIG. 59. A plurality of imaging plates 10 are sequentially inserted into the reading device 1 in the quality confirmation mode by the user. When one imaging plate 10 is inserted through the insertion port 2a, the reading device 1 in the quality confirmation mode executes, for example, steps s3, s4, s21, and s22 in FIG. 27 described above to acquire an erased overall image showing the front surface of the inserted imaging plate 10. Then, the reading device 1 executes steps s5 and s6 in FIG. 27 to eject the processed imaging plate 10. When the processed imaging plate 10 is discharged from the reading device 1, the next imaging plate 10 is inserted into the reading device 1. The reading device 1 in the quality confirmation mode operates in the same way to obtain an erased overall image showing the front of the next imaging plate 10, and discharges the processed imaging plate 10. Thereafter, the loading of imaging plates 10 into the reading device 1 and the discharge of imaging plates 10 from the reading device 1 are repeated in the same way, and the reading device 1 in the quality confirmation mode obtains a plurality of erased overall images showing a plurality of imaging plates 10 respectively. Thereafter, the display control unit 82 causes the display unit 3 to display as shown in FIG. 59 based on the obtained plurality of erased overall images. For example, the user identifies and discards an imaging plate 10 in which a wide range of abnormalities have occurred based on the display of FIG. 59.

[0255] Furthermore, when the IP total reflected light image is displayed, the user can specify, for example, that the imaging plate 10 has been inserted into the reading device 1 face down, which is the opposite of normal, and set upside down, based on the display of the IP total reflected light image. In this example, the user inserts the imaging plate 10 into the reading device 1 face up as a rule, but it is possible to insert it upside down by mistake. When the imaging plate 10 is inserted face up and set correctly, the support plate 21 of the holding part 20 supports the back surface of the imaging plate 10 as described above. Therefore, the excitation light L10 is correctly irradiated onto the radiation image forming layer 11 of the imaging plate 10 as described above. On the other hand, when the imaging plate 10 is mistakenly inserted face down and set upside down, the support plate 21 supports the front surface of the imaging plate 10, that is, the radiation image forming layer 11 of the imaging plate 10. Therefore, the excitation light L10 is irradiated onto the back surface of the imaging plate 10. The detector 40 detects the reflected light of the excitation light L10 from the rear surface of the imaging plate 10 and from the area R130 outside the IP image area, and outputs an image signal as the detection result.

[0256] Hereinafter, the image signal resulting from the detection of reflected light when the imaging plate 10 is inserted face down into the reading device 1 and set upside down will be referred to as the image signal when the imaging plate is inserted face down. Also, the overall image based on the image signal when the imaging plate is inserted face down will be referred to as the overall image when the imaging plate is inserted face down. The overall image when the imaging plate is inserted face down does not include a radiation image, but includes, for example, an IP overall reflected light image showing the back surface of the imaging plate 10 and an image of an area outside the IP image area. Also, the support plate 21 supporting the front surface of the imaging plate 10 will be referred to as front support, and the support plate 21 supporting the back surface of the imaging plate 10 will be referred to as back support.

[0257] In the above description, it is assumed that the imaging plate 10 is always inserted in the reading device 1 facing up and set correctly. In other words, in the above description, it is assumed that the imaging plate 10 is always supported on the back side. Therefore, in the above description of the process in FIG. 14, the light-emission overall image including the radiation image is obtained in step s2, and the light-emission overall image including the radiation image is displayed in step s7. However, when the imaging plate 10 is inserted in the reading device 1 facing down, the acquired overall image obtained in step s2, in other words, the overall image based on the image signal output by the detector 40 in step s2, is a back-insertion overall image in which the back side of the imaging plate 10 is reflected. In other words, in step s2, a back-insertion overall image not including a radiation image is obtained, not a light-emission overall image including a radiation image. Therefore, when the imaging plate 10 is inserted in the reading device 1 facing down, a back-insertion overall image is displayed in step s7. In the reading process in step s2, if the imaging plate 10 is set correctly, a radiation image is read from the imaging plate 10, and if the imaging plate 10 is set upside down, an overall image of the imaging plate 10 inserted backwards, showing the back side of the imaging plate 10, is obtained.

[0258] 24, a rear-insertion overall image is obtained in step s2, and an erased overall image obtained in step s22 is a rear-insertion overall image. Therefore, when the imaging plate 10 is inserted face-down in the reading device 1, two rear-insertion overall images are displayed in step s27. Neither the rear-insertion overall image showing the back side of the imaging plate 10 nor the erased overall image obtained when the erased imaging plate 10 is held by the holding unit 20 includes a radiation image, and is composed only of a reflected light image.

[0259] FIG. 60 is a schematic diagram showing an example of an IP total reflected light image 301 included in the overall image when the imaging plate 10 is inserted backward. In this example, information specific to the back side of the imaging plate 10 (also referred to as back side specific information) is shown on the back side of the imaging plate 10. The back side specific information can also be said to be information that is not shown on the front side of the imaging plate 10. The back side specific information can also be said to be back side identification information or back side identifier for identifying the back side of the imaging plate 10. The back side specific information includes, for example, characters indicating the size type of the imaging plate 10, characters and a barcode indicating the manufacturer of the imaging plate 10, and the like. The barcode included in the back side specific information may indicate, for example, the serial number of the imaging plate 10.

[0260] 60, an IP total reflected light image 301 showing the back surface of the imaging plate 10 includes an image 302 of back surface specific information. The image 302 includes an image 304 of characters indicating the size type of the imaging plate 10, an image 305 of characters indicating the manufacturer of the imaging plate 10, and an image 303 of a barcode.

[0261] When the display unit 3 displays the overall image when the imaging plate 10 is inserted face down, the user can determine that the imaging plate 10 has been inserted face down into the reading device 1, that is, that the imaging plate 10 has been set upside down, based on the IP total reflected light image 301 included in the displayed overall image when the imaging plate 10 is inserted face down. Specifically, the user can determine that the imaging plate 10 has been inserted face down into the reading device 1 by recognizing the image 302 of the back-side specific information included in the displayed IP total reflected light image 301. In this way, the user can recognize that the imaging plate 10 has not been inserted correctly into the reading device 1.

[0262] From another perspective, the user can determine that the imaging plate 10 has been correctly inserted into the reading device 1 with the front side facing up, i.e., that the imaging plate 10 has been set correctly, by recognizing that the IP total reflected light image displayed on the display unit 3 does not include an image of the back-side specific information.

[0263] The back-side unique information shown on the back side of imaging plate 10 is not limited to the above. For example, the back-side unique information may include a two-dimensional barcode. The back-side unique information may also include letters, symbols, or figures shown on at least one of the four corners of the back side of imaging plate 10. The back-side unique information may also be the minimum information necessary to identify the back side of imaging plate 10.

[0264] The image processing unit 81 may cut out at least a part of the IP total reflected light image 301 as a cut-out image from the overall image at the time of insertion backside, in the same manner as when cutting out the second cut-out image including at least a part of the IP total reflected light image from the overall image at the time of erasing. In this case, the display control unit 82 may display at least a part of the IP total reflected light image 301 cut out from the overall image at the time of insertion backside on the display unit 3. This allows the user to identify that the imaging plate 10 has been erroneously inserted face down into the reading device 1, based on at least a part of the displayed IP total reflected light image 301.

[0265] In the above example, the back-side specific information shown on the back side of the imaging plate 10 is used to enable the user to identify that the imaging plate 10 has been placed face down in the reading device 1, but information specific to the front side (also called front side specific information) shown on the front side of the imaging plate 10 may also be used. The front side specific information can also be said to be information that is not shown on the back side of the imaging plate 10. The front side specific information can also be said to be front side identification information or a front side identifier for identifying the front side of the imaging plate 10.

[0266] Fig. 61 is a schematic diagram showing an example of an imaging plate 10 in which front surface unique information 1000 is indicated on the front surface 10x. As shown in Fig. 61, the front surface unique information 1000 may include characters. The characters included in the front surface unique information 1000 may be characters indicating the manufacturer of the imaging plate 10, for example, the initial letters of the name of the manufacturer of the imaging plate 10. The front surface unique information 1000 may be the minimum information required to identify the front surface 10x of the imaging plate 10.

[0267] On the front surface 10x of the imaging plate 10, the radiation image forming layer 11 is provided so as to avoid the front surface unique information 1000. In this example, the overall image at the time of emission based on detection of the emitted light L2 and reflected light from the imaging plate 10 includes a reflected light image of the front surface unique information 1000. For example, by confirming that the acquired overall image or the cut-out image displayed on the display unit 3 does not include a reflected light image of the front surface unique information 1000, the user can determine that the imaging plate 10 has been mistakenly inserted face down into the reading device 1, that is, that the imaging plate 10 has been set upside down. Also, by confirming that the acquired overall image or the cut-out image displayed on the display unit 3 includes a reflected light image of the front surface unique information 1000, the user can determine that the imaging plate 10 has been correctly inserted face up into the reading device 1, that is, that the imaging plate 10 has been correctly set.

[0268] It should be noted that the front surface unique information 1000 is not limited to the example in Fig. 61. Furthermore, the front surface unique information 1000 may be displayed on the front surface of the imaging plate 10, and the back surface unique information may be displayed on the back surface of the imaging plate 10.

[0269] Also, the imaging plate 10 may be provided with a convex portion 12 for allowing the user to identify that the imaging plate 10 has been placed face down in the reading device 1, i.e., that the imaging plate 10 has been set upside down. FIG. 62 is a diagram showing an example of a state in which the imaging plate 10 has a convex portion 12. FIG. 62 shows the front surface 10x side of the imaging plate 10. In the example of FIG. 62, the convex portion 12 is provided on the periphery of the imaging plate 10. The convex portion 12 is provided on one of the four sides constituting the periphery of the imaging plate 10, avoiding the central portion. In the example of FIG. 62, the convex portion 12 is provided on a short side of the imaging plate 10, avoiding the central portion. The radiation image forming layer 11 is not formed on the surface of the convex portion 12, and the black anodizing is not performed. The excitation light L10 is reflected on the surface of the convex portion 12 to the same extent as on the surface of the imaging plate 10, for example. Regardless of whether the imaging plate 10 is set upside down or not, the captured overall image based on the image signal output from the detector 40 includes a reflected light image of the convex portion 12. Note that the convex portion 12 may be provided on the long side of the imaging plate 10.

[0270] In this way, since the convex portion 12 is provided on one side of the imaging plate 10 avoiding the center, the position of the convex portion 12 when the imaging plate 10 is viewed from the light source 30 side is always different depending on whether the imaging plate 10 is supported on the back side or the front side.

[0271] Fig. 63 is a schematic diagram showing an example of the imaging plate 10 viewed from the front surface 10x side, similar to Fig. 62. Fig. 63 shows the imaging plate 10 shown in Fig. 62 rotated 180 degrees parallel to its main surface. Figs. 64 and 65 are schematic diagrams showing an example of the imaging plate 10 viewed from its back surface 10y side. Fig. 65 shows the imaging plate 10 shown in Fig. 64 rotated 180 degrees parallel to its main surface.

[0272] As shown in Figures 62 to 65, the position of the protrusion 12 when the imaging plate 10 is viewed from the front surface 10x side is always different from the position of the protrusion 12 when the imaging plate 10 is viewed from the back surface 10y side. As shown in Figures 62 and 63, when the imaging plate 10 is viewed from the front surface 10x side, the protrusion 12 is located closer to the adjacent side in the clockwise direction (the upper side in Figure 62) than the adjacent side in the counterclockwise direction (the lower side in Figure 62) of the side on which the protrusion 12 is provided. In contrast, as shown in Figures 64 and 65, when the imaging plate 10 is viewed from the back surface 10y side, the protrusion 12 is located closer to the adjacent side in the counterclockwise direction (the lower side in Figure 64) than the adjacent side in the clockwise direction (the upper side in Figure 64) of the side on which the protrusion 12 is provided.

[0273] In this way, when the convex portion 12 is provided on one side of the imaging plate 10 while avoiding the center portion, the position of the convex portion 12 is always different when the imaging plate 10 is viewed from the front surface 10x side and when the imaging plate 10 is viewed from the back surface 10y side. Therefore, the position of the convex portion 12 when the imaging plate 10 is viewed from the light source 30 side is always different when the imaging plate 10 is supported from the back surface and when the imaging plate 10 is supported from the front surface. In other words, the position of the convex portion 12 when the imaging plate 10 is viewed from the light source 30 side is always different when the imaging plate 10 is set upside down and when the imaging plate 10 is set correctly. Therefore, the position of the image of the convex portion 12 (i.e., the reflected light image) in the overall image during light emission or the overall image during erasure obtained when the imaging plate 10 is supported from the back surface is always different from the position of the image of the convex portion 12 in the overall image during back insertion obtained when the imaging plate 10 is supported from the front surface. This allows the user to easily determine that the imaging plate 10 is supported with its front side facing up, that is, that the imaging plate 10 has been placed face down in the reading device 1, by checking the position of the image of the convex portion 12 in the acquired overall image displayed on the display unit 3. In other words, the user can easily determine that the imaging plate 10 has been set upside down, by checking the position of the convex portion 12 in the acquired overall image displayed on the display unit 3. From another perspective, it can also be said that the user can easily determine that the imaging plate 10 has been set correctly, by checking the position of the convex portion 12 in the acquired overall image displayed on the display unit 3.

[0274] As shown in FIG. 66, the protrusion 12 may be detachable from the imaging plate 10.

[0275] Furthermore, a plurality of protrusions 12 may be provided on the periphery of the imaging plate 10. Figs. 67 and 68 are schematic diagrams showing an example of a state in which two protrusions 12 are provided on the periphery of the imaging plate 10. Fig. 67 shows the imaging plate 10 viewed from the front surface 10x side, and Fig. 68 shows the imaging plate 10 viewed from the back surface 10y side. In the examples of Figs. 67 and 68, the two protrusions 12 are provided on two opposing sides of the imaging plate 10. Furthermore, when the imaging plate 10 is viewed from the front surface 10x side (or the back surface 10y side), the two protrusions 12 are present at positions that are point-symmetric with respect to the center of the front surface 10x (or the back surface 10y). Even if the two convex parts 12 are provided on the periphery of the imaging plate 10 as shown in Figs. 67 and 68, the position of the image of the convex part 12 in the light emitting overall image or the erased overall image obtained when the imaging plate 10 is supported on the back side is always different from the position of the image of the convex part 12 in the back-inserted overall image obtained when the imaging plate 10 is supported on the front side. Therefore, by checking the position of the image of the convex part 12 in the acquired overall image displayed on the display unit 3, the user can easily specify that the imaging plate 10 has been inserted in the reading device 1 face down, that is, that the imaging plate 10 has been set upside down. Also, by checking the position of the image of the convex part 12 in the acquired overall image displayed on the display unit 3, the user can easily specify that the imaging plate 10 has been inserted in the reading device 1 face up, that is, that the imaging plate 10 has been set correctly.

[0276] Each of the two protrusions 12 may be detachable from the imaging plate 10 as shown in Fig. 69. Also, only one of the two protrusions 12 may be detachable from the imaging plate 10. Also, when at least one protrusion 12 is provided on the imaging plate 10, front surface unique information may be indicated on the front surface 10x of the imaging plate 10, and back surface unique information may be indicated on the back surface 10y of the imaging plate 10.

[0277] As described above, the reader 1 can obtain a radiation image based on the detection of the emitted light L2 and a reflected light image based on the detection of the reflected light, thereby improving the convenience of the reader 1.

[0278] In the above example, the object irradiated with the excitation light L10 is the imaging plate 10, but it may be something other than the imaging plate 10. The object irradiated with the excitation light L10 may be, for example, an evaluation member having an evaluation pattern on its surface for evaluating the image quality of the radiation image read by the reader 1 from the imaging plate 10.

[0279] The evaluation member has, for example, the same size and shape as the imaging plate 10, and is inserted into the reading device 1 through the insertion port 2a of the reading device 1. The evaluation member inserted into the reading device 1 is held by the holder 20 in the same manner as the imaging plate 10. A radiation image forming layer 11 may or may not be formed on the evaluation member. When a radiation image forming layer 11 is formed on the evaluation member, radiation energy is not accumulated in the radiation image forming layer 11.

[0280] When the holding unit 20 holds the evaluation member, the above-mentioned irradiation object 1200 is composed of the holding unit 20 and the evaluation member held by the holding unit 20. Hereinafter, the region on the support side main surface 1200a of the irradiation object 1200 where the image formed by the acted light L2 therefrom is the image of the evaluation member is called the evaluation member image region or simply the member image region. The evaluation member image region can also be said to be the evaluation member existence region on the support side main surface 1200a where the evaluation member exists. In addition, the region excluding the member image region in the detection range R110 is called the evaluation member image outside region or simply the member image outside region. The evaluation member image region corresponds to the IP image region R100, and the evaluation member image outside region (in other words, the member image outside region) corresponds to the IP image outside region R130.

[0281] 70 to 73 are schematic diagrams showing examples of an evaluation member 900. FIG. 70 shows an evaluation member 900 (also referred to as a resolution evaluation member 900A) for evaluating the resolution of a detected radiation image. FIG. 71 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. 72 shows an evaluation member 900 (also referred to as a contrast evaluation member 900C) for evaluating the contrast of a detected radiation image. FIG. 73 shows an evaluation member 900 (also referred to as an artifact evaluation member 900D) for evaluating artifacts in a detected radiation image.

[0282] 70, a resolution evaluation pattern 902a for evaluating the resolution of a detected radiation image is provided on a front surface 901a of a resolution evaluation member 900A. As the resolution evaluation pattern 902a, for example, a line pair chart is used.

[0283] 71, a geometric accuracy evaluation pattern 902b for evaluating the geometric accuracy of a detected radiation image is provided on a 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 grid pattern is used.

[0284] 72, a contrast evaluation pattern 902c for evaluating the contrast of a detected radiation image is provided on a 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 of different brightness (in other words, shading) expressed in grayscale is arranged is used.

[0285] 73, an artifact evaluation pattern 902d for evaluating artifacts in a detected radiation image is shown on a front surface 901d of the artifact evaluation member 900D. For example, a uniform monochromatic pattern is used as the artifact evaluation pattern 902d. For example, a pure white pattern may be used as the artifact evaluation pattern 902d.

[0286] In the reading device 1, the evaluation member 900 is held by the holding unit 20 so that the evaluation pattern faces the light source 30. In other words, the evaluation member 900 is held by the holding unit 20 so that its front surface faces the light source 30. This causes the evaluation pattern of the evaluation member 900 to be irradiated with excitation light L10. Then, the detector 40 detects the reflected light of the excitation light L10 from the front surface of the evaluation member 900 (in other words, the member image area) and the area outside the member image area, and outputs an image signal as the detection result.

[0287] Hereinafter, the image signal obtained as a result of detection of reflected light when the evaluation member 900 is held by the holding portion 20 will be referred to as the evaluation image signal. Also, the overall image based on the evaluation image signal will be referred to as the evaluation overall image. The evaluation overall image contains the evaluation pattern and includes a reflected light image of the evaluation pattern (hereinafter also referred to as the evaluation pattern image). The evaluation overall image does not include a radiation image. The evaluation overall image is composed of only a reflected light image.

[0288] Fig. 74 is a flowchart showing an example of the operation of the reading device 1 when the reading device 1 acquires an evaluation overall image in which an evaluation pattern is captured. When the evaluation member 900 inserted from the insertion slot 2a of the housing 2 is held by the holding unit 20 and the operation unit 4 accepts a predetermined operation from the user, step s51 is executed as shown in Fig. 74. In step s51, the driving unit 50 moves the holding unit 20 to a reading start position under the control of the driving control unit 83. After step s51, step s52 is executed.

[0289] In step s52, the light source 30 irradiates the excitation light L10 onto the front surface and outer region of the evaluation member 900. Then, the detector 40 detects the reflected light of the excitation light L10 on 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.

[0290] After step s52, in step s53, the drive unit 50 moves the holder 20 to the ejection position under the control of the drive control unit 83. Next, in step s54, the evaluation member 900 is ejected to the outlet 2b of the housing 2. Then, in step s55, the display control unit 82 displays the evaluation overall image, for example in grayscale, on the display unit 3 based on the evaluation image signal. When the resolution evaluation member 900A is inserted into the reading device 1, in step s55, the evaluation overall image including the image of the resolution evaluation pattern 902a is displayed. When the geometric accuracy evaluation member 900B is inserted into the reading device 1, in step s55, the evaluation overall image including the image of the geometric accuracy evaluation pattern 902b is displayed. When the contrast evaluation member 903C is inserted into the reading device 1, in step s55, the evaluation overall image including the image of the contrast evaluation pattern 902c is displayed. When the artifact evaluation member 900D is inserted into the reading device 1, in step s55, an evaluation overall image including an image of the artifact evaluation pattern 902d is displayed. Note that step s55 may be executed at any time after step s52.

[0291] The user can evaluate the image quality of the detected radiation image based on the evaluation pattern image included in the evaluation overall image displayed on the display unit 3. In other words, 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. The user also 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. The user also evaluates the contrast of the detected radiation image based on the image of the contrast evaluation pattern 902c displayed on the display unit 3. The user also evaluates the artifacts of the detected radiation image based on the image of the artifact evaluation pattern 902d displayed on the display unit 3.

[0292] In this manner, in this example, the light source 30 and detector 40 are used to obtain a detected radiation image, and an evaluation image signal is obtained as a result of detection of the excitation light L10 reflected from the front surface of the evaluation member 900. For this reason, the image quality of the detected radiation image can be appropriately evaluated on the basis of the evaluation pattern image included in the reflected light image which is based on the evaluation image signal.

[0293] The evaluation member 900 may be made of, for example, paper, resin, or metal. The evaluation pattern may be printed on the front surface of the evaluation member 900. At least one of the resolution evaluation pattern 902a and the geometric accuracy evaluation pattern 902b may be made of 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 a printing technique. This makes it possible to more appropriately evaluate the image quality of the detected radiation image. The evaluation member 900 may be made of printed paper on which the evaluation pattern is printed. In this case, the image quality of the detected radiation image can be evaluated using an inexpensive evaluation member 900. The evaluation member 900 may be made of cardboard.

[0294] <Other configuration examples of the reading device> In the above example, the holding unit 20 moves, but the holding unit 20 does not have to move. In this case, the light source 30, the detector 40, and the erasing light source 70 move while the holding unit 20 is stopped, thereby realizing the same processing as described above in the reading device 1. Also, the light source 30, the detector 40, the erasing light source 70, and the holding unit 20 may move.

[0295] Furthermore, the reader 1 may include a plurality of light sources. Fig. 73 is a schematic diagram showing a configuration example of a reader 1 (also called a reader 1A) that includes two light sources.

[0296] As shown in FIG. 75, the reading device 1A includes the above-mentioned light source 30 and another light source 130. The light source 130 can irradiate the imaging plate 10 or the evaluation member 900 held in the holding unit 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, a visible laser light. The wavelength of the irradiation light L11 may be the same as or different from the wavelength of the excitation light L10. The light source 130 is controlled by the light emission control unit 86, similar to the light source 30. The irradiation light L11 can also be said to be the action light L1.

[0297] The light source 130 may be used, for example, in step s22 in FIG. 27 described above. In this case, in step s22, the light source 130, not the light source 30, irradiates the front surface (in other words, the IP image area) and the area outside the IP image area of ​​the erased imaging plate 10 with the irradiation light L11. In step s22, the light source 130, like the light source 30, repeatedly executes a process of scanning the irradiation light L11 on the imaging plate 10 and the area outside the IP image area in the main scanning direction DRm under the control of the light emission control unit 86. Meanwhile, in step s22, the drive unit 50 moves the holding unit 20 holding the imaging plate 10 in the sub-scanning direction DRs, like the above-mentioned reading process. While the holding unit 20 is moving in the sub-scanning direction DRs, a process of scanning the irradiation light L11 in the main scanning direction DRm is repeatedly executed, whereby the irradiation light L11 is raster-scanned on the imaging plate 10 and the area outside the IP image area, like the excitation light L10. In step s22, while the irradiated light L11 is raster-scanned on the imaging plate 10, the detector 40 detects the reflected light of the irradiated light L11 from the imaging plate 10 and outputs an image signal at erasure as the detection result. The overall image at erasure based on this image signal at erasure includes an IP overall reflected light image and an image of a region outside the IP image region, and does not include a radiation image, as with the overall image at erasure based on the detection of the reflected light of the excitation light L10. In step s27 of FIG. 27, the overall image at erasure based on the detection of the reflected light of the irradiated light L11 is displayed. The reading device 1A can use the overall image at erasure based on the detection of the reflected light of the irradiated light L11, as with the overall image at erasure based on the detection of the reflected light of the excitation light L10. For example, the reading device 1A may specify the IP inclination angle or the IP size based on the overall image at erasure based on the detection of the reflected light of the irradiated light L11. The reflected light of the irradiated light L11 is included in the acted light L2.

[0298] 27 is executed by the reading device 1A when the imaging plate 10 is inserted face down into the reading device 1A, an overall image when the imaging plate 10 is inserted face down based on detection of the reflected light of the irradiation light L11 is obtained in step s22, similar to the overall image when the imaging plate 10 is inserted face down based on detection of the reflected light of the excitation light L10. The user can specify that the imaging plate 10 is inserted face down into the reading device 1A based on the overall image when the imaging plate 10 is inserted face down displayed on the display unit 3 of the reading device 1A.

[0299] The light source 130 may also be used in step s52 in FIG. 74 described above. In this case, in step s52 in the reading device 1A, the light source 130, not the light source 30, irradiates the front surface of the evaluation member 900 and the region outside the member image region with the irradiation light L11. 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 irradiation light L11 is raster-scanned on the evaluation member 900 and the region outside the member image region, the detector 40 detects the reflected light of the irradiation light L11 from the evaluation member 900 and the outer region, and outputs an evaluation image signal as the detection result. The evaluation overall image based on this evaluation image signal includes an evaluation pattern image and does not include a radiation image, like the above-mentioned evaluation overall image based on the detection of the reflected light of the excitation light L10. 74, in step s55, an evaluation overall image based on the detection of reflected light of the irradiated light L11 is displayed on the display unit 3, based on the evaluation image signal obtained in step s52. The user can evaluate the image quality of the detected radiation image based on the evaluation pattern image included in the evaluation overall image displayed on the display unit 3 of the reading device 1A.

[0300] The reader 1 may include a plurality of detectors. Fig. 76 is a schematic diagram showing a configuration example of a reader 1 (also called a reader 1B) including two detectors and one light source.

[0301] As shown in FIG. 76, the reading device 1B includes the above-mentioned detector 40 and a detector 140 that is different from the detector 40. The reading device 1B also includes a light source 30, but does not include a light source 130. The detector 140 has, for example, a similar configuration to the detector 40. The detector 140 can detect the emitted light L2 from the imaging plate 10, similar to the detector 40. The detector 140 can detect the reflected light of the excitation light L10 from the imaging plate 10 or the evaluation member 900, and the reflected light of the excitation light L10 from the region outside the IP image region or the region outside the member image region, similar to the detector 40.

[0302] The detector 140 may be used, for example, in step s22 in FIG. 27 described above. In this case, in the reading device 1B, while the light source 30 raster scans the front surface of the erased imaging plate 10 and the area outside the IP image area in step s22, the detector 140 detects the reflected light of the excitation light L10 from the imaging plate 10 and the area outside the IP image area, and outputs an image signal at the time of erasure as the detection result. The overall image at the time of erasure based on this image signal at the time of erasure includes an IP overall reflected light image and an image of the area outside the IP image area, but does not include a radiation image, like the overall image at the time of erasure described up to now. The reading device 1B can perform various processes, such as identifying the IP tilt angle, based on the overall image at the time of erasure acquired in step s22.

[0303] In addition, when the imaging plate 10 is inserted into the reading device 1B face down and the processing of Figure 27 is executed by the reading device 1B, in step s22, an overall image when the imaging plate 10 is inserted face down, which shows the back side of the imaging plate 10, is obtained, similar to the overall image when the imaging plate 10 is inserted face down as described above.

[0304] The detector 140 may also be used, for example, in step s52 in Fig. 74 described above. In this case, in the reading device 1B, while the light source 30 is raster scanning the front surface of the evaluation member 900 and the area outside the member image area in step s52, the detector 140 detects the reflected light of the excitation light L10 from the evaluation member 900 and the area outside the member image area, and outputs an evaluation image signal as the detection result. The evaluation overall image based on this evaluation image signal includes an evaluation pattern image and does not include a radiation image, like the evaluation overall images described so far.

[0305] The reader 1 may include a plurality of detectors and a plurality of light sources. Fig. 77 is a schematic diagram showing a configuration example of a reader 1 (also called a reader 1C) including detectors 40 and 140 and light sources 30 and 130.

[0306] The reading device 1C may use the detector 140 and the light source 130, for example, in step s22 of FIG. 27 described above. In this case, in the reading device 1C, while the light source 130 raster scans the front surface and the IP image area outside area of ​​the erased imaging plate 10 in step s22, the detector 140 detects the reflected light of the excitation light L10 from the imaging plate 10 and the IP image area outside area, and outputs an image signal at the time of erasure as the detection result. The entire image at the time of erasure based on this image signal at the time of erasure includes an IP entire reflected light image and an IP image area outside area image, and does not include a radiation image, like the entire image at the time of erasure described so far. Note that when the processing of FIG. 24 is performed in the reading device 1C when the imaging plate 10 is inserted in the reading device 1C facing down, an acquired entire image showing the back surface of the imaging plate 10 is obtained in step s22.

[0307] The reading device 1C may also use the detector 140 and the light source 130, for example, in step s52 in Fig. 74 described above. In this case, in the reading device 1C, while the light source 130 is raster scanning the front surface of the evaluation member 900 and the area outside the member image area in step s52, the detector 140 detects the reflected light of the excitation light L10 from the evaluation member 900 and the area outside the member image area, and outputs an evaluation image signal as the detection result. The evaluation overall image based on this evaluation image signal includes an evaluation pattern image and does not include a radiation image, like the evaluation overall images described so far.

[0308] In the reading devices 1A and 1C, the light source 130 may output light other than visible light as the irradiated light L11. For example, the irradiated light L11 may be infrared light or ultraviolet light. In this case, detectors capable of detecting infrared light or ultraviolet light are used as the detectors 40 and 140.

[0309] In the readers 1B and 1C, the detector 140 that detects the reflected light of the irradiated light L11 may include, for example, a CCD sensor or a CMOS sensor used in a camera. CCD is an abbreviation for Charge Coupled Device, and CMOS is an abbreviation for Complementary Metal Oxide Semiconductor.

[0310] Furthermore, in the reading device 1C, the light source 130 may not scan the irradiation light L11, but may irradiate the entire range of the imaging plate 10 or the evaluation member 900 with the irradiation light L11 in one irradiation like the erasing light source 70. In this case, the detector 140 may include, for example, a CCD sensor or a CMOS sensor used in a camera.

[0311] In addition, in the reading devices 1B and 1C, the detector 40 does not have to be able to detect the reflected light of the excitation light L10. In this case, the optical filter 42 of the detector 40 does not have to transmit the excitation light L10. In addition, in the reading device 1C, the detector 40 does not have to 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.

[0312] In the overall image at the time of emission acquired when the detector 40 does not detect the reflected light of the excitation light L10, when the imaging plate 10 includes an unexposed portion, the brightness value of the unexposed region image and the brightness value of the region image outside the IP image region are similar values. Therefore, when the imaging plate 10 includes an unexposed portion, it is difficult for the image processing unit 81 to specify the IP tilt angle and IP size based on the overall image at the time of emission in the above-mentioned method using a binary image. However, even when the imaging plate 10 includes an unexposed portion, the image processing unit 81 can appropriately specify the IP tilt angle and IP size as described above based on the overall image at the time of erasure based on the image signal at the time of erasure output by the detector 140.

[0313] In the reading devices 1B and 1C, the detector 140 may not detect the stimulated emission L5. In this case, the reading devices 1B and 1C can obtain an IP total reflection light image without erasing the radiation image from the imaging plate 10. For example, the reading device 1B may operate the detectors 40 and 140 simultaneously in the reading process of the above-mentioned step s2. In this case, the detection of the excited region light L20 by the detector 40 and the detection of the reflected light of the excitation light L10 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 as the overall image when erased, and includes the IP total reflection light image and the IP image region outside image, but does not include the radiation image. In the reading device 1C, the light sources 30 and 130 may be operated simultaneously, and the detectors 40 and 140 may be operated simultaneously in the reading process of the above-mentioned step s2. In this case, the detector 40 detects the excited region light L20 and the detector 140 detects the reflected light of the irradiation light L11 from the imaging plate 10 in parallel. In this case, too, the overall image based on the image signal output by the detector 140 is the same as the overall image at the time of erasure, and includes the IP overall reflected light image and the IP image region outside image, but does not include a radiation image. In this way, in the reading process, not only a radiation image based on the detection of the excited region light L20 but also a reflected light image based on the detection of the reflected light of the excitation light L10 or the irradiation light L11 is obtained, thereby making it unnecessary to perform the processes of steps s21 and s22 in FIG. 27. In other words, in the series of processes in FIG. 18 described above, a radiation image based on the detection of the excited region light L20 and a reflected light image based on the detection of the reflected light of the excitation light L10 or the irradiation light L11 can be obtained. This makes it possible to simplify the operation of the reading device 1.

[0314] 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 unit 13 located outside the housing 2, in addition to or instead of the display unit 3 provided in the housing 2. FIG. 78 is a schematic diagram showing an example of the configuration of a reading device 1 (also called a reading device 1D) that includes a display unit 13 on the outside of the display surface of the housing 2. The display unit 13 can also be called a display device 13.

[0315] The display unit 13 is, for example, a liquid crystal display device or an organic EL display device, and can display various information such as characters, symbols, figures, and images. The display unit 13 is controlled by a display control unit 82 of the control unit 80 in the housing 2. The display control unit 82 can control the display unit 13 through, for example, an interface unit 95 in the housing 2. The communication between the interface unit 95 and the display unit 13 may be compliant with USB, DisplayPort, or HDMI (High-Definition Multimedia Interface) (registered trademark). The interface unit 95 may be connected to the display unit 13 by wire or wirelessly. The display unit 13 may display the entire acquired image or a cut-out image. In the example of FIG. 78, the display unit 3 is provided in the housing 2 of the reading device 1D, but the display unit 3 may not be provided. In addition, the reading device 1D may be provided with a plurality of light sources or a plurality of detectors as shown in FIGS. 75 to 77.

[0316] 79 and 80 are schematic diagrams showing another example of the configuration of the reading device 1. In the reading device 1 (also called the reading device 1E) shown in FIGS. 79 and 80, a computer device 950 having a part of the functions of the reading device 1E is provided outside the housing 2. As shown in FIG. 80, the computer device 950 includes, for example, the above-mentioned display unit 3, image processing unit 81, and display control unit 82. The computer device 950 may be, for example, a personal computer (also called a general-purpose computer). In this case, the computer device 950 may be a notebook type or a desktop type. Hereinafter, in the reading device 1E, the housing 2, the multiple components integrated by the housing 2, and the AC adapter 5 may be collectively referred to as the reading device main body 9.

[0317] The computer device 950 is capable of communicating with the reading device main body 9. The computer device 950 includes, for example, a control unit 951 having an image processing unit 81 and a display control unit 82, and an interface unit 952 that communicates with the reading device main body 9. The computer device 950 also includes an operation unit 953 that accepts operations from a user.

[0318] The control unit 951 can comprehensively manage the operation of the computer device 950 and can also be called a control circuit. The control unit 951 can control, for example, the display unit 3 and the interface unit 952. In addition, the control unit 951 can perform processing according to a user operation received by an operation unit 953.

[0319] The control unit 951 includes, for example, at least one processor and a storage unit, and can be said to be a type of computer device. The at least one processor included in the control unit 951 may include a CPU or a processor other than the CPU. In the control unit 951, various functions are realized by the at least one processor executing a program in a storage unit (also called a storage circuit). In the control unit 951, the above-mentioned image processing unit 81 and display control unit 82 are formed as functional blocks by the at least one processor executing a program in the storage unit.

[0320] The operation unit 953 includes, for example, a keyboard and a mouse. The operation unit 953 may include a touch sensor that detects a touch operation by a user. When the operation unit 953 includes a touch sensor, the touch sensor and the display unit 3 may form a touch panel display having a display function and a touch detection function.

[0321] The interface unit 952 can communicate with the interface unit 95 of the reading device main body 9. The communication between the interface unit 952 and the interface unit 95 of the reading device main body 9 may be compliant with Ethernet, USB, WiFi, or other standards. The interface unit 952 may perform wired communication with the interface unit 95, or may perform wireless communication. The interface unit 952 may be an interface circuit, a communication unit, or a communication circuit. The control unit 951 of the computer device 950 and the control unit 80 of the reading device main body 9 can exchange information with each other through the interface unit 952 and the interface unit 95.

[0322] In the reading device 1E, the control unit 951 of the computer device 950 and the control unit 80 of the reading device main body 9 cooperate with each other to execute the above-mentioned various processes performed by the control unit 80. In the reading device 1E, the detection control unit 85 outputs the image signal output by the detector 40 to the interface unit 95. The interface unit 95 outputs the input image signal to the interface unit 952. The interface unit 952 inputs the input image signal to the control unit 951. The image processing unit 81 performs the above-mentioned image processing on the image signal input to the control unit 951. Then, the image processing unit 81 performs the above-mentioned inclination angle specification processing, size specification processing, and cut-out processing based on the image signal after the image processing. Also, the display control unit 82 causes the display unit 3 to display, for example, the acquired overall image based on the image signal after the image processing.

[0323] The operation unit 953 of the computer device 950 may receive at least a part of the multiple user operations received by the operation unit 4 of the reading device main body 9. For example, the operation unit 953 may receive a user operation instructing the start of the series of processes in FIG. 18, may receive a user operation instructing the start of the series of processes in FIG. 26, may receive a user operation instructing the start of the series of processes in FIG. 27, or may receive a user operation instructing the start of the series of processes in FIG. 74. In this case, the control unit 951 notifies the reading device 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 operation received by the operation unit 953.

[0324] Furthermore, the operation unit 953 may accept a user operation that is not accepted by the operation unit 4, and the operation unit 4 may accept a user operation that is not accepted by the operation unit 953. Furthermore, when a user operation accepted by the operation unit 953 conflicts with a user operation accepted by the operation unit 4, the reading device 1E may, for example, preferentially execute a process according to the user operation accepted by the reading device main body 9.

[0325] The reading device 1E may include a display unit provided on the housing 2 as shown in FIG. 1 and the like. The reading device 1E may include a plurality of light sources or a plurality of detectors as shown in FIGS. 75 to 77. The reading device 1E may not include either one of the operation units 4 and 953. In the reading device 1E, the control unit 80 of the reading device main body 9 may execute some of the processes executed by the image processing unit 81 of the computer device 950 instead. For example, the control unit 80 may execute image processing on the image signal from the detector 40, and the image signal after the image processing may be input to the image processing unit 81.

[0326] As described above, the reading device 1 has been described in detail, but the above description is merely an example in all respects, and this disclosure is not limited thereto. In addition, the above-mentioned various modified examples can be combined and applied as long as they are not mutually inconsistent. It is understood that countless modified examples not exemplified can be envisioned without departing from the scope of this disclosure. [Explanation of symbols]

[0327] 1,1A,1B,1C,1D,1E Reading device 10 Imaging Plate 30,130 light sources 40,140 detectors 81 Image processing section 100a, 100b, 200 Overall view 101a,101b,151a Radiographic image 103a, 103b, 151b Unexposed area images 151 Cut out image L1 excitation light L4,L40 Reflected light L5 Radiant Light

Claims

1. A reading device for reading a radiation image from an imaging plate, comprising: a support surface for supporting the imaging plate; a light source that irradiates excitation light onto the imaging plate supported by the support surface and onto a peripheral region of the support surface that supports the imaging plate and is located around the imaging plate; a detector for detecting photostimulated luminescence from the imaging plate due to the excitation light and reflected light of the excitation light from the imaging plate and the peripheral area; Equipped with A reading device, wherein the peripheral area is treated so that the excitation light is less likely to be reflected by the imaging plate.

2. 2. The reading device according to claim 1, The imaging plate is an excited region that is irradiated with radiation and excited by the excitation light; The unexposed part of the radiation and Including, The detector detects the stimulated luminescence from the excited region and the reflected light from the excited region, the unexposed portion and the peripheral region.

3. 3. The reading device according to claim 1 or 2, When the stimulated emission from the imaging plate and the reflected light from the imaging plate and the peripheral area are treated as acted upon light, A reading device comprising a display unit for displaying an overall image based on the detection of the acted light by the detector.

4. 3. The reading device according to claim 1 or 2, The stimulated light from the imaging plate and the reflected light from the imaging plate and the peripheral area are treated as acted lights, and the stimulated light and the reflected light from the imaging plate are treated as IP acted lights. A reading device comprising: a setting unit that sets an extraction range for extracting an IP image based on the detection of the IP acted light by the detector from an entire image based on the detection of the acted light by the detector.

5. 5. The reading device according to claim 4, A reading device comprising a display unit that displays the IP image cut out from the entire image.

6. 3. The reading device according to claim 1 or 2, When the light emitted by the imaging plate in response to the action of the excitation light is defined as IP acted light, the detector outputs an IP acted light image signal which is an image signal resulting from the detection of the IP acted light; a reading device comprising a size determination unit for determining a size of the imaging plate based on the IP acted-on light image signal.

7. 3. The reading device according to claim 1 or 2, When the light emitted by the imaging plate in response to the action of the excitation light is defined as IP acted light, the detector outputs an IP acted light image signal which is an image signal resulting from the detection of the IP acted light; a tilt angle specifying unit that specifies a tilt angle of the imaging plate from a reference position based on the IP acted-on light image signal;

8. 3. The reading device according to claim 1 or 2, When the light emitted by the imaging plate in response to the action of the excitation light is defined as IP acted light, the detector outputs an IP acted light image signal which is an image signal resulting from the detection of the IP acted light; an image processing unit that processes a detected image signal from the detector, the image processing unit sets a cutout range for cutting out an IP living body radiography image, which is an image based on the detection of the IP acted light, from a living body radiography image, which is an image obtained by scanning the imaging plate, which serves as a light receiver for radiography of a living body, with the excitation light; Reading device.

9. 3. The reading device according to claim 1 or 2, When the light emitted by the imaging plate in response to the action of the excitation light is defined as IP acted light, the detector outputs an IP acted light image signal which is an image signal resulting from the detection of the IP acted light; A display unit; A display control unit that controls the display unit; Equipped with The display control unit is a reading device that simultaneously and separately displays an acquired image obtained from radiation photography of a living body and an imaging plate shape extraction image representing the shape of the imaging plate extracted by processing the IP acted light image signal.

10. 3. The reading device according to claim 2, an image processing unit that processes a detected image signal from the detector, The image processing section is a reading device which generates an IP image consisting of a radiation image obtained by the detector detecting the stimulated emission and an unexposed area image obtained by detecting the reflected light from the unexposed area.

11. 11. The reading device according to claim 10, A reading device in which, when the detector detects the reflected light from the peripheral area and defines the reflected light image as an IP outer area image, the image processing unit generates an acquired overall image consisting of the IP image and the IP outer area image.

Images