JP2013005905A - Radiographic imaging system and operating method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce difference in image quality between two radiation images which are acquired by stereo imaging.SOLUTION: In the radiographic imaging system 100 in which a radiation source 17 emits radiation from two imaging directions different from each other and a radiation detector 15 detects part of the emitted radiation via a grid 50, a transmittance storage unit stores in advance a transmittance of radiation transmitting through the grid 50 in association with an imaging direction, a command receiving unit 3 receives user commands related to the two imaging directions, and an angle setting unit sets the angle of convergence on the basis of the stored transmittance and the user command so that the rate of the transmittance of one imaging direction with respect to the transmittance of the other imaging direction becomes greater than or equal to 50%.

Description

  The present invention relates to a radiation imaging apparatus that irradiates radiation from two different imaging directions and detects the radiation through a grid that absorbs part of the irradiated radiation, and an operation method thereof.

  In a radiation imaging apparatus, by disposing a grid between a subject and a radiation detector, radiation scattered toward the subject is absorbed and radiation having a high S / N is absorbed by the subject. It is known to detect. In general, this grid is configured at a predetermined interval so that a large number of radiation absorbing members converge toward a radiation source at the reference position with a predetermined position with respect to the radiation detector as a reference position. is there. As a result, a direct line that is linearly incident on the radiation detector from the radiation source can be transmitted, and a scattered line that is scattered by the subject and incident obliquely can be absorbed by the radiation absorbing member.

  By the way, in recent years, in order to make diagnosis easier, stereoscopic viewing is possible by irradiating the subject from two or more different directions and detecting the radiation that has passed through the subject and acquiring the radiation images having parallax with each other. Taking a radiological image (hereinafter referred to as stereo imaging) has been performed. The grid can also be applied to a radiation imaging apparatus capable of performing this stereo imaging. Patent Document 1 includes a plurality of X-ray sources, and a predetermined interval is provided in a direction orthogonal to the arrangement direction of these X-ray sources. There has been proposed a radiation imaging apparatus including a grid made of shielding members arranged in an open manner.

JP 2010-233962 A

  However, in a radiation apparatus capable of performing stereo imaging, the radiation source in at least one imaging direction irradiates the radiation with a deviation from the reference position. Therefore, a part of the direct line irradiated with the deviation from the reference position is partly. It will be scraped by the radiation absorbing member of the grid. Thus, the ratio of the radiation which permeate | transmits a grid among the radiation irradiated toward the grid changes according to an imaging | photography direction.

The reference position varies depending on the grid configuration, and the combination of two shooting directions when performing stereo shooting can be freely set by the user. Therefore, if the user sets a combination of two shooting directions without considering the transmittance in the shooting direction, the transmittance in one shooting direction may be significantly larger than the transmittance in the other shooting direction. possible. In such a case, the image quality of the other radiographic image is significantly deteriorated compared to the image quality of the one radiographic image, for example, sharpness is significantly lower,
There is a possibility that it is difficult for the user to perform stereoscopic viewing.

  In view of the above circumstances, an object of the present invention is to reduce a difference in image quality between radiographic images obtained by stereo imaging in a radiographic apparatus capable of performing stereo imaging and an operation method thereof.

  In order to solve the above problems, a radiation imaging apparatus of the present invention includes a radiation source that irradiates radiation from two different imaging directions, a grid that absorbs part of the radiation emitted from the radiation source, and a grid. A radiation detector that detects radiation emitted through the grid, a transmittance storage unit that stores in advance the transmittance, which is the ratio of the radiation that passes through the grid, in association with the imaging direction, and receives user instructions regarding the two imaging directions Based on the stored transmittance and the received user instruction so that the ratio of the transmittance in the other shooting direction to the transmittance in the one shooting direction of the two shooting directions is 50% or more. And an angle setting unit for setting an angle formed by two shooting directions.

  The operation method of the radiation imaging apparatus of the present invention includes a radiation source that irradiates radiation from two different imaging directions, a grid that absorbs part of the radiation emitted from the radiation source, and radiation that is irradiated through the grid. The radiation detector includes a radiation detector that detects a part of the radiation imaging apparatus and an angle setting unit that sets an angle between two imaging directions. The transmittance storage unit is a ratio of radiation that passes through the grid. A certain transmittance is stored in advance in association with the shooting direction, the instruction receiving unit receives a user instruction regarding the two shooting directions, and the angle setting unit has the other of the two shooting directions with respect to the transmittance in one shooting direction. The angle between the two shooting directions is set based on the stored transmittance and the received user instruction so that the ratio of the transmittance in the shooting direction is 50% or more. It is characterized in.

  Here, “absorbing a part of radiation” in the radiation imaging apparatus and operation method of the present invention means absorbing a part of the radiation irradiated toward the grid. Further, the “transmittance” means the proportion of the radiation that passes through the grid out of the radiation irradiated toward the grid without passing through the subject.

  In the radiation imaging apparatus of the present invention, the angle setting unit sets the angle formed by the two imaging directions so that the ratio of the transmittance in the other imaging direction to the transmittance in the one imaging direction is 80% or more. You may do.

  In the radiation imaging apparatus of the present invention, the instruction receiving unit receives an angle instruction from the user regarding the angle formed by the two imaging directions, and the angle setting unit sets the stored transmittance to the indicated angle. Based on this, the angle formed by the two shooting directions may be set so as to be closest to the instructed angle.

  In the radiation imaging apparatus of the present invention, the instruction receiving unit includes an instruction receiving unit that receives an instruction of an imaging direction from the user with respect to one imaging direction, and the angle setting unit is instructed as one of the stored transmittances. An angle formed by the two shooting directions may be set based on the transmittance with respect to the shooting direction.

  In the radiation imaging apparatus of the present invention, the transmittance storage unit may store the imaging direction in advance by associating the imaging direction with an imaging angle that is an angle between the imaging direction and a direction orthogonal to the surface of the grid. The shooting angle may be obtained by dividing a predetermined angle range into predetermined angles.

  In the radiation imaging apparatus of the present invention, the angle setting unit may set an angle formed by the first imaging direction and the second imaging direction in a range of 2 ° to 8 °. In the radiation imaging apparatus of the present invention, one imaging direction may be a direction orthogonal to the surface of the grid. In the radiation imaging apparatus of the present invention, the grid may be integrated with the surface of the radiation detector.

  According to the radiation imaging apparatus and the operation method of the present invention, the transmittance storage unit stores in advance the transmittance, which is the ratio of the radiation that passes through the grid, in association with the imaging direction, and the instruction receiving unit relates to the two imaging directions. A user instruction is accepted, and the angle setting unit accepts the stored transmittance and the ratio so that the ratio of the transmittance in the other photographing direction to the transmittance in one photographing direction of the two photographing directions is 50% or more. Since the angle formed by the two imaging directions is set based on the user instruction, the difference in image quality between the radiographic images obtained by stereo imaging can be reduced.

  Further, according to the radiographic apparatus of the present invention, the angle setting unit forms an angle formed by the two imaging directions so that the ratio of the transmittance in the other imaging direction to the transmittance in the one imaging direction is 80% or more. Therefore, the difference in image quality between radiographic images obtained by stereo imaging can be further reduced.

  According to the radiation imaging apparatus of the present invention, the instruction receiving unit receives an angle instruction from the user regarding the angle formed by the two imaging directions, and the angle setting unit receives the stored transmittance and the indicated angle. Since the angle between the two imaging directions is set so as to be the closest to the instructed angle, the difference in image quality between the radiographic images can be reduced by stereo imaging having a sense of depth desired by the user. .

  Further, according to the radiation imaging apparatus of the present invention, the instruction receiving unit receives an instruction of the imaging direction from the user with respect to one imaging direction, and the angle setting unit receives the one of the imagings instructed with the stored transmittance. Since the angle between the two imaging directions is set based on the transmittance with respect to the direction, the difference in image quality between the radiographic images obtained by stereo imaging including the radiographic images captured from the imaging direction desired by the user is reduced. it can.

  In addition, according to the radiation imaging apparatus of the present invention, the angle setting unit sets the angle formed by the two imaging directions in the range of 2 ° to 8 °, and therefore the radiation obtained by stereo imaging that can be viewed stereoscopically by the user. The difference in image quality between images can be reduced.

  According to the radiation imaging apparatus of the present invention, since one imaging direction is a direction orthogonal to the surface of the grid, a radiographic image captured from one imaging direction can be used as a radiographic image for planar view. The difference in image quality between radiographic images obtained by stereo imaging can be reduced.

  Further, according to the radiation imaging apparatus of the present invention, since the grid is integrated with the detection surface of the radiation detector, the stereo and the radiation detector can be prevented from being misaligned with each other for a long time. The difference in image quality between radiographic images obtained by imaging can be reduced.

Schematic configuration diagram of radiation imaging equipment Partial front view of the radiography system Enlarged view of the main part of the radiography system Block diagram showing the configuration of the computer Diagram showing correspondence between shooting angle and transmittance Flow chart showing a series of processing by the radiation imaging apparatus

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a radiation imaging apparatus according to an embodiment of the present invention, and FIG. 2 is a partial front view of the radiation imaging apparatus main body. As shown in FIG. 1, the radiation imaging apparatus 100 includes an imaging apparatus body 1 that can perform stereo imaging, a monitor 2 that displays a radiographic image captured by the imaging apparatus body 1, an input unit 3 as an instruction receiving unit, and imaging. A computer 4 connected to the apparatus main body 1, a monitor 2 and an input unit 3 is provided.

  First, the photographing apparatus main body 1 will be described with reference to FIGS. 1 and 2. The imaging apparatus main body 1 acquires two image data DL and DR corresponding to the left-eye image GL and the right-eye image DL by taking a stereo image of the subject breast M, as shown in FIG. The base 11 includes a rotary shaft 12 that is movable in the vertical direction (Z direction) with respect to the base 11 and that is rotatable, and an arm portion 13 that is connected to the base 11 by the rotary shaft 12.

  The arm portion 13 has an alphabet C shape, and a radiation table 16 is attached to one end of the arm portion 13 so as to face the imaging table 14 at the other end. The rotation and vertical movement of the arm unit 13 are controlled by an arm controller 31 incorporated in the base 11.

  The imaging table 14 includes a radiation detector 15 such as a flat panel detector, a detector controller 33 that controls reading of image data from the radiation detector 15, and a grid 50. The imaging table 14 includes a charge amplifier that converts the charge signal read from the radiation detector 15 into a voltage signal, a correlated double sampling circuit that samples the voltage signal output from the charge amplifier, a voltage A circuit board provided with an AD conversion unit for converting a signal into a digital signal is also installed. In addition, the photographing table 14 is configured to be rotatable with respect to the arm unit 13, and even when the arm unit 13 rotates with respect to the base 11, the direction of the photographing table 14 is fixed to the base 11. can do.

  The radiation detector 15 detects radiation applied to the detection surface 15a, and may use a so-called direct type radiation detector that directly receives the irradiation of radiation to generate electric charge. A so-called indirect radiation detector that converts visible light and converts the visible light into a charge signal may be used. As a charge signal reading method, image data is read by turning on / off a TFT (thin film transistor) switch, or a so-called TFT reading method, or image data is read by irradiating reading light. It is desirable to use a so-called optical readout system, but the present invention is not limited to this, and other systems may be used.

  The grid 50 absorbs a part of scattered rays scattered by the breast M and direct rays irradiated with deviation from the reference position. Further, the grid 50 is arranged integrally with the radiation detector 15 on the detection surface 15a so that the center position of the back surface of the grid 50 and the center position of the detection surface 15a of the radiation detector 15 coincide. Thereby, the position shift with the radiation detector 15 by use for a long time can be avoided.

  FIG. 3 is an enlarged view of a main part around the grid 50 in the photographing apparatus main body 1. In FIG. 3, only the imaging table 14, the radiation detector 15, the radiation source 17, and the grid 50 are illustrated, and other members are omitted. In FIG. 3, the breast M is not installed on the imaging table 14.

  As shown in FIG. 3, the grid 50 is mainly composed of a plurality of shielding members 51 made of a radiation absorbing material and a filler 52 made of a radiation transmitting material. The shielding member 51 is a plate-like member having a thickness of about 0.1 mm, a height of about 3 to 15 mm, and a width of about 450 mm. The powdery simple substance or powdery lead oxide, bismuth compound, Alternatively, other heavy metal compounds are mixed into a solution to form a solution using an organic polymer as a binder, and this solution is applied onto a flat surface to form a thin plate, such as lead foil, tantalum, and bismuth. It is formed of a single plate material. The filler 52 is made of a foamable resin such as foamed polystyrene, foamed polypropylene, foamed polyurethane, or the like.

  In the grid 50, a plurality of shielding members 51 are arranged with a predetermined interval therebetween. These shielding members 51 are arranged so as to converge at one point on the axis passing through the center position of the back surface of the grid 50. One point on this axis is the reference position P of the radiation source 17. The reference position P varies depending on the grid and is not particularly limited. The reference position P of the grid 50 in this embodiment will be described later.

  As shown in FIG. 3, the shielding members 51 are spaced from each other so as to be in the same direction as the radiation direction of the direct line R that is linearly incident on the radiation detector 15 from the radiation source 17 located at the reference position P. Are arranged. Further, the filler 52 is filled in the gaps between the shielding plate members 51.

  Description will be made with reference to FIGS. 1 and 2 again. A radiation source 17 and a radiation source controller 32 are stored inside the radiation irradiation unit 16. The radiation source controller 32 controls the timing of irradiating radiation from the radiation source 17 and the radiation generation conditions (tube current (mA), irradiation time (ms), tube voltage (kV), etc.) in the radiation source 17. .

  Further, in the central portion of the arm portion 13, a compression plate 18 that is disposed above the imaging table 14 and presses and compresses the breast M, a support portion 20 that supports the compression plate 18, and a support portion 20 that extends in the vertical direction. A moving mechanism 19 for moving in the (Z direction) is provided. The position of the compression plate 18 and the compression pressure are controlled by the compression plate controller 34.

  Next, the monitor 2 will be described. The monitor 2 is configured to display the left-eye image GL and the right-eye image GR using the two image data DL and DR output from the computer 4. As a display method of the monitor 2, for example, the left-eye image GL and the right-eye image GR are displayed using two screens, and the left-eye image GL is displayed by the user by using a half mirror, polarizing glass, or the like. It is possible to adopt a method of displaying a stereoscopic image by causing only the left eye to enter and the right eye image GR to enter only the user's right eye.

  Alternatively, a method of displaying a stereoscopic image by superimposing the left-eye image GL and the right-eye image GR and observing the image with a polarizing glass may be used. Further, the monitor 2 may be constituted by a 3D liquid crystal and displayed by a parallax barrier method, a lenticular method, or a frame sequential method.

  The input unit 3 is configured by a pointing device such as a keyboard and a mouse, for example, and receives an instruction of shooting conditions related to the start or end of shooting or two shooting directions by the user. Here, the shooting conditions relating to the two shooting directions are desired by the user regarding the shooting angle corresponding to one of the two shooting directions and the angle formed by one shooting direction and the other shooting direction. This is a shooting condition.

  FIG. 4 is a block diagram showing a schematic configuration of the computer 4. The computer 4 includes a central processing unit (CPU) and a storage device such as a semiconductor memory, a hard disk, and an SSD. The control unit 41, the image data storage unit 42, and the display shown in FIG. A control unit 43, a transmittance storage unit 44, and an angle setting unit 45 are configured.

  The controller 41 outputs predetermined control signals to the various controllers 31 to 34 to control the entire apparatus. A specific control method will be described later.

  The image data storage unit 42 stores two image data DL and DR read out from the radiation detector 15 by radiation imaging from two different imaging directions.

  The display control unit 43 performs predetermined image processing on the image data DL and DR based on the two image data DL and DR stored in the image data storage unit 42, and then applies the left eye of the breast M to the monitor 2. The display image GL and the right eye image GR are displayed. The display control unit 43 can also display a diagnosis report and imaging conditions on the monitor 2 as necessary.

  The transmittance storage unit 44 stores the transmittance α in the grid 50 in advance in association with the shooting direction. The transmittance storage unit 44 stores in advance, in association with the transmittance α, as an imaging angle θ that is an angle between the imaging direction and a direction perpendicular to the surface 50 a of the grid 50. Here, as shown in FIG. 2, the photographing angle θ is clockwise as a positive direction and counterclockwise as a negative direction.

  Since the transmittance α for each imaging angle θ is stored in advance, as shown in FIG. 3 before imaging the breast M, radiation is directed toward the grid 50 at an imaging angle θ obtained by dividing a predetermined angle range into predetermined angles. , And the transmittance α is measured for each photographing angle θ. And the transmittance | permeability memory | storage part 44 memorize | stores the measurement result. Note that the measurement of the transmittance α at each photographing angle θ may be performed before photographing the breast M, and the measurement time is not particularly limited.

  The transmittance storage unit 44 may store the correspondence between the imaging angle θ and the transmittance α as shown in FIG. 5 as a reference table for the above measurement result, and as a function approximating the measurement result. It may be memorized. In the present embodiment, the transmittance storage unit 44 stores in advance a reference table of the transmittance α for each photographing angle θ obtained by dividing the angle range of −60 ° to + 60 ° with respect to the grid 50 in units of 2 °.

  And the grid 50 in this embodiment has the largest transmittance | permeability (alpha) in imaging | photography angle (theta) =-4 degree as shown in FIG. That is, the grid 50 has a reference position P at one point on the axis of the imaging angle θ = −4 ° that passes through the center position of the back surface of the grid 50. Further, in order to correspond to a plurality of grids having different reference positions P, the transmittance storage unit 44 can also store a plurality of the above reference tables or approximate functions for each grid identification number.

  Refer to FIGS. 2 and 4 again. The angle setting unit 45 refers to the transmittance α for each shooting angle θ stored in the transmittance storage unit 44 and sets an angle formed by two shooting directions in stereo shooting (hereinafter referred to as a convergence angle β). is there. The convergence angle β is a value obtained by subtracting the first shooting angle θ1 corresponding to one of the two shooting directions from the second shooting angle θ2 corresponding to the other shooting direction. The angle setting unit 45 sets a combination of the first shooting angle θ1 and the second shooting angle θ2.

  The angle setting unit 45 selects the first shooting angle θ1, and selects the second shooting angle θ2 having a transmittance α that is 50% or more with respect to the transmittance α of the selected first shooting angle θ1. The combination of the first shooting angle θ1 and the second shooting angle θ2 is set. Further, the angle setting unit 45 may select the second imaging angle θ2 having a transmittance α that is 80% or more with respect to the transmittance α of the selected first imaging angle θ1.

  The angle setting unit 45 receives the first imaging angle θ1 and the convergence angle β0 desired by the user by the input unit 3, and refers to the reference table stored in advance in the transmittance storage unit 44, so that the first imaging angle By extracting a shooting angle θ having a transmittance α of 50% or more with respect to the transmittance α of θ1, and combining it with the first shooting angle θ1 from the extracted shooting angles θ, the desired convergence angle β0 is obtained. The approximate shooting angle θ is selected as the second shooting angle θ2. The first imaging angle θ1 and the convergence angle β0 may be set by default. Further, the angle setting unit 45 may set the first imaging angle θ1 to 0 ° so that a radiographic image taken from one of the imaging directions can be used as a taken image for planar view.

  The angle setting unit 45 may refer to a reference table or an approximate function corresponding to the received identification number when the input unit 3 receives the identification number of the grid 50. Further, the angle setting unit 45 sets a combination of the first shooting angle θ1 and the second shooting angle θ2 so that the convergence angle β is in the range of 2 ° to 8 ° so that the user can view stereoscopically. It may be a thing.

  Next, the operation of the radiation imaging apparatus 100 will be described. FIG. 6 is a flowchart showing a series of processing by the radiation imaging apparatus 1. First, the breast M is set on the imaging table 14, and the breast M is compressed with a predetermined pressure by the compression plate 18. The input unit 3 receives the identification number of the grid 50, the first imaging angle θ1, and the convergence angle β0 desired by the user (ST1). In the present embodiment, it is assumed that the first imaging angle θ1 = 0 ° and the desired convergence angle β0 = + 5 ° are set.

  Then, when the input unit 3 receives a user's instruction to start shooting (ST2), the angle setting unit 45 receives information on the identification number, the first shooting angle θ1, and the convergence angle β0, and stores them in the transmittance storage unit 44 in advance. With reference to the stored reference table corresponding to the identification number, a shooting angle θ that is 50% or more of the transmittance α with respect to the first shooting angle θ1 is extracted (ST3).

  In the present embodiment, as shown in FIG. 5, the transmittance α = 87% at the first shooting angle θ1 = 0 °, and 67.82 with respect to the transmittance α = 87% at the first shooting angle θ1. The transmittance α being about% = θ = −12 ° and + 4 ° having about 59% = θ = −10 ° and + 2 ° having a transmittance α = 75% being about 86.21% and 100%. Θ = −8 ° with transmittance α = 87%, transmittance α = about 109.2%, θ = −95 ° with −95 °, −2 °, and transmittance α = about 114.94% A total of eight shooting angles θ of = −4 ° are extracted (ST3).

  Then, the angle setting unit 45 sets θ = + 4 ° constituting the convergence angle β = + 4 ° that is most approximate to the desired convergence angle β0 = + 5 °, out of the extracted eight shooting angles θ, as the second shooting angle. Selection is made as θ2, and a combination of the first shooting angle θ1 = 0 ° and the second shooting angle θ2 = + 4 ° is set (ST4). As described above, the convergence angle β is determined by a value obtained by subtracting the first imaging angle θ1 = 0 ° from the second imaging angle θ2 = + 4 °.

  The control unit 41 outputs the first shooting angle θ1 = 0 ° and the second shooting angle θ2 = + 4 ° to the arm controller. The arm controller 31 receives the information of the first imaging angle θ1, and outputs a control signal for the arm unit 13 to be perpendicular to the detection surface 15a as shown by the solid line in FIG. Based on the control signal, the arm unit 13 takes a posture perpendicular to the detection surface 15a.

  The control unit 41 outputs a control signal for performing radiation irradiation and reading of the image data DL of the left-eye image GL to the radiation source controller 32 and the detector controller 33. In response to this control signal, the radiation source 17 irradiates the breast M with radiation, and the grid 50 absorbs the scattered radiation scattered by the breast M and the direct line R incident on the shielding member 51 via the breast M, and the radiation. The detector 15 detects the radiation incident on the detection surface 15 a, acquires the image data DL of the left-eye image GL, and outputs it to the computer 4. The image data storage unit 42 stores the output image data DL (ST5).

  The arm controller 31 receives the information of the second imaging angle θ2, and receives a control signal that causes the arm portion 13 to be inclined by + 4 ° with respect to the vertical direction of the detection surface 15a as shown by a two-dot chain line in FIG. Output. Based on the control signal, the arm portion 13 is inclined by + 4 ° with respect to the detection surface 15a.

The control unit 41 outputs a control signal for performing radiation irradiation and reading of the image data DR of the right-eye image GR to the radiation source controller 32 and the detector controller 33. In response to this control signal, the radiation source 17 irradiates the breast M with radiation, and the grid 50 absorbs the scattered radiation scattered by the breast M and the direct line R incident on the shielding member 51 via the breast M, and the radiation. The detector 15 detects the radiation incident on the detection surface 15 a, acquires the image data DR of the right eye image GR, and outputs it to the computer 4. The image data storage unit 42 stores the image data DR (ST6). The display control unit 43 reads the image data DL and DR from the image data storage unit 42, displays the left-eye image GL and the right-eye image GR on the monitor 2 so that the user can stereoscopically view, and ends the processing ( ST7).

  According to the above embodiment, the transmittance storage unit 44 stores in advance the association between the shooting angle θ and the transmittance α as a reference table, the input unit 3 receives user instructions regarding two shooting directions, and the angle setting unit. 45 is based on the reference table and the user instruction so that the transmittance α at the second imaging angle θ2 is 50% or more with respect to the transmittance α at the first imaging angle θ1. Since the combination with the second imaging angle θ2 is set, the difference in image quality between the left-eye image GL and the right-eye image GR can be reduced.

  Further, according to the above-described embodiment, the angle setting unit 45 is configured so that the transmittance α at the second imaging angle θ2 is 80% or more with respect to the transmittance α at the first imaging angle θ1. Since the combination of the shooting angle θ1 and the second shooting angle θ2 is set, the difference in image quality between the left-eye image GL and the right-eye image GR can be further reduced.

  Further, according to the above embodiment, the input unit 3 receives the desired convergence angle β0, and the angle setting unit 45 is based on the reference table and the convergence angle β0 so as to approximate the desired convergence angle β0. Since the combination of the first imaging angle θ1 and the second imaging angle θ2 is set, the difference in image quality between the left-eye image GL and the right-eye image GR having a sense of depth desired by the user can be reduced.

  In addition, according to the above-described embodiment, the input unit 3 receives an instruction of the first shooting angle θ1, and the angle setting unit 45 is based on the reference table and the transmittance α of the specified first shooting angle θ1. In order to set a combination of the first shooting angle θ1 and the second shooting angle θ2, the left-eye image GL and the right-eye image GR shot at the first shooting angle θ1 desired by the user are set. The difference in image quality can be reduced.

  In addition, according to the above-described embodiment, the angle setting unit 45 sets the convergence angle β in the range of 2 ° to 8 °, so that the left-eye image GL and the right-eye image GR that the user can stereoscopically view are displayed. The difference in image quality can be reduced. Further, according to the above embodiment, by setting the first photographing angle θ1 to 0 °, it is possible to reduce the difference in image quality between the left-eye image GL and the right-eye image GR that can be used for planar view. . Moreover, according to said embodiment, since the grid 50 is integrated with the detection surface 15a of the radiation detector 15, the position shift with the grid 50 and the radiation detector 15 accompanying use for a long time is avoided. However, the difference in image quality between the left-eye image GL and the right-eye image GR can be reduced.

  In the above-described embodiment, the left-eye image GL is described as being captured at the first capturing angle θ1, and the right-eye image GR is captured at the second capturing angle θ2. However, the embodiment is not particularly limited. Alternatively, the right eye image GR may be captured at the first imaging angle θ1, and the left eye image GL may be captured at the second imaging angle θ2.

  In the above-described embodiment, the subject has been described as the breast M, but the subject is not particularly limited, and the subject such as the head, neck, chest, abdomen, legs, lungs or stomach is photographed. There may be.

α Transmission β Convergence angle θ Shooting angle 3 Input unit (instruction receiving unit)
17 Radiation source 15 Radiation detector 44 Transmittance storage unit 45 Angle setting unit 50 Grid 100 Radiography apparatus

Claims (9)

A radiation source that emits radiation from two different imaging directions;
A grid that absorbs a portion of the radiation emitted from the radiation source;
A radiation detector for detecting the irradiated radiation through the grid;
A transmittance storage unit that stores in advance the transmittance, which is the ratio of radiation transmitted through the grid, in association with the imaging direction;
An instruction receiving unit for receiving user instructions regarding the two shooting directions;
Based on the stored transmittance and the received user instruction, the ratio of the transmittance in the other photographing direction to the transmittance in the one photographing direction of the two photographing directions is 50% or more. A radiation imaging apparatus comprising: an angle setting unit that sets an angle formed by two imaging directions.   The angle setting unit sets an angle formed by the two shooting directions so that a ratio of the transmittance with respect to the transmittance in the one shooting direction with respect to the other shooting direction is 80% or more. The radiographic apparatus according to claim 1, wherein The instruction receiving unit receives an angle instruction from a user regarding an angle formed by the two shooting directions;
The angle setting unit sets an angle formed by the two photographing directions so as to be closest to the designated angle based on the stored transmittance and the designated angle. The radiation imaging apparatus according to claim 1 or 2. The instruction receiving unit receives an instruction of a shooting direction from a user with respect to the one shooting direction;
2. The angle setting unit is configured to set an angle formed by the two photographing directions based on the stored transmittance and the transmittance with respect to the designated one photographing direction. The radiography apparatus of any one of -3. The transmittance storage unit stores the shooting direction in advance as a shooting angle that is an angle formed by the shooting direction and a direction perpendicular to the surface of the grid,
The radiation imaging apparatus according to claim 1, wherein the imaging angle is obtained by dividing a predetermined angle range into predetermined angles.   The radiation imaging apparatus according to claim 1, wherein the angle setting unit sets an angle formed by the two imaging directions in a range of 2 ° to 8 °.   The radiation imaging apparatus according to claim 1, wherein the one imaging direction is a direction orthogonal to the surface of the grid.   The radiation imaging apparatus according to claim 1, wherein the grid is integrated with a detection surface of the radiation detector. A radiation source that emits radiation from two different imaging directions, a grid that absorbs part of the radiation emitted from the radiation source, and a radiation detection that detects a part of the emitted radiation through the grid And an operation method of a radiation imaging apparatus comprising an angle setting unit for setting an angle formed by the two imaging directions,
The transmittance storage unit stores in advance the transmittance, which is the ratio of radiation transmitted through the grid, in association with the imaging direction,
An instruction receiving unit receives user instructions regarding the two shooting directions,
The angle setting unit includes the stored transmittance and the transmission rate so that a ratio of the transmittance in the other photographing direction to the transmittance in the one photographing direction among the two photographing directions is 50% or more. An operation method of a radiation imaging apparatus, wherein an angle formed by the two imaging directions is set based on a received user instruction.

Images