Radiation diagnostic equipment

Abstract

This radiation diagnostic device comprises: a radiation detector that detects radiation; an ultraviolet source that emits ultraviolet rays; a first power provision unit that provides power to a radiation detector; and a second power provision unit that is electrically separated from the first power provision unit and that provides power to the ultraviolet source.

Description

[Technical Field]

[0001] The technology of the present disclosure relates to a radiological diagnostic apparatus. [Background technology]

[0002] Due to the recent spread of the novel coronavirus (officially known as SARS (Severe Acute Respiratory Syndrome)-Cov (Coronavirus)-2), mass infections known as clusters have occurred in medical institutions. For this reason, meticulous infection prevention measures are required for various tests and diagnoses at medical institutions. Sterilization by ultraviolet light irradiation is an effective infection prevention measure. It has also been reported that the novel coronavirus can be inactivated by exposing it to ultraviolet light for a few minutes.

[0003] As an infection prevention measure in medical institutions, it is known to provide an ultraviolet light source in a lighting device in an operating room or the like (see, for example, International Publication No. 2019 / 186880). The ultraviolet light source irradiates an area to be sterilized with ultraviolet light.

[0004] Also, in the field of radiological diagnosis using a radiation detector that detects radiological images, it is known to irradiate the radiation detector with ultraviolet light in order to sterilize the radiation detector (see, for example, Japanese Patent Application Laid-Open No. 2013-248124). Japanese Patent Application Laid-Open No. 2013-248124 describes a mobile radiological diagnostic device in which an ultraviolet light source that emits ultraviolet light toward the radiation detector is provided inside a storage folder that stores the radiation detector. Summary of the Invention [Problem to be solved by the invention]

[0005] The illumination device described in WO 2019 / 186880 includes an ultraviolet light source and an illumination light source (e.g., a halogen lamp) for illuminating the surgical field. In the illumination device described in WO 2019 / 186880, a power supply unit that supplies power to the ultraviolet light source and a power supply unit that supplies power to the illumination light source are connected in parallel. In this case, noise generated in each power supply unit may affect the ultraviolet light source and the illumination light source. However, WO 2019 / 186880 does not address the impact of noise as a problem.

[0006] In a radiological diagnostic apparatus provided with an ultraviolet light source as described in JP 2013-248124 A, when a power supply unit that supplies power to the ultraviolet light source and a power supply unit that supplies power to the radiation detector are connected in parallel as described in WO 2019 / 186880, the influence of noise becomes a problem. Because the radiation detector used in the radiological diagnostic apparatus has extremely high sensitivity to radiation detection, even if the noise generated by the power supply unit of the ultraviolet light source is very small, it may affect the radiological image detected by the radiation detector.

[0007] The technique of the present disclosure aims to provide a radiation diagnostic apparatus that can reduce the influence of noise on a radiation detector. [Means for solving the problem]

[0008] The radiation diagnostic apparatus of the present disclosure includes a radiation detector that detects radiation, an ultraviolet light source that emits ultraviolet light, a first power supply unit that supplies power to the radiation detector, and a second power supply unit that is electrically isolated from the first power supply unit and supplies power to the ultraviolet light source.

[0009] The ultraviolet light is preferably deep ultraviolet light having a central wavelength in the range of 200 nm or more and 280 nm or less.

[0010] The ultraviolet light source preferably emits ultraviolet light towards the radiation detector.

[0011] It is preferable that the radiation detector has a sensor substrate on which a plurality of pixels are formed, which generate and accumulate electric charges corresponding to the amount of incident radiation; a drive unit that inputs a drive signal to the sensor substrate to cause each of the plurality of pixels to output an electric charge; a signal processing unit that receives an electric signal corresponding to the electric charge output from the sensor substrate and generates and outputs image data based on the input electric signal; and a control unit that controls the sensor substrate, the drive unit, and the signal processing unit.

[0012] Preferably, the sensor substrate has a conversion layer that directly converts radiation into electric charges, and the first power supply unit supplies a bias voltage to the conversion layer.

[0013] The UV source is preferably an excimer lamp.

[0014] The second power supply unit preferably includes an inverter circuit.

[0015] The UV light source is preferably an LED.

[0016] It is preferable that the second power supply section supplies a pulsed driving current.

[0017] The first power supply unit and / or the second power supply unit is preferably a power supply circuit including a converter circuit that converts AC voltage into DC voltage.

[0018] It is preferable that the first power supply unit and the second power supply unit are electrically separated by a transformer having a secondary coil provided separately from the primary coil.

[0019] The reference electrode of the first power supply unit and the reference electrode of the second power supply unit are preferably electrically separated.

[0020] It is preferable that the radiation detector further comprises a radiation source that emits radiation toward the radiation detector, and a third power supply unit that is electrically isolated from the first power supply unit and the second power supply unit and supplies power to the radiation source.

[0021] The radiological diagnostic device is preferably any one of a radiological imaging device having an upright or supine imaging table, a mammography device, a radiological fluoroscopy device, a mobile radiological device, a mobile radiological fluoroscopy device, and a radiological tomography device. [Effects of the Invention]

[0022] According to the technique of the present disclosure, it is possible to provide a radiation diagnostic apparatus that can reduce the influence of noise on a radiation detector. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a diagram showing a mammography apparatus as an example of a radiation diagnostic apparatus. [Figure 2] FIG. 2 is a side view of the mammography device showing the radiation emission state. [Figure 3] FIG. 2 is a side view of the mammography device showing the irradiation state of ultraviolet light. [Figure 4] FIG. 2 is a block diagram showing the configuration of a control device. [Figure 5] FIG. 2 is a block diagram showing the configuration of a power supply device. [Figure 6] FIG. 1 is a diagram illustrating a configuration of a radiation detector. [Figure 7] FIG. 1 is a diagram showing the configuration of an ultraviolet light source. [Figure 8] FIG. 2 is a diagram showing the configuration of a radiation tube. [Figure 9] FIG. 1 is a diagram illustrating an example of a radiation imaging apparatus having an imaging table. [Figure 10] FIG. 1 is a diagram illustrating an example of a mobile radiation device. [Figure 11] FIG. 1 is a diagram illustrating an example of a radiographic imaging device. [Figure 12] FIG. 10 is a diagram illustrating another example of a radiographic imaging apparatus. [Figure 13] FIG. 1 is a diagram illustrating an example of a radiation tomography apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0024] As an example, as shown in Figures 1 and 2, a mammography device 10 performs radiography on a breast M of a subject H. The mammography device 10 irradiates the breast M with radiation R, such as X-rays or gamma rays, to generate a radiological image RI of the breast M. The mammography device 10 is an example of a "radiation diagnostic device" according to the technology of the present disclosure.

[0025] The mammography apparatus 10 comprises an apparatus main body 11 and a control device 12. The apparatus main body 11 is installed, for example, in a radiography room in a medical facility. The control device 12 is installed, for example, in a control room adjacent to the radiography room. The control device 12 is, for example, a desktop personal computer. The control device 12 is communicably connected to an image database (hereinafter abbreviated as image DB (Data Base)) server 14 via a network 13 such as a LAN (Local Area Network). The image DB server 14 is, for example, a PACS (Picture Archiving and Communication System) server, which receives radiographic images RI from the mammography apparatus 10 and stores and manages the received radiographic images RI.

[0026] A terminal device 15 is connected to the network 13. The terminal device 15 is, for example, a personal computer used by a doctor who performs medical examinations using the radiation images RI. The terminal device 15 receives the radiation images RI from the image DB server 14 and displays the received radiation images RI on a display.

[0027] The device main body 11 has a stand 20 and an arm 21. The stand 20 is composed of a base 20A placed on the floor of the radiography room and a support column 20B extending in the height direction from the base 20A. The arm 21 has a roughly C-shape when viewed from the side, and is connected to the support column 20B via a connection part 21A. This connection part 21A allows the arm 21 to move in the height direction relative to the support column 20B. In addition, the arm 21 is rotatable around a rotation axis that passes through the connection part 21A and is perpendicular to the support column 20B.

[0028] The arm 21 is composed of a radiation source housing section 22, an imaging table 23, and a main body section 24. A radiation source 25 is housed in the radiation source housing section 22. A breast M is placed on the imaging table 23. A radiation detector 26 is housed in the imaging table 23. The main body section 24 integrally connects the radiation source housing section 22 and the imaging table 23. The main body section 24 holds the radiation source housing section 22 and the imaging table 23 in opposing positions. Handrails 27 are provided on both sides of the main body section 24 for the subject H to hold onto with their hands.

[0029] The radiation source 25 is composed of a radiation tube 29 and a housing 30 that houses the radiation tube 29. The housing 30 is filled with insulating oil. The radiation tube 29 emits radiation R toward the breast M placed on the imaging table 23. The radiation detector 26 detects the radiation R that has passed through the breast M and outputs a radiographic image RI.

[0030] An irradiation field limiter 31 is provided between the radiation source housing unit 22 and the imaging table 23. The irradiation field limiter 31 is also called a collimator, and defines the irradiation field of the radiation R onto the imaging table 23.

[0031] A face guard 32 is attached to the radiation source housing 22. The face guard 32 is formed of or coated with a material that is not transparent to the radiation R, and protects the face of the subject H from the radiation R.

[0032] A compression plate 33 is attached between the imaging table 23 and the irradiation field limiter 31. The compression plate 33 is made of a material that transmits radiation R. The compression plate 33 is disposed in a position facing the imaging table 23. The compression plate 33 is movable toward the imaging table 23 and away from the imaging table 23 in response to the operation of a lift switch (not shown). The compression plate 33 moves toward the imaging table 23, and compresses the breast M by sandwiching it between the imaging table 23 and the compression plate 33.

[0033] An ultraviolet light source 34 is provided on the outer surface of the irradiation field limiter 31 facing the compression plate 33. More specifically, the ultraviolet light source 34 is provided on the outer surface of the irradiation field limiter 31 behind the face guard 32. The ultraviolet light source 34 may also be provided inside the irradiation field limiter 31.

[0034] 3, the ultraviolet light source 34 emits ultraviolet light UV toward the radiation detector 26. The ultraviolet light UV emitted from the ultraviolet light source 34 is irradiated onto the face guard 32, the compression paddle 33, etc. The ultraviolet light UV is, for example, deep ultraviolet light having a central wavelength in the range of 200 nm or more and 280 nm or less.

[0035] As the ultraviolet light source 34, an LED (Light Emitting Diode), an LD (Laser Diode), or the like can be used in addition to an ultraviolet lamp using a quartz tube. In this example, an excimer lamp, which is a type of ultraviolet lamp, is used as the ultraviolet light source 34.

[0036] The face guard 32 and the compression paddle 33 are made of a material that transmits ultraviolet light UV. An example of a material that transmits ultraviolet light UV is "CYTOP (registered trademark)" manufactured by AGC Inc. Therefore, the ultraviolet light UV enters the face guard 32 from the rear surface of the face guard 32 and irradiates the surface of the face guard 32 that faces the face of the subject H. The ultraviolet light UV also enters the compression paddle 33 from the rear surface of the compression paddle 33 and irradiates the surface of the compression paddle 33 that comes into contact with the breast M. Furthermore, the ultraviolet light UV that has passed through the compression paddle 33 irradiates the imaging table 23 on which the breast M is placed. That is, in this example, the ultraviolet light UV is mainly irradiated onto the imaging table 23, the face guard 32, and the compression paddle 33.

[0037] The imaging table 23, face guard 32, and compression plate 33 are sterilized by irradiation with ultraviolet light (UV). Here, "sterilization" by ultraviolet light (UV) means that bacteria, microorganisms, or viruses attached to the object to be irradiated are inactivated by light energy. The irradiation time of ultraviolet light (UV) required for sterilization varies depending on the irradiation energy of the ultraviolet light (UV), the distance from the ultraviolet light source 34 to the point to be irradiated with ultraviolet light (UV), and the type of bacteria or virus to be sterilized, but is approximately several minutes to several tens of minutes. For example, it has been reported that the novel coronavirus can be inactivated by irradiation with ultraviolet light (UV) for several minutes.

[0038] A power supply device 40 is provided inside the support 20B, supplying power to each component inside the apparatus main body 11. A voltage cable (not shown) extending from the power supply device 40 is disposed inside the support 20B. The voltage cable is further introduced from the connection part 21A through the arm 21 into the radiation source housing part 22, and is connected to the radiation tube 29, the radiation detector 26, the ultraviolet light source 34, etc. The power supply device 40 supplies power to the radiation tube 29, the radiation detector 26, and the ultraviolet light source 34 via the voltage cable.

[0039] A power cable 40A is connected to the power supply device 40. One end of the power cable 40A is connected to the power supply device 40, and the other end extends outside the device main body 11. The other end of the power cable 40A is connected to an external power source 70 (see FIG. 5). AC power is supplied to the power supply device 40 from the external power source 70 via the power cable 40A. The power supply device 40 has a converter circuit that converts AC to DC, a voltage stabilizing circuit that stabilizes the voltage, etc. The external power source 70 is an AC power source of a single-phase two-wire type, a single-phase three-wire type, a three-phase type, etc.

[0040] The radiation tube 29 generates radiation based on the power supplied from the power supply device 40. The radiation detector 26 performs a radiation detection operation based on the power supplied from the power supply device 40. The ultraviolet light source 34 generates ultraviolet light based on the power supplied from the power supply device 40.

[0041] As an example, as shown in FIG. 4, the computer constituting the control device 12 includes a storage 50, a memory 51, a CPU (Central Processing Unit) 52, a display 53, and an input device .

[0042] The storage 50 is a storage device such as a hard disk drive that is built into the computer that constitutes the control device 12 or that is connected via a cable or a network. The storage 50 stores control programs such as an operating system, various application programs, and various data associated with these programs.

[0043] The memory 51 is a work memory for executing processes by the CPU 52. The CPU 52 loads programs stored in the storage 50 into the memory 51 and executes processes in accordance with the programs, thereby providing overall control over each part of the computer.

[0044] The display 53 displays various screens. Operation functions are realized on the various screens using a GUI (Graphical User Interface). The computer constituting the control device 12 accepts input of operation instructions from an input device 54 via the various screens. The input device 54 is a keyboard, a mouse, a touch panel, etc.

[0045] The storage 50 stores an operating program 55. The operating program 55 is an application program for causing a computer to function as the control device 12. In addition to the operating program 55, the storage 50 also stores an irradiation condition table 56, order-specific irradiation condition information 57, and the like.

[0046] The CPU 57 of the control device 12 functions as a reception unit 60, a read / write (RW) control unit 61, a main control unit 62, an image processing unit 63, and a display control unit 64 by performing processing in cooperation with the memory 51, etc. based on the operating program 55.

[0047] The reception unit 60 receives various operation instructions input by the operator via the input device 54. For example, the reception unit 60 receives a shooting menu 65. The reception unit 60 outputs the shooting menu 65 to the RW control unit 61.

[0048] The RW control unit 61 receives the imaging menu 65 from the reception unit 60. The RW control unit 61 reads out the irradiation conditions 66 corresponding to the received imaging menu 65 from the irradiation condition table 56. The RW control unit 61 writes the irradiation conditions 66 read out from the irradiation condition table 56 into the order-specific irradiation condition information 57.

[0049] The main control unit 62 controls the power supply device 40 and the radiation detector 26. The radiation source 25 and the ultraviolet light source 34 are controlled by the main control unit 62 via the power supply device 40. The main control unit 62 reads out irradiation conditions 66 from the order-specific irradiation condition information 57. The main control unit 62 controls the power supply device 40 in accordance with the irradiation conditions 66 to operate the radiation tube 29 and cause the radiation tube 29 to emit radiation R toward the radiation detector 26. The main control unit 62 causes the radiation detector 26 to output a radiological image RI detected by the radiation detector 26 as a result of irradiation with radiation R, from the radiation detector 26 to the image processing unit 63.

[0050] The image processing unit 63 receives the radiation image RI from the radiation detector 26. The image processing unit 63 performs various image processing on the radiation image RI. The image processing unit 63 outputs the radiation image RI after the image processing to the display control unit 64. The display control unit 64 receives the radiation image RI from the image processing unit 63. The display control unit 64 displays the radiation image RI on the display 53.

[0051] The control device 12 also executes an automatic calibration operation. In the automatic calibration operation, the control device 12 acquires an offset image by reading out a signal from the radiation detector 26 when the radiation detector 26 is not irradiated with radiation R, and stores the acquired offset image in the memory 51. During radiography, the image processing unit 63 reads out the offset image from the memory 51 and performs offset correction by subtracting the offset image from the radiographic image RI detected by the radiation detector 26.

[0052] The automatic calibration operation is performed when the device main body 11 is started up or periodically at predetermined intervals. Note that irradiation of ultraviolet light UV from the ultraviolet light source 34 to the imaging table 23 may be performed during the automatic calibration operation.

[0053] 5 , the power supply device 40 is composed of a first power supply unit 41, a second power supply unit 42, a third power supply unit 43, and an isolation transformer 44. The first power supply unit 41 converts the AC voltage supplied from the external power supply 70 via the isolation transformer 44 into a DC voltage and supplies it to the radiation detector 26. The second power supply unit 42 converts the AC voltage supplied from the external power supply 70 via the isolation transformer 44 into a DC voltage and supplies it to the ultraviolet source 34. The third power supply unit 43 converts the AC voltage supplied from the external power supply 70 via the isolation transformer 44 into a DC voltage and supplies it to the radiation tube 29 included in the radiation source 25.

[0054] The isolation transformer 44 is a transformer that prevents abnormal currents and the like from flowing from the external power source 70 to the power supply device 40. The isolation transformer 44 is composed of a primary coil 45 connected to the external power source 70 and three secondary coils 46A, 46B, and 46C that are provided individually for the primary coil 45. The primary coil 45 and the three secondary coils 46A, 46B, and 46C are electrically isolated from each other. The three secondary coils 46A, 46B, and 46C are also electrically isolated from each other. Note that "electrically isolated" means that they are electrically isolated from each other. The isolation transformer 44 is an example of a "transformer" according to the technology of the present disclosure.

[0055] The first power supply unit 41 is connected to the secondary coil 46A. The second power supply unit 42 is connected to the secondary coil 46B. The third power supply unit 43 is connected to the secondary coil 46C. The first power supply unit 41, the second power supply unit 42, and the third power supply unit 43 are provided with reference electrodes 41A, 42A, and 43A, respectively, for applying a reference potential.

[0056] The reference electrode 41A of the first power supply unit 41 and the reference electrode 43A of the third power supply unit 43 are connected to, for example, a metal (hereinafter referred to as the housing metal) that constitutes the housing of the device body 11, thereby providing a ground potential. The housing metal is a metal that determines the reference potential within the device body 11.

[0057] On the other hand, the reference electrode 42A of the second power supply unit 42 is not connected to the metal housing. In this embodiment, the reference electrode 42A of the second power supply unit 42 is not connected to any metal and is in a floating state. Note that the reference electrode 42A may be connected to another metal that is electrically isolated from the metal housing to which the reference electrodes 41A and 43A are connected.

[0058] In this way, the second power supply unit 42 is electrically separated from the first power supply unit 41. In addition, the second power supply unit 42 is electrically separated from the third power supply unit 43. Therefore, electrical noise generated in the first power supply unit 41 or the third power supply unit 43 is prevented from being transmitted to the second power supply unit 42. This allows the second power supply unit 42 to supply stable power to the radiation detector 26.

[0059] The first power supply unit 41 is, for example, a power supply circuit including a converter circuit 71. The converter circuit 71 generates DC voltages having various voltage values ​​based on AC voltages supplied from an external power supply 70 via the primary coil 45 and the secondary coil 46A, and inputs the DC voltages to the radiation detector 26.

[0060] The second power supply unit 42 is, for example, a power supply circuit including a converter circuit 72 and an inverter circuit 73. The converter circuit 72 generates a DC voltage based on an AC voltage supplied from an external power supply 70 via the primary coil 45 and the secondary coil 46B, and supplies the generated DC voltage to the inverter circuit 73. The inverter circuit 73 generates a pulse-width modulated pulsed drive voltage based on the supplied DC voltage, and inputs the generated drive voltage to the ultraviolet light source 34.

[0061] The third power supply unit 43 includes, for example, a converter circuit 74 and a high-voltage generation circuit 75. The converter circuit 74 generates a DC voltage based on an AC voltage supplied from the external power supply 70 via the primary coil 45 and the secondary coil 46C, and supplies the generated DC voltage to the high-voltage generation circuit 75. The high-voltage generation circuit 75 generates a high-voltage pulse based on the supplied DC voltage, and applies the generated high-voltage pulse to the radiation tube 29.

[0062] The operations of the inverter circuit 73 and the high-voltage generating circuit 75 are controlled by the main control unit 62. The main control unit 62 controls the duty ratio of the pulsed driving voltage generated by the inverter circuit 73, thereby controlling the irradiation energy of the ultraviolet light UV generated by the ultraviolet light source 34. The main control unit 62 also controls the operation of the inverter circuit 73, thereby controlling the irradiation time of the ultraviolet light UV.

[0063] The main control unit 62 also controls the timing at which the high voltage generating circuit 75 generates a high voltage pulse, and also controls the radiation detection operation of the radiation detector 26.

[0064] 6, the radiation detector 26 includes a sensor substrate 80, a drive unit 81, a signal processing unit 82, and a sensor control unit 83. The radiation detector 26 of this embodiment is an indirect conversion type radiation detector that converts radiation into light and then converts the light into electric charges.

[0065] A scintillator 84 serving as a conversion layer is laminated on the sensor substrate 80. The scintillator 84 is made of, for example, GOS (Gd2O2:Tb) or CsI (CsI:Ti). The scintillator 84 converts radiation R emitted from the radiation source 25 and transmitted through the breast M (see FIG. 2) into light.

[0066] Photodiodes 85 as photoelectric conversion elements are arranged in a two-dimensional matrix on the sensor substrate 80. The photodiodes 85 generate electric charges in response to light converted by the scintillator 84, and accumulate the generated electric charges.

[0067] A TFT (Thin Film Transistor) 86 serving as a switching element is connected to the cathode side of the photodiode 85. The photodiode 85 is connected to a source electrode of the TFT 85. A drain electrode of the TFT 86 is connected to a signal line 87. A gate electrode of the TFT 86 is connected to a scanning line 88.

[0068] The anode side of the photodiode 85 is connected to a bias line 89. A reverse bias voltage is applied to the bias line 89 from the first power supply unit 41.

[0069] A plurality of scanning lines 88 are connected to the driving unit 81. The driving unit 81 is, for example, a gate driver. An on voltage and an off voltage are supplied to the driving unit 81 from the first power supply unit 41. The driving unit 81 switches the voltage applied to the scanning lines 88 between the on voltage and the off voltage based on a timing signal supplied from the sensor control unit 83. That is, the driving unit 81 inputs a driving signal to the sensor substrate 80 to cause each of the plurality of pixels to output a charge. The pixel is composed of a photodiode 85 and a TFT 86.

[0070] When an on-voltage is applied to the TFT 86 via the scanning line 88, the TFT 86 is turned on, thereby establishing electrical continuity between the photodiode 85 and the signal line 87. When the photodiode 85 and the signal line 87 are established, an electrical signal corresponding to the charge accumulated in the photodiode 85 is output to the signal line 87. The electrical signal output to the signal line 87 is input to the signal processing unit 82.

[0071] The signal processing unit 82 generates image data according to the electrical signals input from each of the signal lines 87 and outputs the image data as a radiographic image RI. The signal processing unit 82 is a signal processing circuit including an amplifier circuit, a correlated double sampling circuit, a multiplexer, an A / D converter, etc. An amplifier circuit and a correlated double sampling circuit are provided for each of the signal lines 87.

[0072] The sensor control unit 83 controls the operations of the drive unit 81 and the signal processing unit 82. The sensor control unit 83 is composed of, for example, a CPU, an FPGA (Field Programmable Gate Array), etc. Power is supplied to the sensor control unit 83 and the signal processing unit 82 from the first power supply unit 41. The sensor control unit 83 is an example of a "control unit" according to the technology of the present disclosure.

[0073] The drive unit 81 is formed on a drive board, and the signal processing unit 82 is formed on a signal processing board. A first power supply unit 41 supplies power to the drive board and the signal processing board. Note that part of the circuit that constitutes the drive unit 81 may be formed on the drive board. Also, part of the circuit that constitutes the signal processing board may be formed on the signal processing board.

[0074] In this embodiment, the radiation detector 26 is an indirect conversion type, but it may also be a direct conversion type. A direct conversion type radiation detector uses a conversion layer such as amorphous selenium (a-Se) that directly converts radiation into electric charges. Furthermore, a direct conversion type radiation detector is provided with a capacitor for accumulating electric charges generated by the conversion layer instead of the photodiode 85. In a direct conversion type radiation detector, a bias voltage is applied to the conversion layer from a first power supply unit 41 in a power supply device 40. That is, in a direct conversion type, the first power supply unit 41 that supplies a bias voltage to the conversion layer is electrically separated from the second power supply unit 42 that supplies a voltage to the ultraviolet light source. The other configurations are the same as those of the indirect conversion type radiation detector 26. That is, the radiation detector 26 may be any detector that has a plurality of pixels that generate and accumulate electric charges according to the amount of incident radiation R.

[0075] As an example, as shown in Figure 7, the ultraviolet light source 34 is an excimer lamp composed of a discharge vessel 90, an external electrode 91, and an internal electrode 92. The discharge vessel 90 is a double quartz tube in which a discharge space 93 is formed. The discharge space 93 is filled with discharge gas, such as xenon and chlorine. The external electrode 91 is formed, for example, of a metal mesh that transmits light.

[0076] A pulsed driving voltage is applied between the external electrode 91 and the internal electrode 92 from the second power supply unit 42. When the driving voltage is applied between the external electrode 91 and the internal electrode 92, the discharge gas in the discharge space 93 is excited, and then enters an excimer state, emitting ultraviolet rays UV when returning to the ground state.

[0077] The ultraviolet light source 34 may be an LED that emits deep ultraviolet light. When the ultraviolet light source 34 is an LED, the second power supply unit 42 generates ultraviolet light UV by supplying a pulsed driving current to the ultraviolet light source 34. That is, the LED is driven by a pulse width modulation method.

[0078] As an example, as shown in FIG. 8, the radiation tube 29 has a cathode 101 and an anode 102 housed in a substantially cylindrical vacuum glass tube 100. The cathode 101 emits electrons. The anode 102 emits radiation R when the electrons collide with it. The cathode 101 is a cold cathode. More specifically, the cathode 101 emits an electron beam EB toward the anode 102 by utilizing the field emission phenomenon. The anode 102 is a rotating anode that rotates by a rotation mechanism. Note that a fixed anode may also be used as the anode 102.

[0079] A high voltage pulse is applied as a tube voltage between the cathode 101 and the anode 102 from the third power supply unit 43. In response to the application of the high voltage pulse, an electron beam EB is emitted from the cathode 101 toward the anode 102. Then, radiation R is generated from a focal point F, which is a point on the anode 102 where the electron beam EB collides. The radiation R is emitted to the outside through an emission window 103 provided in the glass tube 100.

[0080] In the mammography apparatus 10 configured as described above, the emission of radiation R by the radiation source 25 and the detection of radiation by the radiation detector 26 are performed in conjunction with, for example, an operation signal generated by an operator operating the input device 54. The emission of ultraviolet light UV by the ultraviolet light source 34 may be performed in conjunction with an operation signal generated by an operator operating the input device 54, or may be performed periodically regardless of the operation signal. Therefore, the operating period of the radiation detector 26 and the operating period of the ultraviolet light source 34 may overlap.

[0081] Assume that noise generated in the second power supply unit 42 that supplies power to the ultraviolet light source 34 is transmitted to the first power supply unit 41 that supplies power to the radiation detector 26. In this case, even a small amount of noise may affect the radiographic image RI detected by the radiation detector 26. This is because the radiation detector 26 has extremely high detection sensitivity. However, with the technology disclosed herein, the second power supply unit 42 is electrically isolated from the first power supply unit 41, thereby reducing the influence of noise from the first power supply unit 41 on the radiation detector 26. Similarly, the second power supply unit 42 is electrically isolated from the third power supply unit 43, thereby reducing the influence of noise from the first power supply unit 41 on the radiation detector 26.

[0082] Furthermore, the ultraviolet light source 34 may operate while the radiation detector 26 is performing a calibration operation. In this case, if noise is transmitted from the first power supply unit 41 to the second power supply unit 42, the noise will affect the offset image obtained from the radiation detector 26. As a result, the noise will affect the radiation image RI after offset correction. In the technology disclosed herein, the second power supply unit 42 is electrically isolated from the first power supply unit 41, and therefore the effect of noise on the offset image due to the operation of the ultraviolet light source 34 can be reduced.

[0083] In the above embodiment, the ultraviolet light UV emitted by the ultraviolet light source 34 is deep ultraviolet light having a central wavelength in the range of 200 nm or more and 280 nm or less. It is particularly preferable that the ultraviolet light UV be deep ultraviolet light having a central wavelength of 222 nm. Deep ultraviolet light with a central wavelength of 222 nm has little effect on the human body. This is known, for example, from Japanese Patent No. 6306097. Because deep ultraviolet light with a central wavelength of 222 nm has little effect on the human body, it is possible to irradiate the ultraviolet light UV onto a subject during radiography of the subject. The technology disclosed herein is useful in a radiological diagnostic apparatus configured to irradiate ultraviolet light during radiography.

[0084] In the above embodiment, the technology of the present disclosure has been described using a mammography device as an example of a radiological diagnostic device. However, the technology of the present disclosure can also be applied to a radiological imaging device having an upright or supine imaging table, a mobile radiological imaging device, a radiological fluoroscopic imaging device, a mobile radiological fluoroscopic imaging device, or a radiological tomography imaging device, in addition to a mammography device.

[0085] Fig. 9 shows an example of a radiographic imaging apparatus having an imaging table. The radiographic imaging apparatus 10A shown in Fig. 9 includes a radiation source 25, an irradiation field limiter 31, a radiation detector 26, an ultraviolet light source 34, a power supply device 40, a supine position imaging table 110, and an upright position imaging table 120. In this example, the radiation detector 26 is a portable electronic cassette.

[0086] The supine position imaging table 110 is used when imaging the subject H in a supine position. The standing position imaging table 120 is used when imaging the subject H in an upright position. The radiation detector 26 is detachably set in the folder 111 of the supine position imaging table 110 or the folder 121 of the upright position imaging table 120.

[0087] The radiation source 25 is movable and is disposed at a position facing the radiation detector 26. Fig. 9 shows a state in which the radiation source 25 is disposed at a position facing the radiation detector 26 set in a folder 111 of the supine position imaging table 110.

[0088] The ultraviolet light source 34 is attached to, for example, the outer surface of the irradiation field limiter 31 so as to irradiate ultraviolet light UV onto the supine position imaging table 110 or the standing position imaging table 120 on which the subject H is placed.

[0089] As in the first embodiment, the power supply device 40 supplies power to the radiation source 25, the ultraviolet light source 34, and the radiation detector 26, respectively.

[0090] The radiation imaging apparatus 10A may be provided with at least one of the supine position imaging table 110 and the upright position imaging table 120.

[0091] Fig. 10 shows an example of a mobile radiation device. The mobile radiation device 10B shown in Fig. 10 is a so-called X-ray cart that is configured to be movable. The mobile radiation device 10B includes a dolly 130, a radiation source 25, an irradiation field limiter 31, a radiation detector 26, an ultraviolet light source 34, and a power supply device 40.

[0092] The dolly 130 is provided with a plurality of wheels 131 for moving the dolly 130. The dolly 130 is also provided with a handle 132 that allows an operator to move the dolly 130 by pushing or pulling the dolly 130. The dolly 130 is also provided with an operation panel 133 that allows the operator to perform various operations.

[0093] The cart 130 also has a built-in power supply device 40. The cart 130 is connected to an external power source, and power is supplied from the external power source (not shown) to the power supply device 40. The cart 130 also has a built-in battery (not shown), and power is supplied from the battery to the power supply device 40 as needed.

[0094] A support pillar 134 is erected at the front of the cart 130. The support pillar 134 is rotatable about a vertical axis. An arm 135 is attached to the support pillar 134 so as to be movable up and down. The radiation source 25 is attached to the end of the arm 135.

[0095] In this example, the radiation detector 26 is a portable electronic cassette. For example, the radiation detector 26 is placed on a bed 136. The subject H is placed in a supine position on the bed 136 so that the radiation detector 26 is located at the region to be imaged. The radiation source 25 is movable by rotating the support 134 and / or moving the arm 135 up and down, and is placed in a position facing the radiation detector 26.

[0096] The ultraviolet light source 34 is attached to, for example, the outer surface of the irradiation field limiter 31 so as to irradiate the bed 136 on which the subject H is placed with ultraviolet light UV.

[0097] As in the first embodiment, the power supply device 40 supplies power to the radiation source 25, the ultraviolet light source 34, and the radiation detector 26, respectively.

[0098] The dolly 130 is also provided with a folder 137 for storing the radiation detector 26 when not in use. The radiation detector 26 is charged, for example, in the folder 137. The ultraviolet light source 34 may be provided in the folder 137 so as to irradiate the radiation detector 26 stored in the folder 137 with ultraviolet light UV. The ultraviolet light source 34 may also be provided on the support 134, the arm 135, the dolly 130, or the like.

[0099] Fig. 11 shows an example of a radiological imaging apparatus. The radiological imaging apparatus 10C shown in Fig. 11 is a mobile radiological imaging apparatus configured to be movable. Fig. 11 also shows a C-arm digital radiological imaging apparatus as an example of the radiological imaging apparatus. The radiological imaging apparatus 10C includes a dolly 140, a radiation source 25, an irradiation field limiter 31, a radiation detector 26, an ultraviolet light source 34, and a power supply device 40.

[0100] The cart 140 is provided with a plurality of wheels 141 for moving the cart 140. A C-arm 143 is connected to the cart 140 via a support part 142. The support part 142 supports the C-arm 143 so that it can rotate freely. A radiation source 25 is provided at one end of the C-arm 143, and a radiation detector 26 is provided at the other end. The radiation detector 26 is disposed in a position facing the radiation source 25.

[0101] The cart 140 also has a built-in power supply device 40. The cart 140 is connected to an external power source, and power is supplied from the external power source (not shown) to the power supply device 40. The cart 140 also has a built-in battery (not shown), and power is supplied from the battery to the power supply device 40 as needed.

[0102] 11, the ultraviolet light source 34 is attached to the outer surface of the irradiation field limiter 31 and emits ultraviolet light UV toward the radiation detector 26. This sterilizes the radiation detector 26. Furthermore, in this example, when performing radiographic imaging (so-called over-tube type radiographic imaging) with the radiation source 25 positioned above a subject (not shown), it is possible to sterilize the subject and a bed (not shown) on which the subject is placed.

[0103] As in the first embodiment, the power supply device 40 supplies power to the radiation source 25, the ultraviolet light source 34, and the radiation detector 26, respectively.

[0104] 12 illustrates an example of radiographic imaging of subject H using the radiographic imaging apparatus 10C in the under-tube system. Subject H is placed on a bed 144. In the under-tube system, the position of the C-arm 143 is adjusted so that the radiation source 25 is located below the bed 144 and the radiation detector 26 is located above the bed 144. The radiation detector 26 creates an image of the radiation that has passed through the bed 144 and subject H.

[0105] 12, the ultraviolet light source 34 is attached to a C-arm 143, and emits ultraviolet light UV from above the subject H toward a bed 144 that is placed between the radiation source 25 and the radiation detector 26. This sterilizes the bed 144 and the subject H.

[0106] The ultraviolet light source 34 is not limited to being attached to the irradiation field limiter 31 or the C-arm 143, but may be attached to the radiation detector 26 or the dolly 140, or the like.

[0107] Although the radiographic imaging apparatus shown in FIGS. 11 and 12 is of a mobile type, the radiographic imaging apparatus may also be of a stationary type.

[0108] Fig. 13 shows an example of a radiation tomography apparatus. The radiation tomography apparatus 10D shown in Fig. 13 is a so-called CT (Computed Tomography) apparatus. The radiation tomography apparatus 10D includes a gantry 150, an imaging table 151, a radiation source 25, an irradiation field limiter 31, a radiation detector 26, an ultraviolet light source 34, and a power supply device 40.

[0109] The gantry 150 has a gantry rotating part 152. The gantry rotating part 152 has a hollow part 153 and is rotatably supported by the gantry 150. A subject (not shown) placed on an imaging table 151 is transported into the hollow part 153.

[0110] The gantry rotating unit 152 houses a radiation source 25, an irradiation field limiter 31, and a radiation detector 26. The radiation source 25 and the radiation detector 26 are arranged in opposing positions across a hollow portion 153. The radiation source 25, the irradiation field limiter 31, and the radiation detector 26 rotate together with the rotation of the gantry rotating unit 152. A tomographic image is generated by reconstructing multiple images output from the radiation detector 26.

[0111] The ultraviolet light source 34 is provided in the gantry rotating part 152 and irradiates the cavity 153 with ultraviolet light UV. Therefore, the ultraviolet light UV is irradiated onto a part of the imaging table 151 and a part of the subject H inserted into the cavity 153. In this example, the ultraviolet light source 34 rotates together with the rotation of the gantry rotating part 152. The ultraviolet light source 34 may be provided at a location other than the gantry rotating part 152 of the gantry 150, on the imaging table 151, etc.

[0112] The mammography device 10 described in the above embodiment may also have a tomosynthesis function that enables acquisition of tomographic images. In a mammography device 10 with a tomosynthesis function, a low-dose pre-imaging is performed to determine the radiation irradiation conditions for tomosynthesis imaging. During this pre-imaging, ultraviolet light UV may be irradiated by the ultraviolet light source 34. According to the technology disclosed herein, the first power supply unit 41 and the second power supply unit 42 are electrically separated, so that noise generated in the second power supply unit 42 during ultraviolet light UV irradiation is prevented from being transmitted to the first power supply unit 41. This reduces the influence of noise on the pre-imaging image obtained by the pre-imaging.

[0113] The technology of the present disclosure can be appropriately combined with the various embodiments and / or various modified examples described above. Furthermore, it is needless to say that it is not limited to the above-described embodiments, and various configurations can be adopted as long as they do not deviate from the gist of the present disclosure.

[0114] The above-described description and illustrations are a detailed explanation of the parts related to the technology of the present disclosure and are merely an example of the technology of the present disclosure. For example, the above description of the configuration, functions, actions, and effects is an explanation of an example of the configuration, functions, actions, and effects of the parts related to the technology of the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above-described description and illustrations within the scope of the gist of the technology of the present disclosure. Furthermore, to avoid confusion and facilitate understanding of the parts related to the technology of the present disclosure, the above-described description and illustrations omit explanations of common technical knowledge that do not require particular explanation to enable the implementation of the technology of the present disclosure.

[0115] In this specification, "A and / or B" is synonymous with "at least one of A and B." In other words, "A and / or B" means that it may be only A, only B, or a combination of A and B. Furthermore, in this specification, the same concept as "A and / or B" is also applied when three or more things are expressed connected by "and / or."

[0116] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. a radiation detector for detecting radiation; an ultraviolet light source that emits ultraviolet light; a first power supply unit that supplies power to the radiation detector; a second power supply electrically isolated from the first power supply and supplying power to the ultraviolet light source; A radiological diagnostic apparatus comprising: The first power supply unit and the second power supply unit are electrically separated by a transformer having a secondary coil provided separately for a primary coil. Radiological diagnostic equipment.

2. The ultraviolet light is deep ultraviolet light having a central wavelength in the range of 200 nm or more and 280 nm or less. The radiological diagnostic apparatus according to claim 1 .

3. the ultraviolet light source emits the ultraviolet light toward the radiation detector; The radiological diagnostic apparatus according to claim 1 or 2.

4. The radiation detector comprises: a sensor substrate on which a plurality of pixels are formed, which generate and accumulate electric charges according to the amount of incident radiation; a drive unit that inputs a drive signal to the sensor substrate to cause each of the plurality of pixels to output an electric charge; a signal processing unit that receives an electric signal corresponding to the charge output from the sensor substrate, generates image data based on the received electric signal, and outputs the image data; a control unit that controls the sensor substrate, the drive unit, and the signal processing unit, The radiological diagnostic apparatus according to claim 3 .

5. the sensor substrate has a conversion layer that directly converts radiation into electric charges; The first power supply supplies a bias voltage to the conversion layer. The radiological diagnostic apparatus according to claim 4.

6. The ultraviolet light source is an excimer lamp. The radiological diagnostic apparatus according to any one of claims 1 to 5.

7. the second power supply unit includes an inverter circuit; The radiological diagnostic apparatus according to claim 6.

8. The ultraviolet light source is an LED. The radiological diagnostic apparatus according to any one of claims 1 to 5.

9. a pulsed driving current is supplied from the second power supply unit; The radiological diagnostic apparatus according to claim 8.

10. the first power supply unit and / or the second power supply unit is a power supply circuit including a converter circuit that converts AC voltage into DC voltage; The radiological diagnostic apparatus according to any one of claims 1 to 9.

11. The reference electrode of the first power supply unit and the reference electrode of the second power supply unit are electrically separated. The radiological diagnostic apparatus according to any one of claims 1 to 10.

12. a radiation source that emits radiation toward the radiation detector; a third power supply unit electrically isolated from the first power supply unit and the second power supply unit and configured to supply power to the radiation source; The radiological diagnostic apparatus according to claim 1 , further comprising:

13. The radiological diagnostic device is any one of a radiological imaging device having an upright position imaging table or a supine position imaging table, a mammography device, a radiological fluoroscopy device, a mobile radiological device, a mobile radiological fluoroscopy device, and a radiological tomography device. The radiological diagnostic apparatus according to claim 12.

14. A radiation detector for detecting radiation; an ultraviolet light source that emits ultraviolet light; a first power supply unit that supplies power to the radiation detector; a second power supply electrically isolated from the first power supply and supplying power to the ultraviolet light source; A radiological diagnostic apparatus comprising: The reference electrode of the first power supply unit and the reference electrode of the second power supply unit are electrically separated. Radiological diagnostic equipment.

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