KR102399449B1 - X-ray imaging apparatus and control method for the same - Google Patents

Abstract

An X-ray imaging apparatus includes: an X-ray source for irradiating X-rays to an object; a sensor mounted on the X-ray source; and a controller for obtaining the volume of the object based on the output value of the sensor, determining the degree of obesity of the object based on the volume of the object, and adjusting the X-ray irradiation value based on the degree of obesity of the object; and, the output value of the sensor may include inclined angles of the plurality of image sensors while the X-ray source moves when the sensor includes a plurality of image sensors.
According to such an X-ray imaging apparatus and a control method therefor, it is possible to automatically detect a characteristic of an object, in particular, the degree of obesity. In addition, the intensity of X-rays may be automatically adjusted based on the detected characteristics of the object, and thus the quality of the X-ray image may be improved.

Description

X-ray imaging device and its control method

The present invention relates to an X-ray imaging apparatus for detecting characteristics of an object and a method for controlling the same.

An X-ray imaging apparatus is a device for obtaining an image inside an object by using X-rays. The X-ray imaging apparatus images the inside of the object in a non-invasive method of irradiating X-rays to the object and detecting X-rays that have passed through the object. Accordingly, the medical X-ray imaging apparatus may be used for diagnosing an internal injury or disease that cannot be confirmed from the outside.

An X-ray imaging apparatus includes an X-ray source that generates X-rays to irradiate an object, and an X-ray detector that detects X-rays that have passed through the object. According to recent automation trends, the X-ray source , and user interest in the automation of X-ray imaging devices such as X-ray detectors is also increasing.

For example, the position of the X-ray detector is automatically detected and auto tracking or auto centering is performed, the characteristics of the object are automatically detected, or the X-ray source or the X-ray detector is installed according to the detected characteristics of the object. There is a demand for automation of the X-ray imaging apparatus, such as automatically changing the position or automatically adjusting the intensity of X-rays according to the characteristics of the detected object.

Provided are an X-ray imaging apparatus for automatically detecting characteristics of an object, and a method for controlling the same.

An X-ray imaging apparatus according to one side includes: an X-ray source for irradiating X-rays to an object; a sensor mounted on the X-ray source; and a control unit configured to obtain the volume of the object based on the output value of the sensor, determine the degree of obesity of the object based on the volume of the object, and adjust the X-ray irradiation value based on the degree of obesity of the object In addition, the output value of the sensor may include inclined angles of the plurality of image sensors while the X-ray source moves when the sensor includes a plurality of image sensors.

In addition, the sensor may further include a proximity sensor.

Also, the output value of the sensor may include pixel values of images captured by the plurality of image sensors.

Also, the controller may detect an outline of the object from the image based on a change in the pixel value, and obtain a volume and a height of the object line based on the outline.

In addition, it may further include a source actuator for moving the X-ray source.

Also, when the sensor includes a proximity sensor or a plurality of image sensors, the controller may control the source actuator to move the X-ray source in a longitudinal direction of the imaging table.

Also, the output value of the sensor may include an output voltage output from the proximity sensor while the X-ray source moves.

Also, the controller may convert the output voltage into a distance from the proximity sensor, and obtain the volume of the object based on the converted distance.

In addition, the control unit obtains a first distance by converting a maximum output voltage among the output voltages, obtains a second distance by converting a minimum output voltage among the output voltages, and a difference between the first distance and the second distance The volume of the object may be obtained from

Also, the controller may obtain the key of the object from a difference between a moving distance of the X-ray source and a section in which the proximity sensor outputs a minimum output voltage among a moving distance of the X-ray source.

Also, the plurality of image sensors may have the same focus.

Also, the controller may calculate the distances from the plurality of image sensors by using Equation 3 below.

[Equation 3]

Here, d' is the distance between the plurality of image sensors, θ1 and θ2 are the inclination angles of the plurality of image sensors with respect to the focal point, and d is the distance from the plurality of image sensors to the focal point.

Also, the controller may obtain the volume of the object from a difference between a maximum distance and a minimum distance among the calculated distances.

Also, the controller may obtain the key of the object from a difference between a movement distance of the X-ray source and a section in which a minimum distance is calculated among the movement distance of the X-ray source.

In addition, the irradiation value of the X-rays may correspond to the irradiation intensity or the irradiation amount of the X-rays.

An X-ray imaging apparatus according to one side includes: an X-ray source for irradiating X-rays to an object; a table actuator for moving the imaging table; and a controller that determines the weight of the object based on the output value of the table actuator and adjusts the X-ray irradiation value based on the weight of the object.

In addition, the table actuator may include at least one of a current sensor, a magnetic sensor, and a current sensing circuit.

In addition, the output value of the table actuator may include a load current flowing on the table actuator while the imaging table moves in the vertical direction.

Also, the controller may extract a measurement current according to a sample rate from a load current flowing on the table actuator, and calculate an average current from the extracted measurement current using [Equation 2].

[Equation 2]

Here, Xi (i=1, 2, ..., n)) is the extracted measurement current, n is the number of times it is extracted, and Xrms is the average current.

Also, the controller may determine the degree of obesity of the object by comparing the load current with at least one preset current reference value.

Also, the controller may determine the weight of the object based on the load current, compare the determined weight of the object with at least one preset weight reference value, and determine the degree of obesity of the object.

An X-ray imaging apparatus according to one side includes: an X-ray source for irradiating X-rays to an object; a sensor mounted on the X-ray source; a table actuator for moving the imaging table; and a control unit configured to obtain the height of the object based on the output value of the sensor, obtain the weight of the object based on the output value of the table actuator, and adjust the X-ray irradiation value based on the height and weight of the object may include

According to one aspect, a control method of an X-ray imaging apparatus includes: acquiring a volume of an object based on an output value of a sensor mounted on an X-ray source; determining the degree of obesity of the subject based on the volume of the subject; and adjusting an irradiation value of X-rays irradiated from the X-ray source based on the degree of obesity of the object, wherein the output value of the sensor is when the sensor includes a plurality of image sensors, the X-ray source moves while, the inclined angles of the plurality of image sensors may be included.

A method of controlling an X-ray imaging apparatus according to one side includes: moving an imaging table in a vertical direction; determining the weight of the object based on an output value of the table actuator according to the movement of the photographing table; and adjusting an irradiation value of X-rays irradiated from an X-ray source based on the weight of the object.

According to one aspect, a method of controlling an X-ray imaging apparatus includes: acquiring a key of an object based on an output value of a sensor mounted on an X-ray source; acquiring the weight of the object based on an output value of a table actuator that moves the imaging table; The method may include adjusting an irradiation value of X-rays irradiated from the X-ray source based on the height and weight of the object.

1 is a perspective view illustrating an external appearance of an X-ray imaging apparatus.
2 is an exploded perspective view showing an X-ray imaging apparatus disassembled.
3 is a perspective view illustrating an operation unit of the X-ray imaging apparatus.
4 is a control block diagram of an X-ray imaging apparatus according to an exemplary embodiment.
5 is a cross-sectional view illustrating an internal structure of an X-ray tube.
6 is a schematic diagram schematically showing the structure of a sensing panel.
7 is a graph showing the relationship between energy and an attenuation coefficient for each material inside an object.
8 is a view for explaining the attenuation phenomenon according to the thickness of fat.
9 is a configuration diagram of a table actuator according to an embodiment.
10 is a block diagram of a table actuator according to another embodiment.
11 is a block diagram of a table actuator according to another embodiment.
12 is a diagram for explaining a method of calculating an average current.
13 and 14 are diagrams for explaining the determination of the degree of obesity according to the current reference value.
15 is a control block diagram of an X-ray imaging apparatus according to another exemplary embodiment.
16 is a diagram for describing distance sensing by a proximity sensor.
17 is a diagram for describing a method of detecting a height and volume of an object using an output value of a proximity sensor.
18 is a diagram for explaining image acquisition by a single image sensor.
19 is a diagram for describing a method of detecting a height and volume of an object using an output value of an image sensor.
20 is a diagram for explaining distance sensing by a plurality of image sensors.
21 is a diagram for explaining a method of detecting a height and volume of an object using output values of a plurality of image sensors.
22 is a control block diagram of an X-ray imaging apparatus according to another exemplary embodiment.
23 is a flowchart of a method of controlling an X-ray imaging apparatus according to an exemplary embodiment.
24 is a flowchart of a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.
25 is a flowchart of a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.
26 is a flowchart of a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.

The configuration shown in the embodiments and drawings described in this specification is only a preferred example of the disclosed invention, and there may be various modifications that can replace the embodiments and drawings of the present specification at the time of filing of the present application.

Hereinafter, an X-ray imaging apparatus and a control method thereof will be described in detail according to the embodiments described below with reference to the accompanying drawings. In the drawings, like reference numerals denote like elements.

1 is a perspective view illustrating an external appearance of an X-ray imaging apparatus, and FIG. 2 is an exploded perspective view illustrating the X-ray imaging apparatus in an exploded manner.

1 to 2 , the X-ray imaging apparatus 100 includes a guide rail 30 , a movable carriage 40 , a photo frame 50 , an actuator 110 , 114 , 115 , and an X-ray source 70 . , the X-ray detector 100 , a manipulation unit 80 , and a workstation 170 may be included. The X-ray imaging apparatus 100 may further include an imaging table 10 and an imaging stand 20 on which the X-ray detector 90 can be mounted.

The guide rail 30 , the moving carriage 40 , the post frame 50 , etc. are provided to move the X-ray source 70 toward the object.

The guide rail 30 includes a first guide rail 31 and a second guide rail 32 installed to form a predetermined angle with each other. It is preferable that the first guide rail 31 and the second guide rail 32 extend in a direction perpendicular to each other.

The first guide rail 31 is installed on the ceiling of the examination room in which the radiographic imaging apparatus is disposed. The second guide rail 32 is positioned below the first guide rail 31 and is slidably mounted on the first guide rail 31 . A roller (not shown) movable along the first guide rail 31 may be installed on the first guide rail 31 . The second guide rail 32 is connected to this roller (not shown) and can move along the first guide rail 31 .

A first direction D1 is defined in a direction in which the first guide rail 31 extends, and a second direction D2 is defined in a direction in which the second guide rail 32 extends. Accordingly, the first direction D1 and the second direction D2 may be orthogonal to each other and may be parallel to the ceiling of the examination room.

The moving carriage 40 is disposed below the second guide rail 32 to be movable along the second guide rail 32 . A roller (not shown) provided to move along the second guide rail 32 may be installed in the moving carriage 40 . Accordingly, the moving carriage 40 is movable in the first direction D1 together with the second guide rail 32 and is movable in the second direction D2 along the second guide rail 32 . The post frame 50 is fixed to the moving carriage 40 and located below the moving carriage 40 . The post frame 50 may include a plurality of posts 51 , 52 , 53 , 54 and 55 .

The plurality of posts 51 , 52 , 53 , 54 , 55 are connected to each other to be foldable so that the post frame 50 may increase or decrease in length in the vertical direction of the examination room while being fixed to the moving carriage 40 .

A third direction D3 is defined in a direction in which the length of the post frame 50 increases or decreases. Accordingly, the third direction D3 may be orthogonal to the first direction D1 and the second direction D2 .

The X-ray source 70 is a device that radiates X-rays to an object.

Here, the object may be a living body of a person or an animal, but is not limited thereto, and may be an object as long as its internal structure can be imaged by the X-ray imaging apparatus 1 . However, for convenience of explanation, the subject is a human being and will be described in detail below.

The X-ray source 70 may include an X-ray tube 71 that generates X-rays, and a collimator 72 that guides the generated X-rays toward the object, and a detailed description of the X-ray tube will be described later.

A rotation joint 60 is disposed between the X-ray source 70 and the post frame 50 .

The rotation joint 60 couples the X-ray source 70 to the post frame 50 and supports a load applied to the X-ray source 70 . The rotation joint 60 may include a first rotation joint 61 connected to the lower post 51 of the post frame 50 and a second rotation joint 62 connected to the X-ray source 70 .

The first rotation joint 61 is provided to be rotatable about the central axis of the post frame 50 extending in the vertical direction of the examination room. Accordingly, the first rotation joint 61 may rotate on a plane perpendicular to the third direction D3. At this time, the rotation direction of the first rotation joint 61 may be newly defined, and the newly defined fourth direction D4 is the rotation direction of the shaft parallel to the third direction D3.

The second rotation joint 62 is provided to be rotatable on a plane perpendicular to the ceiling of the examination room. Accordingly, the second rotation joint 62 may rotate in a rotation direction of an axis parallel to the first direction D1 or the second direction D2. At this time, the rotation direction of the second rotation joint 62 may be newly defined, and the newly defined fifth direction D5 is the rotation direction of the shaft extending in the first direction or the second direction. The X-ray source 70 may be connected to the rotation joint 60 to rotate in the fourth direction D4 and the fifth direction D5 . In addition, the X-ray source 70 is connected to the post frame 50 by the rotation joint 60 to move linearly in the first direction D1 , the second direction D2 , and the third direction D3 .

Actuators 110 , 114 , and 115 may be provided to move the X-ray source 70 in the first direction D1 to the fifth direction D5 . The actuators 110 , 114 , and 115 may include a motor and a motor driver for driving the motor, and the motor may be an electrically driven electric motor.

The actuators 110 , 114 , and 115 may include first, second, third, fourth, and fifth actuators 111 , 112 , 113 , 114 , and 115 corresponding to each direction.

Each of the actuators 111 , 112 , 113 , 114 , and 115 may be disposed in various positions in consideration of design convenience. For example, the first actuator 111 for moving the second guide rail 32 in the first direction D1 is disposed around the first guide rail 31 and moves the moving carriage 40 in the second direction. The second actuator 112 for moving is disposed around the second guide rail 32, and the third actuator 113 for increasing or decreasing the length of the post frame 50 in the third direction D3 is the moving carriage ( 40) can be placed inside. And, the fourth actuator 114 for rotationally moving the X-ray source 70 in the fourth direction D4 is disposed around the first rotation joint 61 and moves the X-ray source 70 in the fifth direction D5. The fifth actuator 115 for rotationally moving may be disposed around the second rotation joint 62 .

Here, the first actuator 111 , the second actuator 112 , and the third actuator 113 for moving the moving carriage 40 will be hereinafter defined as the carriage actuator 110 .

Each actuator 111 , 112 , 113 , 114 , 115 is to be connected to a power transmission means (not shown) to move the X-ray source 70 in a straight line or rotation in the first direction D1 to the fifth direction D5. can The power transmission means (not shown) may be generally used belts and pulleys, chains and sprockets, shafts, and the like.

A manipulation unit 80 providing a user interface is provided on one side of the X-ray source 70 . Here, the user is a person who diagnoses an object using the X-ray imaging apparatus 100 and may be a medical staff including a doctor, a radiologist, a nurse, etc., but is not limited thereto. If it is, it is assumed that all users can be users.

3 is a perspective view illustrating an operation unit of the X-ray imaging apparatus.

As shown in FIG. 3 , the operation unit 80 may include a button 83 and a display panel 81 , and the user presses the button 83 or touches the display panel 81 in a manner such as, Various information regarding X-ray imaging may be input or each device may be operated. The display panel 81 includes a cathode ray tube (CRT), a digital light processing (DLP) panel, a plasma display panel, a liquid crystal display (LCD) panel, and electroluminescence. (Electro Luminescence: EL) panel, Electrophoretic Display (EPD) panel, Electrochromic Display (ECD) panel, Light Emitting Diode (LED) panel, or Organic Light Emitting Diode: OLED) may be provided as a panel, but is not limited thereto.

In addition, the manipulation unit 80 includes a handle 82 so that the user can grip it. That is, the user grips the handle 82 of the manipulation unit 80 and applies a force or torque to linearly move the X-ray source 70 in the first direction D1 to the third direction D3, or the fourth direction. (D4) and the fifth direction (D5) can be rotated. Although the handle 82 is illustrated in FIG. 3 as being provided at the lower part of the manipulation unit 80 , it is also possible to be provided at another position of the manipulation unit 80 .

The manipulation unit 80 may include a central processing unit (CPU), a graphic processing unit (GPU), and various types of storage devices implemented with a microprocessor or the like, and such devices are built-in It may be provided on a printed circuit board (PCB). Since the manipulation unit 80 includes a printed circuit board and is provided on one side of the X-ray source 70, it may be referred to as a “Tube Head Board” or “THU”.

Referring back to FIG. 1 , the workstation 170 includes an input unit 171 and a display unit 172 , and provides a user interface together with the manipulation unit 80 . Accordingly, the user may input various types of information regarding X-ray imaging through the workstation 170 or may operate respective devices. For example, the user may set the imaging conditions according to the imaging part through the workstation 170 , or input a command to move the moving carriage 40 or the X-ray source 70 , or a command to start X-ray imaging. . Also, the user may check images obtained during the X-ray imaging process through the workstation 170 .

The input unit 171 may include a hardware input device such as various buttons or switches, a keyboard, a mouse, a track-ball, various levers, a handle or a stick for user input. can The input unit 210 may be provided above the workstation 170 as shown in FIG. 1 , but when the input unit 210 is implemented as a foot switch or a foot pedal, the work It is also possible to be provided under the station 170 .

The input unit 171 may include a graphical user interface (GUI) such as a touch pad for user input, that is, an input device that is software.

The touch pad may be implemented as a touch screen panel (TSP) to form a layer structure with the second display unit 172 to be described later.

Like the display panel 81 of the manipulation unit 80 , the display unit 172 includes a cathode ray tube (CRT), a digital light processing (DLP) panel, a plasma display panel, and liquid crystal. Display (Liquid Crystal Display: LCD) Panel, Electro Luminescence (EL) Panel, Electrophoretic Display (EPD) Panel, Electrochromic Display (ECD) Panel, Light Emitting Diode (LED) ) panel or an organic light emitting diode (OLED) panel, but is not limited thereto.

As described above, when the touch screen panel (TSP) forms a layer structure with the touch pad, the display unit 172 may be used as an input device in addition to the display device.

In addition, the workstation 170 includes a printed circuit board including various processing units and various types of storage devices, such as a central processing unit (CPU) or a graphic processing unit (GPU). ; PCB) may be built-in. Accordingly, the workstation 170 accommodates the main components of the X-ray imaging apparatus 1, for example, the controller (500 in FIG. 4 ) to perform various judgments for the operation of the X-ray imaging apparatus 1, or to perform various controls signal can be generated.

A blocking film (B) is provided between the workstation 170 and the examination room to block X-rays, so that even while X-ray imaging is in progress, the user can input information or use the device while not exposed to X-rays through the blocking film (B). can be manipulated.

The X-ray detector 90 is a device that detects X-rays that have passed through an object.

The X-ray detector 90 may be mounted on the imaging table 10 or the imaging stand 20 during X-ray imaging. A table mounting unit 15 for mounting the X-ray detector 90 is provided on the imaging table 10 , and the table mounting unit 15 is provided to be movable in the longitudinal direction of the imaging table 10 . Similarly, the stand mounting unit 25 for mounting the X-ray detector 90 is provided on the imaging stand 20 , and the stand mounting unit 25 is provided to be movable in the longitudinal direction of the imaging stand 20 . In this case, the longitudinal direction of the imaging table 10 may be defined as the sixth direction D6 and the longitudinal direction of the imaging stand 20 may be defined as the seventh direction D7 , respectively. The table mounting unit 15 or the stand mounting unit 25 on which the X-ray detector 90 is mounted moves along the sixth direction D6 or the seventh direction D7 to photograph the whole or a specific part of the object.

The photographing table 10 supports the photographing table 10 and includes a support 12 for adjusting the height of the photographing table 10, and the support 12 includes a table actuator to move the support 12 in the vertical direction. (refer to 200 of FIG. 4 ) may be provided. In this case, the vertical direction of the support 12 will be defined as the eighth direction D8, and a detailed description of the table actuator will be described later.

The external appearance of the X-ray imaging apparatus has been described above. Hereinafter, the configuration of the X-ray imaging apparatus 100 for detecting the degree of obesity and the role of each component will be described in detail below.

4 is a control block diagram of an X-ray imaging apparatus according to an exemplary embodiment.

Referring to FIG. 4 , the X-ray imaging apparatus 101 according to an exemplary embodiment includes a power unit 180 , an X-ray source 70 , an X-ray detector 90 , a table actuator 200 , a control unit 500 , and a storage unit 550 . ), an input unit 171 , and a display unit 172 .

The power supply unit 180 receives external power or internal power to supply power to each component of the X-ray imaging apparatus 10 such as the X-ray source 70 and the X-ray detector 90 . The power supply unit 180 supplies power required for operation of each component in the form of current, and the form of current may be DC current or AC current.

The X-ray source 70 is a device that generates X-rays and irradiates them to an object, and may include an X-ray tube 71 as shown in FIG. 5 for generating X-rays. 5 is a cross-sectional view illustrating an internal structure of an X-ray tube.

The X-ray tube 71 may be implemented as a dipole vacuum tube including an anode 71c and a cathode 71e, and the tube body may be a glass tube 71a made of hard silicate glass or the like.

The cathode 71e includes a filament 71h and a focusing electrode 71g for focusing electrons, and the focusing electrode 71g is also referred to as a focusing cup. The inside of the glass tube 71a is made into a high vacuum state of about 10 mmHg, and the filament 71h of the cathode is heated to a high temperature to generate hot electrons. As an example of the filament 71h, a tungsten filament may be used, and a current may be applied to the electric conductor 71f connected to the filament to heat the filament 71h. However, the disclosed embodiment is not limited to employing the filament 71h for the negative electrode 71e, and it is also possible to use a carbon nano-tube that can be driven by a high-speed pulse as the negative electrode.

The anode 71c is mainly made of copper, and a target material 71d is applied or disposed on the side facing the cathode 71e, and the target material includes a high-resistance material such as Cr, Fe, Co, Ni, W or Mo. can be used The higher the melting point of the target material, the smaller the focal spot size.

When a high voltage is applied between the cathode 71e and the anode 71c, hot electrons are accelerated and collide with the target material 71d of the anode to generate X-rays. The generated X-rays are irradiated to the outside through the window 71i, and a beryllium (Be) thin film may be used as a material of the window.

The target material 71d may be rotated by the rotor 71b, and when the target material 71d is rotated, the heat accumulation rate may be increased 10 times or more per unit area compared to the case where the target material 71d is fixed, and the focal size is reduced. .

A voltage applied between the cathode 71e and the anode 71c of the X-ray tube 71 is referred to as a tube voltage, and its magnitude may be expressed as a crest value kvp. When the tube voltage is increased, the speed of the hot electrons is increased, and as a result, the energy of the X-rays (energy of the photons) generated by colliding with the target material is increased. The current flowing through the X-ray tube 71 is referred to as a tube current and can be expressed as an average value of mA. As the tube current increases, the X-ray dose (number of photons) increases. That is, the energy of the X-rays may be controlled by the tube voltage, and the dose of the X-rays may be controlled by the tube current.

The X-ray detector 90 is a device that detects X-rays that are irradiated from the X-ray source 70 and have passed through the object, and the detection of these X-rays is performed by the sensing panel 120 inside the X-ray detector 90 . Also, the sensing panel 120 converts the detected X-rays into electrical signals to obtain an X-ray image inside the object.

The sensing panel 120 may be classified according to a material composition method, a method for converting detected X-rays into an electrical signal, and a method for obtaining an electrical signal.

First, the sensing panel 120 is divided into a case in which a single-type element is configured and a case in which a hybrid-type element is configured according to a material composition method.

In the case of being composed of a single device, the part that detects X-rays and generates an electrical signal and the part that reads and processes the electrical signal are made of a single material semiconductor or are manufactured in a single process, for example, light-receiving This is a case of using a single CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) device.

In the case of being composed of a hybrid device, a part that detects X-rays to generate an electrical signal and a part that reads and processes an electrical signal are made of different materials or manufactured by different processes. For example, when X-rays are detected using a light receiving element such as a photodiode, CCD, or CdZnTe and electrical signals are read and processed using CMOS Read Out Integrated Circuit (ROIC), X-rays are detected using a strip detector and CMOS There are cases where an electrical signal is read and processed using ROIC, and a case where an a-Si or a-Se flat panel system is used.

In addition, the sensing panel 120 is divided into a direct conversion method and an indirect conversion method according to a method of converting X-rays into electrical signals.

In the direct conversion method, when X-rays are irradiated, an electron-hole pair is temporarily generated inside the light receiving element, and the electrons move to the anode and the holes move to the cathode by the electric field applied to both ends of the light receiving element, the sensing panel 120 This movement is converted into an electrical signal. Materials used for the light receiving element in the direct conversion method include a-Se, CdZnTe, HgI2, PbI2, and the like.

In the indirect conversion method, when X-rays irradiated from the X-ray source 70 react with a scintillator to emit photons having a wavelength in the visible light region, the light receiving element detects this and converts it into an electrical signal. In the indirect conversion method, a material used as a light receiving element is a-Si, etc., and as a scintillator, a thin film type GADOX scintillator, micro-pillar type or needle structure type CSI(T1), etc. are used.

In addition, according to a method of acquiring an electrical signal, the sensing panel 120 stores electric charges for a certain time and then acquires a signal from the charge integration mode (Charge Integration Mode) and whenever a signal is generated by a single X-ray photon. It is divided into a photon counting mode that counts.

The sensing panel 120 is applicable to any of the above-described methods. Also, the sensing panel 120 may have a two-dimensional array structure including a plurality of pixels 150 .

6 is a schematic diagram schematically showing the structure of a sensing panel.

Referring to FIG. 6 , the sensing panel 120 may include a light receiving element 121 that detects X-rays and generates an electrical signal, and a readout circuit 122 that reads out the generated electrical signal.

A single crystal semiconductor material may be used as the light receiving element 121 to secure high resolution, fast response time, and high dynamic range at low energy and low dose. etc.

The light receiving element 121 may form a PIN photodiode type in which a p-type semiconductor substrate 121c having a two-dimensional array structure is bonded to a lower portion of a high-resistance n-type semiconductor substrate 121b.

The read circuit 122 using a complementary metal oxide semiconductor (CMOS) process may form a two-dimensional array structure and may be combined with the p-type substrate 121c of the light receiving element 121 for each pixel 150 . In this case, as the bonding method, a flip-chip bonding method in which bumps 123 such as solder (PbSn) or indium (In) are formed and then reflowed, heated, and compressed may be used.

The intensity of the X-rays irradiated from the X-ray source 70 is attenuated by scattering or absorption while passing through the object, and accordingly, the X-ray detector 90 detects the attenuated X-rays. The degree of attenuation of X-rays varies depending on the material constituting the object and the energy level of the X-ray. As such, the attenuation coefficient ( attenuation coefficient).

7 is a graph showing the relationship between energy and an attenuation coefficient for each material inside an object.

Referring to FIG. 7 , the attenuation coefficient varies depending on the constituent material inside the object. The curve indicating the damping coefficient of bone is located above the curve indicating the damping coefficient of soft tissue (muscle, fat), and when X-rays of the same energy level, for example, E1 are irradiated, the damping coefficient of bone (B1) is the muscle It is larger than the damping coefficient (M1) of the muscle, and the damping coefficient (M1) of the muscle is larger than the damping coefficient (F1) of the fat. That is, different materials inside the object have different damping coefficients, and the harder the material, the higher the damping coefficient.

The attenuation coefficient varies depending on the energy level of the X-rays to be irradiated, and the difference in the attenuation coefficient between materials also varies depending on the energy level of the X-rays. In the graph of FIG. 4 , when X-rays of energy levels E1 and E2 are respectively irradiated to a bone object, the attenuation coefficient B1 at E1 with a low energy level is higher than the attenuation coefficient B2 at E2 with a high energy level. big. Even when the constituent material of the object is muscle or fat, the attenuation coefficients (M1, F1) when E1 with a low energy level is irradiated is greater than the attenuation coefficients (M2, F2) when E2 with a high energy level is irradiated each can be checked. That is, as the energy level of the X-rays irradiated to the object 35 decreases, the attenuation coefficient increases.

As expressed in Equation 1 below, the degree of attenuation of X-rays may vary depending on the thickness of the object or the thickness of each material constituting the object.

Here, I0 is the intensity of X-rays irradiated to the material, I is the intensity of X-rays that have passed through the material, and μ(E) is the attenuation coefficient of the material with respect to X-rays having energy E. T is the thickness of the material through which X-rays are transmitted.

According to [Equation 1], even if the attenuation coefficient is the same, as the thickness of the material increases, the degree of attenuation of X-rays increases. In other words, even when X-rays are irradiated to the same material with the same intensity and energy level, the intensity of the transmitted X-rays decreases as the thickness of the material increases.

8 is a view for explaining the attenuation phenomenon according to the thickness of fat.

Specifically, the left diagram of FIG. 8 shows that X-rays are irradiated to a subject having a normal amount of fat, and the right diagram of FIG. 8 shows that X-rays are irradiated to a subject having a higher fat amount than normal (ie, obese). As described above, the thicker the material, the greater the degree of attenuation of X-rays, and the greater the thickness or amount of fat (that is, the higher the degree of obesity), the greater the thickness or amount of fat even when comparing the constituent materials of the object, for example, fat. strength is decreased.

The degree of obesity described below refers to the amount, thickness, or ratio of substances constituting a target site to be photographed by irradiating X-rays. As described above, the X-ray image obtained through the X-ray imaging apparatus 102 only when the X-ray irradiation value is adjusted according to the ratio of fat, bone, muscle, etc. constituting the target site to be photographed by irradiating the X-ray. quality can be improved. Accordingly, the X-ray imaging apparatus 102 according to the disclosed embodiment may determine the degree of obesity and adjust the X-ray irradiation value according to the determination result. A detailed description thereof will be provided later. In the drawing of FIG. 8 , when the X-ray source 70 irradiates X-rays with the same intensity and energy level, the object on the right side rather than the object on the left (ie, the object with normal fat amount) A lot of scattering or absorption of X-rays occurs with respect to (that is, an obese object), and accordingly, the X-ray detector 90 that detects transmitted X-rays detects X-rays of lower intensity on the right side. In other words, the greater the degree of obesity of the object, the smaller the intensity of X-rays detected by the X-ray detector, and accordingly, the quality of the X-ray image obtained through the X-ray imaging apparatus 100 may also decrease. Therefore, The controller 500 controls the X-ray source 70 to increase the intensity of X-rays as the degree of obesity of the object increases. Prior to this, the table actuator 200 may operate to determine the degree of obesity of the object.

The table actuator 200 drives the table motor (see 213 in FIG. 9, 223 in FIG. 10, and 233 in FIG. 10) according to the control signal of the controller 500, and moves the imaging table 10 in the eighth direction (D8). ) to move The table actuator 200 measures the current flowing through the table actuator 200 while the imaging table 10 moves in the eighth direction, and transmits the measured current to the controller 500 . The table actuator 200 measures and transmits a current according to the existence of the object and the weight of the object (ie, according to the degree of load applied to the table actuator 200 ).

9 is a configuration diagram of a table actuator according to an embodiment.

Referring to FIG. 9 , the table actuator 210 may include a motor driver 212 , a table motor 213 , a resistor 211 , an amplifier 214 , and an Analog to Digital Converter (ADC) 215 . there is.

The motor driver 212 receives power from the power supply unit 180 to drive the table motor 213 . Resistors R and 211 may be provided between the power supply unit 180 and the motor driver 212 , and in this case, the resistors R and 211 may be a sensing resistor or a shunt resistor. . The amplifier 214 is connected to both ends of the resistors R and 211 to measure the voltage difference between both ends of the resistors R and 211 or the current Im flowing through the resistors R and 211, and amplify it. The ADC 215 converts the analog current signal received from the amplifier 214 into a digital current signal and transmits it to the controller 500 .

Meanwhile, the voltage difference between both ends of the resistors R and 211 or the current Im flowing through the resistors R and 211 may be measured using an external measuring device. According to an embodiment, the external measuring device includes a device capable of measuring voltage, current, etc., such as a multimeter, but is not limited to one embodiment, and all devices capable of measuring a voltage difference or current includes

10 is a block diagram of a table actuator according to another embodiment.

Referring to FIG. 10 , the table actuator 220 may include a motor driver 222 , a table motor 223 , a magnetic field sensor 221 , and an analog to digital converter (ADC) 225 .

The motor driver 222 receives power from the power supply unit 180 to drive the table motor 223 . A magnetic field sensor 221 may be provided between the power supply unit 180 and the motor driver 222 , and in this case, the magnetic field sensor 221 may be a hall sensor. The magnetic field sensor 221 may detect a voltage according to the magnetic flux and, accordingly, detect a current Im flowing through the motor driver 222 . The ADC 225 converts the analog current signal received from the magnetic field sensor 221 into a digital current signal and transmits it to the controller 500 .

11 is a block diagram of a table actuator according to another embodiment.

Referring to FIG. 11 , the table actuator 230 may include a motor driver 222 and a table motor 233 . In this case, a current sensor and ADC are provided in the motor driver 222 itself, or a current sensing circuit including the current sensor and ADC is provided.

However, the configuration of the table actuator 200 described above with reference to FIGS. 9, 10 and 11 is merely an example, and when the table motor is driven, if only the current flowing through the table actuator 200 can be measured, the table actuator ( 200) may have other configuration diagrams, but is not limited thereto.

The table actuator 200 measures the current while moving the imaging table 10 in the eighth direction D8 in a state in which an object is present (ie, under load). In this way, the current measured in the state in which the object is present (ie, under load) may be referred to as the on-load current, and in response to the current under load, the current measured on the imaging table ( The current measured according to the movement of 10) can be defined as the no-load current.

The controller 500 controls the overall operation of the X-ray imaging apparatus 101 .

The controller 500 controls the operation of each component of the X-ray imaging apparatus 101 , such as the X-ray source 70 , the X-ray detector 90 , the table actuator 200 , the storage 550 , and the display 172 .

The controller 500 may generate a control signal for measuring the current and transmit it to the table actuator 200 . The controller 500 may receive the current measured by the table actuator 200 and determine the degree of obesity of the object by using the received current.

The control unit 500 may calculate the current received from the table actuator 200 as an average current, and use this to determine the degree of obesity of the object.

12 is a diagram for explaining a method of calculating an average current.

The motor drivers 212, 222, and 223 receive power to drive the table motors 213, 223, and 233. At this time, the analog current flowing on the table actuator 200 is shown in FIG. 12(a). It may have a graph form as illustrated. When the table motors 213 , 223 , and 233 are driven, an inrush current may be detected.

In order to reduce the error caused by the starting current, the control unit 500 may determine the degree of obesity using the current measured after a predetermined time point, but as shown in FIG. 12(b) or FIG. 12(c) Similarly, the current measured during the predetermined time region T may be used.

Specifically, the analog current shown in FIG. 12 (a) is converted into a digital current as shown in FIG. 12 (b) through the ADC of the table actuator 200 and transmitted to the controller 500 can be That is, the ADC may transmit the measured current extracted according to a predetermined sample rate to the controller 500 .

The control unit 500 may calculate the average current of the measured currents extracted for a predetermined time region T based on the time T0 when the table motors 213 , 223 , and 233 are driven, and when the average current is calculated The following [Equation 2] can be used.

Here, Xi (i=1, 2, ..., n)) is the extracted measured current, n is the number of times it is extracted, and Xrms is the average current.

로 산출할 수 있다.제어부(500)가 평균전류를 산출하는 경우, 전술한 부하시 전류는 부하시의 측정전류에 대한 평균전류를, 그리고 무 부하시 전류는 무 부하시의 측정전류에 대한 평균전류를 각각 의미하는 것으로 한다. As illustrated in (c) of FIG. 12 , during the preset time period T, the extraction points of the measurement current according to the sample rate are referred to as T1, T2, T3, and T4, and at the time points T1, T2, T3, and T4 When the correspondingly extracted measured currents are X1, X2, X3, and X4, the control unit 500 calculates the average current Xrms by using [Equation 2].

When the control unit 500 calculates the average current, the above-described current under load is the average current with respect to the measured current at the time of load, and the current at no load is the average of the measured current at no load. Let it mean each current.

Meanwhile, the method for the control unit 500 to calculate the average current is not limited by the above-described method. For example, when the extracted measured currents are arranged in order of magnitude, the control unit 500 may calculate the median value located in the middle as the average current, and calculate the most extracted mode among the extracted measured currents as the average current As another example, when at least one of the extracted measured currents is greater than or less than a preset level compared to other measured currents, the controller 500 determines this to be an error and excludes it when calculating the average current. As another example, in calculating the average current, the measured current value having the minimum value and the measured current value having the maximum value among the extracted measured currents are determined as errors and the average current may be calculated. In addition, the control unit 500 may calculate the average current through various averaging methods, but is not limited to the above-described method.

The controller 500 determines the degree of obesity of the object by using the measured or calculated load-time current. The controller 500 may determine the degree of obesity of the object by comparing the current under load with a preset current reference value, and compare the weight of the object calculated from the current under load with a preset weight reference value to determine the degree of obesity of the object may judge. In this case, the current reference value means a current value corresponding to a reference weight for determining the degree of obesity, and at least one current reference value may be preset and stored in the storage unit 550 . Similarly, at least one weight reference value may be preset and stored in the storage unit 550 .

13 and 14 are diagrams for explaining the determination of the degree of obesity according to the current reference value.

As illustrated in FIG. 13 , a single current reference value P may be set. The single current reference value P is a current value corresponding to a reference weight (eg, 130 kg) that can be determined, and is set to be larger than the no-load current. Accordingly, the control unit 500 compares the current under load with the current reference value P, and when the current under load is equal to or greater than the current reference value P, determines that the subject is obese. In the case of FIG. 13 , since the current under load has a higher value than the current reference value P, the controller 500 determines that the object is obese.

A plurality of current reference values may be set. The plurality of current reference values are current values corresponding to a plurality of reference weights (eg, 130 kg, 140 kg, 150 kg), and are set to be larger than the no-load current, and the control unit 500 controls a plurality of current reference values that are increased in stages. It can be used to determine the degree of obesity of the subject.

The current reference value may be set differently according to the moving direction of the imaging table 10 .

The graph on the left of FIG. 14 shows the no-load current and the under-load current measured (or calculated) according to the weight of the object when the imaging table 10 moves in the direction opposite to the gravity direction, that is, in the up direction. The graph on the right of FIG. 14 shows the no-load current and the under-load current measured (or calculated) according to the weight of the object when the imaging table 10 moves in the direction of gravity, that is, the down direction. . Here, the current when the weight becomes 0 is the no-load current, and the current when the weight is large is the current under load.

Due to gravity, the table actuator 200 receives a greater load when the imaging table 10 moves in the up direction than when the imaging table 10 moves in the down direction, and the amount of current consumption increases. Accordingly, the no-load current is also measured (or calculated) higher when moving in the up direction, and the slope of the graph also forms a steep shape when moving in the up direction.

Accordingly, even if the reference weight W is the same, the reference current P1 when the imaging table 10 moves in the up direction and the reference current P2 when the imaging table 10 moves in the down direction may be set differently. That is, the current reference value P1 when moving in the up direction may be set higher than the current reference value P2 when moving in the down direction.

On the other hand, the photographing table 10 may be equipped with a motor for moving in the horizontal direction. Accordingly, the imaging table 10 can be moved in the horizontal direction by the motor. When the photographing table 10 moves in the horizontal direction, since the weight and the load are proportional, the degree of obesity can be determined based on the consumption of current. In this case, the current reference value P3 when the imaging table 10 moves in the horizontal direction may be set differently from the current reference value P1 when the imaging table 10 moves in the upward direction and the current reference value P2 when the imaging table 10 moves in the downward direction.

Also, the controller 500 may determine the degree of obesity of the object by comparing the weight of the object calculated from the current under load with a preset weight reference value. To this end, the storage unit 550 may store at least one reference weight value and the graph of FIG. 14 , that is, the relationship between weight and current in the form of data.

Specifically, the controller 500 calculates the current under load as the weight of the object by using the relationship between the weight and the current, and compares the calculated weight with a single weight reference value (eg, 130 kg) to the degree of obesity of the object or by comparing the calculated weight with a plurality of weight reference values (eg, 130 kg, 140 kg, 150 kg) that increase stepwise to determine the degree of obesity of the subject.

Meanwhile, an acceleration sensor may be mounted on the imaging table 10 or the X-ray detector 90 . When the imaging table 10 moves in the horizontal direction, the upward direction, or the downward direction, the instantaneous acceleration of the imaging table 10 is different according to the weight of the object. Also, even if the imaging table 10 moves in the same direction and the motor operates with the same power, the heavier the weight of the object, the smaller the instantaneous acceleration. That is, the weight of the object and the instantaneous acceleration of the imaging table 10 are inversely proportional to each other. Accordingly, the controller 500 may measure the instantaneous acceleration of the imaging table 10 through the acceleration sensor, and determine the degree of obesity of the object based on the measurement. Data on the instantaneous acceleration according to the weight of the object may be calculated in advance for each direction and stored in the storage unit 550 . The control unit 500 may calculate a weight corresponding to the measured instantaneous acceleration by using the data stored in the storage unit 550 .

The controller 500 may adjust the intensity of X-rays irradiated from the X-ray source 70 by adjusting the tube voltage or tube current of the X-ray tube 71 based on the determination of the degree of obesity. The X-ray irradiation value to be described below means an X-ray irradiation amount or irradiation intensity.

The controller 500 controls the X-ray source 70 so that an X-ray of greater intensity is irradiated to an obese object than an object having a normal fat amount. The controller 500 controls the X-ray source 70 so that the higher the degree of obesity of the object, the greater the intensity of X-ray irradiation. In this case, the intensity of X-ray irradiation for each of the subject having normal fat amount and the obese subject may be preset and stored for each imaging region, and similarly, the X-ray irradiation value for each imaging region is preset according to the degree of obesity of the object. and may be stored.

The controller 500 receives the detected X-rays from the X-ray detector 90 and generates a projection image of the object, that is, an X-ray image according to the intensity of the received X-rays.

The generated X-ray image may be displayed through the display unit 172 . Since the irradiation value of X-rays is adjusted according to the degree of obesity of the object, the quality of the image displayed through the display unit 172 may be improved.

The storage unit 550 stores data and programs for the operation of the X-ray imaging apparatus 101 .

For example, the storage unit 550 may store at least one preset current reference value in order to determine the comparison between the on-load current and the current reference value. Alternatively, in order to determine the comparison between the current under load and the weight reference value, the storage unit 550 provides the graph of FIG. 14 , that is, the relationship graph between the weight and the current when the imaging table 10 moves in the up direction A graph of the relationship between weight and current when the imaging table 10 moves in the down direction may be stored in the form of data, respectively. The storage unit 550 may store the X-ray irradiation intensity for each of the subject having at least one preset weight reference value and the amount of normal fat and the obese object for each imaging region, and X-ray irradiation for each imaging region according to the degree of obesity of the object. You can also save the intensity. In addition, the storage unit 550 may store a program for determining the degree of obesity based on the current reference value or a program for determining the degree of obesity based on the weight reference value. Such a storage unit 550 is a flash memory type. (flash memory type), hard disk type (hard disk type), multimedia card micro type, card type memory (such as SD or XD memory), Random Access Memory (RAM), At least one type of static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, magnetic disk, or optical disk may include a storage medium of However, the present invention is not limited thereto, and may be implemented in any other form known in the art. In addition, the home appliance 100 may operate a web storage that performs a storage function on the Internet. On the other hand, the storage unit 550 includes the degree of obesity predicted through the above-described program and the target object. The actual obesity degree of the person can be stored. Accordingly, the controller 500 may update the program by performing a process of correcting an error by comparing a result predicted through the program with the actual state of the object. The controller 500 according to the disclosed embodiment may more accurately determine the degree of obesity of the subject by continuously updating the program.

15 is a control block diagram of an X-ray imaging apparatus according to another exemplary embodiment.

Referring to FIG. 15 , the X-ray imaging apparatus 102 includes a power supply unit 180 , an X-ray source 70 , an X-ray detector 90 , a carriage actuator 110 , a sensor 300 , a control unit 500 , and a storage unit 550 . ), an input unit 171 , and a display unit 172 . In describing the components of the X-ray imaging apparatus 102 according to another embodiment, the same elements as those described above will be omitted below.

The sensor 300 may be mounted on the X-ray source 70 to detect a distance from the X-ray source 70 to the object or to acquire an image of the object. The sensor 300 may include at least one of a proximity sensor and an image sensor.

For example, the sensor 300 may be provided as a proximity sensor (refer to S1 of FIG. 16 ) to detect a distance between the X-ray source 70 and the object. In this case, the proximity sensor S1 may be provided in the form of an ultrasonic sensor, an optical sensor (eg, an infrared sensor, a PSD sensor, a CCD sensor, etc.) or an RF sensor.

For example, the X-ray imaging apparatus 102 may detect a distance between the X-ray source 70 and the object by adjusting the angle of the proximity sensor SI. As another example, when the proximity sensor SI is mounted on the X-ray source 70 , the X-ray imaging apparatus 102 may detect a distance between the X-ray source 70 and the object according to the movement of the X-ray source 70 . can

16 is a diagram for describing distance sensing by a proximity sensor.

Referring to FIG. 16 , the proximity sensor S1 may be mounted near the lower end of the X-ray source 70 , for example, near the collimator 72 . The X-ray source 70 moves in the longitudinal direction of the imaging table 10 according to a control signal from the controller 500, and the proximity sensor S1 moves the imaging table 10 or the object (S1) while the X-ray source 70 moves. to detect the distance to ob). The output value of the proximity sensor S1 according to the distance is transmitted to the control unit 500 , and the control unit 500 detects the height and volume of the object by using it, and determines the degree of obesity of the object.

17 is a diagram for describing a method of detecting a height and volume of an object using an output value of a proximity sensor.

The upper graph of FIG. 17 shows the output voltage of the proximity sensor S1 according to the distance. When an object exists within a predetermined distance Pd from the proximity sensor S1, the output voltage of the proximity sensor S1 increases rapidly as the distance from the object increases. On the other hand, when the distance between the object and the proximity sensor S1 is out of the predetermined distance Pd, the output voltage of the proximity sensor S1 decreases as the distance from the object increases. That is, the output voltage of the proximity sensor S1 rapidly increases in proportion to the distance to the object within the predetermined distance Pd, but decreases in inverse proportion to the distance to the object after the predetermined distance Pd. Therefore, the X-ray source 70 and the proximity sensor S1 are set so that the distance from the object ob is greater than the predetermined distance Pd, and the object ob is set using a graph after the predetermined distance Pd, that is, a graph of inverse proportion. The height and volume of (ob) can be detected.

The proximity sensor S1 transmits an output voltage output while the X-ray source 70 moves to the controller 500 , and the shape of the output voltage may be as illustrated in the lower graph of FIG. 17 . As described above, since the output voltage of the proximity sensor S1 is inversely proportional to the distance, it is greatest in the vicinity of the abdomen of the object ob and maintains the smallest value in the vicinity where the imaging table 10 is located.

Accordingly, the controller 500 converts the largest output voltage into a distance from the object according to the upper graph of FIG. 17 , and converts the smallest output voltage into a distance from the imaging table 10 , and converts the difference between the converted values into the object (ob) The abdominal thickness is obtained. In this case, the obtained abdominal thickness may be the volume V of the object. Also, in the lower graph of FIG. 17 , the control unit 500 obtains the key H of the object ob by excluding both ends that maintain the smallest output voltage.

The controller 500 determines the degree of obesity of the object ob by using the obtained volume V and height H. The method for determining the degree of obesity according to the volume (V) and the height (H) may use a known technique, and a detailed description thereof will be omitted.

When the sensor 300 is provided as the proximity sensor S1, the control unit 500 generates a control signal for driving the carriage actuator 110, and according to the driving of the carriage actuator 110, the X-ray source 70 is It moves in the longitudinal direction of the photographing table 10 . The carriage actuator 110 is for movement of the X-ray source 70 and may be referred to as a source actuator 110 hereinafter. In addition, the storage unit 550 may store the relationship between the output voltage and the distance in the form of data as shown in the upper graph of FIG. can

The sensor 300 may be provided as an image sensor such as a camera, and may detect a distance between objects or acquire an image of the object. The sensor 300 may be provided as at least one image sensor. For example, the sensor 300 may be provided as a single image sensor (refer to S2 of FIG. 18 ) to acquire an image of an object. Also, the sensor 300 may be provided with a plurality of image sensors (refer to S21 and S22 of FIG. 20 ) to detect a distance between the objects.

18 is a diagram for explaining image acquisition by a single image sensor. Referring to FIG. 18 , the image sensor S2 may be mounted singly at the lower end of the X-ray source 70 , for example, near the collimator 72 , and acquires an image from the upper portion of the object. That is, an upper image of the object is acquired. The output value of the image sensor S2 is transmitted to the control unit 500 , and the control unit 500 detects the height and volume of the object by using it, and determines the degree of obesity of the object.

19 is a diagram for explaining a method of detecting a height and volume of an object using an output value of an image sensor.

The image sensor S1 may acquire an upper image of the object as illustrated in FIG. 19 . The output value of the image sensor S1 becomes the pixel value Px of the image, and the pixel value Px of the image is sharp at the boundary between the portion in which the object exists and the portion in which the object does not exist, that is, the outline Po of the object. change drastically Accordingly, the controller 500 detects the outline Po of the object from the change in the pixel value Px, and the abdominal width V of the object ob and the height H of the object based on the detected outline Po. ) is obtained. In this case, the obtained abdominal width V may be the volume of the object. The controller 500 determines the degree of obesity of the object ob by using the obtained volume V and height H.

When the sensor 300 is provided as a single image sensor S2, the storage 550 stores a pixel value Px of an image acquired by the image sensor S2 or an image output by the image sensor S2 as data. form, and using this, a program for detecting the outline Po of the object, a program for obtaining the volume V and the key H from the detected outline Po, and the like can be stored.

20 is a diagram for explaining distance sensing by a plurality of image sensors.

Referring to FIG. 20 , the plurality of image sensors S21 and S22 may be mounted at a lower end of the X-ray source 70 , for example, near the collimator 72 . Angles of the plurality of image sensors S21 and S22 may be adjusted to have the same focus (eg, focus F). The X-ray source 70 moves in the longitudinal direction of the imaging table 10 according to the control signal of the controller 500 , and the plurality of sensors S21 and S22 move the X-ray source 70 according to the movement of the imaging table 10 . Alternatively, the focus F is moved on the surface of the object ob. While the focus F moves, the output values of the image sensors S21 and S22 are transmitted to the control unit 500 , and the control unit 500 calculates the distance to the imaging table 10 or the object ob using this. In this case, the output value of the image sensors S21 and S22 may be an angle with respect to the focus F. In addition, the controller 500 detects the height and volume of the object from the calculated distance, and determines the degree of obesity of the object.

21 is a diagram for explaining a method of detecting a height and volume of an object using output values of a plurality of image sensors.

As shown in the upper side of FIG. 21 , the distance between the two image sensors S21 and S22 is d', and the output values (ie, angles) of the image sensors S21 and S22 with respect to the focus F are θ1 and θ2, respectively. , the distance d from the image sensors S21 and S22 to the object may be expressed as in [Equation 3] below.

The controller 500 may calculate the distance d from the image sensors S21 and S22 to the imaging table 10 or the object ob by using the output values of the image sensors S21 and S22 and [Equation 3]. there is.

As described above, the plurality of image sensors S21 and S22 move the focus F while the X-ray source 70 moves and transmit an output value to the controller 500 . The control unit 500 calculates a distance d from the image sensor S21. S22 to the imaging table 10 or the object ob in response to the movement position of the focus F, and the form of the calculated distance d is shown in the lower side of FIG. It may be as illustrated in the graph. That is, the distance d from the image sensors S21 and S22 has the smallest value in the vicinity of the abdomen of the object ob, and maintains the largest value in the vicinity where the imaging table 10 is located.

Accordingly, the controller 500 obtains the difference between the largest value and the smallest value among the distances d from the image sensors S21 and S22 as the abdominal thickness of the object ob. In this case, the obtained abdominal thickness may be the volume V of the object. In addition, the control unit 500 excludes both ends maintaining the largest value in the lower graph of FIG. 21 to obtain the key H of the object ob. The controller 500 determines the degree of obesity of the object ob by using the obtained volume V and height H.

When the sensor 300 is provided with a plurality of image sensors S21 and S22 , the control unit 500 generates a control signal for driving the carriage actuator (or the source actuator, 110 ), and drives the carriage actuator 110 . Accordingly, the X-ray source 70 moves in the longitudinal direction of the imaging table 10 . Also, the storage unit 550 may store the distance d' between the image sensors S21 and S22, and based on the output value of the image sensors S21 and S22, the distance from the image sensors S21 and S22 ( A program for calculating d) and a program for obtaining a volume V and a key H using the calculated distance d may be stored.

In the above, it is illustrated that the sensor 300 includes only the proximity sensor or includes only the image sensor through FIGS. 16 to 21 , but the present invention is not limited thereto, and it is also possible to provide a mixture of the proximity sensor and the image sensor. .

22 is a control block diagram of an X-ray imaging apparatus according to another exemplary embodiment.

Referring to FIG. 22 , the X-ray imaging apparatus 103 includes a power supply unit 180 , an X-ray source 70 , an X-ray detector 90 , a table actuator 200 , a carriage actuator 110 , a sensor 300 , and a control unit 500 . ), a storage unit 550 , an input unit 171 , and a display unit 172 . In describing the components of the X-ray imaging apparatus 103 according to another embodiment, the same elements as those of the X-ray imaging apparatus of FIG. 4 or 16 will be omitted below.

The sensor 300 is mounted on the X-ray source 70 and may include at least one of a proximity sensor and an image sensor. The sensor 300 may include only a proximity sensor, an image sensor, or a mixture of a proximity sensor and an image sensor. Also, when the sensor 300 includes an image sensor, at least one image sensor may be provided.

When the sensor 300 includes a proximity sensor or a plurality of image sensors, the controller 300 controls the driving of the carriage actuator 110 , and the X-ray source 70 moves according to the driving of the carriage actuator 110 . During (ie, while the X-ray source 70 moves in the longitudinal direction of the imaging table 10), the output values of the proximity sensor or the plurality of image sensors are transmitted.

When the sensor 300 includes a single image sensor, the controller 300 drives the carriage actuator 110 so that the X-ray source 70 is positioned above the object, and receives an output value of the single image sensor.

The controller 300 detects the height and volume of the object by using the output value of the sensor 300 .

When the control unit 500 receives the output voltage of the proximity sensor, according to the upper graph of FIG. 17 , the largest output voltage is converted into a distance to the object, and the smallest output voltage is converted to a distance from the imaging table (10), , a difference between the converted values is obtained as the abdominal thickness (or volume V) of the object ob. Also, in the lower graph of FIG. 17 , the control unit 500 obtains the key H of the object ob by excluding both ends that maintain the smallest output voltage.

When the controller 500 receives the pixel value Px of the image from the image sensor, it detects the outline Po of the object from the change in the pixel value Px, and based on the detected outline Po, the object ob ) to obtain a volume (V) and a height (H) of

When the controller 500 receives the angle of the image sensor, it calculates the distance to the imaging table 10 or the object ob by using [Equation 3], and the largest and smallest values among the calculated distances. is obtained as the abdominal thickness (or volume V) of the subject ob. In addition, the control unit 500 excludes both ends maintaining the largest value in the lower graph of FIG. 21 to obtain the key H of the object ob.

The control unit 500 generates a control signal for driving the table actuator 200, and the table actuator 200 moves the imaging table 10 in the eighth direction D8 according to the control signal of the control unit 500, Measure the current under load. The controller 500 receives the current under load, and calculates the current under load as the weight (W) of the object using the graph of the relationship between weight and current shown in FIG. 14 .

As another example, the control unit 500 detects a voltage or current that is proportional to the weight (W) of the object using a piezoelectric sensor, and can calculate the weight (W) of the object by using the detection result. Through this, the weight (W) of the object may be calculated.

The controller 500 determines the degree of obesity of the object by using the obtained volume (V), height (H), and weight (W) of the object. The method for determining the degree of obesity according to the volume (V), the height (H) and the weight (W) may use a known technique, and a detailed description thereof will be omitted.

Based on the determination of the degree of obesity, the controller 500 may adjust the irradiation value of the X-rays irradiated from the X-ray source 70 by adjusting the tube voltage or tube current of the X-ray tube 71 .

The above has been described based on the control block diagram exemplified for the X-ray imaging apparatus for detecting the degree of obesity of an object. Hereinafter, a control method of the X-ray imaging apparatus will be described with reference to the given flowchart.

23 is a flowchart of a method of controlling an X-ray imaging apparatus according to an exemplary embodiment.

Referring to FIG. 23 , first, the table actuator 200 drives the table motor according to the control signal, and measures the current under load flowing through the table actuator 200 when the table motor is driven ( 711 ).

In a state in which an object is present on the imaging table 10 , the table motor is driven according to a control signal of the controller 500 , and by driving the table motor, the imaging table 10 moves in the eighth direction D8 , that is, up ) direction or moving downward. The table actuator 200 includes a current sensor, a magnetic sensor, or a current sensing circuit, etc. to measure and measure the current (ie, current under load) flowing through the table actuator 200 while the imaging table 10 is moving. The current under load is transmitted to the control unit 500 .

The controller 500 compares the current under load with at least one preset current reference value to determine the degree of obesity of the object ( 712 ).

The controller 500 may convert the received load-time current into an average current form. In addition, when a single current reference value is set, the control unit 500 may determine the degree of obesity of the object by comparing the current under load with the single current reference value, and when a plurality of current reference values are set, the control unit ( 500) may determine the degree of obesity of the object by comparing the current under load with a plurality of reference current values.

The control unit 500 adjusts the irradiation intensity of X-rays to be irradiated by the X-ray source 70 on the basis of the determination of the degree of obesity (713).

When it is determined that the object is obese, the controller 500 controls to be irradiated with X-rays of greater intensity than the object having a normal fat amount. In addition, the controller 500 controls so that the higher the degree of obesity of the object, the greater the intensity of X-ray irradiation. In this case, the X-ray irradiation intensity for each of the subject having normal fat amount and the obese subject may be preset and stored for each imaging region. and may be stored.

24 is a flowchart of a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.

Referring to FIG. 24 , first, the table actuator 200 drives the table motor according to the control signal, and measures the load current flowing through the table actuator 200 when the table motor is driven ( 721 ). Since step 721 is the same as step 711, a description thereof will be omitted.

Next, the controller 500 calculates the weight of the object from the current under load ( 722 ).

The controller 500 may convert the received load-time current into an average current form. Also, the controller 500 calculates the current under load as the weight (W) of the object using the graph of the relationship between the weight and the current shown in FIG. 14 . When the imaging table 10 moves in the upward direction in step 721, the control unit 500 calculates the weight W of the object using the left graph of FIG. 14, and in step 721 the imaging table 10 When moving in the downward direction, the controller 500 calculates the weight W of the object using the graph on the right of FIG. 14 .

The controller 500 compares the calculated weight of the object with at least one preset weight reference value to determine the degree of obesity of the object ( 723 ).

When a single weight reference value (eg, 130 kg) is set, the controller 500 may compare the calculated weight with the single weight reference value to determine the degree of obesity of the subject, and a plurality of weight reference values (eg, For example, when 130 kg, 140 kg, 150 kg) is set, the controller 500 may determine the degree of obesity of the object by comparing the calculated weight with a plurality of weight reference values that increase in stages.

The control unit 500 adjusts the irradiation intensity of X-rays to be irradiated by the X-ray source 70 based on the determination of the degree of obesity ( 724 ). Since step 724 is the same as step 713 described above, a description thereof will be omitted.

25 is a flowchart of a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.

Referring to FIG. 25 , first, the controller 500 controls the carriage actuator 110 to adjust the position of the X-ray source ( 731 ).

When the sensor 300 mounted on the X-ray source 70 includes a proximity sensor or a plurality of image sensors, the controller 500 determines that the moving carriage 40 and the X-ray source 70 connected thereto are connected to the imaging table 10 . ) to control the driving of the carriage actuator 110 to move in the longitudinal direction. While the X-ray source 70 moves, the output value of the sensor 300 , that is, the output voltage of the proximity sensor or the angle of the image sensor is transmitted to the controller 500 .

When the sensor 300 includes a single image sensor, the control unit 500 controls the carriage actuator 110 so that the moving carriage 40 and the X-ray source 70 connected thereto are located above the object, and the sensor The output value of 300 , that is, the pixel value Px of the image is transmitted to the controller 500 .

The controller 500 detects the volume and height of the object from the output value of the sensor 300 (operation 732 ).

When the control unit 500 receives the output voltage of the proximity sensor, the largest output voltage and the smallest output voltage are converted into a distance to the object ob and a distance to the imaging table 10, respectively, according to the upper graph of FIG. 17 . and the difference between the converted values is obtained as the abdominal thickness (or volume V) of the subject ob. Also, in the lower graph of FIG. 17 , the control unit 500 obtains the key H of the object ob by excluding both ends that maintain the smallest output voltage.

When the controller 500 receives the pixel value Px of the image from the image sensor, it detects the outline Po of the object from the change in the pixel value Px, and based on the detected outline Po, the object ob ) to obtain the volume (V) and height (H) of the object.

When the controller 500 receives the angle of the image sensor, it calculates the distance to the imaging table 10 or the object ob by using [Equation 3], and the largest and smallest values among the calculated distances. is obtained as the abdominal thickness (or volume V) of the subject ob. In addition, the control unit 500 excludes both ends maintaining the largest value in the lower graph of FIG. 21 to obtain the key H of the object ob.

The controller 500 determines the degree of obesity of the object by using the object's volume and height (733). In addition, the control unit 500 adjusts the irradiation intensity of X-rays to be irradiated by the X-ray source 70 based on the determination of the degree of obesity ( 734 ).

26 is a flowchart illustrating a method of controlling an X-ray imaging apparatus according to another exemplary embodiment.

Referring to FIG. 26 , first, the table actuator 200 drives the table motor according to the control signal, and measures the load current flowing through the table actuator 200 when the table motor is driven ( 741 ). Also, the control unit 500 calculates the weight of the object from the current under load ( 742 ). Steps 741 and 742 correspond to steps 721 and 722, respectively.

The controller 500 controls the carriage actuator 110 to adjust the position of the X-ray source ( 743 ). Also, the controller 500 detects the volume and height of the object from the output value of the sensor 300 (S744). Steps 743 and 744 correspond to steps 731 and 732, respectively, and steps 743 and 744 may be located before step 741 .

The controller 500 determines the degree of obesity of the object by using the volume, height, and weight of the object ( 745 ). In addition, the control unit 500 adjusts the irradiation intensity of X-rays to be irradiated by the X-ray source 70 based on the determination of the degree of obesity ( 746 ).

Although embodiments of the X-ray imaging apparatus and the control method of the X-ray imaging apparatus have been described with reference to the drawings exemplified as described above, those of ordinary skill in the art to which the present invention pertains to the technical idea or essential features of the present invention It will be understood that the present invention may be embodied in other specific forms without changing the . Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100, 101, 102, 103: X-ray imaging device
70: X-ray source 90: X-ray detector
110: carriage actuator 200: table actuator
300: sensor 500: control unit
550: storage

Claims (25)

an X-ray source irradiating X-rays to the object;
a sensor mounted on the X-ray source; and
a controller for obtaining the volume of the object based on the output value of the sensor, determining the degree of obesity of the object based on the volume of the object, and adjusting the X-ray irradiation value based on the degree of obesity of the object;
including,
The sensor includes a plurality of image sensors,
The output value of the sensor is
An X-ray imaging apparatus including inclined angles of the plurality of image sensors while the X-ray source moves. The method of claim 1,
The sensor is
An X-ray imaging device further comprising a proximity sensor. The method of claim 1,
The output value of the sensor is
An X-ray imaging apparatus including pixel values of images photographed by the plurality of image sensors. 4. The method of claim 3,
The control unit is
The X-ray imaging apparatus detects an outline of the object from the image based on a change in the pixel value, and obtains a volume and a height of the object based on the outline. The method of claim 1,
a source actuator for moving the X-ray source;
An X-ray imaging device further comprising a. 6. The method of claim 5,
The control unit is
When the sensor includes a proximity sensor or a plurality of image sensors, the X-ray imaging apparatus controls the source actuator to move the X-ray source in the longitudinal direction of the imaging table. ◈Claim 7 was abandoned at the time of payment of the registration fee.◈ 7. The method of claim 6,
The output value of the sensor is
An X-ray imaging apparatus including an output voltage output from a proximity sensor while the X-ray source moves. ◈Claim 8 was abandoned when paying the registration fee.◈ 8. The method of claim 7,
The control unit is
The X-ray imaging apparatus converts the output voltage into a distance from the proximity sensor, and obtains the volume of the object based on the converted distance. ◈Claim 9 was abandoned at the time of payment of the registration fee.◈ 9. The method of claim 8,
The control unit is
A first distance is obtained by converting a maximum output voltage among the output voltages, a second distance is obtained by converting a minimum output voltage among the output voltages, and the volume of the object is obtained from the difference between the first distance and the second distance X-ray imaging device to acquire. ◈Claim 10 was abandoned when paying the registration fee.◈ 8. The method of claim 7,
The control unit is
The X-ray imaging apparatus obtains the key of the object from a difference between a moving distance of the X-ray source and a section in which the proximity sensor outputs a minimum output voltage among a moving distance of the X-ray source. The method of claim 1,
The plurality of image sensors,
X-ray imaging devices having the same focus. ◈Claim 12 was abandoned when paying the registration fee.◈ The method of claim 1,
The control unit is
An X-ray imaging apparatus for calculating distances from the plurality of image sensors by using the following [Equation 3].
[Equation 3]

Here, d' is the distance between the plurality of image sensors, θ1 and θ2 are the inclination angles of the plurality of image sensors with respect to the focal point, and d is the distance from the plurality of image sensors to the focal point. ◈Claim 13 was abandoned when paying the registration fee.◈ 13. The method of claim 12,
The control unit is
An X-ray imaging apparatus for acquiring the volume of the object from a difference between a maximum distance and a minimum distance among the calculated distances. ◈Claim 14 was abandoned at the time of payment of the registration fee.◈ 13. The method of claim 12,
The control unit is
An X-ray imaging apparatus for obtaining the key of the object from a difference between a movement distance of the X-ray source and a section in which a minimum distance is calculated among the movement distance of the X-ray source. ◈Claim 15 was abandoned when paying the registration fee.◈ According to claim 1,
The X-ray irradiation value is,
An X-ray imaging apparatus corresponding to an irradiation intensity or an irradiation amount of the X-rays. According to claim 1,
Table actuator for moving the photographing table; further comprising,
The control unit is
The X-ray imaging apparatus determines the weight of the object based on the output value of the table actuator, and further adjusts the X-ray irradiation value based on the weight of the object. ◈Claim 17 was abandoned when paying the registration fee.◈ 17. The method of claim 16,
The table actuator is
An X-ray imaging apparatus comprising at least one of a current sensor, a magnetic sensor, and a current sensing circuit. ◈Claim 18 was abandoned when paying the registration fee.◈ 18. The method of claim 17,
The output value of the table actuator is
An X-ray imaging apparatus including a load current flowing on the table actuator while the imaging table moves in the vertical direction. an X-ray source irradiating X-rays to the object;
a table actuator for moving the imaging table; and
A control unit that determines the weight of the object based on the output value of the table actuator and adjusts the X-ray irradiation value based on the weight of the object;
The control unit is
An X-ray imaging apparatus for extracting a measurement current from a load current flowing on the table actuator according to a sample rate, and calculating an average current from the extracted measurement current using [Equation 2].
[Equation 2]

Here, Xi (i=1, 2, ..., n)) is the extracted measurement current, n is the number of times it is extracted, and Xrms is the average current. ◈Claim 20 was abandoned when paying the registration fee.◈ 19. The method of claim 18,
The control unit is
An X-ray imaging apparatus for determining the degree of obesity of the object by comparing the load current with at least one preset current reference value. ◈Claim 21 has been abandoned at the time of payment of the registration fee.◈ 19. The method of claim 18,
The control unit is
The X-ray imaging apparatus determines the degree of obesity of the object by determining the weight of the object based on the load current, and comparing the determined weight of the object with at least one preset weight reference value. According to claim 1,
Table actuator for moving the photographing table; further comprising,
The control unit is
X-ray for obtaining the height of the object based on the output value of the sensor, obtaining the weight of the object based on the output value of the table actuator, and adjusting the irradiation value of the X-rays further based on the height and weight of the object shooting device. ◈Claim 23 was abandoned at the time of payment of the registration fee.◈ acquiring the volume of the object by the controller based on an output value of a sensor mounted on the X-ray source;
determining, by the controller, the degree of obesity of the subject based on the volume of the subject; and
adjusting, by the controller, an irradiation value of X-rays irradiated from the X-ray source based on the degree of obesity of the object;
including that,
The sensor includes a plurality of image sensors,
The output value of the sensor is
A method of controlling an X-ray imaging apparatus including inclined angles of the plurality of image sensors while the X-ray source moves. ◈Claim 24 was abandoned when paying the registration fee.◈ 24. The method of claim 23,
The control method of the X-ray imaging apparatus,
moving the imaging table up and down by the table actuator;
Further comprising; based on the output value of the table actuator according to the movement of the imaging table by the control unit, determining the weight of the object;
Adjusting the irradiation value of the X-rays,
A control method of an X-ray imaging apparatus of adjusting, by the controller, an irradiation value of X-rays irradiated from an X-ray source based on the weight of the object. ◈Claim 25 was abandoned when paying the registration fee.◈ 24. The method of claim 23,
The control method of the X-ray imaging apparatus,
acquiring the key of the object by the controller based on an output value of a sensor mounted on the X-ray source;
Further comprising; obtaining the weight of the object based on the output value of the table actuator for moving the imaging table by the control unit;
Adjusting the irradiation value of the X-rays,
The control method of the X-ray imaging apparatus of adjusting, by the controller, an irradiation value of X-rays irradiated from the X-ray source further based on the height and weight of the object.

Images