KR20160011138A - X-ray imaging apparatus and control method for the same - Google Patents

Abstract

The present invention relates to an X-ray imaging apparatus and a control method for the same. The X-ray imaging apparatus comprises: an X-ray source which irradiates an object with an X-ray; a sensor which is mounted on the X-ray source; and a control unit which obtains the volume of the object based on the output value of the sensor, determines the extent of obesity of the object based on the volume of the object, and adjusts an irradiation value of the X-ray based on the extent of obesity of the object. When the sensor includes a plurality of image sensors, the output value of the sensor includes an inclined angle of the image sensors while the X-ray source moves. According to the X-ray imaging apparatus and the control method for the same, it is possible to automatically detect characteristics of the object, such as the extent of obesity. Moreover, it is possible to automatically adjust the intensity of the X-ray based on the detected characteristics of the object, and thus, to improve the quality of an X-ray image.

Description

Technical Field [0001] The present invention relates to an X-ray imaging apparatus and a control method thereof,

Ray photographing apparatus for detecting a characteristic of a target object and a control method thereof.

An X-ray imaging apparatus is an apparatus for acquiring an image of an object using an X-ray. The X-ray imaging apparatus images the inside of the object by a non-invasive method of irradiating the object with the X-rays and detecting the X-rays transmitted through the object. Therefore, the medical X-ray imaging apparatus can be used for diagnosis of injury or illness in the inside of the object which can not be confirmed by appearance.

An X-ray imaging apparatus includes an X-ray source for generating an X-ray to irradiate a target object and an X-ray detector for detecting an X-ray transmitted through the target object. , And X-ray detectors.

For example, it is possible to automatically detect the position of an X-ray detector and perform auto tracking or auto centering, or to automatically detect the characteristics of a target object or to detect an X-ray source or an X-ray detector There is a demand for development of automation of an X-ray photographing apparatus such as automatically changing the position or automatically adjusting the intensity of the X-ray according to the characteristics of the detected object.

An X-ray photographing apparatus and its control method for automatically detecting a characteristic of a target object are provided.

An X-ray imaging apparatus according to one side includes an X-ray source for irradiating X-rays to a target object; A sensor mounted on the x-ray source; And a control unit for acquiring the volume of the object based on the output value of the sensor, determining the degree of obesity of the subject based on the volume of the subject, and adjusting the irradiation value of the X-ray based on the degree of obesity of the subject And the output value of the sensor may include the tilted angle of the plurality of image sensors while the x-ray source is moving, when the sensor includes a plurality of image sensors.

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

The output value of the sensor may include a pixel value of an image captured by the plurality of image sensors.

The control unit may detect an outline of the object on the image based on the change of the pixel value, and obtain the volume and the key of the object line based on the outline.

The apparatus may further include a source actuator for moving the X-ray source.

Further, the control unit may control the source actuator such that the x-ray source moves in the longitudinal direction of the photographing table when the sensor includes a proximity sensor or includes a plurality of image sensors.

In addition, the output value of the sensor may include an output voltage output from the proximity sensor while the x-ray source is moving.

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

The control unit obtains a first distance by converting the maximum output voltage among the output voltages, acquires a second distance by converting a minimum output voltage of the output voltages, and calculates a difference between the first distance and the second distance The volume of the object can be obtained from the object.

Also, the controller may obtain the key of the object from a difference between a movement distance of the x-ray source and a movement distance of the x-ray source, the interval in which the proximity sensor outputs a minimum output voltage.

In addition, the plurality of image sensors may have the same focal point.

Further, the control unit may calculate the distance from the plurality of image sensors using the following formula (3).

&Quot; (3) "

Here, d 'denotes a distance between the plurality of image sensors,? 1,? 2 denotes a tilted angle of the plurality of image sensors with respect to the focus, and d denotes a distance from the plurality of image sensors to the focal point.

In addition, the control unit may obtain the volume of the object from the difference between the maximum distance and the minimum distance among the calculated distances.

Also, the control unit may obtain the key of the object from the difference between the movement distance of the x-ray source and the movement distance of the x-ray source.

The irradiation value of the X-ray may correspond to the irradiation intensity or the irradiation amount of the X-ray.

An X-ray imaging apparatus according to one side includes an X-ray source for irradiating X-rays to a target object; A table actuator for moving the photographing table; And a controller for determining the weight of the object based on the output value of the table actuator and adjusting the irradiation value of the X-ray 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.

The output value of the table actuator may include a load current flowing on the table actuator while the photographing table moves in the vertical direction.

The control unit may extract a measurement current from a load current flowing on the table actuator in accordance with a sample rate, and calculate an average current from the extracted measurement current using Equation (2).

&Quot; (2) "

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

In addition, the control unit may determine the degree of obesity of the subject by comparing the load current with at least one current reference value set in advance.

The control unit may determine the weight of the target object based on the load current, and determine the degree of obesity of the target object by comparing the determined weight of the target object with at least one predetermined weight reference value.

An X-ray imaging apparatus according to one side includes an X-ray source for irradiating X-rays to a target object; A sensor mounted on the x-ray source; A table actuator for moving the photographing table; And a control unit for acquiring the key of the object based on the output value of the sensor, acquiring the weight of the object based on the output value of the table actuator, and adjusting the irradiation value of the X- . ≪ / RTI >

A control method of an X-ray photographing apparatus according to one side obtains a volume of a target 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 irradiance value of an X-ray irradiated from the X-ray source based on the degree of obesity of the object, wherein, when the sensor includes a plurality of image sensors, The angle of inclination of the plurality of image sensors may be included.

A control method of an X-ray photographing apparatus according to one side of the present invention includes: moving a photographing table in a vertical direction; Judging a weight of the object based on an output value of the table actuator according to the movement of the photographing table; And adjusting the irradiation value of the X-ray irradiated from the X-ray source based on the weight of the object.

A control method of an X-ray photographing apparatus according to one side obtains a key of an object based on an output value of a sensor mounted on an X-ray source; Acquiring a weight of the object based on an output value of the table actuator for moving the photographing table; And adjusting an irradiation value of an X-ray irradiated from the X-ray source based on the key and the weight of the object.

1 is a perspective view illustrating an appearance of an X-ray imaging apparatus.
2 is an exploded perspective view showing the X-ray imaging apparatus in a disassembled state.
3 is a perspective view illustrating an operation unit of the X-ray imaging apparatus.
4 is a control block diagram according to an embodiment of the X-ray imaging apparatus.
5 is a cross-sectional view illustrating the internal structure of the x-ray tube.
6 is a schematic view schematically showing the structure of the sensing panel.
Fig. 7 is a graph showing the relationship between the energy and the damping coefficient for each substance in the object.
8 is a view for explaining a damping phenomenon depending on the thickness of the fat.
9 is a configuration diagram according to an embodiment of the table actuator.
10 is a configuration diagram according to another embodiment of the table actuator.
11 is a configuration diagram according to another embodiment of the table actuator.
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 according to another embodiment of the X-ray imaging apparatus.
16 is a view for explaining distance sensing by the proximity sensor.
17 is a diagram for explaining a method of detecting a key and a volume of a target object by using an output value of the proximity sensor.
18 is a diagram for explaining image acquisition by a single image sensor.
19 is a diagram for explaining a method of detecting a key and a volume of a target object by using an output value of the image sensor.
20 is a view for explaining distance sensing by a plurality of image sensors.
21 is a view for explaining a method of detecting a key and a volume of a target object by using output values of a plurality of image sensors.
22 is a control block diagram according to another embodiment of the X-ray imaging apparatus.
23 is a flowchart according to an embodiment of a control method of an X-ray imaging apparatus.
24 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.
25 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.
26 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory only and are not restrictive of the invention, as claimed, and it is to be understood that the invention is not limited to the disclosed embodiments.

Hereinafter, an X-ray imaging apparatus and a control method thereof will be described in detail with reference to the embodiments described below with reference to the accompanying drawings. Like numbers refer to like elements throughout the drawings.

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

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

The guide rail 30, the movable carriage 40, the post frame 50, and the like 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 at predetermined angles with respect to each other. It is preferable that the first guide rail 31 and the second guide rail 32 extend in directions perpendicular to each other.

The first guide rails 31 are installed on the ceiling of the examination room where the radiographic apparatus is disposed. The second guide rail 32 is located on the lower side of the first guide rail 31 and is slidably mounted on the first guide rail 31. The first guide rail 31 may be provided with rollers (not shown) movable along the first guide rails 31. The second guide rail 32 is connected to the 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. Therefore, the first direction D1 and the second direction D2 may be orthogonal to each other and parallel to the ceiling of the examination room.

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

The length of the post frame 50 may be increased or decreased in the vertical direction while the post frame 50 is fixed to the carriage 40. The post frames 51, 52, 53, 54,

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

The X-ray source 70 is a device for irradiating X-rays to a target object.

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

The X-ray source 70 may include an X-ray tube 71 for generating an X-ray and a collimator 72 for guiding the generated X-ray toward a target object. Will be described later.

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

The rotational joint 60 couples the x-ray source 70 to the post frame 50 and supports the load exerted on the x-ray source 70. The rotary joint 60 may include a first rotary joint 61 connected to the lower end post 51 of the post frame 50 and a second rotary joint 62 connected to the X-

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

The second rotary joint 62 is rotatable on a plane perpendicular to the ceiling of the examination room. Therefore, the second rotary joint 62 can rotate in the rotating direction of the axis parallel to the first direction D1 or the second direction D2. At this time, the rotation direction of the second rotary joint 62 can be newly defined, and the newly defined fifth direction D5 is the rotation direction of the axis extending in the first direction or the second direction. The x-ray source 70 may be connected to the rotary joint 60 and rotated in the fourth direction D4 and the fifth direction D5. The X-ray source 70 may be connected to the post frame 50 by the rotary joint 60 and linearly move 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 driver for driving the motor and 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 their respective directions.

Each of the actuators 111, 112, 113, 114, and 115 may be disposed at 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 the moving carriage 40 is moved in the second direction The third actuator 113 for moving the second frame 112 to move the post frame 50 in the third direction D3 is disposed in the moving carriage 40). The fourth actuator 114 for rotating the X-ray source 70 in the fourth direction D4 is disposed around the first rotational joint 61 and the X-ray source 70 is rotated in the fifth direction D5 The fifth actuator 115 for rotationally moving can be disposed around the second rotary joint 62. [

Hereinafter, the first actuator 111, the second actuator 112, and the third actuator 113 that move the movable carriage 40 will be referred to as a carriage actuator 110 hereinafter.

Each of the actuators 111, 112, 113, 114 and 115 is connected to power transmission means (not shown) to linearly or rotationally move the x-ray source 70 in the first direction D1 to the fifth direction D5 . The power transmission means (not shown) may be a commonly used belt and pulley, chain and sprocket, shaft or the like.

One side of the X-ray source 70 is provided with an operation unit 80 for providing a user interface. Here, the user may be a medical staff including a doctor, a radiologist, a nurse, and the like as a person who performs diagnosis of a target object using the X-ray imaging apparatus 100, but the present invention is not limited thereto, It is assumed that all users can become users.

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

3, the operation unit 80 may include a button 83 and a display panel 81. The user may press the button 83 or touch the display panel 81, You can enter various information about X-ray photography or operate each device. The display panel 81 may be a cathode ray tube (CRT), a digital light processing (DLP) panel, a plasma display panel (LCD) panel, a liquid crystal display (EL) panel, an electrophoretic display (EPD) panel, an electrochromic display (ECD) panel, a light emitting diode (LED) panel or an organic light emitting diode OLED) panel, but the present invention is not limited thereto.

Further, the operation unit 80 includes a handle 82 so that the user can grasp it. That is, the user grasps the handle 82 of the operation unit 80 and applies force or torque to linearly move the X-ray source 70 in the first direction D1 to the third direction D3, (D4) and the fifth direction (D5). 3, the handle 82 is illustrated as being provided at the lower portion of the operation unit 80, but it may be provided at another position of the operation unit 80 as well.

The operation unit 80 may include a central processing unit (CPU), a graphic processing unit (GPU), and various types of storage devices implemented by a microprocessor or the like, And may be provided on a printed circuit board (PCB). The operation unit 80 includes a printed circuit board and is provided on one side of the X-ray source 70, and may be referred to as a " Tube Head Board "or" THU ".

Referring again to FIG. 1, the workstation 170 includes an input unit 171 and a display unit 172, and provides a user interface together with the operation unit 80. Accordingly, the user can input various information related to the X-ray imaging through the workstation 170 or operate the respective devices. For example, the user can set a photographing condition according to a photographed region through the work station 170, or input a move command of the movable carriage 40 or the x-ray source 70, or an x-ray start command . In addition, the user can confirm the images obtained in the X-ray photographing process through the workstation 170. [

The input unit 171 includes hardware input devices such as various buttons or switches, a keyboard, a mouse, a track-ball, various levers, a handle, a stick, . 1, the input unit 210 may be provided on the upper portion of the work station 170. However, when the input unit 210 is implemented as a foot switch, a foot pedal, or the like, Or may be provided at a lower portion of the station 170.

The input unit 171 may include a graphical user interface (GUI), such as a touch pad or the like, for inputting a user.

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

The display unit 172 includes a cathode ray tube (CRT), a digital light processing (DLP) panel, a plasma display panel (PDP), a liquid crystal display A liquid crystal display (LCD) panel, an electroluminescence (EL) panel, an electrophoretic display (EPD) panel, an electrochromic display (ECD) panel, a light emitting diode ) Panel or an organic light emitting diode (OLED) panel, but the present invention is not limited thereto.

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

The workstation 170 is also provided with various processing devices such as a central processing unit (CPU), a graphic processing unit (GPU), and the like, and a printed circuit board ; PCB) can be built in. Accordingly, the workstation 170 receives main components of the X-ray photographing apparatus 1, for example, a controller (500 of FIG. 4) to perform various judgments for the operation of the X-ray photographing apparatus 1, Signal can be generated.

The user can input information through the cut-off screen B without being exposed to the X-ray while the X-ray photographing is in progress, Can be operated.

The X-ray detector 90 is an apparatus for detecting X-rays transmitted through a target object.

The X-ray detector 90 can be mounted on the photographing table 10 or the photographing stand 20 during X-ray photographing. The photographing table 10 is provided with a table mounting portion 15 for mounting the X-ray detector 90 and the table mounting portion 15 is provided movably in the longitudinal direction of the photographing table 10. Similarly, the photographing stand 20 is provided with a stand mounting portion 25 for mounting the X-ray detector 90, and the stand mounting portion 25 is provided movably in the longitudinal direction of the photographing stand 20. At this time, the longitudinal direction of the photographing table 10 can be defined in the sixth direction D6, and the longitudinal direction of the photographing stand 20 can be defined in the seventh direction D7, respectively. The table mounting portion 15 or the stand mounting portion 25 on which the X-ray detector 90 is mounted moves along the sixth direction D6 or the seventh direction D7 so that the entire or specific portion of the object can be photographed.

The photographing table 10 includes a support table 12 for supporting the photographing table 10 and adjusting the height of the photographing table 10 and a table actuator 12 for moving the support table 12 in the vertical direction. (See 200 in Fig. 4) may be provided. At this time, the up and down direction of the support table 12 is defined as the eighth direction D8, and a detailed description of the table actuator will be described later.

Hereinafter, the configuration of the X-ray imaging apparatus 100 for detecting the characteristics of the object, particularly the degree of obesity, and the role of each configuration will be described in detail.

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

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

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

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

The X-ray tube 71 may be a bipolar tube including an anode 71c and a cathode 71e, and the tube may be a glass tube 71a made of a material such as a hard silica glass.

The cathode 71e includes a filament 71h and a focusing electrode 71g for focusing electrons and the focusing electrode 71g is also called a focusing cup. The inside of the glass tube 71a is made to a high vacuum state of about 10 mmHg and the filament 71h of the cathode is heated to a high temperature to generate thermoelectrons. As an example of the filament 71h, a tungsten filament can be used, and the filament 71h can be heated by applying an electric current to the electric wire 71f connected to the filament. However, the embodiment of the disclosed invention is not limited to the use of the filament 71h in the cathode 71e, and it is also possible to use a carbon nanotube which can be driven by a high-speed pulse, as the cathode.

The anode 71c is mainly made of copper and the target material 71d is coated or disposed on the side facing the cathode 71e and the target material is a high resistance material such as Cr, Fe, Co, Ni, 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, the thermoelectrons 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 can be used as the material of the window.

The target material 71d can be rotated by the rotor 71b and the heat accumulation ratio can be increased by 10 times or more per unit area as compared with the case where the target material 71d is rotated and the focus size is reduced .

The 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 can be expressed by the peak value kvp. As the tube voltage increases, the speed of the thermoelectrons increases and consequently the energy (photon energy) of the x-ray generated by collision with the target material increases. The current flowing through the X-ray tube 71 is referred to as a tube current and can be expressed as an average value mA. When the tube current increases, the dose of the X-ray (the number of photons) increases. That is, the energy of the x-ray can be controlled by the tube voltage, and the dose of the x-ray can be controlled by the tube current.

The X-ray detector 90 is an apparatus for detecting X-rays transmitted through an object irradiated from the X-ray source 70. Detection of such X-rays is performed in the detection panel 120 inside the X-ray detector 90. In addition, the sensing panel 120 converts the detected X-rays into electrical signals to acquire x-ray images inside the object.

The sensing panel 120 may be classified according to a material construction method, a method of converting detected x-rays into an electrical signal, and a method of acquiring an electrical signal.

First, the sensing panel 120 is divided into a case where the sensing panel 120 is composed of a single type device and a case where the sensing panel 120 is composed of a horn molding device.

In the case of a single-element device, it corresponds to a case where a part for detecting an X-ray to generate an electric signal and a part for reading and processing an electric signal are made of a single material semiconductor or manufactured by a single process. For example, (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor), which are devices.

In the case of a horn-forming device, a portion for detecting an X-ray to generate an electrical signal and a portion for reading and processing an electrical signal are made of different materials or are manufactured by different processes. For example, when an X-ray is detected using a light receiving element such as a photodiode, a CCD, or a CdZnTe, and an electrical signal is read and processed by using a CMOS ROIC (Read Out Integrated Circuit), a strip detector is used to detect the X- When reading and processing electrical signals using ROIC, and when using an a-Si or a-Se flat panel system.

The sensing panel 120 is divided into a direct conversion method and an indirect conversion method according to a method of converting an X-ray into an electrical signal.

In the direct conversion method, when the X-ray is irradiated, the electron-hole pairs are temporarily generated inside the light-receiving element, the electrons move to the anode and the holes move to the cathode due to the electric field applied to both ends of the light- This converts this movement into an electrical signal. The materials used for the light-receiving element in the direct conversion system include a-Se, CdZnTe, HgI2, and PbI2.

In the indirect conversion method, when an X-ray irradiated from the X-ray source 70 reacts with a scintillator to emit a photon having a wavelength in a visible light region, the light receiving element senses the converted photon and converts it into an electrical signal. In the indirect conversion method, a-Si is used as a light-receiving element. As the scintillator, a GADOX scintillation thin film, a micro-columnar or needle-structured CSI (T1) is used.

In addition, the sensing panel 120 may include a charge accumulation mode (Charge Integration Mode) for storing a charge for a predetermined period of time and acquiring a signal therefrom, and a charge accumulation mode (Photon counting mode).

The sensing panel 120 is applicable in any of the above-described ways. In addition, the sensing panel 120 may have a two-dimensional array structure including a plurality of pixels 150.

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

6, the sensing panel 120 may include a light receiving element 121 for detecting an X-ray and generating an electric signal, and a read-out circuit 122 for reading the generated electric signal.

As the light receiving element 121, a single crystal semiconductor material may be used to secure a high resolution, a fast response time, and a high dynamic range at a low energy and a small dose. The single crystal semiconductor material used in this case is Ge, CdTe, CdZnTe, GaAs .

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

The read circuit 122 using a CMOS (Complementary Metal Oxide Semiconductor) process forms a two-dimensional array structure and can be coupled to the p-type substrate 121c of the light receiving element 121 for each pixel 150. [ In this case, a flip-chip bonding method may be used in which a bump 123 such as solder PbSn or indium (In) is formed and then reflowed, heated and compressed.

The X-ray irradiated from the X-ray source 70 is transmitted through the object, and its intensity is attenuated by scattering, absorption or the like. Accordingly, the X-ray detector 90 detects the attenuated X-ray. The attenuation of the x-ray differs depending on the energy level of the material and the x-ray constituting the object, and the attenuation degree of the x-ray according to the energy level of the constituent material and the x- attenuation coefficient.

Fig. 7 is a graph showing the relationship between the energy and the damping coefficient for each substance in the object.

Referring to FIG. 7, the damping coefficient depends on the constituent material inside the object. The curve representing the damping coefficient of the bone is located above the curve representing the damping coefficient of the soft tissue (muscle, fat), and when the X1 ray of the same energy level, for example, E1 is irradiated, the damping coefficient of the bone is (B1) The damping coefficient M1 of the muscle is greater than the damping coefficient F1 of the fat. That is, different materials in the object have different damping coefficients, and the damping coefficient increases as the material properties become harder.

The damping factor depends on the energy level of the irradiated x-ray, and the difference in attenuation coefficient between the materials also depends on the energy level of the x-ray. In the graph of FIG. 4, when the X-rays of the energy levels E1 and E2 are irradiated to the object made of bone, the attenuation coefficient B1 at E1 having a low energy level is lower than the attenuation coefficient B2 at E2 having a high energy level Big. The damping coefficients M1 and F1 when the energy level E1 is irradiated are larger than the damping coefficients M2 and F2 when the energy level E2 is irradiated even when the constituent material of the object is muscle or fat Respectively. That is, the damping coefficient increases as the energy level of the X-rays irradiated on the object 35 becomes lower.

The attenuation phenomenon of the X-ray may vary depending on the thickness of the object or the thickness of each material constituting the object, as shown in Equation (1) below.

Where I0 is the intensity of the x-ray irradiated to the substance, I is the intensity of the x-ray transmitted through the substance, and (E) is the attenuation coefficient of the substance with respect to the x- T is the thickness of the material through which the x-rays are transmitted.

According to Equation (1), even if the damping coefficient is the same, the thicker the material, the greater the degree of attenuation of the X-ray. In other words, even if the X-ray is irradiated with the same intensity and energy level for the same material, the thicker the material, the smaller the intensity of the transmitted X-ray.

8 is a view for explaining a damping phenomenon depending on the thickness of the fat.

8 shows that a subject having a normal amount of fat is irradiated with X-rays, and the right side of FIG. 8 shows that X-rays are irradiated to a subject having a fat amount higher than normal (that is, obese). As described above, as the thickness of the substance becomes thicker, the degree of attenuation of the X-ray increases, and even when the constituent material of the subject, for example, fat is compared, the more the amount of fat or fat (i.e., the higher the degree of obesity) The intensity of the light is reduced.

The degree of obesity described below refers to the amount, thickness, or ratio of the substances constituting the target site to be photographed by irradiating the X-ray. As described above, the irradiation value of the x-ray must be adjusted according to the ratio of fat, bone, and muscle constituting the target site to be photographed by irradiating the x-ray, Can be improved. Accordingly, the X-ray photographing apparatus 102 according to the disclosed embodiment can determine the degree of obesity and adjust the irradiation value of the X-ray according to the determination result. 8, when the X-ray source 70 irradiates the X-rays at the same intensity and energy level, the right-side object (i.e., the object having the normal amount of fat) Scattering or absorption of the X-ray occurs to a large extent (that is, an obese subject), and thus the X-ray detector 90 for detecting the transmitted X-ray detects the X-ray of a smaller intensity on the right side. In other words, the greater the degree of obesity of the target object, the smaller the intensity of the X-ray detected by the X-ray detector, and consequently the quality of the X-ray image acquired through the X-ray imaging apparatus 100 may be degraded. The control unit 500 controls the X-ray source 70 to increase the intensity of the X-ray as the degree of obesity of the subject increases, and the table actuator 200 may operate to determine the degree of obesity of the subject.

The table actuator 200 drives the table motor (refer to 213 in Fig. 9, 223 in Fig. 10 and 233 in Fig. 10) in accordance with the control signal of the control section 500 and drives the photographing table 10 in the eighth direction D8 ). The table actuator 200 measures the current flowing through the table actuator 200 while the photographing table 10 is moving 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 presence or absence of the target object and the weight of the target object (i.e., the load applied to the table actuator 200).

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

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

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

On the other hand, the voltage difference across the resistor (R, 211) or the current Im flowing through the resistor (R, 211) may be measured using an external measuring instrument. According to one embodiment, the external measuring device includes a device capable of measuring voltage, current, etc., such as a multimeter, but it is not limited to one embodiment, .

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

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

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

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

The configuration of the table actuator 200 described above with reference to FIGS. 9, 10 and 11 is merely an example. If the current flowing through the table actuator 200 can be measured at the time of driving the table motor, 200 may have different configurations, but are not limited thereto.

The table actuator 200 moves the photographing table 10 in the eighth direction D8 in the state where the object exists (i.e., when the object is loaded) and measures the electric current. In this way, the current measured at the time of the presence of the target object (i.e., at the time of the load) can be referred to as the current at the time of the load, and in the state where the target object does not exist corresponding to the current at the time of the load 10), the measured current can be defined as no-load current.

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

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

The controller 500 may generate a control signal for current measurement and transmit the control signal to the table actuator 200. The control unit 500 receives the current measured by the table actuator 200 and can determine the degree of obesity of the target object using the received current.

The control unit 500 may calculate the current received from the table actuator 200 as an average current and determine the degree of obesity of the target object using the average current.

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

The motor drivers 212, 222 and 223 receive power and drive the table motors 213, 223 and 233. At this time, the analog current flowing on the table actuator 200 is shown in And may have a graph form as illustrated. At the beginning of the table motors 213, 223, and 233, an inrush current can be detected.

In order to reduce the error due to the starting current, the controller 500 may determine the degree of obesity using the current measured after the predetermined time, but the controller 500 may determine the degree of obesity as shown in FIG. 12B or FIG. Similarly, the measured current may be used for a predetermined time period T. [

Specifically, the analog current shown in FIG. 12A is converted into a digital current through the ADC of the table actuator 200 as shown in FIG. 12B, and then transmitted to the controller 500 . That is, the ADC can transmit the measurement current extracted according to a predetermined sample rate to the control unit 500.

The control unit 500 can calculate the average current of the measurement current extracted during the predetermined time period T based on the time T0 at which the table motors 213, 223, and 233 start to be driven, The following equation (2) can be used.

Here, Xi (i = 1, 2, ..., n) denotes an extracted measured current, n denotes the number of extracted times, and Xrms denotes an 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. T1, T2, T3, and T4 are taken as the extraction time points of the measurement current according to the sample rate during a predetermined time region T, When the corresponding measured currents are X1, X2, X3, and X4, the controller 500 calculates an average current Xrms using Equation (2)

When the control unit 500 calculates the average current, the above-mentioned load current at the time of the load indicates the average current with respect to the measured current at the time of load, and the current at no load indicates the average Respectively.

On the other hand, the method by which the controller 500 calculates the average current is not limited to the above-described method. For example, when the extracted measured currents are arranged in order of magnitude, the control unit 500 can calculate the median value located in the middle of the measured currents as an average current, and calculate the most extracted mode as the average current Alternatively, if at least one of the extracted measurement currents is larger or smaller than a predetermined level in comparison with other measurement currents, the control unit 500 determines this as an error and excludes it when calculating the average current As another example, in calculating the average current, the measurement current value having the minimum value and the measurement current value having the maximum value among the extracted measurement currents may be determined as an error, and the average current may be calculated excluding the measurement current value. In addition, the controller 500 can calculate an average current through various average calculation methods, and is not limited to the above-described method.

The control unit 500 determines the degree of obesity of the subject using the measured or calculated load current. The control unit 500 may compare the current at the time of the load with a preset current reference value to determine the degree of obesity of the subject, compare the weight of the subject calculated from the current at the time of the load with a predetermined weight reference value, You can judge. At this time, the current reference value means a current value corresponding to the reference weight that can determine the degree of obesity, and at least one current reference value may be preset and stored in the storage unit 550. [ Likewise, 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 (for example, 130 kg) that can be determined, and is set to be larger than the current at no load. Accordingly, the controller 500 compares the current at the time of the load with the current reference value P, and determines that the object is obese when the current at the time of the load becomes equal to or higher than the current reference value P. 13, since the load current has a value higher than the current reference value P, the controller 500 determines that the subject 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 (for example, 130 kg, 140 kg, and 150 kg), and are set to be larger than the no-load current, and the controller 500 sets a plurality of current reference values The degree of obesity of the subject can be determined.

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

The left graph in Fig. 14 shows the no-load current and the load current when measured in accordance with the weight of the object when the photographing table 10 moves in the opposite direction to the gravity direction, i.e., And the right graph of Fig. 14 shows the no-load current and the load current when measured according to the weight of the object when the photographing table 10 moves in the gravity direction, that is, the down direction . Here, the current when the weight is zero is the current when there is no load, and the current when the weight is zero is the load current.

The gravity causes the table actuator 200 to be subjected to a greater load when the photographing table 10 moves in the up direction than when the photographing table 10 moves in the down direction and the consumption of electric current also increases. Accordingly, when no load is applied, the current is 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.

Therefore, even when the reference weight W is the same, the current reference value P1 when the photographing table 10 moves in the up direction and the current reference value P2 when moving in the down direction can be set to be different from each other. That is, the current reference value P1 when moving in the up direction can be set higher than the current reference value P2 when moving in the down direction.

On the other hand, a motor for moving in the horizontal direction can be mounted on the photographing table 10. Accordingly, the photographing 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 amount of the electric current. At this time, the current reference value P3 when the photographing table 10 moves in the horizontal direction can be set differently from the current reference value P1 when moving upward and the current reference value P2 when moving downward.

In addition, the control unit 500 may determine the degree of obesity of the subject by comparing the weight of the subject calculated from the current at the time of the load with a predetermined weight reference value. To this end, the storage unit 550 may store at least one weight reference value and the graph of FIG. 14, that is, the relationship between the weight and the current, in the form of data.

Specifically, the control unit 500 calculates the current at the time of load using the relationship between the weight and the current, compares the calculated weight with a single weight reference value (for example, 130 kg), and determines the degree of obesity Or by comparing the calculated weight with a plurality of weight reference values (for example, 130 kg, 140 kg, and 150 kg) that gradually increase the calculated weight, the degree of obesity of the subject can be determined.

On the other hand, an acceleration sensor can be mounted on the photographing table 10 or the X-ray detector 90. When the photographing table 10 moves in the horizontal direction, the upward direction, or the downward direction, the instantaneous acceleration of the photographing table 10 differs depending on the weight of the object. Further, even if the photographing table 10 moves in the same direction and the motor operates with the same power, the larger the weight of the object is, the smaller the instantaneous acceleration is. That is, the weight of the object and the instantaneous acceleration of the photographing table 10 correspond to an inverse proportion relation. Accordingly, the control unit 500 may measure the instantaneous acceleration of the photographing table 10 through the acceleration sensor, and determine the degree of obesity of the object based on the instantaneous acceleration. The 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 can calculate the weight corresponding to the measured instantaneous acceleration using the data stored in the storage unit 550. [

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

The control unit 500 controls the X-ray source 70 to irradiate an X-ray of a larger intensity to an obese subject than a subject having a normal amount of fat. The control unit 500 controls the X-ray source 70 to irradiate X-rays having a larger intensity as the degree of obesity of the subject increases. At this time, the irradiation intensity of the X-rays for each of the object having the normal lipid amount and the object of the obese subject may be preset and stored for each imaging site and likewise, the irradiation value of the X- And may be stored.

The control unit 500 receives the x-ray detected 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-ray.

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

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

For example, the storage unit 550 may store at least one predetermined current reference value for comparison between the current and the current reference value at the time of the load. Alternatively, the storage unit 550 stores a graph of the relationship between the weight and the current when the photographing table 10 moves in the up direction, The relationship graph between the weight and the current when the photographing table 10 is moved in the down direction can be stored in the form of data. The storage unit 550 may store the irradiation intensity of the X-rays for each of the object having the at least one predetermined weight reference value and the normal amount of fat and the obese subject and the storage unit 550 according to the imaging region, Strength can also be saved. 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. a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (for example, SD or XD memory), a random access memory (RAM) At least one of a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM) Of the storage medium. 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. Meanwhile, the storage unit 550 stores the degree of obesity predicted through the program, The actual degree of obesity of the subject can be stored. Accordingly, the control unit 500 can update the program by comparing the result predicted through the program with the actual state of the object and performing a process of correcting the error. The control unit 500 according to the disclosed embodiment can more accurately determine the degree of obesity of the subject by continuously updating the program.

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

15, an 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, 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 components as those described above will be omitted.

The sensor 300 may be mounted to the x-ray source 70 to sense the distance from the x-ray source 70 to the object or 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 with a proximity sensor (see S1 in FIG. 16) to sense the distance between the x-ray source 70 and the object. At this time, the proximity sensor S1 may be provided in the form of an ultrasonic sensor, an optical sensor (for example, an infrared sensor, a PSD sensor, a CCD sensor, or the like), or an RF sensor.

For example, the x-ray photographing apparatus 102 can adjust the angle of the proximity sensor SI to sense the distance between the x-ray source 70 and the object. As another example, when the proximity sensor SI is mounted on the x-ray source 70, the x-ray photographing apparatus 102 detects the distance between the x-ray source 70 and the object in accordance with the movement of the x- .

16 is a view for explaining distance sensing by the proximity sensor.

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 photographing table 10 in accordance with the control signal of the control unit 500 and the proximity sensor S1 detects the X-ray source 70 while moving the photographing table 10 or the object ob). The output value of the proximity sensor S1 along the distance is transmitted to the control unit 500. The control unit 500 detects the key and the volume of the target object and determines the degree of obesity of the target object.

17 is a diagram for explaining a method of detecting a key and a volume of a target object by using an output value of the proximity sensor.

The upper graph of Fig. 17 shows the output voltage of the proximity sensor S1 along the distance. When the object is present within the predetermined distance Pd from the proximity sensor S1, the output voltage of the proximity sensor S1 increases sharply 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 becomes longer. That is, the output voltage of the proximity sensor S1 rapidly increases in proportion to the distance to the object within a certain distance Pd, but decreases inversely 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 target object ob is longer than the predetermined distance Pd, and the graph after the predetermined distance Pd, that is, it is possible to detect the key and the volume of ob.

The proximity sensor S1 transmits the output voltage that is output while the x-ray source 70 is moving to the control unit 500, and the shape of the output voltage may be as illustrated in the lower graph of Fig. As described above, since the output voltage of the proximity sensor S1 is inversely proportional to the distance, it is largest in the vicinity of the abdomen of the observer OB and remains the smallest value in the vicinity of the photographing table 10.

17, the control unit 500 converts the largest output voltage into a distance to the target object, converts the smallest output voltage to the distance to the photographing table 10, (ob). At this time, the obtained abdomen thickness can be the volume (V) of the object. In addition, the control unit 500 acquires the key H of the object ob in the lower graph of Fig. 17, excluding the both end portions that hold the smallest output voltage.

The control unit 500 determines the degree of obesity of the target ob by using the obtained volume V and the key H. As a method of determining the degree of obesity according to the volume (V) and the key (H), a known technique can be used, 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. When the carriage actuator 110 is driven, the X- And moves in the longitudinal direction of the photographing table 10. The carriage actuator 110 is for moving the x-ray source 70, and may be referred to as a source actuator 110 hereinafter. 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. 17, and stores a program for acquiring the volume V and the key H using the data .

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

18 is a diagram for explaining image acquisition by a single image sensor. 18, the image sensor S2 can be mounted singly near the lower end of the x-ray source 70, for example, around the collimator 72, to obtain an image at the top of the object. That is, the upper image of the object is obtained. The output value of the image sensor S2 is transmitted to the control unit 500. The control unit 500 detects the key and the volume of the target object and determines the degree of obesity of the target object.

19 is a view for explaining a method of detecting a key and a volume of a target object by using an output value of the image sensor.

The image sensor S1 can obtain the upper image of the object as illustrated in Fig. The output value of the image sensor S1 is the pixel value Px of the image and the pixel value Px of the image is the boundary between the portion where the object exists and the portion where the object does not exist, Change. Accordingly, the control unit 500 detects the outline Po of the object from the change of the pixel value Px, and calculates the abdominal width V of the object ob and the key H of the object based on the detected outline Po ). At this time, the obtained abdominal width V can be the volume of the object. The control unit 500 determines the degree of obesity of the target ob by using the obtained volume V and the key H.

When the sensor 300 is provided as a single image sensor S2, the storage unit 550 stores the pixel value Px of the image obtained by the image sensor S2 or the image output from the image sensor S2 as data 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 view for explaining distance sensing by a plurality of image sensors.

Referring to FIG. 20, a plurality of image sensors S21 and S22 may be mounted near the lower end of the X-ray source 70, for example, near the collimator 72. FIG. The plurality of image sensors S21 and S22 can be angularly adjusted to have the same focus (e.g., focus F). The X-ray source 70 moves in the longitudinal direction of the photographing table 10 in accordance with the control signal of the control unit 500 and the plurality of sensors S21 and S22 are moved to the photographing table 10 in accordance with the movement of the X- Or moves the focus F on the surface of the object ob. The output values of the image sensors S21 and S22 are transmitted to the control unit 500 while the focus F is moved and the control unit 500 calculates the distance to the photographing table 10 or the object ob using the result. At this time, the output value of the image sensors S21 and S22 may be an angle with respect to the focal point F. [ Further, the control unit 500 detects the key and the volume of the object from the calculated distance, and determines the degree of obesity of the object.

21 is a view for explaining a method of detecting a key and a volume of a target object by using output values of a plurality of image sensors.

The distance between the two image sensors S21 and S22 is d 'and the output values (i.e., angles) of the image sensors S21 and S22 with respect to the focal point F are θ1 and θ2 , The distance d from the image sensors S21 and S22 to the object can be expressed by the following equation (3).

The control unit 500 can calculate the distance d from the image sensors S21 and S22 to the photographing table 10 or the object ob using the output values of the image sensors S21 and S22 and the expression have.

As described above, the plurality of image sensors S21 and S22 move the focus F while the X-ray source 70 is moving and transmit the output value to the controller 500. [ The control unit 500 calculates the distance d from the image sensor S21. S22 to the photographing table 10 or the object ob corresponding to the movement position of the focal point F. The shape of the calculated distance d is the lower side 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 the largest value is maintained in the vicinity of the photographing table 10.

Accordingly, the controller 500 acquires 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. At this time, the obtained abdominal thickness can be the volume (V) of the object. In addition, the control unit 500 acquires the key H of the object ob, excluding the both end portions that hold the largest value in the lower graph of Fig. The control unit 500 determines the degree of obesity of the target ob by using the obtained volume V and the key 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 The X-ray source 70 is moved in the longitudinal direction of the photographing table 10. The storage unit 550 may store the distance d 'between the image sensors S21 and S22 and may store the distance d' from the image sensors S21 and S22 based on the output values of the image sensors S21 and S22. d, a program for obtaining the volume V and the key H using the calculated distance d, and the like.

16 through 21, the sensor 300 includes only the proximity sensor or includes only the image sensor. However, the present invention is not limited thereto, and it is also possible that the proximity sensor and the image sensor are used in combination .

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

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, A storage unit 550, an input unit 171, and a display unit 172. In the following description of the components of the X-ray imaging apparatus 103 according to another embodiment, the same components as those of the X-ray imaging apparatus of FIG. 4 or 16 will be omitted.

The sensor 300 is mounted to 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 the proximity sensor, the image sensor alone, or the proximity sensor and the image sensor. Further, when the sensor 300 includes an image sensor, the image sensor may be provided in at least one.

When the sensor 300 includes a proximity sensor or a plurality of image sensors, the control unit 300 controls driving of the carriage actuator 110. When the carriage actuator 110 is driven, the X-ray source 70 moves (That is, while the X-ray source 70 moves in the longitudinal direction of the photographing 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 control unit 300 drives the carriage actuator 110 so that the x-ray source 70 is positioned on the object, and receives the output value of the single image sensor.

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

When the control unit 500 receives the output voltage of the proximity sensor, the maximum output voltage is converted into the distance to the target object according to the upper graph of Fig. 17, and the smallest output voltage is converted into the distance to the photographing table 10 , And obtains the difference between the converted values as the abdominal wall thickness (or volume V) of the object ob. In addition, the control unit 500 acquires the key H of the object ob in the lower graph of Fig. 17, excluding the both end portions that hold the smallest output voltage.

When the control unit 500 receives the pixel value Px of the image from the image sensor, the control unit 500 detects the outline Po of the object from the change of the pixel value Px, (V) and key (H).

When the control unit 500 receives the angle of the image sensor, the distance to the photographing table 10 or the object ob is calculated using Equation (3), and the distance between the largest value and the smallest value (Or volume V) of the object ob. In addition, the control unit 500 acquires the key H of the object ob, excluding the both end portions that hold the largest value in the lower graph of Fig.

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 in accordance with the control signal of the control unit 500 Measure current at load. The control unit 500 receives the current at the time of the load and calculates the current at the time of the load as the weight W of the target object by using the graph of the relationship between the weight and the current shown in Fig.

As another example, the control unit 500 may use various methods such as detecting the voltage or the current in parallel with the weight W of the object using the piezoelectric sensor and calculating the weight W of the object using the detection result The weight W of the object can be calculated.

The control unit 500 determines the degree of obesity of the subject by using the volume V, the height H, and the weight W of the acquired subject. A known technique can be used for determining the degree of obesity according to the volume (V), the height (H), and the weight (W), and a detailed description thereof will be omitted.

The control unit 500 can control the irradiated value of the X-ray irradiated from the X-ray source 70 by adjusting the tube voltage or the tube current of the X-ray tube 71 based on the judgment of the degree of obesity.

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

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

Referring to FIG. 23, the table actuator 200 drives the table motor in accordance with the control signal, and measures the load current flowing through the table actuator 200 when the table motor is driven (Step 711).

The table motor is driven in accordance with the control signal of the control unit 500 while the object is present in the photographing table 10 and the photographing table 10 is moved in the eighth direction D8, ) Direction or in the down direction. The table actuator 200 includes a current sensor, a magnetic sensor, or a current sensing circuit and measures the current flowing through the table actuator 200 during the movement of the photographing table 10 The load current is transferred to the control unit 500.

The control unit 500 compares the current at the time of load with at least one current reference value set in advance, and determines the degree of obesity of the target object (712).

The control unit 500 may convert the transmitted load current into an average current form. When a single current reference value is set, the control unit 500 can compare the current at the time of the load with a single current reference value to determine the degree of obesity of the object. If a plurality of current reference values are set, 500) can compare the current at the time of the load with a plurality of current reference values to determine the degree of obesity of the subject.

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

If it is determined that the subject is obese, the control unit 500 controls the X-ray to be irradiated with a larger intensity than a subject having a normal amount of fat. In addition, the control unit 500 controls the irradiation of the X-rays of greater intensity as the degree of obesity of the subject is higher. At this time, the irradiation intensity of the X-rays for each of the object having the normal lipid amount and the object of the obese subject may be preset and stored for each imaging site, and similarly, the intensity of the X- And may be stored.

24 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.

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

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

The control unit 500 may convert the transmitted load current into an average current form. Further, the control unit 500 calculates the load current at the load (W) using the graph of the relationship between the weight and the current shown in Fig. The control unit 500 calculates the weight W of the object using the graph on the left side of Fig. 14 and calculates the weight W of the object in step 721. In step 721, The controller 500 calculates the weight W of the object using the graph on the right side of Fig.

The control unit 500 compares the calculated weight of the target object with at least one predetermined weight reference value to determine the degree of obesity of the target object (723).

When a single weight reference value (for example, 130 kg) is set, the control unit 500 can determine the degree of obesity of the subject by comparing the calculated weight with a single weight reference value, The control unit 500 may compare the calculated weight with a plurality of weight reference values which are gradually increased to determine the degree of obesity of the subject.

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

25 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.

Referring to FIG. 25, first, the control unit 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 includes a plurality of image sensors, the control unit 500 determines whether the moving carriage 40 and the X- In the longitudinal direction of the carriage actuator 110. As shown in Fig. While the x-ray source 70 is moving, 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 control unit 500.

When the sensor 300 includes a single image sensor, the control unit 500 controls the carriage actuator 110 such that the moving carriage 40 and the x-ray source 70 connected thereto are positioned on the object, The pixel value Px of the image is transmitted to the controller 500. [

The control unit 500 detects the volume and the key of the object from the output value of the sensor 300 (732).

When the control unit 500 receives the output voltage of the proximity sensor, the maximum output voltage and the smallest output voltage are converted into the distance to the object ob and the distance from the photographing table 10, respectively, And obtains the difference between the converted values as the abdominal thickness (or volume V) of the object ob. In addition, the control unit 500 acquires the key H of the object ob in the lower graph of Fig. 17, excluding the both end portions that hold the smallest output voltage.

When the control unit 500 receives the pixel value Px of the image from the image sensor, the control unit 500 detects the outline Po of the object from the change of the pixel value Px, (V) and the key (H) of the target object of the target object.

When the control unit 500 receives the angle of the image sensor, the distance to the photographing table 10 or the object ob is calculated using Equation (3), and the distance between the largest value and the smallest value (Or volume V) of the object ob. In addition, the control unit 500 acquires the key H of the object ob, excluding the both end portions that hold the largest value in the lower graph of Fig.

The control unit 500 determines the degree of obesity of the subject using the volume and the key of the subject (733). Further, the control unit 500 adjusts the irradiation intensity of the X-ray to be irradiated by the X-ray source 70 based on the determination of the degree of obesity (734).

26 is a flowchart according to another embodiment of the control method of the X-ray imaging apparatus.

Referring to FIG. 26, the table actuator 200 drives the table motor according to the control signal, and measures the current during the load applied to the table actuator 200 when the table motor is driven (Step 741). Further, the control unit 500 calculates the weight of the object from the current at the time of the load (742). Steps 741 and 742 correspond to steps 721 and 722, respectively.

The control unit 500 controls the carriage actuator 110 to adjust the position of the X-ray source (743). Further, the control unit 500 detects the volume and the key of the object from the output value of the sensor 300 (744). Steps 743 and 744 correspond to steps 731 and 732, respectively, and steps 743 and 744 may precede step 741. [

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

Although the embodiments of the X-ray photographing apparatus and the X-ray photographing apparatus control method have been described with reference to the drawings exemplified above, those skilled in the art will appreciate that the present invention is not limited to the technical idea, It will be understood that the invention may be embodied in other specific forms without departing from the spirit or scope of the invention. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

100, 101, 102, 103: X-ray photographing apparatus
70: X-ray source 90: X-ray detector
110: carriage actuator 200: table actuator
300: sensor 500:
550:

Claims (25)

An x-ray source for irradiating an object with x-rays;
A sensor mounted on the x-ray source; And
A controller for acquiring a volume of the object based on the output value of the sensor, determining an obesity degree of the object based on the volume of the object, and adjusting an irradiation value of the X-ray based on the degree of obesity of the object;
Lt; / RTI >
The output value of the sensor
Wherein when the sensor comprises a plurality of image sensors, the x-ray source includes a tilted angle of the plurality of image sensors during movement. The method according to claim 1,
The sensor includes:
An x-ray photographing apparatus further comprising a proximity sensor. The method according to claim 1,
The output value of the sensor
And a pixel value of an image taken by said plurality of image sensors. The method of claim 3,
Wherein,
Detecting an outline of the object in the image based on a change in the pixel value, and acquiring a volume and a key of the object line based on the outline. The method according to claim 1,
A source actuator for moving the x-ray source;
Further comprising an X-ray photographing apparatus. 6. The method of claim 5,
Wherein,
Wherein the source actuator is controlled so that the x-ray source moves in the longitudinal direction of the photographing table when the sensor includes a proximity sensor or includes a plurality of image sensors. The method according to claim 6,
The output value of the sensor
And an output voltage output from the proximity sensor while the x-ray source is moving. 8. The method of claim 7,
Wherein,
Converts the output voltage into a distance from the proximity sensor, and acquires the volume of the object based on the converted distance. 9. The method of claim 8,
Wherein,
Obtaining a first distance by converting a maximum output voltage among the output voltages, converting a minimum output voltage among the output voltages to obtain a second distance, and calculating a volume of the object from a difference between the first distance and the second distance X-ray imaging device to acquire. 8. The method of claim 7,
Wherein,
And acquires a key of the object from a difference between a movement distance of the x-ray source and a movement distance of the x-ray source, the interval being the minimum output voltage output of the proximity sensor. The method according to claim 1,
Wherein the plurality of image sensors comprise:
X-ray photographing apparatus having the same focal point. The method according to claim 1,
Wherein,
Ray imaging apparatus for calculating the distance from the plurality of image sensors using the following equation (3).
&Quot; (3) "

Here, d 'denotes a distance between the plurality of image sensors,? 1,? 2 denotes a tilted angle of the plurality of image sensors with respect to the focus, and d denotes a distance from the plurality of image sensors to the focal point. 13. The method of claim 12,
Wherein,
And acquires the volume of the object from the difference between the maximum distance and the minimum distance among the calculated distances. 13. The method of claim 12,
Wherein,
And acquiring a key of the object from a difference between a movement distance of the x-ray source and a movement distance of the x-ray source. The method according to claim 1,
The irradiation value of the X-
And an X-ray photographing apparatus corresponding to the irradiation intensity or the irradiation amount of the X-ray. An x-ray source for irradiating an object with x-rays;
A table actuator for moving the photographing table; And
A controller for determining the weight of the object based on an output value of the table actuator and adjusting an irradiation value of the X-ray based on the weight of the object;
Ray photographing apparatus. 17. The method of claim 16,
The table actuator includes:
A current sensor, a magnetic sensor, and a current sensing circuit. 18. The method of claim 17,
Wherein the output value of the table actuator
And a load current flowing on the table actuator while the photographing table moves in the vertical direction. 19. The method of claim 18,
Wherein,
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).
&Quot; (2) "

Where Xi (i = 1, 2, ..., n) is the extracted measured current, n is the number of times extracted, and Xrms is the average current. 19. The method of claim 18,
Wherein,
And compares the load current with at least one preset current reference value to determine the degree of obesity of the subject. 19. The method of claim 18,
Wherein,
And determines the degree of obesity of the subject by determining the weight of the subject based on the load current, and comparing the weight of the determined subject with at least one predetermined weight reference value. An x-ray source for irradiating an object with x-rays;
A sensor mounted on the x-ray source;
A table actuator for moving the photographing table; And
A control unit for acquiring a key of the object based on an output value of the sensor, acquiring a weight of the object based on an output value of the table actuator, and adjusting an irradiation value of the X-ray based on a key and a weight of the object;
Ray photographing apparatus. Acquiring a volume of the object based on an output value of a sensor mounted on the X-ray source;
Determining the degree of obesity of the subject based on the volume of the subject; And
Adjusting an irradiation value of an X-ray irradiated from the X-ray source based on the degree of obesity of the subject;
≪ / RTI >
The output value of the sensor
Wherein when the sensor comprises a plurality of image sensors, the angle of inclination of the plurality of image sensors during the movement of the x-ray source is controlled. The photographing table is moved in the vertical direction;
Judging a 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 an X-ray irradiated from an X-ray source based on the weight of the object;
Ray imaging apparatus. Acquiring a key of an object based on an output value of a sensor mounted on an X-ray source;
Acquiring a weight of the object based on an output value of the table actuator for moving the photographing table;
Adjusting an irradiation value of an X-ray irradiated from the X-ray source based on a key and a weight of the object;
Ray imaging apparatus.

Images