Patent Number: 
Section: claims

1. An X-ray imaging apparatus comprising:a collimator including a plurality of blades to form a collimation area, wherein at least one blade of the plurality of blades is rotatable in a clockwise direction or in a counterclockwise direction;a display configured to display a guide image;an input device configured to receive n (n being an integer equal to or greater than three) number of input points with respect to the displayed guide image; andat least one processor configured to:set a polygon defined by the input points to a window area, and control the collimator to form a collimation area having a shape of the polygon defined by the input points, the collimator controlled to perform at least one movement of a rotational movement and a linear movement of at least one of the plurality of blades to place intersection points of the plurality of blades at locations of the input points, respectively, andcontrol the collimator to form a collimation area of a shape most similar to the polygon defined by the input points, in response to determining that the intersection points of the plurality of blades cannot be placed at the locations of the input points, respectively, by any of the at least one movement of the rotational movement and the linear movement of the at least one of the plurality of blades. 2. The X-ray imaging apparatus according to claim 1, wherein the at least one processor is configured to determine validity of the input points. 3. The X-ray imaging apparatus according to claim 2, wherein, in response to receiving an input point, the at least one processor is configured to determine validity of the input point, and if the at least one processor determines that the input point is invalid, the at least one processor is configured to display a result of that the input point is invalid through the display. 4. The X-ray imaging apparatus according to claim 2, wherein when a distance between a first input point and a second input point among the input points is less than a reference value, the at least one processor is configured to determine that an input point that is last input among the first input point and the second input point is invalid. 5. The X-ray imaging apparatus according to claim 2, wherein when at least three input points of the input points are located on a straight line, the at least one processor is configured to determine that an input point that is last input among the at least three input points is invalid. 6. The X-ray imaging apparatus according to claim 2, wherein when a figure defined by the input points has a concave shape, the at least one processor is configured to determine that an input point that is last input among the input points is invalid. 7. The X-ray imaging apparatus according to claim 6, wherein the at least one processor is configured to determine whether the figure defined by the input points has the concave shape based on whether an order in which a lastly input point among the input points is connected with previously input points is in a clockwise order or a counterclockwise order. 8. The X-ray imaging apparatus according to claim 2, wherein when the at least one processor determines that an input point among the input points is invalid, the input device is configured to receive a new input point that replaces the input point that is determined to be invalid. 9. The X-ray imaging apparatus according to claim 2, wherein when the at least one processor determines that all of the input points are valid, the at least one processor is configured to connect the input points to define the window area in a shape of the polygon. 10. The X-ray imaging apparatus according to claim 1, wherein the guide image includes at least one image among an X-ray image acquired by irradiating a low dose of X-rays on an object before main scanning, a camera image acquired by photographing the object with a camera, and a previously acquired X-ray image of the object. 11. The X-ray imaging apparatus according to claim 10, wherein when the at least one processor is configured to acquire an X-ray image corresponding to the collimation area of the shape most similar to the polygon defined by the input points, and to perform image processing on the acquired X-ray image. 12. The X-ray imaging apparatus according to claim 11, wherein the at least one processor is configured to perform the image processing in such a way to reduce brightness or definition of a remaining area except for the window area in the acquired X-ray image or to cut off the remaining area. 13. An X-ray imaging apparatus comprising:a collimator including a plurality of blades to form a collimation area, wherein at least one blade of the plurality of blades is rotatable in a clockwise direction or in a counterclockwise direction;a display configured to display a guide image;an input device configured to receive n number of a point for the guide image, the n number of the point input by a user, wherein n is an integer that is equal to or greater than 1; andat least one processor configured to set a circle defined by the n number of the point to a window area, to control the collimator to form a collimation area in a shape of a polygon including to the window area, and to perform image processing on an X-ray image acquired by X-rays passed through the collimation area to acquire an X-ray image corresponding to the window area,wherein, in response to determining that the collimator cannot form a collimation area having a shape of the circle defined by the n number of the point, the at least one processor is configured to control the collimator to form the collimation area in a shape of a square of which one side has a length equal to a diameter of the circle defined by the n number of the point. 14. The X-ray imaging apparatus according to claim 13, wherein when two points are input through the input device, the at least one processor is configured to set a circle whose diameter or radius is a straight line connecting the two points, to the window area. 15. The X-ray imaging apparatus according to claim 13, wherein when a point and a straight line starting from the point are input through the input device, the at least one processor is configured to set a circle whose center point is the point and whose radius is the straight line, to the window area. 16. The X-ray imaging apparatus according to claim 13, wherein when a point and a straight line starting from the point are input through the input device, the at least one processor is configured to set a circle whose diameter is the straight line, to the window area. 17. The X-ray imaging apparatus according to claim 13, wherein when a point is input through the input device, the at least one processor is configured to create a circle whose center point is the point input through the input device, and increase a radius of the circle in proportion to a time period for which the point is input. 18. The X-ray imaging apparatus according to claim 17, wherein the at least one processor is configured to set a circle having a radius acquired at time at which the point is no longer input, to the window area. 19. The X-ray imaging apparatus according to claim 13, wherein the plurality of blades are configured to perform at least one movement of a rotational movement and a linear movement. 20. The X-ray imaging apparatus according to claim 13, wherein the at least one processor is further configured to perform shutter processing on a remaining area in the acquired X-ray image except for an area occupied by the circle by the n number of the point or cut off the remaining area, to generate an X-ray image corresponding to the window area. 21. A method of controlling an X-ray imaging apparatus, comprising:displaying a guide image on a display;receiving n number of input points for the guide image from a user, wherein n is an integer that is equal to or greater than 3; andsetting a polygon defined by the n number of input points to a window area, and controlling a collimator including a plurality of blades to form a collimation area corresponding to the window area, wherein at least one blade of the plurality of blades is rotatable in a clockwise direction or in a counterclockwise direction,wherein the controlling the collimator comprises:controlling the collimator to form a collimation area having a shape of the polygon defined by the n number of input points, the collimator controlled to perform at least one movement of a rotational movement and a linear movement of at least one of the plurality of blades to place intersection points of the plurality of blades at locations of the n number of input points, respectively; andcontrolling the collimator to form a collimation area of a shape most similar to the polygon defined by the n number of input points, in response to determining that the intersection points of the plurality of blades cannot be placed at the locations of the n number of input points, respectively, by any of the at least one movement of the rotational movement and the linear movement of the at least one of the plurality of blades. 22. The method according to claim 21, wherein the controlling of the collimator to form the collimation area of the shape most similar to the polygon defined by the n number of input points comprises:acquiring an X-ray image corresponding to the collimation area of the shape most similar to the polygon defined by the n number of input points, andcontrolling the collimator to perform image processing on an acquired X-ray image. 23. A method of controlling an X-ray imaging apparatus, comprising:displaying a guide image on a display;receiving n number of a point for the guide image, the n number of the point input by a user, wherein n is an integer that is equal to or greater than 1; andsetting a circle defined by the n number of the point to a window area;controlling a collimator including a plurality of blades to form a collimation area in a shape of a polygon including the window area, wherein at least one blade of the plurality of blades is configured to be rotatable in a clockwise direction or in a counterclockwise direction;in response to determining that the collimator cannot form a collimation area having a shape of the circle defined by the n number of the point, controlling the collimator to form the collimation area in a shape of a square of which one side has a length equal to a diameter of the circle defined by the n number of the point; andperforming image processing on an X-ray image acquired by X-rays passed through the collimation area to acquire an X-ray image corresponding to the window area. 24. The method according to claim 23, wherein the performing the image processing comprises performing shutter processing on a remaining area in the acquired X-ray image except for an area occupied by the circle by the n number of the point or cutting off the remaining area, to generate an X-ray image corresponding to the window area.