Patent Number: 
Section: claims

1. An X-ray apparatus, comprising: an X-ray tube;  a solid state flat detector opposing said X-ray tube across a patient being examined, the patient defining a body axis;  an X-ray limiting device for limiting X-rays from said X-ray tube;  a driver for rotating said X-ray tube and said X-ray limiting device about a stationary axis disposed above the patient and extending parallel to the body axis, wherein the driver rotates said X-ray tube and said X-ray limiting device in an arc defining a plane oriented perpendicularly to the body axis;  an edge detector for detecting x-rays irradiated onto an edge part of said solid state flat detector; a controller for receiving a signal from said edge detector and controlling, with said signal, said X-ray limiting device so that X-rays do not go outside of said solid state flat detector. 2. An X-ray apparatus according to the  claim 1 , wherein said edge detector comprises X-ray semiconductor elements in edge parts of said solid state flat detector. claim 1 3. An X-ray apparatus according to the  claim 1 , wherein said edge detector comprises a separate X-ray detector from said solid state flat detector. claim 1 4. An X-ray apparatus according to the  claim 1 , further comprising: claim 1 a handle for providing signals depending on an amount of manipulation set by an operator;  an X-ray tube rotation controller for rotating said X-ray tube depending on said signals. 5. An X-ray apparatus according to the  claim 1 , wherein said X-ray limiting device having two shield blades which limit X-rays in a direction which is perpendicular to a body axis of said person. claim 1 6. An X-ray apparatus according to the  claim 5 , further comprising: claim 5 a handle for providing signals depending on an amount of manipulation set by an operator;  a shield blade movement controller for moving said two shield blades in opposite directions from each other, depending on said signals. 7. An X-ray apparatus according to the  claim 5 , further comprising: claim 5 two handles for providing signals depending on amounts of manipulation set by an operator;  a shield blade movement controller for moving said two shield blades independently, depending on said signals. 8. An X-ray apparatus according to the  claim 1 , further comprising: claim 1 a detector for detecting a rotation angle of said X-ray tube, and providing a signal related to said rotation angle;  a controller for receiving said signal from said detector and controlling said X-ray limiting device so that X-rays from said X-ray tube do not go outside of said solid state flat detector. 9. An X-ray apparatus according to  claim 1 , wherein the X-ray tube and the X-ray limiting device are connected to each other. claim 1 10. An X-ray apparatus according to  claim 9 , wherein the X-ray tube and the X-ray limiting device are simultaneously rotated by the driver about the arc. claim 9 11. An X-ray apparatus, comprising: an X-ray tube;  a solid state flat detector opposing said X-ray tube across a patient being examined, the patient defining a body axis;  an X-ray limiting device for limiting X-rays from said X-ray tube;  a driver for rotating said X-ray tube and said X-ray limiting device about a stationary axis disposed above the patient and extending parallel to the body axis in an arc defining a plane oriented perpendicularly to the body axis;  a detector for detecting a rotation angle of said X-ray tube, and providing a signal related to said rotation angle; and  a controller for receiving said signal from said detector and controlling said X-ray limiting device so that X-rays from said X-ray tube do not go outside of said solid state flat detector,  wherein said controller calculates a permissible aperture size defined as a distance between a center of an X-ray irradiation field and an edge of said solid state flat detector, and controlling said X-ray limiting device so that an outer half of X-rays from said X-ray tube is limited to within said permissible aperture size. 12. An X-ray apparatus according to the  claim 11 , wherein said X-ray limiting device has two shield blades which move along a plane which is perpendicular to a body axis, said blades limiting the X-rays. claim 11 13. An X-ray apparatus according to the  claim 12 , further comprising: claim 12 a handle for providing signals depending on an amount of manipulation set by an operator;  a shield blade movement controller for moving the two shield blades in opposite directions from each other, depending on said signals. 14. An X-ray apparatus according to the  claim 11 , further comprising: claim 11 two handles for providing signals depending on amounts of manipulation set by an operator;  a shield blade movement controller for moving two shield blades independently, depending on said signals. 15. An X-ray apparatus, comprising: an X-ray tube;  a solid state flat detector opposing said X-ray tube across a patient being examined, the patient defining a body axis;  an X-ray limiting device for limiting X-rays from said X-ray tube;  a driver for rotating said X-ray tube and said X-ray limiting device about a stationary axis disposed above the patient and extending parallel to the body axis in an arc defining a plane oriented perpendicularly to the body axis;  a detector for detecting a rotation angle of said X-ray tube, and providing a signal related to said rotation angle; and  a controller for receiving said signal from said detector and controlling said X-ray limiting device so that X-rays from said X-ray tube do not go outside of said solid state flat detector,  wherein said controller calculates a permissible aperture size based on an angle between an edge of said solid state flat plate detector and a center of an X-ray irradiation field, and controlling said X-ray limiting device so that an outer half of X-rays from said X-ray tube is limited to within said permissible aperture size.