Patent Number: 
Section: claims

1. A diaphragm unit for use in an x-ray device of the type having an x-ray emitter positioned in a housing, comprising an assembly unit allowing for rotational movement of the diaphragm unit about the housing, so that the assembly unit isocentrically translates the diaphragm unit in its entirety about a source point of the x-ray emitter, allowing an asymmetrical part of an examination area to be irradiated by the x-ray emitter using the diaphragm unit. 2. The diaphragm unit according to claim 1, wherein the assembly unit includes a guide rail for moving the diaphragm unit along a path always equidistant from the source point of the x-ray emitter. 3. The diaphragm unit according to claim 1, further comprising an electric motor for powering rotational movement of the diaphragm unit about the housing. 4. An x-ray device, comprising:an x-ray emitter; anda diaphragm unit arranged on an assembly unit and facing the x-ray emitter for fading in an examination area, wherein the assembly unit is configured to isocentrically rotate the diaphragm unit about the x-ray emitter so that an asymmetrical examination area is irradiated by the x-ray emitter. 5. The x-ray device according to claim 4, wherein components of the diaphragm unit do not change position relative to one another while the assembly unit is rotated. 6. The x-ray device according to claim 4,wherein the x-ray emitter includes a source point from which an axis of symmetry extends;wherein x-rays travel from the source point; along the axis of symmetry and through an exit opening of the emitter; andwherein the diaphragm unit and the x-ray emitter form one integrated unit which can be tilted in the entirety about the source point to thereby rotate the axis of symmetry. 7. The x-ray device according to claim 6, further including a housing surrounding the emitter and a hanger assembly connecting the emitter to the housing to effect tilting of the integrated unit about the source point so that an asymmetrical part of an examination area to be irradiated by the x-ray emitter can be exposed to the x-ray emitter. 8. The x-ray device according to claim 7, wherein the hanger assembly includes a swivel arm for tilting the integrated unit. 9. The diaphragm unit according to claim 4, further comprising a guide rail for moving the diaphragm unit. 10. The diaphragm unit according to claim 9, wherein the guide rail is arranged isocentrically relative to the source point of the x-ray emitter. 11. The x-ray device according to claim 4, further comprising an electric motor for powering isocentric rotation of the diaphragm unit about the x-ray emitter. 12. A method of adjusting a diaphragm unit of the type which receives radiation from an x-ray emitter in order to effect fading in an examination area to be irradiated by the x-ray emitter, the method including the steps of:connecting an assembly unit to provide a rotational path about a source point of the emitter; andconnecting the diaphragm unit to the assembly unit for movement along the rotational path and about the x-ray emitter so that an asymmetrical part of the examination area is exposed to the radiation by moving the diaphragm unit.