Patent Number: 
Section: claims

1. An X-ray shielding apparatus having an adjustable X-ray passage, the X-ray shielding apparatus comprising:a stationary member having an aperture;one or more shielding members movable in relation to the stationary member and made from an X-ray shielding material, the one or more shielding members having openings defining an X-ray passage within the aperture that is smaller than the aperture, wherein the movement of the one or more shielding members is restricted such that the one or more shielding members in each position relative to the stationary member cover the aperture at least in an area outside the X-ray passage; anda tube member constituted by an X-ray lens or configured to receive an X-ray lens, wherein one of the one or more shielding members is mounted on the tube member such that the tube member extends through the opening of this shielding member and through the aperture of the stationary member. 2. The X-ray shielding apparatus of claim 1, further comprising a guiding mechanism for guiding the movement of the at least one shielding member in relation to the stationary member, the guiding mechanism includinga guided element coupled to one of the stationary member and the at least one shielding member; anda guiding structure coupled to the other one of the stationary member and the at least one shielding member, the guiding structure defining a stop for the guided element. 3. The X-ray shielding apparatus of claim 2, wherein the guiding structure is constituted by a rim of the stationary member or of the at least one shielding member. 4. The X-ray shielding apparatus of claim 3, wherein the guiding structure is constituted by a rim of the aperture of the stationary member. 5. The X-ray shielding apparatus of claim 2, wherein the guided element is constituted by a protrusion coupled to the at least one shielding member. 6. The X-ray shielding apparatus of claim 1, wherein the at least one shielding member is disk-shaped. 7. The X-ray shielding apparatus of claim 1, wherein the at least one shielding member is constituted by an annular ring plate. 8. The X-ray shielding apparatus of claim 1, wherein the X-ray shielding apparatus comprises a first shielding member with a first opening and a second shielding member with a second opening, the second opening having a smaller size than the first opening and substantially defining the area of X-ray passage. 9. The X-ray shielding apparatus of claim 8, wherein the first shielding member has a first outer diameter and the second shielding member has a second outer diameter, the second outer diameter being smaller than the first outer diameter. 10. The X-ray shielding apparatus of claim 8, wherein the first and second shielding members are arranged one behind the other and collectively cover the aperture except for the area of the X-ray passage. 11. The X-ray shielding apparatus of claim 8, wherein the tube member extends through the first and second shielding members, and has a diameter that essentially corresponds to the diameter of the smaller one of the first and second openings. 12. The X-ray shielding apparatus of claim 11, wherein an axial position of the tube member relative to one or both of the first and second shielding members is adjustable. 13. An X-ray device comprising:an X-ray source;an X-ray lens for redirecting X-rays emitted from the X-ray source;an X-ray shielding component for selectively transmitting X-rays towards or through the X-ray lens, the X-ray shielding component including a stationary member having an aperture and one or more shielding members movable in relation to the stationary member and made from an X-ray shielding material, the one or more shielding members having openings defining an X-ray passage within the aperture that is smaller than the aperture, wherein the movement of the one or more shielding members is restricted such that the one or more shielding members in each position relative to the stationary member cover the aperture at least in an area outside the X-ray passage, and the X-ray shielding component further comprising a tube member constituted by an X-ray lens or configured to receive an X-ray lens, wherein one of the one or more shielding members is mounted on the tube member such that the tube member extends through the opening of this shielding member and through the aperture of the stationary member. 14. The X-ray device of claim 13, wherein the X-ray lens comprises one or more bundles of capillaries. 15. The X-ray device of claim 13, wherein the X-ray device further comprises a positioning component for the X-ray lens, the positioning component being disposed downstream of the shielding component and being made from a material that is substantially transparent to X-rays.