Patent Number: 
Section: claims

1. A filter device for a collimator of an irradiation device, comprising:a plurality of filter disks, arranged on a disk rotatable around an axis, each respective filter disk, of the plurality of filter disks, being mounted so as to be movable in a radial direction and being tensioned via a respective spring element radially away from the axis or toward the axis against a guide contour, to effect a radial movement of at least one filter disk of the plurality of filter disks. 2. The filter device as claimed in claim 1, wherein at least the filter disks, arranged adjacent to the axis, overlap in sections. 3. The filter device of claim 1, wherein the guide contour, to guide the plurality of filter disks tensioned away from the axis, is embodied as a path-shaped, rounded guide contour surrounding the plurality of filter disks. 4. The filter device of claim 3, wherein the guide contour is curved convexly outward in at least one section. 5. The filter device of claim 4, wherein the plurality of filter disks include three filter disks, and wherein the guide contour is embodied in an oval shape. 6. The filter device of claim 1, wherein the guide contour, to guide the plurality of filter disks tensioned toward the axis, is embodied as a disk-shaped, rounded guide contour arranged inside the filter disks arranged around the guide contour. 7. The filter device of claim 6, wherein the guide contour is curved convexly outward in at least one section. 8. The filter device of claim 7, wherein the plurality of filter disks include three filter disks, and wherein the guide contour is embodied in an oval shape. 9. The filter device of claim 1, wherein each filter disk, of the plurality of filter disks, is accommodated in a linear, radially directed guide arranged on the disk. 10. The filter device of claim 1, wherein compression springs are provided as spring elements. 11. The filter device of claim 1, wherein each filter disk, of the plurality of filter disks, consists of a frame and a disk filter inserted into the frame. 12. A collimator, comprising:the filter device of claim 1. 13. An irradiation device, comprising:a radiation source;a radiation receiver; andthe collimator of claim 12. 14. The filter device of claim 1, wherein the guide contour, to guide the plurality of filter disks tensioned away from the axis, is embodied as a path-shaped, rounded guide contour surrounding the plurality of filter disks. 15. The filter device of claim 14, wherein the guide contour is curved convexly outward in at least one section. 16. The filter device of claim 15, wherein the plurality of filter disks include three filter disks, and wherein the guide contour is embodied in an oval shape. 17. The filter device of claim 2, wherein the guide contour, to guide the plurality of filter disks tensioned toward the axis, is embodied as a disk-shaped, rounded guide contour arranged inside the filter disks arranged around the guide contour. 18. The filter device of claim 17, wherein the guide contour is curved convexly outward in at least one section. 19. The filter device of claim 18, wherein the plurality of filter disks include three filter disks, and wherein the guide contour is embodied in an oval shape. 20. A collimator, comprising:the filter device of claim 2.