MULTILEAF COLLIMATOR, AND RADIATION THERAPY APPARATUS AND RADIATION THERAPY SYSTEM USING SAME

摘要

A multileaf collimator includes leaves extending in a first direction; a frame supporting the leaves so that the leaves are advanceable and retractable in a state where the leaves are placed side by side in a second direction perpendicular to the first direction; shafts extending in the second direction and corresponding to the leaves; driving units respectively connected to base ends of the shafts for rotating the shafts around axial lines; and driving units provided at tips of the shafts and contacting portions of the leaves for advancing and retracting the leaves in the first direction by the rotation of the shafts around the axial lines. At least some of the shafts have the same shaft length. The driving units are arranged so that the positions thereof in the second direction are shifted from each other according to the positions of the tips of the shafts having the same length.