Patent ID: 8270569

Claim:
A modulation system for modulating a radiation beam toward a target, comprising: a plurality of cascaded modulators; a positioner operable to change positions of each of said modulators between in-beam and out-of-beam positions, wherein in said in-beam position said modulator is in a path of a radiation beam for at least a majority of a total cross-section of said beam and in said out-beam position said modulator is not in the path of the radiation beam; and a processor in communication with a beam modifier and with said positioner operative to determine operating times or motion speed for changing the respective positions of said modulators between said in-beam and out-of-beam positions, wherein said beam modifier is operable to change during irradiation an aperture of said radiation beam and said positioner is operative to change during irradiation a relative position of said target and said radiation beam.