Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of threaded drives disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises a plurality of elongate leaves mounted in a carriage, the carriage being mounted on a substrate, wherein the leaves are independently moveable relative to the carriage in a longitudinal direction, and the carriage is moveable in that direction relative to the substrate, and a control apparatus is arranged to receive a signal representing leaf positions relative to the substrate and to control the leaf positions relative to the carriage and the carriage positions relative to the substrate so as to achieve those leaf positions relative to the substrate. Most MLCs sense the current positions of the leaves relative to the substrate. The control apparatus can therefore compare the current leaf positions to the signaled leaf positions, and move the leaves and the carriage accordingly. A corresponding method is also disclosed.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises a plurality of elongate leaves mounted in a carriage, the carriage being mounted on a substrate, wherein the leaves are independently moveable relative to the carriage in a longitudinal direction, and the carriage is moveable in that direction relative to the substrate, and a control apparatus arranged to receive a signal representing leaf positions relative to the substrate and being arranged to control the leaf positions relative to the carriage and the carriage positions relative to the substrate so as to achieve those leaf positions relative to the substrate. By allowing the carriage to be driven concurrently with the leaves, the speed of movement of the carriage can be added to that of the leaves. In this way, where leaves are required to make a long traverse they can do so more quickly.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of threaded drives disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of leadscrews disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.