A method, comprising: receiving, by a first acousto-optic deflector, a laser beam; diffracting, by the first acousto-optic deflector, the received laser beam along a first axis; receiving, by a second acousto-optic deflector, the diffracted laser beam; and diffracting, by the second acousto-optic deflector, the received diffracted laser beam along a second axis, wherein: the first acousto-optic deflector and the second acousto-optic deflector are separated by a vertical distance; the first acousto-optic deflector is oriented along the first axis; and the second acousto-optic deflector is oriented along the second axis that is different to the first axis; characterised in that the laser beam is comprised of one or more pulses, and the method further comprises: receiving, by the first acousto-optic deflector, a pulse of the laser beam; diffracting, by the first acousto-optic deflector, the received pulse of the laser beam, along the first axis; receiving, by a third acousto-optic deflector (404,405) that is oriented along the second axis and is separated by the vertical distance from the first acousto-optic deflector, the diffracted pulse of the laser beam; and diffracting, by the third acousto-optic deflector, the received diffracted pulse of the laser beam along the second axis that is different to the first axis. receiving, by a first acousto-optic deflector, a laser beam; diffracting, by the first acousto-optic deflector, the received laser beam along a first axis; receiving, by a second acousto-optic deflector, the diffracted laser beam; and diffracting, by the second acousto-optic deflector, the received diffracted laser beam along a second axis, wherein: the first acousto-optic deflector and the second acousto-optic deflector are separated by a vertical distance; the first acousto-optic deflector is oriented along the first axis; and the second acousto-optic deflector is oriented along the second axis that is different to the first axis; characterised in that the laser beam is comprised of one or more pulses, and the method further comprises: receiving, by the first acousto-optic deflector, a pulse of the laser beam; diffracting, by the first acousto-optic deflector, the received pulse of the laser beam, along the first axis; receiving, by a third acousto-optic deflector (404,405) that is oriented along the second axis and is separated by the vertical distance from the first acousto-optic deflector, the diffracted pulse of the laser beam; and diffracting, by the third acousto-optic deflector, the received diffracted pulse of the laser beam along the second axis that is different to the first axis. the first acousto-optic deflector and the second acousto-optic deflector are separated by a vertical distance; the first acousto-optic deflector is oriented along the first axis; and the second acousto-optic deflector is oriented along the second axis that is different to the first axis; characterised in that the laser beam is comprised of one or more pulses, and the method further comprises: receiving, by the first acousto-optic deflector, a pulse of the laser beam; diffracting, by the first acousto-optic deflector, the received pulse of the laser beam, along the first axis; receiving, by a third acousto-optic deflector (404,405) that is oriented along the second axis and is separated by the vertical distance from the first acousto-optic deflector, the diffracted pulse of the laser beam; and diffracting, by the third acousto-optic deflector, the received diffracted pulse of the laser beam along the second axis that is different to the first axis. receiving, by the first acousto-optic deflector, a pulse of the laser beam; diffracting, by the first acousto-optic deflector, the received pulse of the laser beam, along the first axis; receiving, by a third acousto-optic deflector (404,405) that is oriented along the second axis and is separated by the vertical distance from the first acousto-optic deflector, the diffracted pulse of the laser beam; and diffracting, by the third acousto-optic deflector, the received diffracted pulse of the laser beam along the second axis that is different to the first axis.