A stage lighting lamp unit includes a processor for receiving control data from
a remote console. Beam orientation data for the lamp unit is passed to the lamp
in the form of the x, y and z co-ordinates of a point in space through which the
beam is to pass. The processor divides the required lamp travel into a number of
stages dependent on execution duration data sent with the position data, and calculates,
for each stage, a new value for pan and tilt angles for the lamp. These values
are passed to pan and tilt controlling co-processors which control servo-motors
for pan and tilt operation. The lamp unit also incorporates a rotatable shutter
for interrupting the lamp beam when required. The shutters of all the lamps in
a system can be instructed from the remote console to open and close in synchronism,
thereby providing a stroboscopic effect.
