Remotely controlled positioning lasers.

Abstract

Positioning lasers used in radiotherapy generally require little adjustment. When required, this is easy to do for sidelights, but can be difficult and time consuming for ceiling mounted lasers. For this purpose, we have modified a commercial positioning laser by incorporating a device for rotating the alignment adjustment screws. This device is driven by a pair of motors remotely controlled through a cable. Two units have been built and installed. In practice, experience with these drive units has shown that it is now easier to adjust the ceiling lasers than the sidelights. Adjustment sensitivity in both units is considerably better than 1 mm, so there is little problem aligning the laser quickly and accurately.