Medical stereotaxic appts. - with spots from triple reflected laser beam focused together on target to provide accurate positioning

摘要

The apparatus is used for medical stereotaxy and comprises a tube (1) holding a source of ionising rays (2). A laser beam (5) is projected in from one side, being reflected by a mirror (6) into the axial plane (R1) of the tube. The combined ionising/laser beam (F2) is focused through a plate (7) onto a target (9) over the patient's skull, forming a spot of light. This is reflected back to a reflector on the tube focusing plate and then re-reflected onto the target as a third spot. When the three spots are in alignment, the ionising beam is accurately positioned and perpendicular to the target.