Abstract

In recent years, the practice of aligning objects with the aid of a projected line of light has seen rapid expansion. Line-beam and cross-beam generators incorporating low-power He-Ne lasers and cylindrical lenses are readily available on the commercial market. Alignment devices that diverge the beam by refraction are generally more popular than complicated systems that sweep the beam into a line with rotating mirrors or prisms, in the medical field, refractive devices are commonly used for positioning patients during diagnostic scanning procedures.

© 1985 Optical Society of America