Editing Collimator (section)

{{Short description|Device that narrows or straightens a beam of particles or waves}}
{{Refimprove|date=June 2010}}

[[File:ParticleCollimator.svg|thumb|300px|Example of a particle collimator]]
A '''collimator''' is a device which narrows a beam of particles or waves. To narrow can mean either to cause the directions of motion to become more aligned in a specific direction (i.e., make [[collimated light]] or [[parallel (geometry)|parallel]] rays), or to cause the spatial [[cross section (geometry)|cross section]] of the beam to become smaller ('''beam limiting device''').