Editing Mirror galvanometer (section)

== Modern uses ==
{{refimprove-section|date=July 2014}}
{{see also|Laser scanning}}
[[File:Laser galvo.jpg|thumb|Mirror galvo in an RGB [[laser projector]].]]
[[File:Spot Galvanometer picture.png|thumb|right|200px|"EdSpot", a popular commercial mirror galvanometer, somewhat resembles this picture.]]

In modern times, high-speed mirror [[galvanometer]]s are employed in [[laser light shows]] to move the laser beams and produce colorful geometric patterns in fog around the audience. Such high speed mirror galvanometers have proved to be indispensable in industry for [[laser marking]] systems for everything from laser etching hand tools, containers, and parts to batch-coding [[Wafer (electronics)|semiconductor wafers]] in [[semiconductor device fabrication]]. They typically control [[Cartesian coordinate system|X and Y directions]] on [[Nd:YAG]] and [[Carbon dioxide laser|CO<sub>2</sub> laser]] markers to control the position of the infrared power laser spot. [[Laser ablation]], [[laser beam machining]] and [[wafer dicing]] are all industrial areas where high-speed mirror galvanometers can be found.

This moving coil galvanometer is mainly used to measure very feeble or low currents of order 10<sup>−9</sup>&nbsp;A.

To linearise the magnetic field across the coil throughout the galvanometer's range of movement, the [[Galvanometer#History|d'Arsonval design]] of a soft iron cylinder is placed inside the coil without touching it. This gives a consistent radial field, rather than a parallel linear field.