Aligning and testing alignment of optical elements in a laser beam
delivery system using non-visible radiation. An alignment mirror replaces
a beam redirection mirror and includes a fluorescing substrate and a
dielectric coating on an incident face of the fluorescing substrate that
reflects a major part of an incident laser beam along a next leg of the
beam path and transmits a part of the beam into the fluorescing
substrate, which is transmissive to visible radiation and fluoresces when
irradiated by the beam to emit a visible light image from a back face of
the alignment mirror. An alignment target on the back face indicates a
preferred point of incidence of the beam on the alignment mirror for a
desired alignment of the at least one laser beam. A lens may be tested
and the properties of the lens determined by use of a fluorescing target
plate.