Laser detection phosphors
are used to detect the presence of lasers in the infra-red region
by converting the energy to visible.
Storage phosphors react
to a broad spectrum of infra-red but require daylight or UV to charge
up the phosphor first. Exposure to infra-red will cause the energy
to be released resulting in a gradual drop in output.
"Anti-Stokes"
phosphors directly convert the energy from infra-red to visible
with a continuous output. They do not exhibit the same broad response
to infra-red though.
