The
photon irradiance,
,
integrated over the time of
irradiation
(
, simplified expression:
when the
photon irradiance is constant over the time considered).
The SI unit is
.
Alternatively, the term can be used with the amount of photons (mol or its equivalent
einstein), the SI unit then being
.
For a parallel and perpendicularly incident beam, not scattered or reflected by the target or its surroundings,
photon fluence
is an equivalent term.
Source:
PAC, 1996, 68, 2223
(Glossary of terms used in photochemistry (IUPAC Recommendations 1996))
on page 2262
