A
laser in which the state of the device introducing important losses in the resonant cavity
and preventing
lasing operation is suddenly switched to a state where the device introduces very low losses.
This increases rapidly the Quality factor of the cavity, allowing the build-up of
a short and very intense
laser pulse. Typical pulse durations are in the ns range. The Q-switching may be active
(a rotating mirror or electro-optic device) or passive (a saturable
absorber).
Source:
PAC, 1996, 68, 2223
(Glossary of terms used in photochemistry (IUPAC Recommendations 1996))
on page 2266