A laser (126) and an AOM (10) are pulsed at substantially regular
and substantially similar constant high repetition rates to provide working laser
outputs (40) with variable nonimpingement intervals (50) without
sacrificing laser pulse-to-pulse energy stability. When a working laser output
(40) is demanded, an RF pulse (38) is applied to the AOM (10)
in coincidence with the laser output (24) to transmit it to a target. When
no working laser output (40) is demanded, an RF pulse (38) is applied
to the AOM (10) in noncoincidence with the laser output (24) so it
gets blocked. So the average thermal loading on the AOM (10) remains substantially
constant regardless of how randomly the working laser outputs (40) are demanded.
The AOM (10) can also be used to control the energy of the working laser
output (40) by controlling the power of the RF pulse (38) applied.
When the RF power is changed, the RF duration (44) of the RF pulse (38)
is modified to maintain the constant average RF power. Consistent loading on the
AOM (10) eliminates deterioration of laser beam quality and laser beam pointing
accuracy associated with thermal loading variation on the AOM (10) and is
advantageous for applications such as IC chip link processing where stable working
laser outputs (40) with variable output intervals (50) are needed.