Methods and apparatus for managing thermal loads on a laser gain medium
and for boosting the output power of a diode pumped laser are disclosed.
The short-term average pumping power to the gain medium is increased, to
provide a burst of pumping energy to the laser gain medium. A subsequent
short-term reduction in the average pumping power then allows the gain
medium to cool to a desired state steady level. The average pumping power
is then increased to maintain this steady state level until the next
burst is desired. For example, a pulse of current may be applied to a
laser diode at a first current level I.sub.1 for a first time interval
.DELTA.t.sub.1, where I.sub.1 exceeds a nominal current value I.sub.nom
by an amount .DELTA.I.sub.1. The current to the laser diode is reduced to
a second current level I.sub.2 for a second time interval .DELTA.t.sub.2,
where I.sub.nom exceeds I.sub.2 by an amount .DELTA.I.sub.2. To balance
the thermal load on the diode an integral of .DELTA.I.sub.1 over the time
.DELTA.t.sub.1 is approximately equal in magnitude to an integral of
.DELTA.I.sub.2 over the time .DELTA.t.sub.2. After applying the pulse of
current at the first current level I.sub.1, and before or after reducing
the current to the second level I.sub.2, the nominal current is applied
to the laser diode for a third time interval .DELTA.t.sub.3.