Laser burst boosting method and apparatus

Abstract

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 Ifor a first time interval Δt, where Iexceeds a nominal current value Iby an amount ΔI. The current to the laser diode is reduced to a second current level Ifor a second time interval Δt, where Iexceeds Iby an amount ΔI. To balance the thermal load on the diode an integral of ΔIover the time Δtis approximately equal in magnitude to an integral of ΔIover the time Δt. After applying the pulse of current at the first current level I, and before or after reducing the current to the second level I, the nominal current is applied to the laser diode for a third time interval Δt.