Control of temporal shape of nanosecond long lasers using feedback loops

We present developments in the control of the temporal pulse shape of nanosecond lasers. An active feedback loop between a regenerative amplified laser's output and input was controlled in order to obtain the desired pulse shape. We used several algorithms to achieve this and the differences caused by the target pulse shape and duration are compared. It is found that the algorithm based on the ratio of the target pulse shape and measured pulse profile provides the most robust solution. The methods proposed here can be used to obtain any pulse shape with minimal knowledge of the laser amplification system.