A self-setting attenuator for laser pulse energy stabilization

An active optical filter has been developed which when applied to single shot pulsed lasers dramatically improves the pulse to pulse energy reproducibility, essentially eliminating shot to shot fluctuations and day to day drift. The device acts as an intelligent (i.e. self setting) electro optic attenuator, which samples the input laser pulse and applies an appropriate transmission correction to that same laser pulse to give a quasi-constant output energy. The basic insertion loss can be as low as 50%. We present both the design and experimental demonstration of the device.