A simple time-resolved emittance measurement of a laser ion source with a digital camera

We have measured a time-resolved emittance of a laser ion source by a pepper-pot method using a commercially available digital camera for personal use and a micro channel plate detector. The micro channel plate was operated in pulse mode by applying a short pulse of high voltage to the detector. This enabled us to obtain the time-resolved images of the pepper-pot. The ion source is based on irradiation of a frequency-doubled Nd:YAG laser on a copper target. The copper ion beam was extracted from the laser plasma by an induction accelerator Module during 400 ns. The emittance was observed as a function of time between 180 and 380 ns after the extraction voltage was applied. (C) 2001 Elsevier Science B.V. All rights reserved.