LASER-BEAM PROFILER IN THE VACUUM ULTRAVIOLET SPECTRAL RANGE USING PHOTOSTIMULABLE PHOSPHOR

We propose and demonstrate the use of a photostimulable phosphor material, BaFBr:Eu2+, for recording two-dimensional intensity distributions within output beams of vacuum ultraviolet lasers. The sensitivity characteristics were measured not only for nanosecond pulsed radiation from KrF, ArF, and Ar2 excimer lasers but also for quasi-continuous-wave synchrotron radiation. We designed and constructed a laser beam profiler to record, read, and erase images in vacuum. The intensity distribution in the output beams from an Ar2 excimer laser was measured with it, and then the threshold gas pressure for obtaining the well collimated beams was found to be 22 kg/cm2. The intensity is not uniform in the beams but stronger in the peripheral part than in the central one.