Patent ID: 7003004

Claim:
A master write holographic printer comprising a pulsed multiple colour laser system, said pulsed multiple colour laser system comprising: a first active laser element provided in a first laser cavity, said first active laser element comprising Nd:YLF and wherein said first active laser element is arranged to generate laser radiation at a first fundamental frequency; means for arranging the laser mode within said first laser cavity to be single longitudinal mode; means for frequency doubling said laser radiation at said first fundamental frequency to provide laser radiation at a first frequency doubled frequency; means for frequency trebling said laser radiation at said first fundamental frequency to provide laser radiation at a first frequency trebled frequency; a second active laser element provided in a second laser cavity separate from said first laser cavity, said second active laser element comprising Nd:YLF and wherein said second active laser element is arranged to generate laser radiation at a second fundamental frequency; means for frequency doubling said laser radiation at said second fundamental frequency to provide laser radiation at a second frequency doubled frequency; and means for arranging the laser mode within said second laser cavity to be single longitudinal mode.