A direct write holographic printer for producing RGB color reflection
holograms is disclosed. A Nd:YLF crystal (1) in a laser cavity is excited
to produce an emission at 1313 nm which is frequency converted by
doubling to 656.5 nm and by tripling to 437.7 nm. In a separate cavity a
similar Nd:YLF crystal (1a) is synchronously or asynchronously excited to
produce an emission at 1047.1 nm (or at the related line of 1053 nm)
which is frequency converted by doubling to 523.6 nm (or 526.5 nm). The
emissions at 437.7 nm and 656.5 nm are combined co-linearly with the
emission at 523.6 nm (or 526.5 nm) to produce a single RGB pulsed laser
beam.