An assembly for providing a concentrated, vertically stacked array of
laser beams from a horizontally offset array of electrically
serially-connected metallic microchannel heat sinks each bearing a laser
diode bar. The heat sinks are mounted on horizontally offset planes of
the manifold which has coolant channels serving adjacent heat sinks that
are separated from each to increase the electrical resistance of the
fluid path between adjacent ones of said heat sinks. Stepped optical
deflectors re-arrange the horizontally emitted laser beams into vertical
stack.