A breadboard for beam shaping of high-power laser diode arrays (LDAs)
has been realized. The coherent beams are added with the aid of a cont
inuous surface-relief fan-in element. It results in a nearly symmetric
single lobed beam of collimated light with maximum conversion efficie
ncy. The theoretical efficiency is determined to be 96-7%. Experimenta
lly, one third of the total power is now in the central peak.