apparatuses are disclosed for separating substantially parallel freespace optical beams whose origins are geometrically close . the freespace optical beams originate from a waveguide substrate . a cube shaped mirror substrate is positioned sufficiently close to the waveguide substrate to prevent the freespace optical beams from overlapping as they diverge and thereby minimizes optical cross talk . this assembly allows different freespace optical to be treated and acted upon independently . thus , different optical components may be inserted in the separated freespace optical beams .