According to one aspect of the present invention, an apparatus for optically
combining light beams is disclosed. The apparatus includes a set of prism shaped
doorways configured to receive output beams from at least one optical device. Each
of the plurality of doorways has a common refractive index. The apparatus also
includes a set of spherical mirrors disposed substantially parallel to the plurality
of doorways. Each mirror is associated with one of the plurality of doorways. The
apparatus further includes a boundary layer disposed between the set of doorways
and the set of mirrors. The boundary layer has a refractive index greater than
the common refractive index of the plurality of doorways. The common refractive
index of the set of doorways and the refractive index of the boundary layer are
configured to change the angle of each of the received output beams to combine
the set of received output beams into a single output beam.