US Patent 8971376 Broad area laser pump combiner

Multiple broad area lasers are coupled to a planar lightwave circuit, where the waveguides come together to form a single wide emitting aperture. A tapered lens is used at the output of the planar lightwave circuit to transform the highly asymmetric mode into a conventional round mode. This configuration allows much higher “brightness”, allowing 10 or more 100 um wide broad area lasers to be coupled into a single 100 um core multimode fiber. This is considerably more efficient than the standard method of combining a single 100 um wide broad area laser to a 100 um core multimode fiber.