Single lobe operation of a 40‐element GaAlAs gain guided coupled stripe array emitting 500 mW cw is obtained in an external ring laser cavity. The cavity arrangement is equivalent to self‐injection locking of the array by its own output, which is first spatially filtered by a single mode fiber. Diffraction‐limited lobe width of 0.13° and single mode operation are demonstrated with a 90 mW single mode fiber output.