In this paper, we demonstrate lateral mode selection and amplification in a broad area laser (BAL) diode in an external cavity. The cavity is based on self-injection locking of an 807 nm, 3W broad area diode using a mirror stripe as the feedback unit. At the optimum mirror stripe position, the lateral far-field intensity profile is narrowed 8.5 times compared with the profile from the freely running laser when running at a drive current of twice the threshold current. We have determined the lateral angular range, in which, different array modes can be exited and, only, within a narrow range around 2.3° from the beam center a high, spatial beam coherence can be obtained.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.