A novelty external-cavity is designed to improve beam quality aim at broad area laser diode (BALD). The external-cavity is composed with р?але mirror and blazed diffraction grating. With this kind of setup, a laser beam is obtained with 0.53° far field divergence angle, which corresponding to 1.3 times the diffraction limit, 320 mW output power, spectral line width of 0.02 nm when drive current is 2.7 times threshold current.