Experimental research of spectrally beam combined diode laser based on grating-cavity

In order to study spectral beam combining of a laser diode array (LDA) based on grating-cavity, coupling efficiency model with abaxial aberration was adopted to analyze the effect of the system parameters on the coupling efficiency. The coupling efficiency decreased when abaxial distance or the order of mode increased, and the linewidth of emitters could be compressed to 0.05nm. A LDA comprised of 19 emitters was spectrally combined by means of grating-cavity with 10.1W CW output power,0.45W/A slope efficiency and beam quality factor Mx2 of 17.6 along the slow axis. Spectrum width of the LDA was broaden to 15nm,and linewidth of a single emitter was compressed to 0.1nm. It is shown that spectral beam combining can improve beam quality of a LDA and narrow linewidth of emitters.