High beam quality novel vertical cavity surface emitting laser array

Vertical cavity surface emitting laser (VCSEL) array with a novel arrangement is reported. By the modulation of the arrangement of operture size and the center spacing of the units, we obtain high power density up to 1 kW/cm² and good beam property of Gaussian far-field distribution. The divergence angle is below 20° in the range of operating current from 0 A to 6 A. This array is composed of 5 symmetrically-arranged elements of 200 μm,150 μm and 100 μm-diameter, with the center spacing of 250 μm and 200 μm respectively. The maximum power is 880 mW at a current of 4 A with the wall-plug efficiency of 0.3 W/A. The differential resistance is 0.09 Ω with a threshold of 0.56 A. By the comparison between the novel array and the 4×4 two-dimensional array with the same total lasing area, we can conclude that the novel array is better in the property of output power, threshold current, lasing spectra, far-field distribution etc. The theoretical simulation of the near-field and far-field distribution is in good agreement with the experimental results.