Abstract

Vertical-cavity surface-emitting laser (VCSEL) arrays are attractive for applications in parallel, optical signal-processing schemes, and as circular beam, high-power sources. However, one of the limitations of current VCSEL designs is their relatively low output in terms of power per unit area. The straightforward solution—increasing the laser area—is useful over a short range of laser diameters. Lasers with a diameter of 10-20 µm show a multispatial mode of operation, even at relatively low injection currents. Larger lasers are susceptible to formation of filaments, which results in low beam quality and poor coherence. Recently¹ we reported phase locking of two-dimensional VCSEL arrays by patterning the reflectivity of the back mirror of the array. Efficient phase-locking of small arrays (<20 lasers) was demonstrated.

© 1991 Optical Society of America