Progress on vertical-cavity surface-emitting laser arrays for infrared illumination applications

Abstract

For infrared illumination with wavelength range of 808nm-1064nm, vertical-cavity surface-emitting lasers (VCSELs) offer many advantageous properties including superior beam quality (such as low divergence, circular shape beam and speckle-free image), increased eye safety, high reliability and low manufacturing cost. We report our progress on highpower high-efficiency VCSELs and two dimensional (2D) VCSEL arrays for such illumination applications. GaAs-based VCSEL wafers are grown by MOCVD and processed into either top-emitting or bottom-emitting devices depending on the emission wavelength and applications. Results from both single devices and arrays are presented. In particular, record-high power conversion efficiency (PCE) of 63.4% with 300mW output was achieved from VCSELs at 1064nm. Such VCSELs also operate with <55% PCE at 50C. For a 2mm by 10mm array, 56.4% PCE with 150W output was demonstrated. Using those VCSELs and arrays as building blocks, various high power illuminators ranging from a few Watts to over 100 kiloWatts have been fabricated.