High-Power Vertical Cavity Laser Diode Arrays for Space Applications

Instead of making incremental improvements to the inherent weakness of the laser facet, Aerius Photonics proposes to fabricate space-qualifiable laser pump arrays that eliminate the weakness of the facet altogether by using kilowatt-capable vertical-cavity surface-emitting lasers (VCSELs), which use a distributed mirror, effectively decoupling the feedback mirror from the output window. When compared to edge-emitting laser arrays, VCSELs offer (1) lower power density at the exit aperture, reducing hotspots, (2) simplified optics, (3) a single solder interface, (4) arbitrary array shape, (5)lower wavelength drift over temperature, and (6) a lower inherent production cost due to their ease of processing and testing. At the end of a successful Phase II, Aerius will deliver arrays with an emission wavelength of 808 nm and an output power of greater than 1000W per bar stack and demonstrating high reliability in a high vacuum environment. In Phase I, they performed baseline reliability studies of kilowatt-capable VCSEL arrays in vacuum and demonstrated their compatibility with space environments. In addition, Aerius’ VCSEL arrays demonstrated radiation hardness when exposed to ionizing radiation and proton irradiation.