Non-parallel etched facet diode laser arrays: Fabrication analysis and characterization

Beam steering has been pursued by researchers for many years. Lateral control of a beam is a very practical capability which would increase the reach and capabilities of diode lasers. This elusive goal of beam direction control is one clear direction of research which has not seen advances comparable to the advances seen in recent years by other areas of diode laser operation. In this thesis we explore a novel technique for attaining beam steering, this novel device design is based on an array of laser diodes. The array may be used in the near and far-field in the near field. Using the far-field, the beam directions are fixed, stable, single mode, and capable of simultaneous and random access operation. Results of an 11 element fan laser represent a factor of 3 performance improvement over all previous beam steering methods. Concentrating on the near-field, the thermal cross-talk characteristics of angled etched facet lasers will be experimentally compared to parallel laser arrays. We demonstrate ultimately a one order of magnitude decrease in the effective thermal cross-talk compared to parallel arrays with comparable minimum facet separation. The effect of facet roughness on the performance of etched-facet diode lasers, as well as the thermal cross-talk characteristics of angled etched-facet lasers are analyzed. Finally, we demonstrate a novel 2D laser beam scanner by integrating a beam steering laser and a micro-electro-mechanical mirror fabricated on a silicon substrate. The system is capable of reading and writing operations, generating or detecting arbitrary patterns in the scanned area. Results demonstrate the feasibility of multi-beam writing in printer systems or multi-line tracking on data retrieval from optical disks.