Digital beam steering from surface-emitting laser diodes based on surface mode emission

摘要

We present a surface emitting GaAs/AlGaAs laser diode beam steering device based on the surface mode emission (SME) technique. The SME-laser diodes operate in a single-mode and show efficient surface emission into a single beam with a minimum beam divergence of 0.11$DGR@. We demonstrate a large digital beam steering from this device, which is achieved by mode switching. The special SME-structure supports two single-mode emission wavelengths, which are spaced by 8.38 nm. Digital switching between these two modes by a proper current pulse sequence leads to a steering of the surface emitted single-beam by 4.9$DGR@. Presently the beam steering frequency is limited to a maximum value of 0.15 MHz. An optimized device design for a continuous steering of the single, surface emitted beam is proposed.