Modal characterization of 940 nm VCSELs for 3D-sensing and LiDAR application

Abstract

Due to increasing demands in 3D-sensing solutions, e.g. face recognition in mobiles and light detection and ranging (LiDAR) in autonomous cars, 940 nm vertical-cavity surface-emitting lasers (VCSELs) as unique light sources play an essential role in industrial utilizations. Therefore, it is necessary to study the modal characterization of 940 nm VCSELs with considering various physical parameters to meet the required usage situations. Self-heating and temperature dependence of these devices are the most important factors that affects the performance of the 3D-sensing. In this thesis, VCSELs with different oxide aperture diameters have been studied. For each VCSEL, output power and voltage as a function of bias current (IPV), optical spectrum and 2D far-field mode profile were measured. All measurements were done at different temperatures and under continues-wave (CW) and pulse current operations. Finally, the output data are analyzed and reported in this thesis.