VCSEL How Was it Born and Grown Since One-Century After Edison?

In this lecture we first present how the basic concept of vertical-cavity surface-emitting laser, VCSEL (pronounced as [vic-cell]) was born in 1977. It was just an inspiration after a considerable struggle to discover a laser that realizes; (i) single mode, (ii) monolithic manufacturability, and (iii) frequency reproducibility. Secondly, we focus on the physics that led to the VCSEL industry today. Thirdly, we describe their mode behaviors for their applications in communication and sensing. Lastly, we survey the VCSEL application systems from high-speed LANs in Data Communications, computer mouse, 3D face recognition in mobile phones, LiDAR in automotive and home appliance and industrial heating and so.