VCSELs produce a coherent, symmetrical beam that is even on all planes, experiences no astigmatism, and emits power within a tight spectrum of wavelengths [confirm]. With low divergence, only simple, low-cost optics are required to create a more focused output beam, enabling highly efficient power transmission and greater resolution for communications and sensing applications.
VCSELs are highly efficient compared to LEDs and EELs. As can be seen in the graph, LEDs and EELs are only able to utilize a limited percentage of the output power even when a large aperture is used. VCSELs achieve 100% [full?] power transmission with a tight aperture, enabling a focused output beam with higher efficiency and greater precision.