Since April 2016, the 4 Laser Guide Star Facility (4LGSF) has been installed at the ESO's Very Large Telescope (VLT), as a new subsystem of the Adaptive Optics Facility (AOF). The 4LGSF is a complement of the VLT Laser Guide Star Facility (LGSF). Instead of a single laser beam, the 4LGSF propagates four laser beams into the skies of Paranal, in northern Chile, producing four artificial stars by illuminating sodium atoms located in the atmosphere at 90 km altitude. These four stars enable getting a better correction in a specific direction, or widening the field of view corrected by an adaptive optics. Each laser delivers 22 watts in a diameter of . The 4LGSF Laser System is based on a fiber Raman laser technology, developed at ESO and transferred to industry.