Assembly and test results of the AOF laser guide star units at ESO

The Four Laser Guide St ar Facility (4LGSF) is part of the ESO Adaptive Optics Facility, in which one of the VLT telescopes, UT4, is transformed in an adaptive telescope - equipped with a deformable secondary mirror, two adaptive optics systems at the Nasmyth focii and four sodium laser guide star modular units. In this paper we present the design, the assembly and val idation test performed so far in Europe on the first laser guide star unit. Keywords: Laser guide stars, adaptive optics, laser launch optics, optical testing