Chromium oxide SLLC prototype during its visual inspection in a clean room at LAM (left), under a binocular microscope (center) and in its final mechanical mount during reintegration of SPHERE in Paranal in 2014 (right). The final SLLC component installed in SPHERE was a second prototype using an aluminum metal layer for the microdots pattern, which increases the optical density in the near-infrared compared to the chromium oxide prototype (see Sect. 2.3).