Variation of the injection efficiency measured at 642 nm as a function of the focal ratio (bottom horizontal axis), or as a function of the ratio between the PSF size and MFD of the PL (top horizonal axis). For each focal ratio experimentally tested, we represent the on-axis injection efficiency, the maximum efficiency, and the average over the whole scanned area (see the coupling maps). The FoV projected on-sky is also plotted with red crosses (right axis).