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tokens: measurements in -band for the two prototypes are presented in Fig. 3 . Fig. 3 Azimuthal average of the amplitude transmission in band for the chromium oxide (green) and aluminum (blue) SLLC prototypes as a function of the normalized distance from the apodizer center (). The increase in transmission close to zero corresponds to the pattern introduced in the design to facilitate the opto-mechanical centering of the apodizer. The design specifications are represented by a gray envelope. The transmission of the microdots map designed by Aktiwave is also plotted in orange. This profile appears noisier because the microdots map is binarized. The top plot shows the normalized transmission measurement, and the bottom plot shows the error with respect to the nominal transmission profile. The vertical dotted lines correspond to the radii where we plot the transmission as a function of wavelength in the left panel of Fig. 4 . The transmission map of the aluminum prototype in band is shown as an inset in the top left corner of the plot. Fig. 4 Chromaticity of the amplitude transmission of the aluminum prototype. Left : normalized amplitude transmission as a function of wavelength at different radii in the pupil (dotted vertical lines in Fig. 3 ), for which the value is indicated on the right side of each curve. Right : measured amplitude transmission at the four wavelengths as a function of the original specification. The dashed and dash-dotted lines show the 1 decade/decade and 0.5 decade/decade trends. From the very first measurements it appeared that the chromium oxide prototype did not meet the specifications in the low-transmission part (20%) of the apodizer. Because only one free position was available in the SPHERE apodizer wheel and because limited time was available for extensive tests during the reintegration period, we chose to keep the aluminum prototype inside the instrument, which is closer to the specifications. For this reason, we do not discuss the results from the chromium oxide prototype in more detail, and we refer to Vigan et al. (2014) for some additional information and measurements. From now on, we refer only to the aluminum prototype. For the aluminum prototype, the transmission is closer to the specifications, but there are still some problems in the low-transmission parts of the apodizer. The minimum transmission obtained in the central part and at the edge of the pupil is 2.5%. This measurement illustrates the difficulty of manufacturing apodizers for the near-IR with very high optical densities, as was already identified by previous studies in the context of the GPI instrument ( Sivaramakrishnan et al. 2009 ). A microdots apodizer relies on the absorption and diffraction of light by small (20 m in our case) metallic dots deposited on a substrate whose distribution is such that the density of dots produces the required transmission profile. As detailed by Dorrer Zuegel (2007) , the spatial filtering produced by the