  This work presents the results of experimental laboratory tests on the
apodization of circular and rectangular apertures using the Interferometric
Apodization by Homothety (IAH) technique. The IAH approach involves splitting
the amplitude of the instrumental PSF into two equal parts. One of the two
produced PSFs undergoes a homothety to change its transverse dimensions while
its amplitude is properly controlled. The two PSFs are then combined to produce
an apodized image. The diffraction wings of the resulting PSF are subsequently
reduced by some variable reduction factor, depending on an amplitude parameter
$\gamma$ and a spread parameter $\eta$. This apodization approach was
implemented in the laboratory using an interferometric setup based on the
Mach-Zehnder Interferometer (MZI). The experimental results exhibit a strong
agreement between theory and experiment. For instance, the average experimental
contrast obtained at a low angular separation of $2.4\lambda/D$ does not exceed
$5\times10^{-4}$. This work also allowed us to study the influence on the
apodizer's performance of some parameters such as the wavelength and the
density of the neutral filters.
