  We present ground-based observations of the disk around the A-type star
$\beta$ Pictoris to perform a close inspection of the inner disk morphology.
Images were collected with NACO, the AO-assisted near-IR instrument on the VLT
(ESO) which includes two types of coronagraphs: classical Lyot masks and phase
masks. In this program we took advantage of both types of coronagraphs in two
spectral bands, H-band for the Lyot mask and Ks-band for the phase mask. In
addition, we simulated an extended object to understand the limitations in
deconvolution of coronagraphic images. The reduced coronagraphic images allow
us to carefully measure the structures of the debris disk and reveal a number
of asymmetries of which some were not reported before (position, elevation and
thickness of the warp). In this program, the circumstellar material is visible
as close as 0.7" ($13.5 $AU) owing to the phase mask while the Lyot mask
generates artifacts which hamper the detection of the dust at separations
closer than 1.2" ($23.2 $AU). The point source detection limit is compared to
recently published observations of a planet candidate. Finally, the simulations
show that deconvolution of coronagraphic data may indeed produce artificial
patterns within the image of a disk.
