  We present our results from a mid-infrared interferometric survey targeted at
the planet-forming region in the circumstellar disks around low- and
intermediate-mass young stars. Our sample consist of 82 objects, including T
Tauri stars, Herbig Ae stars, and young eruptive stars. Our main results are:
1) Disks around T Tauri stars are similar to those around Herbig Ae stars, but
are relatively more extended once we account for stellar luminosity. 2) From
the distribution of the sizes of the mid-infrared emitting region we find that
inner dusty disk holes may be present in roughly half of the sample. 3) Our
analysis of the silicate spectral feature reveals that the dust in the inner
$\sim$1 au region of disks is generally more processed than that in the outer
regions. 4) The dust in the disks of T Tauri stars typically show weaker
silicate emission in the N band spectrum, compared to Herbig Ae stars, which
may indicate a general difference in the disk structure. Our data products are
available at VizieR, and at the following web page:
http://konkoly.hu/MIDI_atlas
