  We have obtained sub-arcsec mid-IR images of a sample of debris disks within
100 pc. For our sample of nineteen A-type debris disk candidates chosen for
their IR excess, we have resolved, for the first time, five sources plus the
previously resolved disk around HD 141569. Two other sources in our sample have
been ruled out as debris disks since the time of sample selection. Three of the
six resolved sources have inferred radii of 1-4 AU (HD 38678, HD 71155, and HD
181869), and one source has an inferred radius ~10-30 AU (HD 141569). Among the
resolved sources with detections of excess IR emission, HD 71155 appears to be
comparable in size (r~2 AU) to the solar system's asteroid belt, thus joining
Zeta Lep (HD 38678, reported previously) to comprise the only two resolved
sources of that class. Two additional sources (HD 95418 and HD 139006) show
spatial extent that implies disk radii of ~1-3 AU, although the excess IR
fluxes are not formally detected with better than 2-sigma significance. For the
unresolved sources, the upper limits on the maximum radii of mid-IR disk
emission are in the range ~1-20 AU, four of which are comparable in radius to
the asteroid belt. We have compared the global color temperatures of the dust
to that expected for the dust in radiative equilibrium at the distances
corresponding to the observed sizes or limits on the sizes. In most cases, the
temperatures estimated via these two methods are comparable, and therefore, we
see a generally consistent picture of the inferred morphology and the global
mid-IR emission. Finally, while our sample size is not statistically
significant, we notice that the older sources (>200 Myr) host much warmer dust
(T > 400 K) than younger sources (in the 10s of Myr).
