  We report a high-resolution microscope system for imaging ultracold ytterbium
atoms trapped in a two-dimensional optical lattice. By using the ultraviolet
strong transition combined with a solid immersion lens and high-resolution
optics, our system resolved individual sites in an optical lattice with a
544-nm spacing. Without any cooling mechanism during the imaging process, the
deep potential required to contain the atoms was realized using a combination
of a shallow ground-state and a deep excited-state potentials. The lifetime and
limitations of this setup were studied in detail.
