Detailed analyses have been carried out of infrared (\mathbf{H}{3}^{+})images of Jupiter's polar regions observed with the ProtoCam camera on the Infrared Telescope Facility (IRTF) on March 3-6, 1992. The inages were obtained at (3.5 \mu \mathrm{m}), where (\mathrm{H}{3}^{+})emission is strong and the jovian disk is dark. By carefully examining the (\mathrm{H}{3}^{+})emission over the limb of the polar regions, we find that the (\mathrm{H}{3}^{+})emissions extend significantly above Jupiter's limb in the north polar region and to a lesser degree in the south polar region. This could be due to either a highly extended thermosphere or a broad energy spectrum of precipitating particles in the auroral regions. After we applied a new technique to the (\mathrm{H}{3}^{+})images to remove limb brightening, we found autoral ovals in both polar regions. The northern oval appears to be close to the (L=30) footprint in the magnetospheric (\mathrm{O}{6}) model, and it is significantly poleward compared with bright spot locations derived from previous analyses. One intrinsically bright area is found in the northern oval approximately at (150^{\circ}) longitude (System III) and (70^{\circ}) latitude, where the oval is also wider than elsewhere. The intensity of the bright area varies with a time scale as short as (\mathbf{5 0} \mathrm{min}). The southern oval seems to occur at latitudes higher by a few degrees than the (L=30) footprint, although (L=30) is within the uncertainty of latitude determination. One or two localized intensity maxima are found in the southern oval between (0^{\circ}) and (70^{\circ}) longitude. O 1994 Academic Press, Inc.