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We report divergence, astigmatism, and beam propagation factor (M2) measurements of quantum cascade lasers (QCLs) with emission wavelengths of 8.77 mum. Emission profiles from the facet showed full-width at half-maximum divergence angles of 62deg and 32degplusmn2deg for the fast and slow axes, respectively. Diffraction-limited Ge aspheric microlenses were designed and fabricated to efficiently collect, collimate, and focus QCL emission. A confocal system comprised of these lenses was used to measure M2 yielding 1.8 and 1.2 for the fast and slow axes, respectively. Astigmatism at the exit facet was calculated to be about 3.4 mum, or less than half a wave. To the best of our knowledge, this is the first experimental measurement of astigmatism and M2 reported for midinfrared QCLs.