The Tropospheric Emission Spectrometer (TES) is one of the instruments slated to fly on the EOS Aura satellite in 2003. TES is a Fourier transform spectrometer designed to measure the concentration of various tropospheric chemical species. The Focal Plane Opto-Mechanical Assemblies (FPOMAs) are situated at the end of the TES optical train and are comprised of cryogenic telescopes, reimaging optics, and focal planes. We present the cryogenic optical design of the FPOMA units and discuss optimization parameters and predicted performance. We present measured performance data and compare it with the predicted performance.