To observe coronal magnetic fields with Gauss-level resolution and integration times significantly less than an hour, a meter-class coronagraph is required. Classical refracting designs are attractive for several reasons. It is easier to achieve and maintain low levels of scattered light with a r... Show moreTo observe coronal magnetic fields with Gauss-level resolution and integration times significantly less than an hour, a meter-class coronagraph is required. Classical refracting designs are attractive for several reasons. It is easier to achieve and maintain low levels of scattered light with a refracting primary, and they have very low levels of polarization cross-talk. A meter-class fused-silica lens, however, might weigh over 400 Kg. This work examines the deformation of such a lens under its own weight and with vacuum loading with several different configurations (f/number, lens diameter, lens thickness, etc.). The optical distortion and levels of stress-induced birefringence are determined. We find that a 1.5m lens of fused silica would meet all requirements for COSMO. Show less
