Correction of Short Spatial Wavelength Errors Using Ion Beam Figuring

Abstract

Considerable interest exists for correcting spatial wavelength surface figure errors on the order of 1 to 2 cm on large and small optical elements. These errors can result from conventional processes that cause print-through (i.e. optical quilting) on lightweighted optics, severe zonal or rolled edges on non-symmetric geometries, or short wavelength errors on small optics. Ion beam figuring, which is extremely efficient for correcting low-order aberrations, has also been utilized to correct these errors. Several examples of this capability will be presented.