Abstract
Ion beam sputtering has emerged as a viable means of removing material from an optical surface. Ion beam sputtering was first used as an optical figuring technique in the mid 1960’s [1,2]. Since that time, a number of investigators have applied ion beam sputtering as a fabrication technique, with some degree of success. However, these early efforts were severely limited by the availability of suitable ion sources. The ion sources were typically low correct (fraction of a milliampere), high energy (20KeV to a fraction of an MeV) ion sources, with a very narrow beam, usually a millimeter or less in diameter. The low beam current produced low material removal rate, while the high beam energy was often found to induce mechanical, radiation, or chemical damage in the surface.