2.B.2.Numerically controlled optical finishing machine tools equipped for selective material removal to produce non-spherical optical surfaces having all of the following characteristics:

a. Finishing the form to less (better) than 1.0 µm;
b. Finishing to a roughness less (better) than 100 nm rms;
c. Four or more axes which can be coordinated simultaneously for "contouring control"; and
d. Using any of the following processes:
1. 'Magnetorheological Finishing' ('MRF');
2. 'Electrorheological Finishing' ('ERF');
3. 'Energetic particle beam finishing';
4. 'Inflatable membrane tool finishing'; or
5. 'Fluid jet finishing'.
Technical Notes
For the purposes of 2.B.2.:
1. 'MRF' is a material removal process using an abrasive magnetic fluid whose viscosity is controlled by a magnetic field.
2. 'ERF' is a removal process using an abrasive fluid whose viscosity is controlled by an electric field.
3. 'Energetic particle beam finishing' uses Reactive Atom Plasmas (RAP) or ion-beams to selectively remove material.
4. 'Inflatable membrane tool finishing' is a process that uses a pressurized membrane that deforms to contact the workpiece over a small area.
5. 'Fluid jet finishing' makes use of a fluid stream for material removal.