Patent ID: 7510664

Claim:
A method for shaping optical elements, comprising: positioning a distal end of a plasma torch in proximity to a surface so that at least one reactive species from the plasma torch affects the surface, the plasma torch including an outer gas inlet tube, an auxiliary gas inlet tube concentrically arranged within the outer gas inlet tube, an inner gas inlet tube concentrically arranged within the auxiliary gas inlet tube, and a load coil arranged at a distal end of the outer gas inlet tube so that the outer gas inlet tube is nested within the load coil; injecting a plasma gas into the outer gas inlet tube; applying a current to the load coil to inductively couple a radio frequency (RF) power to the plasma gas; creating an annular plasma; injecting an auxiliary gas into the auxiliary gas inlet tube to at least partially shield the inner gas inlet tube from the annular plasma; injecting a reactive precursor into the inner gas inlet tube; exciting the precursor with the radio frequency (RF) power via the annular plasma to create the at least one reactive species; and using the at least one reactive species for the damage-free shaping of the surface.