Claims to an apparatus must distinguish on the basis of structure, not function
Text from Ex parte George
As a first matter, we note that the claim is directed to an apparatus. “Claims drawn to an apparatus must distinguish from the prior art in terms of structure rather than function.” In re Danly, 263 F.2d 844, 848 (CCPA 1959).
Moreover, Appellants appear to have merely discovered a new benefit, i.e., modified radial variation in plasma density, for a shield having a range of radii relative to the axis of symmetry and variable apertures. This new plasma density benefit need not have been recognized in the prior art to have rendered the claim obvious. Boston Scientific v. Cordis, 554 F.3d 982,991 (Fed. Cir. 2009). We emphasize that the claim is directed to an apparatus and, therefore, must be distinguished from the prior art in terms of structure rather than function. There is no evidence that the function of producing a modified radial variation characteristic requires a structure different from that suggested by the prior art combination.