Patent ID: 7381311

Claim:
In a filtered cathodic-arc plasma source having: a consumable cathode with an end working surface emitting cathode-material plasma in response to vacuum arc engagement; a tubular anode adjacent and coaxial with said consumable cathode cathodic and anodic plasma focusing magnetic coils surrounding said consumable cathode and said tubular anode respectively; said consumable cathode, tubular anode and focusing magnetic coils comprising a first plasma generator; a plasma filter disposed in communication with said first plasma generator and including input and output rectilinear plasma ducts each surrounded by direct current magnetic coils; said plasma ducts and said plasma generator anode comprising a plasma-guiding channel having at least one exit opening and having a channel configuration exclusive of direct line-of-sight plasma communication between said plasma generator cathode and said exit opening; and electrical energy power supplies for said vacuum arc and said magnetic coils; the improvement comprising: said input and output rectilinear plasma ducts connect in a right angle junction wherein a wall opening in said input plasma duct enables plasma communication between said input and output rectilinear plasma ducts; said direct current magnetic coils surrounding said input and output rectilinear plasma ducts are supplemented by first and second magnetic field lines adjustment magnetic coils disposed around said input and output rectilinear plasma ducts at said right angle junction and energized by electrical energy power supplies; and said electrical energy power supplies for said direct current magnetic coils surrounding said input and output rectilinear plasma ducts and for said magnetic field lines adjustment magnetic coils include magnetic field adjustment means for configuring magnetic field lines within said output plasma duct as smooth, plasma conveying, low plasma loss continuations of magnetic field lines within said input plasma duct.