A drill, such as a spade drill, is provided. A plane on which the conductor crosses a plurality of sides in the planes forming a cell is divided by the conductor. A cylindrical adapter 6 inserted into the circular recess 10 is provided so as to operate the operating protrusion 5a. The designs make use of adiabatic modal evolution and do not require physical symmetry along the entire device length. Preferably, the at least two rendering processes are each capable of correctly rendering different sets of stroked curves.