A direct current to alternating current inverter sub-system is for a HVDC distribution system. Microscope images of the same or very similar subjects provided by different microscopes are aligned. Preferably, the structure 12 is a coronary stent. A field concentrator 56 is provided to concentrate the induction field 54 in a desired region away from the linearly displaceable electrically conductive cutting member 14 and other electrically conductive component parts of the apparatus 10 to optimize the induction heating of the cut portion 18 of sealing material. At this time, a first portion of the photoresist pattern which is located between the source electrode and the drain electrode is thinner than a second portion which is located on the data wire, and the photoresist layer is totally removed on other parts.