air gap near one external surface of a conventional core 110 in a tape wound or laminated inductor is shown inductor core 110 includes a first and second section 112 114 separated by an air gap 116 each core section is preferably formed of alternating layers of conductive ferromagnetic and relatively thin insulative material the conductive ferromagnetic layers 111 are shown it is to be understood that insulating layers separate each of the conductive ferromagnetic layers to minimize eddy currents within the core itself it is also to be understood that the conductive nature of the ferromagnetic material is an undesirable but currently unavoidable property of such materials without which eddy current losses in the core would not be a concern in use a magnetic field is produced across air gap 116 and a fringe field 150 develops near the ends of the gap the arced lines 151 indicate the direction of this field and their increased spacing indicates a weakening of the field away from the gap referring back to fig1 a this field forms eddy currents 117 118 in the broad surfaces 119 120 of the outer tape or lamination on each of the core sections 112 114 as noted above the eddy current in turn produces.