and an amount t of recession or spacing of an edge of the shield 15 against the external magnetic field from the plane of the air bearing surface 14 with respect to a surface of the media as shown an edge of the main pole 12 which faces the media 1 is arranged at the plane of the air bearing surface 14 and the edge of the shield 15 which faces the media 1 is spaced from the plane of the air bearing surface 14 it has been found that it is preferable that the gap interval l between the main pole 12 and the shield 15 against the external magnetic field falls in a range of 0 5 through 3 u03bcm and it is preferable that the amount t of recession or spacing of the shield 15 against the external magnetic field from the plane of the air bearing surface 14 with respect to the media falls in a range of 0 5 through 3 u03bcm further it is preferable that a size of the shield 15 against the external magnetic field is larger than that of the main pole 12 particularly with regard to a position of an edge thereof in a direction remote from the plane of the air bearing surface 14 with respect to the media it is preferable that the position of the edge of the shield 15 is higher than a position of an edge of the main pole 12 remote from the plane of the surface 14 with respect to the media by 1 through 10 u03bcm t because when the position is excessively high there is brought about an effect of collecting.