| 摘要 |
PURPOSE:To apply easily tracking control by using a refractive index distribution type lens and a polarization plane maintaining fiber so as to fit a laser light supply source and a detection optical system at a position separated from a main magnetic pole. CONSTITUTION:A thin film main magnetic pole 4 is supported to one end of a cantilever 10, a laser light is led from the other end of the cantilever 10 via the polarization plane maintaining fiber 9 and the laser light is irradiated to the tip of the main magnetic pole through the optical system including the refractive index distribution lenses 8, 6. Then the reflected or transmitted laser light is extracted at the outside of the cantilever via the original optical system and fiber and fed to a photodetector. thus, the part in contact with a medium is made light to facilitate the movement of the cantilever supporting the main magnetic pole and the tracking control is facilitated. |
